WO2019027477A1

WO2019027477A1 - Tactile crispness indicator

Info

Publication number: WO2019027477A1
Application number: PCT/US2017/045601
Authority: WO
Inventors: Angele Sjong
Original assignee: Xinova, LLC
Priority date: 2017-08-04
Filing date: 2017-08-04
Publication date: 2019-02-07

Abstract

Apparatuses and methods for a tactile crispness indicator are provided. An example apparatus includes an indicator attached to an interior surface of a container. The indicator may be configured to have a first state when an ambient moisture level within the container is below a threshold and a second state when the ambient moisture level within the container is above the threshold. In the second state, the indicator may be further configured to produce a perceptible tactile change externally through the interior surface of the container, indicative that the ambient moisture level has exceeded the threshold.

Description

TACTILE CRISPNESS INDICATOR

BACKGROUND

[001] One of the major causes of snack food rejection by consumers is the absorption of moisture. Moisture absorption by snack food alters textural characteristics, such as crispness, of the snack food. Typically, moisture softens the starch-protein matrix and greatly decreases the mechanical strength of the snack food. Thus, consumers often reject snack foods that have been softened by moisture.

[002] Efforts to reduce humidity usually involve placing a desiccant or other moisture scavenging material in the container, and typically sensors are not utilized to indicate a moisture level. Moreover, conventional moisture sensors rely on a visual change, change in conductivity/resistivity, or gravimetric change. However, these conventional techniques typically rely on visual identification, posing challenges for opaque containers.

SUMMARY

[003] Techniques are generally described that include apparatuses, systems, and methods.

An example apparatus includes an indicator attached to an interior surface of a container. The indicator may be configured to have a first state when an ambient moisture level within the container is below a threshold, and to have a second state when the ambient moisture level within the container is above the threshold, in the second state, the indicator may be further configured to produce a perceptible tactile change externally through the interior surface of the container, indicative that the ambient moisture level has exceeded the threshold.

[004] In some examples, the indicator may be configured to maintain a first shape in the first state, and a second shape, different than the first shape, in the second state. In other examples, the indicator may be configured to have a first stiffness in the first state, and a second stiffness that is more rigid than the first stiffness in the second state. In further examples, the indicator may further be configured to be substantially fiat in the first state, and to be curved in the second state. The indicator may further include a plurality of fibers configured to extend at a non-orthogonal angle to a longitudinal axis of the indicator, and aligned to extend in a common direction.

] In some examples, the indicator further comprises a plurality of hygroscopic dots configured to expand in the presence of moisture. The plurality of hygroscopic dots may be configured to have a height less than or equal to 20 μτη in the first state, and a height that is greater than or equal to 90 μτη in the second state. In a further example, the indicator may include a first layer and a second layer. In response to exposure to moisture within the container, the first and second layers may undergo a differential swelling response, wherein the differential swelling response produces a shape change in the indicator,

] Another example apparatus may include a container including an exterior surface and an interior surface, and an indicator adjacent to the interior surface of the container. The indicator may be configured to have a first state when the moisture level within the container is below a threshold, and to have a second state when the moisture level within the container is above the threshold.

] In some examples, a plurality of indicators, including the indicator, may be distributed over the interior surface of the container. In another example, the indicator may be positioned within a defined portion of the interior surface of the container. In an example, the indicator may be configured to maintain a first shape in a first state, and a second shape, different from the first shape, in the second state. In a further example, the indicator may be configured to have a first stiffness in the first state, and a second stiffness that is more rigid than the first stiffness in the second state. In another example, the indicator may be configured to be substantially fiat in the first state, and to be curved in the second state. The indicator may include a plurality of fibers configured to extend at a non- orthogonal angle to a longitudinal axis of the indicator, and aligned to extend in a common direction. In some examples, the indicator may further include a plurality of hygroscopic dots configured to expand in the presence of moisture. [008] In various examples, in the second state, the indicator may be configured to produce a perceptible tactile change externally through the interior suiface of the container, indicative that the moisture level has exceeded the threshold.

[009] An example method includes positioning an indicator adjacent to an interior suiface of a container, wherein the indicator is in fluid communication with an interior volume of the container, maintaining the indicator in a first state when the moisture level is below a threshold, changing the indicator to a second state when the moisture level is above the threshold, and transmitting, via the indicator in the second state, a perceptible tactile change externally to an exterior suiface of the container through the interior surface of the container.

[010] In some examples, the method may further include arranging the indicator to be located within a defined portion of the container. In some examples, the indicator may include a first layer, and a second layer. Thus, the method may further include positioning both the first and the second layers to be in fluid communication with the interior of the container, and undergoing, responsive to the moisture level being above the threshold, a differential swelling response, wherein the differential swelling response produces a shape change in the indicator. In another example, the method includes detecting, via the exterior surface of a container, an increase in humidity within the container based, at least in part, on the perceptible tactile change produced by the indicator in the second state.

[011] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

[012] The foregoing and other features of the present disclosure wiil become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. Understanding that these drawings depict only several examples in accordance with the disclosure and are, therefore, not to be considered limiting of its scope, the disclosure will be described with additional specifi city and detail through use of the accompanying drawings, in which:

[013] FIG. I is a perspective view of a flexible-rigid configuration of an indicator;

[014] FIG. 2 is a perspective view of a differential swelling configuration of an indicator;

[015] FIG. 3 is a perspective view of a braille-dot configuration of an indicator;

[016] FIG. 4 is a front elevation view of a container including one or more flexible-rigid indicators;

[017] FIG. 5 is a front elevation view of a container including one or more differential swelling indicators;

[018] FIG. 6 is a front elevation view of a container including one or more braille-dot indicators; and

[019] FIG. 7 is a sectional view of a container including one or more indicators,

[020] all arranged in accordance with at least some embodiments of the present

disclosure.

DETAILED DESCRIPTION

[021] In the following detailed description, reference is made to the accompanying

drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. The illustrative examples described in the detailed description, drawings, and claims are not meant to be limiting. Other examples may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented herein. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the Figures, can be arranged, substituted, combined, separated, and designed in a wide variety of different configurations, all of which are implicitly contemplated herein.

[022] This disclosure is drawn, inter alia, to methods, systems, products, devices, and/or apparatus generally related to a tactile crispness indicator. For example, a tactile crispness indicator may be utilized to monitor the condition (e.g., crispness) of a food product in a container holding the food product by monitoring for moisture. If moisture levels above a threshold are detected, the indicator may indicate the presence of moisture externally, through the container, via tactile feedback.

] Examples of tacti le crispness indicators may include an indicator attached to an interior surface of a container. The indicator may be configured to have a first state when an ambient moisture level within the container is below a threshold, and a second state when the ambient moisture level within the container is above the threshold. In the second state, the indicator may further be configured to produce a perceptible tactile change externally through the interior surface of the container, indicative that the ambient moisture level has exceeded the threshold.

] FIG. 1 is a perspective view of a flexible-rigid configuration of an indicator 100, in accordance with various embodiments. The indicator 100 in the flexible-rigid

configuration may include a body 105 and an optional adhesive layer 1 10. In various embodiments, each of the body 105 and the optional adhesive layer 110 may have a thin, sheet-like structure. In some embodiments, the indicator 100 may include multiple laminated sheets in addition to the body 105, or may be integrated into the walls of a container holding a food product. In other embodiments, the body 105 and adhesive layer 110 may have a non-flat shape, including, without limitation, a rod-like shape, coiled shape, or other suitable shape. The various components described in FIG. 1 are merely examples, and other variations, including eliminating components, combining components, and substituting components are all contemplated.

