FI127941B

FI127941B - Method of modifying feather raw material

Info

Publication number: FI127941B
Application number: FI20175869A
Authority: FI
Inventors: Anne Kallioinen; Jouko Savolainen
Original assignee: Hkscan Oyj; Uniq Bioresearch Oy
Priority date: 2017-10-02
Filing date: 2017-10-02
Publication date: 2019-05-31
Also published as: WO2019068960A1; FI20175869A1

Description

Method of modifying feather raw material

FIELD OF THE INVENTION

The present invention relates to the fields of meat industry and the production of proteincontaining ingredients. Particularly, the present invention is directed to the use of feathers, a byproduct of chicken meat production, for producing a protein-rich additive suitable for animal feeds, food industry, cosmetics products, packaging materials and also for coating or building materials such as cement and paints.

BACKGROUND OF THE INVENTION

Feathers contain keratin protein as a main component. Keratin is rich in disulfide bonds (i.e. disulfide bridges) that stabilize the structure and make it durable and rather difficult to digest and degrade. Keratin is also known to be highly insoluble in water. Only part of keratin can be enzymatically hydrolyzed by conventional proteases and it is also the reason why it is digested by animals rather poorly. Methods to increase digestibility and hydrolysis of keratin have thus been developed including chemical treatments as well as enzymatic treatments (see Pedersen et al., 2012; Staron et al., 2014; and Khosa and Ullah, 2013).

In EP 1731528, a mixture of water and keratin is hydrolyzed by alkali at 80-120 °C for 1 to hours and then neutralized to obtain a solubilized keratin. EP 2832236 describes a process, where keratinous material is hydrolyzed at elevated temperatures at pressures from about 2 bar to about 10 bar. The resulting hydrolyzed keratinous material is dried at temperatures below 90 °C to maintain the pepsin digestibility above 85%. In US 2012/0219667, a method producing soluble keratinous protein by treating keratin in oxidizing solution in low pH and heat is described. The oxidizing solution can be e.g. performic acid, peracetic acid or peroxide. The oxidizing step is followed by raising the pH to the pK_a of the proteins or to the point proteins are present in the salt form. The resulting protein solution can be used as nutritional supplement.

Further, EP 0499260 discloses sulphite treatments of feather material at 60-100°C and pH 6-9 for 10 minutes to 4 hours. The treated sulfonated feather mass was subsequently hydrolyzed by proteolytic enzymes into keratin hydrolysate and then concentrated. Ash content of the dry matter as high as 8.5% was reported. A use of the keratin hydrolysate as animal feed was suggested. In WO 03011894, a process consisting of oxidative sulphitolysis as a first stage and extraction by controlled washing by water as a second stage is described. The resulting keratin derivatives are high molecular weight soluble proteins that can be used in biopolymer applications. US 2015/0152153 discloses a

20175869 prh 02 -10- 2017 combined treatment by a reducing agent and a proteolytic enzyme, where the treatment with the reducing agent can be after, during or prior to the protease treatment. The hydrolyzed keratin produced by the method was suggested for use in animal feed.

Large quantities of feather are produced by poultry industry as a side stream. Usually, feathers are used in animal feed after high temperature treatments when the digestibility might be higher but part of amino acids are degraded decreasing the feed value. It is protein rich material that has a high potential commercial value and therefore cost efficient technologies suitable for industrial production that increase the digestibility in relatively mild temperature conditions and without harming amino acid composition are needed. One problem with the treatments with chemicals is often the resulting high salt concentrations that are not acceptable in food or feed products, and require excessive and often rather expensive downstream processing such as ultrafiltration to remove salts. The present invention is thus directed to the production of a feather-based ingredient with high protein content and low salt concentration.

SUMMARY OF THE INVENTION

The aim of the present invention is to modify durable and rigid feather keratin by improved reductive sulphitolysis reaction and pH adjustment steps to increase hydrolysability of feather keratin and in this way produce a protein-rich multipurpose additive.

The present invention is directed to a method of modifying feather raw material comprising the steps of:

(a) treating feather raw material in a first aqueous solution containing sulphite ions, wherein the treatment is carried out at pH 6-8, reaching temperature of about 90 °C, the treatment lasting at least 30 minutes;

(b) separating the sulfonated feather material obtained from step (a);

(c) treating the sulfonated feather material in a second aqueous solution, wherein the treatment is carried out at pH 1.5-3.0 and at temperature of 10 - 30 °C, the treatment lasting at least 5 minutes; and (d) adjusting the pH of the second aqueous solution or the feather material obtained from the second aqueous solution to at least pH 4.5 - 5.5.

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Another aim of the present invention is to provide a protein-rich modified feather product produced by the method as described above.

