WO1980001351A1

WO1980001351A1 - Ruminant feeds from bagasse

Info

Publication number: WO1980001351A1
Application number: PCT/US1979/001116
Authority: WO
Inventors: F Andrews
Original assignee: Brewer Co Ltd
Priority date: 1978-12-26
Filing date: 1979-12-21
Publication date: 1980-07-10

Abstract

A process and a product made from the process for making ruminant feeds from cellulosic material. The cellulosic material is first conditioned to provide a particle of from about 1 inch (2.54 cm) wide, about 2-1/2 inches (6, 35 cm) long and 3/8 inch (0.9525 cm) thick. The conditioned cellulosic material is mixed with a hydrolyzing media and hydrolyzed under basic or acidic hydrolyzing conditions. During the hydrolysis step the cellulosic material is degraded into fibers of from about cellulosic material is degraded into fibers of from about 3/8 to about 1-1/4 inches (0.9525 - 3.175 cm). During the hydrolysis the material is agitated under mild agitation sufficient to bring about complete hydrolysis but prevent further degradation of fiber size. Following the hydrolyzing step the hydrolyzed cellulosic material is separated from the hydrolyzing media and washed to remove any remaining basic or acidic hydrolyzing media. The pH of the hydrolyzed cellulosic material is then adjusted to about 4 to about 6. The hydrolyzed cellulosic material is then mixed with feed additives to enhance the properties of the cellulosic material as a feed product. The mixture of hydrolyzed cellulosic material and feed additives is thoroughly mixed and dried to reduce moisture content. The mixture is then cubed or pelletized for use as a feed product. Additionally, vitamin supplements and mineral supplements can be added during the cubing and pelletizing steps for further enhancing the feed value of the product.

Description

RUMINANT FEEDS FROM BAGASSE

Background of the Invention

The ever increasing demand for food by an ever increasing world population requires the utmost efficiency in food production techniques. Feeding ruminants grains which could be consumed by humans is an inefficient use of such grains in consideration of the millions of people in underdeveloped nations who suffer from malnutrition and die from starvation yearly. Work has been performed to transform cellulosic material, which is undigestible by human beings but which can be digested by ruminants, into a feed for the ruminants and thus free grains which are to be fed to ruminants and thereby make such grain available as a food source for humans.

Bergius, in the early 1930's, discovered that cellulose could be chemically degraded to an alcohol by hydrolysis with acid or alkali. The decomposition products are dependent upon the acid or alkali used in the hydrolysis, the particle size of the cellulosic material, the temperature, the pressure and length of time of the hydrolysis reaction. If a concentrated acid or alkali is used, a fine particle size is formed upon hydrolysis. The hydrolysis reaction required shorter reaction times when conducted at higher temperatures and higher pressures.

Depending upon the hydrolyzing agent, acid or alkali, a partial hydrolysis of ceilulosic material yields alpha, beta, or gamma cellulose. Through a highly complex chain of chemical reactions, the lignin present in ceilulosic materials can be removed by an alkali hydrolysis and the pentosans present can be removed by acid hydrolysis. Lignin is the chemical name given to an unclassified group of highmolecular weight substances whose exact nature is not known, but which are assumed to bind or hold cellulose or hemicellulose together. They are composed of aromatic benzene rings which contain some methylated phenolic groups. The effect of caustic hydrolysis on lignin is not known but it is believed that the caustic does not remove lignin but merely reduces its ability to bind or hold cellulose or hemicellulose together. If the cellulose is not bound so tightly, it is more digestible for animals. An important source of cellulose material is the refining of sugar from sugarcane. After the sugar has been extracted from the sugarcane plants, the remaining plant material is a ceilulosic material which is called bagasse. In the normal operation of a sugar mill, about 70 percent of the bagasse produced is burned in the boilers of the sugar mill for generation of process steam and electricity. The remainder of the bagasse generated is considered as a waste product and its conversion to a valuable by-product would be highly desirable. Leftover bagasse, in its natural state after exiting a sugar mill, has been used as an animal feed. There are, however, several deficiencies which reduce the value of bagasse as an important source of feed for ruminant animals. For example, bagasse has a high lignin content and ruminants cannot beneficially digest lignin found in bagasse. The high lignin content also retards the digestion of other ceilulosic materials which may be ingested by the ruminants. Bagasse also contains a negligible amount of protein, generally, on the order of 1 to 3 percent by weight of the bagasse. Bagasse fibers can also be too coarse for good digestion or so fine that they pass through the ruminant's stomach too quickly. If passage of the fiber occurs too quickly, the fibers cannot retain other foodstuffs of value to the ruminant. Retention of other food values is part of the digestive function of fiber. Bagasse in its natural state is generally too hard and coarse for good digestion. The sharp fibers present in bagasse can .pierce stomach walls and cause internal bleeding if not macerated by the animal to an extent which destroys such sharp edges. Bagasse does contain some important trace elements like calcium, chromium, and potassium, but it lacks essential vitamin complexes such as vitamins A and B complexes.