] In various embodiments, the body 105 may be attached to the interior of a container holding a food product. In some embodiments, optional adhesive layer 1 10 may be configured to attach the body 105 to an interior surface of the container. In other embodiments, the body 105 may be configured to attach directly, without the adhesive layer 1 10, to the interior surface of the container. In yet further embodiments, the body 105 may be integrated into the walls of the container. For example, the body 105 may be laminated between the two or more layers of a laminated snack bag. Thus, the body 105 may be coupled to an interior surface of a container, or alternatively, integrated into the walls of a container itself. In yet further embodiments, the indicator 100 may be detached from any surfaces, and free to move within a defined area of the container. For example, the indicator 100 may be free to move within a headspace of the container.

[026] In various embodiments, the body 105 may be disc-like in shape. In other

embodiments, the body 105 may be formed in any other suitable shape, including, without limitation, square, rectangular, polygonal, or irregular. In yet further embodiments, the body 105 may be substantially elongated in shape, such as a rod or strip. Thus, the body 105 should not be taken as limited in shape.

[027] In various embodiments, the body 105 may be configured to be flexible in a first state, and rigid in a second state. As used herein, flexibility and rigidity may refer to the stiffness - for example, the abi lity to resist deformation - of the body 105 of the indicator 100. W hile in the first state, the indicator 100 and/or body 105 may be undetectable via tactile sensing (e.g., touch), through the walls of the container. However, when the body 105 transitions to the second state, the rigid disc may become detectable, via tactile sensing, through the walls of the container. For example, in some embodiments, the indicator 100 and/or body 105 may be detected through the walls of the container by manipulation of the walls of the container, such as a laminated snack bag.

[028] In various embodiments, the body 105 may maintain a flexible state when an

ambient moisture level is below a threshold. The body 105 may then transition to a rigid state when the ambient moisture level exceeds the threshold. For example, when the ambient moisture level rises above 1%, body 105 may begin to cure, causing the body 105 to become rigid. In some embodiments, the body 105 may become rigid via polymeric curing in the presence of moisture.

[029] The threshold moisture level at which the body 105 begins to cure may be

controlled by selection of the materials used in the body 105. In various embodiments, the threshold moisture level at which the body 105 begins to cure may be set between 0.5-3%. In other embodiments, the body 105 may be formulated to begin curing at a desired threshold moisture level, as required for a particular application. Example threshold moisture levels may include, without limitation 1%, greater than 1%, greater than 0.5%, etc. In some embodiments, ambient moisture level may refer to a moisture level in a defined volume in proximity to the indicator 100. For example, the defined volume may be the container in which the indicator 100 is sealed or otherwise enclosed. In some embodiments, the moisture level may be measured by mass, relative to other gases within the defined volume, or relative to the mass of food product in the container. For example, in some embodiments, moisture content greater than 0.65g of water per lOOg of solid may lead to loss of cnspness for a food product. Thus, the indicator 100 may be configured to begin curing at an ambient moisture level of 0.65%. In other embodiments, the moisture level may be measured by volume. Accordingly, the body 105 of the indicator 100 may be configured to be exposed to ambient moisture inside of a container. In embodiments where the indicator 100 is laminated or otherwise integrated into the walls of a container, at least one of the layers of the wall of the container facing the interior volume of the container may be moisture permeable. Therefore, the indicator 100 may be in fluid communication with the interior volume of the container.

[030] According to various embodiments, the body 105 of the indicator 100 may be a flexible film of pre-poiymer containing moisture curable polymeric linkages. In various embodiments, the indicator may contain a stoichiometric amount of moisture-curable reactive groups. The stoichiometry may be such that at the threshold ambient moisture level, the thin film undergoes curing, transforming into a rigid film. When rigid, the indicator 100 may be readily sensed tactilely through the exterior of the container (e.g., snack bag). In various embodiments, the pre-polymer may be a generally recognized as safe (GRAS) designated material, as will be discussed in more detail below.

[031 j In various embodiments, suitable pre-polymers may include, without limitation, various curable polyurethanes that have been formulated by selecting liquid isocyanates that are biocompatible, for example isocyanates derived from lysine. Lysine methyl ester diisocyanate (LDI) and lysine triisocyanate (LTI) are two such examples. LDI or LTI may^¬ be reacted into highly-branched urethane pre-polymers. These pre-polymers may have a higher viscosity, high molecular weight, and have low monomer toxicity associated with other isocyanates. The higher viscosity may also allow the formation of a coating that has some integrity, in contrast with low-molecular weight isocyanate monomers. [032] In various embodiments, the LTI and LDI-derived isocyanate pre-polymers may exhibit various characteristics including, without limitation, having GRAS precursor isocyanates, cure into a GRAS polymer, and have breakdown products that are also GRAS designated. The curing reaction of the pre-polymers may form cross-linked polyurethane. The curing reaction may also react with the adjacent film layers. The lysine-derived urethane pre-polymers may be configured to cure in the presence of moisture, to form a highly-branched polyurethane. For example, a first reaction with water may form an amine, followed by reaction to a urea bond. The reaction between the isocyanate and amine to form urea bonds produces carbon dioxide (C0₂). NCO-terminated pre-polymers derived from lysine isocyanates used to synthesize polyurethane resins typically have a viscosity exceeding 10,000cSt, with the ability to increase molecular weight and viscosity, providing sufficient mechanical integrity for use in printed film roll stock. Generally, LTI/LDI isocyanates may be desirable in some examples because they may be ingestible and have been applied during surgery to cure in vivo. LTI/DLI isocyanates may cure to flexible adhesives. In examples described herein, there may be a rigidity increase in the material that can be detected tactilely, however, the end product may still be a flexible material.

[033] In further embodiments, a control disc may be provided in addition to the indicator

100. The control disc may be used as a control, remaining flexible at any moisture level, for comparison with the indicator 100. Thus, by comparing the indicator 100 with the control disc, the state of the indicator 100 may be ascertained. Suitable materials for the twin disk may include, without limitation, polyethylene (e.g., low-density polyethylene (LDPE)), polypropylene, polystyrene, polyurethane, silicone rubber, or other suitable polymeric material.

[034] As previously described, the indicator 100 may be attached to an interior surface of a container. Example containers may include, without limitation, bags, boxes, clamshell containers, and other containers having a wall or surface to which the indicator 100 may be operably attached. In some embodiments, the walls of the container may include thin, flexible, laminated film or sheet, such as those found in snack bags for chips, cookies, and other food products. The walls of the container may be flexible and/or thin enough such that the indicator 100 may be tactilely sensed (e.g., felt), by a user or consumer, through walls of the container from the exterior of the container when the indicator 100 undergoes a perceptible tactile change (e.g., the body 105 transitions from the flexible first state to the rigid second state). In such embodiments, the body 105 may be attached to an interior surface of the wall of the container via the adhesive layer 110, heat sealing, or otherwise affixed to the interior surface of the container. In some examples, the walls of the container may be thicker (e.g., a cardboard box, a cereal box) and indicator 100 may still be able to be tactilely sensed.