Another aim of the present invention is to provide a nutritional additive for animal feeds produced by the method as described above and also an animal feed comprising said nutritional additive.

Another aim of the present invention is to provide a protein-rich nutritional supplement for food industry produced by the method as described above and a food-product comprising said supplement.

Further aims of the present invention are the provision of a cosmetic ingredient, component for making improved packaging materials, or an additive for coating or building materials comprising the modified feather material manufactured by the method as described above.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1. Examples of process steps for feather modification.

Figure 2. (A) Untreated feather material and (B) modified dried feathers. Treatment was carried out as defined in the Experimental Section below in Lödige reactor at 90 °C, pH 7 for 40 min with sodium metabisulphite 0.225 g / g dry matter.

DETAILED DESCRIPTION OF THE INVENTION

In the present invention, significant increase in enzymatic hydrolysability of feather material can be obtained by the feather modification treatments disclosed herein compared to untreated feather and also to previous modification methods of the prior art. The protein content of the final modified feather powder product can be as high as 97% while ash content is only 0.4% of dry matter (w/w). The final product thus showed efficient washing of salts. Total bacteria content was below 40 CFU/g of dry matter and thus microbiological quality was good. In addition, free SH-groups of the final product are found to be antioxidative and thus have other health promoting effects.

Accordingly, the present invention provides a method of modifying feather raw material comprising the steps of (a) treating feather raw material in a first aqueous solution containing sulphite ions (to perform a sulfitolysis), wherein the treatment is carried out at pH 6 - 8, reaching temperature of about 90 °C, the treatment lasting at least 30 minutes;

(b) separating the sulfonated feather material obtained from step (a);

20175869 prh 02 -10- 2017 (c) treating the sulfonated feather material in a second aqueous solution, wherein the treatment is carried out at pH 1.5-3.0 and at temperature of 10 - 30 °C, the treatment lasting at least 5 minutes; and (d) adjusting the pH of the second aqueous solution or the feather material obtained from the 5 second aqueous solution to at least pH 4.5 - 5.5.

In the first step of the modification, i.e. step (a), the feather raw material is subjected to sulfitolysis. In this step, cleavage of disulfide bonds in feather keratin structures and modification of conformation are accomplished by sulfitolysis where a sulphite ion reacts specifically with one sulfur in the disulfide bond forming an S-sulfonate derivative. The other sulfur is reduced to a sulfhydryl group. The reagent that forms sulfite ions, preferably a sulphite salt, can be, e.g., soluble and food-grade sodium sulphite Na2SO₃, sodium hydrogensulphite NaHSCf or sodium metabisulphite Na2S20s. The dry matter content of the feather raw material in the solution is preferably in the range of 5 to 15% (w/w). In an embodiment, the feather raw material is chopped or grinded to a smaller particle size before the treatment. The first aqueous solution is preferably water and the feather raw material, e.g. chicken or turkey feathers, is mixed to the solution in a reaction vessel. Said feather raw material can be initially chopped or ground to smaller particle size. In a preferred embodiment, the sulphite salt is added to the mixture so that the sulphite content corresponds to the amount of sulphite provided by 0.15 - 0.25 g metabisulphite / g of feather raw material (dry matter). In a preferred embodiment, the sulphite content varies from 5 to 25% (w/w) dry matter in relation to the amount of feather raw material present in the first modification step, e.g. a preferred concentration of sulphite in the mixture, i.e. the first aqueous solution, is at least 0.1 M, more preferably between 0.1- 0.2 M. If required, pH is adjusted to the range of pH 6 - 8, preferably pH 6.5 - 7.5 or more preferably to about pH 7, for instance by using NaOH solution. After pH adjustment, the treatment is started by heating the reactor. Treatment time is at least 30 min, preferably at least 35 or at least 40 min. During the treatment, temperature is raised to about 90°C and then preferably controlled at 87-90°C, e.g. by using steam. The suspension in the reactor is preferably continuously mixed during the treatment.

In the first separation step, i.e. step (b), advantageously performed by filtration and preferably comprising a further washing step or washing steps, the sulfonated feather material is separated from the reaction solution to remove unreacted sulphite ions. Preferably, the removed sulphite in the form of sulphite rich washing water is recycled and used again in the first step of the present method. The separation/washing step also increases

20175869 prh 02 -10- 2017 the process safety as during the following step the pH is adjusted to pH 1.5 - 3.0, preferably to pH 2.0-3.0, and toxic gas, sulphur dioxide is formed. In a preferred embodiment, several batches of feather are collected in step (b) and treated subsequently in step (c).

In the second treatment step, i.e. step (c), the sulfonated feather material is mixed with a second aqueous solution, preferably water, wherein the pH is adjusted to the range of pH 1.5 - 3.0, e.g. by adding hydrochloric acid. The treatment lasts at least 5 minutes and is performed so that the suspension’s temperature is in the range of 10 - 30 °C, preferably 15 30 °C. At acidic conditions, sulphur dioxide is released from the sulphonated feather material as well as from the remaining unreacted sulphite reagent. The second treatment step thus results feather material with free sulfhydryl groups. Reactor suspension is also preferably continuously mixed during the second treatment.

In the following step, i.e. step (d), the pH is adjusted, preferably by using NaOH solution, to at least pH 4.5 - 5.5, preferably to pH >5, more preferably about pH 5. While increasing the pH, the remaining sulphur dioxide in the feather material is dissolved as sodium sulphite in the second aqueous solution.

For efficient washing of salts from the treated feathers, the material is preferably separated or filtrated from the second aqueous solution after the pH adjustment and subsequently mixed or immersed with water for washing the salts. In a preferred embodiment, the separation and washing steps are repeated at least once.

To obtain a powdered final product, milling of the feather material obtained from the previous steps can be carried out either by wet or dry milling, e.g. by a conical mill. Wet milling requires that modified feather can be pumped from the reaction vessel. Drying of the feather material thus obtained can be performed by the methods well-known in the art, such as vacuum dryingjet drying or freeze drying. Milling as dry is also possible in a process scale.

The present method may also comprise a further step of enzymatic hydrolysis. This stage is preferably performed after the milling step. For the hydrolysis reaction in an aqueous solution or buffer, the pH is controlled to be in the range of 6 to 10. The temperature is set from 30 to 80 °C, being dependent on the enzyme used. Appropriate enzymes are the neutral and alkaline proteases from different manufacturers, such as Alcalase 2.4L FG (Novozymes, Denmark). The amount of the enzyme is dispensed mainly by the amount of activity required. The amount of activity is determined mainly according to manufacturer’s instructions and the amount of substrate and the desired hydrolysis time.

20175869 prh 02 -10- 2017

The present invention is also directed to a protein-rich modified feather product produced by the method as defined above and to an animal feed comprising said product. Preferably, said product comprises powdered feather material having protein content more than 90% and ash content less than 1.5% (w/w), preferably less than 1.0% (w/w). More preferably, said product comprises modified feathers as the only protein source. As shown below in the Experimental Section, said powdered feather material also has higher enzymatic hydrolysability compared to untreated feather material.

The present invention is further directed to a nutritional additive comprising said protein-rich modified feather product. Said nutritional additive can be used as a supplement or ingredient 10 of an animal feed suitable for improving animal health. The feed for poultry or pigs, for instance, may include wheat, corn or soybean and the feed for a ruminant is typically hay or live grass. In order to increase the protein-content of the feed, the nutritional additive of the present invention is added to the feed in granular, powdered, pellet, tablet, or other form, preferably as powder. In a preferred embodiment, the nutritional additive of the present 15 invention is used as an ingredient of a ready-made animal feed product or feed additive product.

In principle, the resulting dried and milled protein-rich modified feather product is also suitable as food supplement for dissolving into liquid such as juice, milk, beverage or a nutritional drink, for sprinkling on food or mixing with other food ingredients. The disclosed 20 protein-rich modified feather product is suitable for protein supplementation for any purpose including, but not limited to, dietary supplements. The protein-rich modified feather product can also be provided as tablets, powders or incorporated into bars. The present invention is thus also directed to food products comprising the nutritional additive as defined above.

Further, the invention relates to a cosmetic additive comprising the protein-rich modified 25 feather product manufactured by the above-described method. The protein-rich modified feather product is expected to be blended in cosmetic products, such as hair cosmetics (for example, shampoos and hair conditioners), and skin-care products such as creams, lotions and ointments.

The cosmetic additive of the invention consisting of the protein-rich modified feather product can be blended together with various cosmetic ingredients, including various surface active agents such as anionic/cationic/nonionic surface active agents, synthetic polymers such as polyethylene glycol and propylene glycol, humidity retaining agents such as glycerin and butylene glycol, oil solutions such as animal and vegetable oil, ester oil, higher alcohols

20175869 prh 02 -10- 2017 and lower alcohols, silicone oil, animal and vegetable originated protein such as collagen, as well as preservatives and perfumes.

Feather-based ingredient can be incorporated in environmentally friendly packaging materials for improving their physicochemical properties. These include for example improved mechanical and barrier properties, water resistance, and biodegradability (see Gomez-Estaca et al, 2016).