[035] In other embodiments, the indicator 100 may not need to be attached to the interior surface of a container, and may instead be located in the interior of the container. For example, the indicator may be coupled to a seam of a container, such as a sealed bag, or otherwise located within the container to be accessible, by touch, from the exterior of the bag. In yet further embodiments, the container may have relatively rigid wails where the indicator 100 may not be able to be felt externally through the walls of the container. In such embodiments, the indicator 100 may be integrated into the walls of the container such that the body 105 may be felt or accessed externally. For example, a defined portion or area of the container may be constructed from a different material through which the indicator 100 may be felt.

[036] In some embodiments, a plurality of indicators 100 may be attached to the interior surface of a container. For example, the plurality of indicators 100 may be attached to the interior surface, and distributed throughout the wails of the container. In other

embodiments, the plurality of indicators 100 may be located within a defined area of the container. In some embodiments, the plurality of indicators 100 may be attached to the interior of the container near a headspace area of the container, or near a seam where the container is sealed. The plurality of indicators 100 may be arranged such that the plurality of indicators 100 are not able to be tactilely sensed in a first (e.g., flexible) state. However, in a second (e.g., rigid) state, the plurality of indicators 100 may be sensed from the exterior of the container by manipulation of the walls of the container.

Q ] In some embodim ents, the defined area of the container may be located in at a corner, by a seam, or near the top of the container such that the walls of the container may be collapsed around the indicators 100. In some further embodiments, the defined area may be labeled, color coded, or otherwise indicated on the exterior of the container.

Accordingly, by touching the defined area of, a user may be able to quickly ascertain the crispness of a food product.

] Accordingly, in various embodiments, the indicator 100 may be used to monitor the ambient moisture levels surrounding a food product, and assess the crispness of the food product within a container containing the food product. An ambient moisture level within the container may be monitored, as previously described. When the ambient moisture level exceeds a threshold, indicating loss of crispness of a food product (e.g., fried or baked snack foods), the indicator 100 may undergo a perceptible tactile change allowing the indicator 100 to be detected from the exterior of the container. Thus, a consumer or user may identify that the food product no longer meets the crispness requirements of a manufacturer or distributor, by touching a portion of the container proximate to the indicator 100.

] FIG. 2 is a perspective view 200 of a differential swelling configuration of an indicator 205A, 205B (collectively 205), in accordance with various embodiments. The indicator 205 in the differential swelling configuration may include a first layer 21 OA, 210B (collectively 2 0), and a second layer 215 A, 215B (collectively 215). In various embodiments, each of the first layer 210 and second layer 215 may be a thin, sheet-like structure. In some embodiments, the indicator 205 may include multiple laminated sheets in addition to the first layer 210 and second layer 215, or may be integrated into the walls of a container holding a food product. In other embodiments, the first layer 210 and second layer 215 may be configured to have other, alternative shapes, such as a round or elliptical shape, cylindrical shape, rod-like shape, curved or spiral shape, rectangular shape, polygonal shape, or an irregular shape. The various components described in FIG. 2 are merely examples, and other variations, including eliminating components, combining components, and substituting components are all contemplated. [040] In some embodiments, the first layer 210 and the second layer 215 may be coupled together (e.g., laminated) to form a bilayer film. For example, in some embodiments, the first layer 210 may be bonded to the second layer 215 via an adhesive, heat sealing, or ultrasonic weld. In various embodiments, the indicator 205 may be attached to the interior of a container holding a food product. In some embodiments, an adhesive may be utilized to attach the indicator 205 to an interior surface of the container. In other embodiments, the indicator 205 may be configured to attach directly, via one of the first layer 210 or second layer 215, to the interior surface of the container. In yet further embodiments, the indicator 205 may be integrated into the walls of the container. For example, the indicator 205 may be laminated between the two or more layers of a laminated snack bag. Thus, the indicator 205 may be coupled to an interior surface of a container, or alternatively, integrated into the walls of a container itself. In yet further embodiments, the indicator 205 may be detached from any surface, and free to move within a defined area of the container. For example, the indicator 205 may be free to move within a headspace of the container.

[041] In various embodiments, the indicator 205 may be strip-like in shape. In other embodiments, the indicator 205 may be formed in any other suitable shape, including, without limitation, elliptical, circular, square, rectangular, polygonal, or irregular in shape. In yet further embodiments, the indicator 205 may be substantially elongated in shape, such as a rod or strip. Thus, the indicator 205 is not limited shape.

[042] In various embodiments, the indicator 205A may be configured to be straight (e.g., flat) in a first state. In a second state, the indicator 205B may undergo a shape change. While in the first state, the indicator 205 A may be undetectable via tactile sensing (e.g., touch), through the wails of the container. However, when the indicator 205 transitions to the second state, the indicator 205 B may undergo a shape change to become detectable, via tactile sensing, through the walls of the container.

[043] For example, in some embodiments, the first layer 210 may be configured to have a first swelling response to moisture and the second layer 215 may be configured to have a second swelling response to moisture. Accordingly, the first layer 210 and second layer 215 may be configured to have a high differential between the first swelling response and the second swelling response. Thus, because the indicator 205 undergoes differential swelling, the indicator 205B, in the second state, may change in shape from the first state. The first layer 21 OA, in a first state, may have a surface in contact with the second layer 215A, configured to maintain a straight shape in the first state. When exposed to moisture, the first layer 210 may swell more rapidly than the second layer 215. Thus, as the first layer 21 OB expands to become larger than the second layer 21.5B, the first layer 210B may introduce a change in the shape of the indicator 205B, to become increasingly more curved, spiraled, or to take the form of another non-straight shape. In some embodiments, the first layer 210 may include a higher concentration of bio-fillers than the second layer 215. Bio-fillers may include dehydrated particles, such as cellulosic fibers, configured to expand in response to absorbing moisture. In various embodiments, the bio-fillers may be GRAS designated. Bio-fillers with high cellulosic content may be highly hygroscopic in a desiccated state. Thus, upon exposure to moisture, the first layer 210 may undergo more swelling relative to the second layer 215.

[044] In an alternative embodiment, the indicator 205 may be a single layer film that is configured to have a gradient swelling response to moisture. For example, the single layer of the indicator 205 may be configured to have a swelling response that is highest near a first surface of the indicator 205. The swelling response may decrease according to distance away from the first surface. In some embodiments, the indicator 205 may include a gradient of bio-fillers. The indicator 205 may include a concentration of bio-fillers that is highest near the first surface, which decreases according to distance from the first surface. Thus, upon exposure to low levels of moisture, the indicator 205 may undergo differential swelling that causes a shape change in the indicator 205, In further embodiments, the indicator 205 may be configured to have a swelling response that is highest near a first end (e.g., one of a distal or proximal end) of the indicator 205 that decreases according to distance away from the first end.

[045] In various embodiments, the indicator 205 may include bio-filler arranged to cause swelling in a lengthwise direction. Examples of suitable bio-fillers may include, without limitation, cellulose nanofibers, or micro-fibri Hated cellulose. In some embodiments, the shape change introduced in the indicator 205, may be a change in curvature of the i ndi cator 205, caused by differential lengthwise expansion. Thus, the shape change of the indicator 205 as a radius of curvature (R) may be expressed as:

&L d

T ^~ R

where L is the length, and d is the thickness of the indicator 205. In some embodiments, for low humidity environments, such as those found in containers holding food products (e.g., snack bags), length change may be less than 0.1%. Thus, in order to achieve a shape change that may be tactilely sensed, in various embodiments, the indicator 205 may be configured to be highly hygroscopic on one side, thus maximizing the first swelling response, and the thickness (d) of the indicator 205 may be selected to create a greater shape change. For example, in some embodiments, the indicator 205 may further be configured to have a thickness (d) below 60 μτη (or 0.002 in.). Thus, the thickness of the indicator 205 may be on the order of the thickness of conventional vertical form fill seal (VFFS) packaging film (0.0025 in.). Therefore, the change in shape in the indicator 205 may be tactilely sensed through the bag.