In another embodiment, the protein-rich modified feather product obtained by the present method is an additive for coating or building materials such as cement or paint. The modified feather product may provide increased density, viscosity, shortened drying time for 10 cement and reduced volatile organic (VOC) content, better film-forming properties, better water resistance, and low toxicity for paints.

The publications and other materials used herein to illuminate the background of the invention, and in particular, to provide additional details with respect to its practice, are incorporated herein by reference. The present invention is further described in the following 15 Experimental Section, which is not intended to limit the scope of the invention.

EXPERIMENTAL SECTION

Materials and methods

Raw materials

Feather raw material was obtained from poultry production plant. The dry matter content of feather was about 50%. Two batches of raw material were obtained from HKScan. As a sulphite reagent, sodium metabisulphite was used.

Laboratory scale treatments of feathers

Laboratory scale experiments were carried out in a 10 1 steel vessel equipped with a mixer.

500 g of feathers (250 g DM) were suspended totally in 5 1 of water and heated to reaction temperature. Three different temperatures, 70°C, 80 °C and 90°C, were tested as well as two different pHs, pH 6.5 and pH 7.0. Sodium metabisulphite dosages of 0.14-0.2 g/g dry matter (DM) were applied.

Reaction time was 40 min. After reaction, pH was decreased to pH 2.0 and then pH was raised to pH 5.0. After pH adjustments, feather was washed. Feather was separated from the

20175869 prh 02 -10- 2017 suspension by filtering through a sieve. A clear but yellowish filtrate was obtained. Sample of the filtrate was taken to analyse DM and ash contents. Feathers were washed, filtrated again and dried in a heating chamber for overnight.

Small pilot scale treatments of feathers

Small pilot scale experiments were carried out in a 40 1 steel tank. 4 kg of feathers (2 kg DM) was added to 38 1 of water and was heated to 90 °C. Sodium metabisulphite (0.2250.250 g/g DM) was dissolved in of water and added to feather suspension and pH was adjusted to pH 7.0. Reaction time was 40 min. After reaction time, feather slurry was cooled and then filtrated through a sieve to separate feather from filtrate. Feathers were re10 suspended in water and pH was adjusted to pH 2.0. Sulphur dioxide was released in this reaction. Feathers were filtrated again, re-suspended in water, mixed thoroughly, filtrated again and then dried. A sample of the last filtrate was taken for DM and ash content assays.

Large pilot scale production of activated feathers

In the large pilot scale treatment of activated feathers, a 600 1 Lödige vertical reactor was used. Reactor was loaded with 55.2 kg feather (dry matter content 46.5%) and 480 1 water. 5.67 kg of sodium metabisulphite was dissolved in 20 liters of water and added to reactor. pH was adjusted to pH 7 by 50% NaOH solution. After pH adjustment, reactor was heated to 90 °C. During reaction, temperature was controlled at 87-90°C. Mixing was 85 rpm. In addition, two homogenizers were mixing at 1500 rpm. After 40 min reaction time, cooling was started by circulating cold water in the reactor jacket. The activated feather suspension was drained on a fibre cloth in an IBC container. The filtrate was removed and feather was collected into plastic bags. A sample of the filtrate was taken. 300 1 of water and the filtrated feather were added back into the reactor. The pH of the feather suspension was adjusted to pH 2 by 33% HC1. After 5 min mixing time, pH was adjusted to pH 5 by adding 50% NaOH.

After that, feather suspension was drained on a fibre cloth and washed with water. After removal of filtrate, feather was washed with water and drained again on fibre cloth. The feather was left overnight at 16-17 °C on fibre cloth to remove water from it.

Feather was dried by vacuum evaporation in Lödige reactor. Product temperature varied between 21 °C and 27 °C, and the pressure was 24-36 mbar. Samples were taken to follow drying. Total drying time was 5.5 hours. The material was collected into plastic bags. After drying, feather was ground by a conical sieve mill.

20175869 prh 02 -10- 2017

Analysis methods

Before analyses, dried feather sample was cut by a kitchen chipper having a rotating knife to homogenize the sample.

Enzymatic hydrolysability of keratin protein was analysed by hydrolysing modified feather by a commercial proteolytic enzyme mixture Alcalase 2.4L FG (Novozymes, Denmark) at 1% dry matter (DM) content. 2.5 g of feather sample was dissolved in 247.5 ml of 0.05 M sodium phosphate buffer pH 7.5. 50 μΐ of Alcalase was added to start the reaction. Reaction was carried out in Erlenmeyer flasks at 55 °C. Flasks were shaken at 170 rpm for mixing during reaction. Samples were taken during hydrolysis to follow the reaction. Reaction was stopped by adding 1 M HC1 to drop pH below pH 4.0. After 4 h hydrolysis, the remaining solid material was filtered through Whatman 40 filter paper, filter cake dried and weighted, and the degree of solubilisation was calculated. In addition, for 25 μΐ of hydrolysis sample, 2 ml of OPA (o-phtalaldehyde) reagent was added, mixture vortexed and after 2 min incubation in room temperature, the formed absorbance was detected spectrophotometrically by using 340 nm wavelength. The free a-amino-groups in hydrolysed protein react with OPA reagent and form ultraviolet colour and the intensity of the colour was measured. As a reference, untreated, water rinsed feather was hydrolysed and analysed. Analyses were carried out as duplicates.