[046] In some further embodiments, to increase the curvature (e.g., decrease the radius of curvature), the thickness of the indicator 205 may be decreased to be less than 30 μηι. The indicator 205 may therefore be configured, at a thickness of less than 30 μηι, to change in shape, from straight to a coil-shape, which may more easily be sensed tactilely. In some embodiments, where the indicator 205 utilizes cellulosic fibers, the indicator 205 may be configured such that the cellulosic fibers are aligned in the same direction, and are offset at an angle relative to the longitudinal axis of the indicator 205. For example, in one embodiment, the fibers may be aligned at a 45-degree angle to a longitudinal axis (e.g., lengthwise direction) of the indicator 205. It is to be understood that in other

embodiments, other angular offsets may be utilized between 0 and 90 degrees relative to the longitudinal axis.

[047] As previously described with respect to FIG. 1, in various embodiments, the

indicator 205A may maintain a first state when an ambient moisture level is below a threshold. The indicator 205B may then change in shape the second state when the ambient moisture level exceeds the threshold. For example, when the ambient moisture level rises above 1 %, indicator 205 may expand sufficiently to cause a tactilely perceptible shape change. The threshold moisture level at which the indicator 205 undergoes a tactilely perceptible shape change may be controlled by selection of the materials used in the first and/or second layers 210, 215, and by controlling the concentration of bio-filler materials in the first and/or second layers 210, 215, In various embodiments, the threshold moisture level may be set between 0.5-3%. Example threshold moisture levels may include, without limitation 1%, greater than 1%, greater than 0.5%, etc. In some embodiments, ambient moisture level may refer to a moisture level in a defined volume in proximity to the indicator 205. For example, the defined volume may be the container in which the indicator 205 is sealed or otherwise enclosed. In some embodiments, the moisture level may be measured by mass, relative to other gases within the defined volume, or relative to the mass of food product in the container. For example, in some embodiments, moisture content greater than 0.65g of water per lOOg of solid may lead to loss of crispness for a food product. Thus, the indicator 205 may be configured to undergo a tactilely perceptible shape change at an ambient moisture level of 0.65%. In other embodiments the moisture level may be measured by volume. Accordingly, the indicator 205 may be configured to be exposed to ambient moisture inside of a container. In some embodiments, the indicator 205 may be laminated or otherwise integrated into the walls of the container. Thus, in some embodiments, at least one of the layers of the wall of the container facing the interior volume of the container may be moisture permeable.

As previously described, the indicator 205 may be attached to an interior surface of a container. Example containers may include, without limitation, bags, boxes, clamshell containers, and other containers having a wall or surface to which the indicator 205 may be operably attached. In some embodiments, the walls of the container may include thin, flexible, laminated film or sheet, such as those found in snack bags for chips, cookies, and other food products. The walls of the container may be flexible and/or thin enough such that the indicator 205 may be tactilely sensed (e.g., felt), by a user or consumer, through walls of the container from the exterior of the container when the indicator 205 undergoes a perceptible tactile change (e.g., the indicator 205 undergoes a shape change). In such embodiments, one of the first or second layers 210, 215 may be attached to an interior surface of the wall of the container via an adhesive, heat sealing, or otherwise affixed to the interior surface of the container.

[049] In other embodiments, the indicator 205 may not need to be attached to the interior surface of a container, and may instead be located in the interior of the container. For example, the indicator may be coupled to a seam of a container, such as a sealed bag, or otherwise located within the container to be accessible, by touch, from the exterior of the bag. In yet further embodiments, the container may have relatively rigid walls where the indicator 205 may not be able to be felt externally through the walls of the container. In such embodiments, the indicator 205 may be integrated into the walls of the container such that one of the first or second layers 210, 215 may be felt or accessed externally. For example, a defined portion or area of the container may be constructed from a different material through which the indicator 205 may be felt.

[050] In some embodiments, a plurality of indicators 205 may be attached to the interior surface of a container. For example, the plurality of indicators 205 may be attached to the interior surface, and distributed throughout the walls of the container. In other

embodiments, the plurality of indicators 205 may be located within a defined area of the container. In some embodiments, the plurality of indicators 205 may be attached to the interior of the container near a headspace area of the container, or near a seam where the container is sealed. The plurality of indicators 205 may be arranged such that the plurality of indicators 205 is not able to be tactilely sensed in a first (e.g., straight shape) state. For example, in the first state, the plurality of indicators 205 may feel smooth from the exterior of the container. However, in a second (e.g., shape change) state, the plurality of indicators 205 may be sensed from the exterior of the container by manipulation of the walls of the container.

[051] In some embodiments, the defined area of the container may be located in at a corner, by a seam, or near the top of the container such that the walls of the container may be collapsed around the indicators 205. In some further embodiments, the defined area may be labeled, color coded, or otherwise indicated on the exterior of the container.

[052] FIG. 3 is a perspective view 300 of a braille-dot configuration of an indicator

305 A, 305B (collectively 305), in accordance with various embodiments. The indicator 305 is depicted in a first state as indicator 305A, and in a second state as indicator 305B, The indicator 305 includes a plurality of hygroscopic dots 315A-315N (collectively 315), and substrate 31 OA, 310B (collectively 310). In various embodiments, the substrate 310 may be a flat, sheet-like structure. In some embodiments, the indicator 305 may be configured to have other, alternative shapes, such as a round or elliptical shape, cylindrical shape, rod-like shape, curved or spiral shape, rectangular shape, polygonal shape, or an irregular shape. The various components described in FIG. 3 are merely examples, and other variations, including eliminating components, combining components, and substituting components are all contemplated.

[053] In various embodiments, the plurality of hygroscopic dots 315 may be coupled to a surface of the substrate 310. The plurality of hygroscopic dots 315 may be deposited, or otherwise formed on the surface of the substrate 310. In some embodiments, the plurality of hygroscopic dots 315 may instead be integrated with, embedded within, or form part of the substrate 310, as opposed to being deposited on the surface of the substrate 310. In some embodiments, the indicator 305 may be coupled, via an adhesive, heat sealing, or ultrasonic weld, to the interior of a container holding a food product. In other

embodiments, the indicator 305 may be configured to attach directly to the interior surface of the container. Thus, the plurality of hygroscopic dots 315 may be arranged on a surface of the substrate exposed to the interior of the container. In further embodiments, the indicator 305 may be integrated into the walls of the container. For example, the indicator 305 may be laminated between the two or more layers of a container, such as a laminated snack bag. Thus, the indicator 305 may be coupled to an interior surface of a container, or alternatively, integrated into the walls of a container itself. In yet further embodiments, the indicator 305 may be detached from any surface, and free to move within a defined area of the container. For example, the indicator 305 may be free to move within a headspace of the container. In another alternative embodiment, the substrate 310 may be part of the walls of the container. Thus, the plurality of hygroscopic dots 315 may be attached directly to an interior surface of the container.