Nitrogen content in the feather samples was analysed by a Kjeltec analysator based on the Kjeldahl method. Protein content was calculated from the nitrogen content by multiplying by 6.38.

Ash content was analysed by drying the sample at 102 °C for 16 h (Dry matter content) and then heated at 550 °C for 19-22 h.

Total bacteria content of treated feathers was analysed. Feather was mixed thoroughly for 30 min with saline solution and a diluted sample was cultivated on plate count agar plates for 23 days at 30 °C. The formed colonies were calculated and result presented as colony forming units (CFU).

Results and discussion

General remarks from feather treatments

20175869 prh 02 -10- 2017

The aim of the feather treatments was to modify durable and rigid feather keratin by reductive sulphitolysis reaction. Feather was treated with sodium metabisulphite in water solution at 70-90 °C, pH 6.5-7.0 for 40 min. 5% DM content was selected for the experiments to get proper mixing for rather viscous feather suspension throughout the reaction.

In all experiments, already 10 min after the beginning of reaction, the feather suspension started to change and was more freely flowing. The appearance of feather material also changed during treatments. Feather mass absorbed quite much water and the dry matter content after washing (and pressing by scoop) was quite low, approximately 17-19%.

Enzymatic hydrolysability

To determine the effect of sulphitolysis treatments on the digestibility of feather, enzymatic hydrolysability of feather was analysed. The test system consisted of treatment of feather with Alcalase commercial protease for 4 hours. The hydrolysability and hydrolysis result was analysed by two different methods: by hydrolysis residue filtration and by a spectrophotometric method.

Spectrophotometric method was based on the reaction of free amino groups with OPA reagent and the reaction product could be detected by spectrophotometric measurement using 340 nm wavelength. Absorbance measurements showed that the increasing temperature in feather treatment increased the formation of free amino-groups and thus 20 hydrolysis of keratin. In addition, increase in sulphite dosage (from 0.14 up to 0.225g/g DM) also showed some increase in hydrolysability. Result showed that the highest tested sulphite dosage, 0.250 g/g, showed no further improvement in hydrolysability.

Filtration method was applied to determine the amount of feather that could be dissolved by enzymatic treatment. Similarly to spectrophotometric analysis, filtration method showed that 25 increasing temperature in feather modification increased dissolution of feather in enzymatic hydrolysis. The highest dissolution of feather material, 47%, was obtained with large pilot scale experiment at 90 °C. For the untreated feather, the dissolution in hydrolysis was typically 25-26%, but some variations in the dissolution of different feather batches were detected. Especially reference for the experiment at 70°C had 35% dissolution compared to 30 other untreated samples. No significant differences were seen between the treatments at 90 °C with 0.225 and 250 g/g sulphite dosages. Based on the hydrolysis results, 90 °C, pH 7.0 and sulphite dosage of 0.225 g/g DM was selected for large pilot scale experiment.

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Protein, ash and bacteria contents

Protein content was analysed for modified feather after different treatments and for untreated feather. For untreated feather, protein content was analysed to be 93% of DM whereas for treated feather 92-95%. Thus only small changes in protein content were caused by feather modification treatments.

Ash content, i.e. mineral content, was analysed from feather, filtrates and washing waters to assure that added sulphite reagent and other salts formed in pH adjustments are adequately removed by the washing procedure. In ash analysis, the modified feathers typically showed yellowish residue indicating that ashing was not fully complete although longer heating times were also tested. Thus, the presented ash content values for modified feathers might be higher than the true value. The ash content for untreated feather was 2.7% whereas for modified feathers 0.1-1.3%. Thus, results showed that untreated feather had higher ash content than all the modified feather samples. The first filtrates i.e. the sulphite solution separated from feathers after reaction, contained naturally increasing amounts of ash with increasing added sulphite. The last washing water for all experiments contained ash only 00.1%. Thus the washing procedure carried out was adequate for removal of salts.

Sodium metabisulphite is an antimicrobial substance and is used as food preservative and therefore it was likely that the bacteria content of modified feather samples was low. Even though feather was treated and handled in a normal laboratory room, the analysed bacteria content was very low, below the detection limit 40 CFU/g of feather DM. The result indicates good microbiological quality.