[054] In various embodiments, the substrate 310 may be strip-like in shape. In other embodiments, the substrate 310 may be formed in any other suitable shape, including, without limitation, elliptical, circular, square, rectangular, polygonal, or irregular in shape. In yet further embodiments, the substrate 310 may be substantially elongated in shape, such as a rod or strip. In some embodiments, the substrate 310 may be a flexible film that is less than 10 μηι in thickness. Thus, it is to be understood that the substrate 310 is not limited in shape.

[055] In various embodiments, the plurality of hygroscopic dots 315 may be configured to be undetectable via tactile sensing (e.g., touch) in a first state. However, in a second state, the plurality of hygroscopic dots 315 may change to become detectable via tactile sensing, through the walls of the container. For example, in some embodiments, the plurality of hygroscopic dots 315 may be small enough in the first state to be undetectable. In the second state, the plurality of hygroscopic dots 315 may be configured to grow in size to become detectable via tactile sensing. In other embodiments, in the plurality of hygroscopic dots 3 1 5 may be soft and/or flexible in a first state, rendering the plurality of hygroscopic dots 315 undetectable via tactile sensing. However, in the second state, the plurality of hygroscopic dots may be configured to become hard and/or rigid, allowing the plurality of hygroscopic dots 315 to be detected via tactile sensing. In yet further embodiments, the plurality of hygroscopic dots 315 may be configured to be a combination of both small and soft in the first state, and in the second state become larger andharder, causing the plurality of hygroscopic dots 315 to become tactilely perceptible,

[056] Thus, in some embodiments, the plurality of hygroscopic dots 315 may be

configured to have a swelling response to ambient moisture. For example, in some embodiments, when an ambient moisture level, in this example a moisture permeation rate, exceeds 0.1 g/m² per day, the plurality of hygroscopic dots 315 may transition from the first state to the second state, as described above. Each of the plurality of hygroscopi c dots 315 may have a substantially semicircular transverse cross-sectional shape. In other embodiments, each of the plurality of hygroscopic dots 3 15 may have other shapes including, without limitation, a spherical, crystalline, polyhedron, or irregular shape. The transverse cross-sectional shape of each hygroscopic dot of the plurality of hygroscopic dots 31 5 may have a respective length and height. When exposed to ambient moisture, the plurality of hygroscopic dots 315 may be configured to absorb moisture, causing the plurality of hygroscopic dots 31 5 to expand in at least one of a lengthwise direction, in height, or both. For example, in various embodiments, each of the plurality of hygroscopic dots may have a height in the range of 0 μηι to 20 μιη in the first state, and a height in the range of 90 \xm to 150 μη in the second state. In other embodiments, the plurality of hygroscopic dots may have a height that is less than or equal to one of 20, 25, or 30 μιη in the first state, and a height that is greater than or equal to one of 80, 85, or 90 μη in the second state. Thus, in various embodiments, the plurality of hygroscopic dots 315 may have a swelling response to moisture that results in a 4x to 9x nearly linear growth response in the height direction when an ambient moisture level exceeds a threshold. That is, the plurality of hygroscopic dots may grow in size anywhere from 4 times to 9 times in height,

[057] The plurality of hygroscopic dots 315 may transition to the second state through various mechanisms. For example, in some embodiments, the plurality of hygroscopic dots 315 may transition to the second state through uniform swelling of each of the hygroscopic dots 315. In other embodiments, the plurality of hygroscopic dots 315 may form, in its second state, on the substrate 310 through differential swelling. In yet further embodiments, the substrate 310, plurality of hygroscopic dots 315, or a combination of the substrate 310 and plurality of hygroscopic dots 315 may be configured to buckle into a new shape when transitioning from the first state to the second state.

[058] In various embodiments, the indicator 305 may maintain a first state when ambient moisture level is below a threshold. The indicator 305 may then transition to the second state when the ambient moisture level exceeds the threshold. A moisture level may refer to, without limitation, one of a moisture permeation rate, relative humidity, moisture level by mass relative to other gases, or moisture level by mass relative to the mass of the food product. Thus, an ambient moisture level may refer to a moisture level in a defined volume in proximity to the indicator 305. For example, the defined volume may be the container in which the indicator 305 is enclosed. At a moisture permeation rate of 0.1 g/m² per day, over a 45 day shelf life, snack foods and other food products typically become stale. The relative humidity at which a fried food product becomes stale is estimated to be between 25 to 32%. Thus, the indicator 305 may be configured to transition to the second state at a threshold which coincides with one of a moisture permeation rate of 0.1 g/m² per day, a relative humidity between 25 and 32%, or, as previously described, a moisture content greater than 0.65g of water per lOOg of solid. The threshold moisture level at which the indicator 305 undergoes a tactilely perceptible shape change may be controlled by selection of the materials used. Thus, the indicator 305 may be configured to undergo a tactilely perceptible shape change when an ambient moisture level exceeds one of the above thresholds. Accordingly, the indicator 305 may be configured to be exposed to ambient moisture inside of a container. In some embodiments, the indicator 305 may be laminated or otherwise integrated into the walls of the container. Thus, in some embodiments, at least one of the layers of the wall of the container facing the interior volume of the container may be moisture permeable.

[059] In various embodiments, suitable materials for the plurality of hygroscopic dots

315 may include, without limitation, bio-fillers as previously described, or hydrogels. The material for the plurality of hygroscopic dots 315 may have a linear swelling response to humidity levels, and may be coupled to other anaiytes (e.g., VOCs, copper ions). In various embodiments, the plurality of hygroscopic dots 315 may be an edible or GRAS designated material. The indicator 305 may further include a food-grade adhesive incorporated in it, configured to couple the indicator 305 to the walls of a container.

[060] As previously described, the indicator 305 may be attached to an interior surface of a container. Example containers may include, without limitation, bags, boxes, clamshell containers, and other containers having a wall or surface to which the indicator 305 may be operabiy attached. In some embodiments, the walls of the container may include thin, flexible, laminated film or sheet, such as those found in snack bags for chips, cookies, and other food products. The walls of the container may be flexible and/or thin enough such that the indicator 305 may be tactilely sensed (e.g., felt), by a user or consumer, through walls of the container from the exterior of the container when the indicator 305 undergoes a perceptible tactile change (e.g., the indicator 305 transitions from the first state to the second state). In such embodiments, the indicator 305 may be attached to an interior surface of the wall of the container via an adhesive, heat sealing, or otherwise affixed to the interior surface of the container.

[061] In other embodiments, the indicator 305 may not need to be attached to the interior surface of a container, and may instead be located in the interior of the container. For example, the indicator may be coupled to a seam of a container, such as a sealed bag, or otherwise located within the container to be accessible, by touch, from the exterior of the bag. In yet further embodiments, the container may have relatively rigid wails where the indicator 305 may not be able to be felt externally through the walls of the container. In such embodiments, the indicator 305 may be integrated into the walls of the container such that the plurality of hygroscopic dots 315 may be felt or accessed externally. For example, a defined portion or area of the container may be constructed from a different material through which the plurality of hygroscopic dots 315 of the indicator 305 may be felt.

[062] In some embodiments, the plurality of hygroscopic dots 315 may be attached

directly to the interior surface of a container. For example, the plurality of hygroscopic dots 315 may be attached to the interior surface, and distributed throughout the walls of the container. In other embodiments, one or more indicators 305 including the plurality of hygroscopic dots 315 may be located within a defined area of the container. In some embodiments, one or more indicators 305 may be attached to the interior of the container near a headspace area of the container, or near a seam where the container is sealed.

[063] In some embodiments, the defined area of the container may be located in at a corner, by a seam, or near the top of the container such that the walls of the container may be collapsed around the indicator 305. In some further embodiments, the defined area may be labeled, color coded, or otherwise indicated on the exterior of the container. Accordingly, by touching the defined area of, a user may be able to quickly ascertain the crispness of a food product.

[064] With respect to FIGS. 1-3, generally speaking, humans are capable of tactilely sensing features as in the micron and sub-millimeter range, and can dynamically detect surface structures may orders of magnitude smaller, for example, in some cases as small as lOnm. The sense of touch is classified as active or passive. It is currently accepted that for static touch (e.g., in the absence of movement or applied vibrations), the minimum feature size that can be detected is around 0.2 mm. Typical container wails, such as those found in snack bags, have a thickness of around 63.5 μτη. Thus, to be tactilely sensed, a structural variation may be introduced to the container wall by the indicator 100, 205, 305.

According to various embodiments, structural features introduced by the indicator 100, 205, 305 can be as small as 90 μτη. Thus, in the second state, the indicator 100, 205, 305 may have a thickness in the range of 90 μτη to 150 μηι. In the first state, the indicator 100, 205, 305 may have a thickness in the range of 10 to 20 μτη. Thus, the indicator 100, 205, 305 may undergo a perceptible tactile change, transitioning from the first state to a second state.

[065] FIG. 4 is a front elevation view 400 of a container 405 including one or more

flexible-rigid indicators 425, in accordance with various embodiments. The container 405 may include an indicator 425 and control disc 430 located within defined area 420, and an interior volume including a headspace 415 and a food product located in the bottom area 410. The various components described in FIG. 4 are merely examples, and other variations, including eliminating components, combining components, and substituting components are all contemplated.

[066] The indicator 425 may be located within the interior volume of the container 405.

For example, in some embodiments, the indicator 425 may be located in the headspace 415 of the container 405. In further embodiments, the indicator 425 may be attached to the interior surface of the container 405, As depicted, the indicator 425 may be located within a defined area 420 of the container 405. The indicator 425 and/or defined area 420 may be located in the headspace 415 of the container 405, A control disc 430 may be provided proximate to the indicator 425. The control disc 430 may be used as a control, remaining flexible at any moisture level, for comparison with the indicator 425. Thus, by comparing the indicator 425 with the control disc 430, the state of the indicator 425 may be ascertained.

] Typically, the headspace 415 of the container 405 is filled with nitrogen gas with a negligible ambient moisture level. The food product is typically located at the bottom area 410 of the container 405, depending on the orientation of the container 405. As previously described, the indicator 425 may include a body and optionally an adhesive layer.

] When the ambient moisture level within the interior volume of the container 405 reaches or exceeds a threshold moisture level, the indicator 425 may be configured to transition from a flexible first state to a rigid second state, allowing the indicator 425 to be tactilely sensed. For example, the indicator 425 may maintain a flexible state when an ambient moisture level is below a threshold. While in the first state, the indicator 425 may be undetectable via tactile sensing (e.g., touch), through the walls of the container 405. The indicator 425 may then transition to a rigid state when the ambient moisture level exceeds the threshold. For example, when the ambient moisture level rises above 1%, the indicator 425 may begin to cure, causing the indicator 425 to become rigid. In some embodiments, the indicator 425 may become rigid via polymeric curing in the presence of moisture. When the indicator 425 transitions to the second state, the rigid disc may become detectable, via tactile sensing, through the walls of the container 405. For example, in some embodiments, the indicator 425 may be detected through the walls of the container 405 by manipulation of the walls of the container, such as a laminated snack bag. ] In some embodiments, the indicator 425 may be arranged to protrude through the walls of the container 405 such that the indicator 425 feels bumpy and/or rough to the touch. In further embodiments, the orientation of the indicator 425 may be adjusted to create a desired tactile effect. Thus, when the indicator 425 transitions to the second state, it may undergo a perceptible tactile change that allows it to be felt through exterior of the container 405. [070] FIG, 5 is a front elevation view 500 of a container 505 including one or more differential swelling indicators 525A-525N (collectively 525), in accordance with various embodiments. The container 505 may include an interior volume including a headspace 515 and a food product located in the bottom area 510. The various components described in FIG. 5 are merely examples, and other variations, including eliminating components, combining components, and substituting components are all contemplated.

[071] The plurality of indicators 525 may be located within the interior volume of the container 505, For example, in some embodiments, the plurality of indicators 525 may be located in the headspace 515 of the container 505. In further embodiments, the plurality of indicators 525 may be attached to the interior surface of the container 505, As depicted, the plurality of indicators 525 may be located within a defined area 520 of the container 505. The plurality of indicators 525 and/or defined area 520 may be located in the headspace 515 of the container 505. As previously described, with respect to FIG. 4, the headspace 515 of the container 505 may be filled with nitrogen gas with a negligible ambient moisture level. The food product is typically located at the bottom area 510 of the container 505, depending on the orientation of the container 505.

[072] The plurality of indicators 525 may include a first layer with a first swelling

response, and a second layer with a second swelling response. When the ambient moisture level within the interior volume of the container 505 reaches or exceeds a threshold moisture level, the plurality of indicators 525 may transition from a flat first state to a second state in which the plurality of indicators 525 undergoes a perceptible tactile change. For example, the plurality of indicators 525 may be configured to be straight (e.g., flat) in a first state. In a second state, plurality of indicators 525 may undergo a shape change.

While in the first state, the plurality of indicators 525 may be undetectable via tactile sensing (e.g., touch), through the walls of the container 505. However, when the plurality of indicators 525 transitions to the second state, the plurality of indicators 525 may undergo a shape change to become detectable, via tactile sensing, through the walls of the container 505. [073] In some embodiments, each respective first layer of the plurality of indicators 525 may be configured to have a first swelling response to moisture and each respective second layer of the plurality of indicators 525 may be configured to have a second swelling response to moisture. As previously described, each first layer and each second layer may be configured to have a high differential between the first swelling response and the second swelling response, causing each of the plurality of indicators 525 to change in shape, producing a perceptible tactile change.

[074] In an alternative embodiment, each of the plurality of indicators 525 may be a single layer film that is configured to have a gradient swelling response to moisture. For example, each of the plurality of indicators 525 may be configured to have a swelling response that is highest near a first surface of a respective indicator. The swelling response may decrease according to distance away from the first surface. For example, each of the plurality of indicators 525 may include a concentration of bio-fillers that is highest near the first surface, which decreases according to distance from the first surface. Thus, upon exposure to low levels of moisture, each indicator 525A-525N may undergo differential swelling that causes a shape change.

[075] In some embodiments, the plurality of indicators 525 may be arranged to feel

bumpy and/or rough to the touch. This may be accomplished by adjusting the number of indicators 525, as well as the spacing between indicators 525A-525N. In further embodiments, the orientation of each of the individual indicators 525A-525N may also adjusted to create a desired tactile effect. As previously described, each of the plurality of indicators 525 may have a thickness in a first state that is not detectible through the exterior of the container 505. When the indicator 525A-525 undergoes a shape change, a perceptible tactile change may occur which allows each of the plurality of indicators 525 to be felt through exterior of the container 505.