Modification process

Based on the experiments, a process for feather treatments was developed (Figure 1). Preferred process consists of sulphitolysis, pH adjustments, filtration and washing steps as well as milling and drying of feather material.

Sulphitolysis preferably includes the reaction of feather in 5 % DM content with sodium metabisulphite dosage of 0.225 g/g DM at 90 °C, pH 7 for 40 min. The first filtration (Figure 1) is carried out to remove the unreacted sulphite so that it can be recycled. In addition, the sulphite rich washing water could potentially be recycled and reused, and could replace partly the rather high initial sulphite dosage.

20175869 prh 02 -10- 2017

REFERENCES

Cited patent document:

EP 1731528

EP 0499260

EP 2832236

US 20120219667

US 20150152153

WO 03011894

Cited scientific articles:

Gomez-Estaca, J., Gavara, R., Catalä, R., Hernandez-Munoz, P., 2016. The Potential of Proteins for Producing Food Packaging Materials: A Review. Packag. Technol. Sci. 29, 203224

Khosa, M.A., Ullah, A., 2013. A sustainable role of keratin biopolymer in green chemistry: a review. J. Food Processing & Beverages 1 (1) 1-8.

Pedersen, M.B., Yu, S., Plumstead, P., Daalsgaard, S., 2012. Comparison of four feed proteases for improvement of nutritive value of poultry feather meal. J. Anim. Sci. 90, 350352.

Staron, P., Banach, M., Kowalski, Z., Staron, A., 2014. Hydrolysis of keratin materials derived from poultry industry. ECOpole'13 Conference, Jarnoltowek, 23-26.10.2013. Proceedings of ECOpole 8 (2) 443-448.

Claims

PATENTTIVAATIMUKSET

1. Menetelmä höyhenraaka-aineen muuntamiseksi, joka menetelmä käsittää vaiheet:A process for converting a feather raw material comprising the steps of:

(a) käsitellään höyhenraaka-aine sulfiitti-ioneja sisältävässä ensimmäisessä vesipitoisessa liuoksessa, jossa käsittely suoritetaan pH:ssa 6-8, saavuttaen noin 90(a) treating the feather raw material in a first aqueous solution containing sulfite ions, wherein the treatment is carried out at pH 6-8, reaching about 90

5 °C lämpötilan, käsittelyn kestäessä ainakin 30 min;5 ° C, treatment time of at least 30 min;

(b) erotetaan vaiheesta (a) saatu sulfonoitu höyhenraaka-aine;(b) separating the sulfonated feathers obtained from step (a);

tunnettu siitä, että menetelmä käsittää lisäksi vaiheet:characterized in that the method further comprises the steps of:

(c) käsitellään sulfonoitu höyhenraaka-aine toisessa vesipitoisessa liuoksessa, jolloin käsittely suoritetaan pH:ssa 1,5-3,0 ja lämpötilassa 10-30 °C, käsittelyn kestäessä(c) treating the sulfonated feather raw material in a second aqueous solution, the treatment being carried out at a pH of 1.5 to 3.0 and at a temperature of 10 to 30 ° C for a duration of treatment.

10 ainakin 5 minuuttiapa (d) säädetään toisen vesipitoisen liuoksen tai toisesta vesipitoisesta liuoksesta saadun höyhenraaka-aineen pH ainakin pH:ksi 4,5-5,5.10 for at least 5 minutes (d), adjust the pH of the second aqueous solution or the feathers obtained from the second aqueous solution to at least pH 4.5-5.5.

2. Patenttivaatimuksen 1 mukainen menetelmä tunnettu siitä, että menetelmä lisäksi käsittää vaiheen:A method according to claim 1, characterized in that the method further comprises the step of:

15 (e) erotetaan vaiheesta (d) saatu höyhenmateriaali.(E) separating the feather material obtained from step (d).

3. Patenttivaatimuksen 2 mukainen menetelmä tunnettu siitä, että menetelmä lisäksi käsittää vaiheen:A method according to claim 2, characterized in that the method further comprises the step of:

(f) märkäjauhetaan vaiheesta (e) saatu höyhenmateriaali.(f) wet milling the feather material obtained from step (e).

4. Patenttivaatimuksen 3 mukainen menetelmä tunnettu siitä, että menetelmä lisäksiThe method according to claim 3, further comprising

20 käsittää vaiheen:20 comprises the step of:

(g) kuivataan vaiheesta (f) saatu höyhenmateriaali muunnetun höyhenjauheen valmistamiseksi.(g) drying the feather material from step (f) to produce a modified feather powder.