[076] FIG. 6 is a front elevation view 600 of a container 605 including one or more

braille-dot indicators 625 A-625N (collectively 625), in accordance with various embodiments. The container 605 may have an interior volume including a headspace 615 and a food product located in the bottom area 610. The various components described in FIG. 6 are merely examples, and other variations, including eliminating components, combining components, and substituting components are all contemplated.

[077] A plurality of indicators 625 may be located within the interior volume of the

container 605. For example, in some embodiments, the plurality of indicators 625 may be located in the headspace 615 of the container 605. In further embodiments, the plurality of indicators 625 may be attached to the interior surface of the container 605, As depicted, the plurality of indicators 625 may be located within a defined area 620 of the container 605. The plurality of indicators 625 and/or defined area 620 may be located in the headspace 615 of the container 605. Typically, the headspace 615 of the container 605 is filled with nitrogen gas with a negligible ambient moisture level. The food product is typically located at the bottom area 610 of the container 605, depending on the orientation of the container 605.

[078] In some embodiments, each of the plurality of indicators 625 may include a

respective substrate supporting a plurality of hygroscopic dots. In other embodiments, each of the plurality of indicators 625 may include one or more hygroscopic dots, as previously described. When the ambient moisture level within the interior volume of the container 605 reaches or exceeds a threshold moisture level, each indicator 625A-625N may transition from an undetectable first state to a second state, in which the each indicator 625A-625N undergoes a perceptible tactile change. For example, the plurality of indicators 625 may be configured to be undetectable via tactile sensing (e.g., touch) in a first state. However, in a second state, the plurality of indicators 625 may change to become detectable via tactile sensing, through the walls of the container 605. For example, in some embodiments, the plurality of indicators 625, or plurality of hygroscopic dots of the plurality of indicators 625, may be small enough in the first state to be undetectable by touch. In the second state, the hygroscopic dots of the plurality of indicators 625 may be configured to grow in size to become detectable via tactile sensing,

[079] In some embodiments, the plurality of indicators 625 may be arranged such that they feel bumpy and/or rough to the touch. This may be accomplished by adjusting the number of indicators 625, as well as the spacing between indicators 625A-625N. In further embodiments, the orientation of each of the individual indicators 625A-625N may also adjusted to create a desired tactile effect. As previously described, each indicator may have a thickness in a first state that is not detectible through the exterior of the container 605. When the plurality of indicators 625 it may then undergo a perceptible tactile change that allows it to be felt through exterior of the container 605. This will be described in further detail below with respect to FIG. 7.

] FIG. 7 is a sectional view 700 of a container 705 A, 705B (collectively 705) including one or more indicators 725A, 725B (collectively 725), in accordance with various embodiments. The container 705 may include an interior volume, including headspace 715 A, 715B (collectively 715), and a food product located in a bottom area 71 OA, 710B (collectively 7 0). The various components described in FIG. 7 are merely examples, and other variations, including eliminating components, combining components, and substituting components are all contemplated.

] A first view depicts the headspace 715 A of the container 705 A including the plurality of indicators 725 A in a first state. The plurality of indicators 725 A may be attached to an interior surface of the container 705. The plurality of indicators 725 A may be arranged in a defined area 720 A of the container 705. As illustrated, in the first state, when the defined area 720A is depressed by a user (e.g., consumer), the plurality of indicators 725 A may not be detectible. In some embodiments, the plurality of indicators 725 A in the defined area 720 A of the container 705 A may seem to be smooth from the exterior of the container 705 A. Thus, as previously described, in the laminated state, each of the plurality of indicators 725A may have a length Li (e.g., diameter), and a height H₁ (e.g., thickness). For example, in some embodiments, each hygroscopic dot of the plurality of indicators 725 A may be configured to have a height Hi in the range of 10 \xm to 20 μηι. In further embodiments, each hygroscopic dot of the plurality of indicators 725 A may be configured to have an Hj that is less than or equal to 20 μτη.

] A second view depicts the headspace 715B of the container 705B where the plurality of indicators 725B is in a second state. In the second state, each of the plurality of indicators 725B may have expanded, as previously described, in at least one of length or height. As depicted, in the second state, each of the plurality of indicators 725B has a length L₂ (e.g., diameter), and a height 1 i > (e.g., thickness). In the second state, the indicators 725B may be detectible by touch, by a user (e.g., consumer), by manipulating the defined area 720B of the container 705B. In some embodiments, the plurality of indicators 725B in the defined area 720B of the container 705B may seem rough to the touch, from the exterior of the container 705B. For example, in the second state, each hygroscopic dot of the plurality of indicators 725B may be configured to have a height H₂ in the range of 90 μιη to 150 μτη in the second state. In further embodiments, each hygroscopic dot of the plurality of indicators 725B may be configured to have an H₂ that is greater than or equal to 90 μηι.

] Accordingly, in some embodiments, the plurality of indicators 725B may create a deformation in the container 705B that may be tactilely sensed from the exterior surface 735 of the container 705B. This deformation of the walls of the container 705B can be seen in the defined area 720B, and may create a perceptible tactile change in the container 705B that may be felt from the exterior of the container 705B.

] Examples of indicators described herein, including indicators described with reference to FIG. 1 - FIG. 7, may combine a mechanical deformation with a visual indicator. In this manner, a mechanical deformation of the indicator may also provide a visually observable change. For example, indicators described herein may swell at low humidity and may also provide a buckling response. In this manner, a mechanical deformation of a sheet of the indicator (e.g., of body 105 of FIG. 1) may be substantially greater than swelling alone, and may be visually detected. Buckling may be accomplished in some examples by having a sheet of material used in the indicator be patterned with crosslinks. The crosslink pattern may give rise to a pattern of unequal swelling and drive a buckling response. The more highly crossiinked areas will not swell as much as weakly crosslinked areas. The crosslink patterning of the sheet may be accomplished using UV crosslinking and a patterned mask for the UV light exposure. Visually this may pucker or crinkle a small section of the bag coupled to the indicator, with the buckling response being programmable in accordance with the UV patterning mask. [085] In some examples, a passive RFID tag may be provided that responds to humidity. The passive RFID tag may include one or more indicator as described herein. For example, one or more antennae of an RFID tag may be moisture sensitive and/or a circuit utilized in the RFID tag may be complete or incomplete in the presence of humidity.

[086] Generally, a human finger may be quite sensitive to dynamically detect surface structures that are on the 10s to 100s nanometer amplitude and wrinkle wavelength.

Accordingly, tactile sensors described herein may be reliably detected in many examples without any use of an electrical power source to maintain the indicator.

[087] The present disclosure is not to be limited in terms of the particular examples

described in this application, which are intended as illustrations of various aspects. Many modifications and examples can be made without departing from its spirit and scope, as will be apparent to those skilled in the art. Functionally equivalent methods and apparatuses within the scope of the disclosure, in addition to those enumerated herein, will be apparent to those skilled in the art from the foregoing descriptions. Such modifications and examples are intended to fall within the scope of the appended claims. The present disclosure is to be limited only by the terms of the appended claims, along with the full scope of equivalents to which such claims are entitled. It is to be understood that this disclosure is not limited to particular methods, reagents, compounds compositions or biological systems, which can, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular examples only, and is not intended to be limiting,

[088] With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.

[089] It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as "open" terms (e.g., the term "including" should be interpreted as "including but not limited to," the term "having" should be interpreted as "having at least," the term "includes" should be interpreted as "includes but is not limited to," etc.).