5. Patenttivaatimuksen 4 mukainen menetelmä tunnettu siitä, että vaiheesta (f) saatu höyhenmateriaali altistetaan entsymaattiselle hydrolyysille ennen kuivausvaihetta5. A method according to claim 4, characterized in that the feather material obtained from step (f) is subjected to enzymatic hydrolysis prior to the drying step.

25 (g).25 (g).

6. Patenttivaatimuksen 1 tai 2 mukainen menetelmä tunnettu siitä, että vaiheesta (e) saatu höyhenmateriaali kuivataan ensin ja sitten jauhetaan kuivana jauheen valmistamiseksi.Method according to claim 1 or 2, characterized in that the feather material obtained from step (e) is first dried and then ground dry to produce a powder.

20175869 prh 21 -03- 201920175869 prh 21 -03-20199

7. Jonkin edellisen patenttivaatimuksen 1-6 mukainen menetelmä tunnettu siitä, että vaiheeseen (a) annettu mainittu höyhenraaka-aine on silputtuja tai jauhettuja höyheniä, edullisesti silputtuja tai jauhettuja kananhöyheniä.A method according to any one of claims 1 to 6, characterized in that said feather feedstock to step (a) is chopped or minced feathers, preferably chopped or minced chicken feathers.

8. Jonkin edellisen patenttivaatimuksen 1-7 mukainen menetelmä tunnettu siitä, ettäA method according to any one of claims 1 to 7, characterized in that

5 ensimmäinen vesipitoinen liuos sisältää sulfiittimäärän, joka vastaa 0,15-0,25 g metabisulfiittia / g höyhenraaka-ainetta (kuiva-aine).The first aqueous solution contains an amount of sulphite corresponding to 0.15-0.25 g of metabisulphite / g of feathers (dry matter).

9. Jonkin edellisen patenttivaatimuksen 1-8 mukainen menetelmä tunnettu siitä, että vaiheessa (c) toinen vesipitoinen liuos on vettä.Process according to any one of claims 1 to 8, characterized in that in step (c) the second aqueous solution is water.

10. Jonkin edellisen patenttivaatimuksen 1-9 mukainen menetelmä tunnettu siitä, ettäA method according to any one of claims 1 to 9, characterized in that

10 useita höyhenenä kerätään vaiheessa (b) ja käsitellään seuraavaksi vaiheessa (c).The plurality of feathers 10 are collected in step (b) and subsequently processed in step (c).

11. Jonkin edellisen patenttivaatimuksen 1-10 mukainen menetelmä tunnettu siitä, että vaiheessa (b) saatu sulfiittirikas vesi kierrätetään ja käytetään uudestaan vaiheessa (a) osittain korvaamaan alkuperäistä sulfiittiannostusta vaiheessa (a).The process according to any one of claims 1 to 10, characterized in that the sulfite-rich water obtained in step (b) is recycled and reused in step (a) to partially replace the original sulfite dosage in step (a).

12. Jonkin edellisen patenttivaatimuksen 1-11 mukainen menetelmä tunnettu siitä,Method according to one of the preceding claims 1 to 11, characterized in that:

15 että mikä tahansa vaiheista (b), (c) ja (e), käsittää edelleen pesuvaiheita.15 that any of steps (b), (c) and (e) further comprises washing steps.

13. Jonkin edellisen patenttivaatimuksen 1-12 mukainen menetelmä, jossa erotteluvaiheet (b) j a (e) suoritetaan suodattamalla.The process according to any one of claims 1 to 12, wherein the separation steps (b) and (e) are performed by filtration.

14. Jonkin edellisen patenttivaatimuksen 1-13 mukainen menetelmä tunnettu siitä, että reaktiolämpötilaa vaiheessa (a) säädetään 87-90 °C:ssa.Process according to any one of claims 1 to 13, characterized in that the reaction temperature in step (a) is controlled at 87-90 ° C.

20 15. Jonkin edellisen patenttivaatimuksen 1-14 mukainen menetelmä tunnettu siitä, että mainitut sulfiitti-ionit mainitussa ensimmäisessä vesipitoisessa liuoksessa ovat lisätystä natriumsulfiitista Na2SC>3, natriumvetysulfiitista NaHSCl· tai natriummetabisulfiitista Na2S20s.A process according to any one of claims 1 to 14, characterized in that said sulfite ions in said first aqueous solution are Na 2 SO 3, sodium hydrogen sulphite, NaHCO 3 sodium, or sodium metabisulphite Na 2 SO 2 S.

16. Jonkin edellisen patenttivaatimuksen 1-15 mukainen menetelmä tunnettu siitä,Method according to one of the preceding claims 1 to 15, characterized in that:

25 että höyhenraaka-aineen kuiva-ainepitoisuus ensimmäisessä vesipitoisessa liuoksessa on välillä 5-15 % (p/p).25 that the dry matter content of the feather raw material in the first aqueous solution is between 5 and 15% (w / w).