] It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation, no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be constraed to imply that the introduction of a claim recitation by the indefinite articles "a" or "an" limits any particular claim containing such introduced claim recitation to examples containing only one such recitation, even when the same claim includes the introductory phrases "one or more" or "at least one" and indefinite articles such as "a" or "an" (e.g., "a" and/or "an" should be interpreted to mean "at least one" or "one or more"); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should be interpreted to mean at least the recited number (e.g., the bare recitation of "two recitations," without other modifiers, means at least two recitations, or two or more recitations).

] Furthermore, in those instances where a convention analogous to "at least one of A, B, and C, etc." is used, in general, such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, and C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase "A or B" will be understood to include the possibilities of "A" or "B" or "A and B." [092] In addition, where features or aspects of the disclosure are described in terms of Markush groups, those skilled in the art will recognize that the disclosure is also thereby described in term s of any individual member or subgroup of members of the Markush group.

[093] As will be understood by one skilled in the art, for any and ail purposes, such as in terms of providing a written description, all ranges disclosed herein also encompass any and all possible subranges and combinations of subranges thereof. Any listed range can be easily recognized as sufficiently describing and enabling the same range being broken down into at least equal halves, thirds, quarters, fifths, tenths, etc. As a non-limiting example, each range discussed herein can be readily broken down into a lower third, middle third and upper third, etc. As will also be understood by one skilled in the art ail language such as "up to," "at least," "greater than," "less than," and the like include the number recited and refer to ranges which can be subsequently broken down into subranges as discussed above. Finally, as will be understood by one skilled in the art, a range includes each individual member. Thus, for example, a group having 1 -3 items refers to groups having 1, 2, or 3 items. Similarly, a group having 1-5 items refers to groups having 1, 2, 3, 4, or 5 items, and so forth.

[094] While the foregoing detailed description has set forth various examples of the devices and/or processes via the use of block diagrams, flowcharts, and/or examples, such block diagrams, flowcharts, and/or examples contain one or more functions and/or operations, it will be understood by those within the art that each function and/or operation within such block diagrams, flowcharts, or examples can be implemented, individually and/or collectively, by a wide range of components, or any combination thereof.

[095] Those skilled in the art will recognize that it is common within the art to describe devices and/or processes in the fashion set forth herein, and thereafter use engineering practices to integrate such described devices and/or processes. That is, at least a portion of the devices and/or processes described herein can be integrated into other types of packaging and containers for products including those other than food products, via a reasonable amount of experimentation. [096] The herein described subject matter sometimes illustrates different components contained within, or connected with, different other components. It is to be understood that such depicted architectures are merely examples and that in fact many other architectures can be implemented which achieve the same functionality. In a conceptual sense, any arrangement of components to achieve the same functionality is effectively "associated" such that the desired functionality is achieved. Hence, any two components herein combined to achieve a particular functionality can be seen as "associated with" each other such that the desired functionality is achieved, irrespective of architectures or intermedial components. Likewise, any two components so associated can also be viewed as being "operably connected", or "operably coupled", to each other to achieve the desired functionality, and any two components capable of being so associated can also be viewed as being "operably couplable", to each other to achieve the desired functionality. Specific examples of operably couplable include but are not limited to physically mateable and/or physically interacting components and/or wirelessly interactable and/or wirelessiy interacting components and/or logically interacting and/or logically interactable components.

[097] While various aspects and examples have been disclosed herein, other aspects and examples will be apparent to those skilled in the art. The various aspects and examples disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.

Claims

CLAIMS What is claimed is:

1 . An apparatus comprising:

an indicator attached to an interior surface of a container;

wherein the indicator is configured to have a first state when an ambient moisture level within the container is below a threshold,

wherein the indicator is configured to have a second state when the ambient moisture level within the container is above the threshold,

wherein in the second state, the indicator is further configured to produce a perceptible tactile change externally through the interior surface of the container, indicative that the ambient moisture level has exceeded the threshold,

2. The apparatus of claim 1, wherein the indicator is further configured to maintain a first shape in the first state, and a second shape, different that the first shape, in the second state.

3. The apparatus of cl aim 1 , wherein the indicator is further configured to have a first stiffness in the first state, and a second stiffness that is more rigid than the first stiffness in the second state.

4. The apparatus of claim 1, wherein the indicator is further configured to be substantially flat in the first state, and to be curved in the second state.

5. The apparatus of claim 4, wherein the indicator includes a plurality of fibers configured to extend at a non-orthogonal angle to a longitudinal axis of the indicator, and aligned to extend in a common direction.

6. The apparatus of claim 1, wherein the indicator further comprises a plurality of hygroscopic dots configured to expand in response to moisture.

7. The apparatus of claim 6, wherein each of the plurality of hygroscopic dots is configured to have a height less than or equal to 20 μηι in the first state, and height that is greater than or equal to 90 μτη in the second state.

8. The apparatus of claim 1, wherein the indicator further comprises:

a first layer, and

a second layer;

wherein, in response to exposure to moisture within the container, the first and second layers undergo a differential swelling response, wherein the differential swelling response produces a shape change in the indicator,

9. An apparatus comprising:

a container including an exterior surface and an interior surface;

an indicator adjacent to the interior surface of the container,

wherein the indicator is configured to have a first state when a moisture level within the container is below a threshold, and

wherein the indicator is configured to have a second state when the moisture level within the container is above the threshold.

10. The apparatus of claim 9, wherein a plurality of indicators, including the indicator, are distributed over the interior surface of the container.

11. The apparatus of claim 9, wherein the indicator is positioned within a defined portion of the interior surface of the container.

12. The apparatus of claim 9, the indicator is configured to maintain the first shape in a first state, and a second shape, different from the first shape, in the second state.

13. The apparatus of claim 9, wherein the indicator is configured to have a first stiffness in the first state, and a second stiffness that is more rigid than the first stiffness in the second state.

14. The apparatus of claim 9, wherein the indicator is configured to be substantially flat in the first state, and to be curved in the second state.

15. The apparatus of claim 14, wherein the indicator includes a plurality of fibers configured to extend at a non-orthogonal angle to a longitudinal axis of the indicator, and aligned to extend in a common direction.

16. The apparatus of claim 9, wherein the indicator further comprises a plurality of hygroscopic dots configured to expand in response to moisture,

17. The apparatus of claim 9, wherein in the second state, the indicator is further configured to produce a perceptible tactile change externally through the interior surface of the container, indicative that the moisture level has exceeded the threshold.

18. A method compri sing :

positioning an indicator adjacent to an interior surface of a container, wherein the indicator is in fluid communication with an interior volume of the container;

maintaining the indicator in a first state when a moisture level is below a threshold; changing the indicator to a second state when the moisture level is above the threshold; and

transmitting, via the indicator in the second state, a perceptible tactile change externally to an exterior surface of the container through the interior surface of the container.

19. The method of claim 18, further comprising:

arranging the indicator to be located within a defined portion of the container.

20. The method of claim 18, wherein the indicator comprises a first layer, and a second layer, the method further comprising:

positioning both the first and second layers to be in fluid communication with an interior of the container; and

undergoing, responsive to the moisture level being above the threshold, a differential swelling response, wherein the differential swelling response produces a shape change in the indicator.

21. The method of claim 18, further comprising:

detecting, via the exterior surface of the container, an increase in humidity within the container based, at least in part, on the perceptible tactile change produced by the indicator in the second state.