17. Proteiinirikas muunnettu höyhentuote, joka on valmistettu patenttivaatimuksen 4 mukaisella menetelmällä, tunnettu siitä, että mainittu tuote käsittää A protein-rich modified feather product made by the process of claim 4, characterized in that said product comprises

20175869 prh 21 -03- 2019 höyhenmateriaalijauhetta, jonka proteiinipitoisuus on yli 90 % ja tuhkapitoisuus alle 1,5 %, ja jolloin mainittu tuote ei ole proteaasikäsitelty.20175869 prh 21 -03-20199 powdered feathers with a protein content of more than 90% and an ash content of less than 1,5%, the said product being not protease-treated.

18. Patenttivaatimuksen 17 mukainen proteiinirikas muunnettu höyhentuote, tunnettu siitä, että mainitulla höyhenmateriaalijauheella on korkeampi entsymaattinenProtein-rich modified feather product according to claim 17, characterized in that said feather powder has a higher enzymatic

5 hydrolysoituvuus verrattuna käsittelemättömään höyhenmateriaaliin.5 hydrolysis compared to untreated feathers.

19. Ravintolisäaine tunnettu siitä, että mainittu lisäaine käsittää tai koostuu patenttivaatimuksen 17 tai 18 mukaisesta proteiinirikkaasta muunnetusta höyhentuotteesta.19. A nutritional supplement characterized in that said additive comprises or consists of a protein rich modified feather product according to claim 17 or 18.

20. Eläinrehu tunnettu siitä, että mainittu eläinrehu käsittää patenttivaatimuksen 19Animal feed characterized in that said animal feed comprises claim 19

10 mukaisen ravintolisäaineen.10 nutritional supplement.

21. Elintarviketuote tunnettu siitä, että mainittu tuote käsittää patenttivaatimuksen 19 mukaisen ravintolisäaineen.A food product characterized in that said product comprises a nutritional supplement according to claim 19.

22. Kosmetiikkalisäaine tunnettu siitä, että mainittu lisäaine käsittää tai koostuu patenttivaatimuksen 17 tai 18 mukaisesta proteiinirikkaasta muunnetusta22. A cosmetic additive characterized in that said additive comprises or consists of a protein rich modification according to claim 17 or 18.

15 höyhentuotteesta.15 feather products.

23. Kosmetiikkatuote tunnettu siitä, että mainittu tuote käsittää patenttivaatimuksen 22 mukaisen kosmetiikkalisäaineen.A cosmetic product characterized in that said product comprises a cosmetic additive according to claim 22.

24. Pakkausmateriaalilisäaine tunnettu siitä, että mainittu lisäaine käsittää tai koostuu patenttivaatimuksen 17 tai 18 mukaisesta proteiinirikkaasta muunnetustaPackaging material additive characterized in that said additive comprises or consists of a protein rich modification according to claim 17 or 18

20 höyhentuotteesta.20 feather products.

25. Pakkausmateriaali tunnettu siitä, että mainittu materiaali käsittää patenttivaatimuksen 24 mukaisen lisäaineen.Packaging material characterized in that said material comprises an additive according to claim 24.

26. Pinnoite- tai rakennusmateriaalin lisäaine tunnettu siitä, että mainittu lisäaine käsittää tai koostuu patenttivaatimuksen 17 tai 18 mukaisesta proteiinirikkaasta26. Coating or building material additive characterized in that said additive comprises or consists of a protein rich according to claim 17 or 18.

25 muunnetusta höyhentuotteesta.25 modified feathers.

27. Patenttivaatimuksen 26 mukainen lisäaine tunnettu siitä, että mainittu pinnoite tai rakennusmateriaali on sementti tai maali.An additive according to claim 26, characterized in that said coating or building material is cement or paint.

28. Pinnoite- tai rakennusmateriaali tunnettu siitä, että mainittu materiaali käsittää patenttivaatimuksen 26 tai 27 mukaisen lisäaineen.A coating or building material, characterized in that said material comprises an additive according to claim 26 or 27.

29. Patenttivaatimuksen 17 tai 18 mukaisen proteiinirikkaan muunnetun höyhentuotteen käyttö ravintolisäaineena, kosmetiikkalisäaineena,Use of a protein rich modified feather product according to claim 17 or 18 as a nutritional supplement, as a cosmetic supplement,

5 pakkausmateriaalinsäaineena tai lisäaineena pinnoite- tai rakennusmateriaaleille.5 as packaging material or as an additive to coating or building materials.