The fibrous fraction of sugarcane bagasse, like other ligno-cellulosic materials (examples, wood, bamboo, etc.) contain as primary constituents cellulose, lignin, and hemicelluloses. The latter include both pentosans and hexosans in amounts of about 28 weight percent total hemicellulose which average about 12 weight percent pentosans (about 90 to 95 weight percent xylan) and about 16 weight percent hexosans on a dry weight basis in a typical bagasse. The large amount of lignin in sugarcane and bagasse, ranging from about 20 to 22 percent on a dry weight basis, destroys much of the value of the bagasse as an animal feed as the lignin interferes with the digestion of cellulose and other foodstuffs in the rumen of the animal. Summary of the Invention

A process for making ruminant feeds from ceilulosic material is disclosed. The process comprises the steps of shredding the ceilulosic material to a particle size of less than about 1 inch (2.54 cm) wide, about 2-1/2 inches (6.35 cm) long and about 3/8 inch (0.9525 cm) thick. The sized ceilulosic material is hydrolyzed in an acid or alkaline hydrolyzing media under hydrolyzing conditions with agitation sufficient to provide thorough mixing and maintain fiber length of the cellulose material of from about 3/8 (0.9525 cm) to about 1-1/4 inches (3.175 cm). The hydrolyzed cellulose particles are separated and washed for removing excess acid or alkaline hydrolyzing media. The collected hydrolyzed cellulose is washed and the pH is adjusted to a range of from about 4 to about 6. Feed additives are then mixed with the hydrolyzed cellulose. The feed additives added are selected from the group consisting of soybean meal, cottonseed meal, urea, calcium phosphate, filter mud from sugar mills, molasses, water and mixtures thereof. The hydrolyzed cellulose and feed additives are then thoroughly mixed and dried to a moisture content of from about 2 to about 4 percent less than the desired moisture content of the final feed product. The dried mixture is then pelletized or cubed to provide the final feed product. Additional water can be added during the cubing or pelletizing steps to enhance the cubing or pelletizing properties of the mixture and to raise the moisture content of the final feed cubes or pellets to the desired moisture level. Simultaneously, with the cubing or pelletizing of the mixture, there can be added vitamin supplements, such as the vitamin complexes A, B, C, D and E. The protein value of the feed can be increased by adding a high protein value plant material such as taro, manioc, cassava, tapioca and other natural protein-containing materials or high protein substances such as cottonseed meal and soybean meal. An exemplary ruminant animal feed produced by the process and suitable for feed for ruminants can contain at least about 50 parts by weight hydrolyzed cellulose, up to about 10 parts by weight urea, up to about 2.5 parts by weight calcium phosphate and up to about 30 parts by weight molasses. The various feed additives generally comprise up to about 50 parts by weight of the final feed product.

A ruminant animal feed can also be made from taro, cassava and tapioca plants. To make such a ruminant animal feed the plants are shredded, chopped and washed. The chopped plants are then sized for a suitable size for a ruminant feed, such as particles up to about 1-1/2 inches (3.81 cm) in the greatest dimension. The sized plants are then dried at a temperature below the charring temperature to a moisture content of about 5 percent by weight. Alternatively, the chopped and sized plants can be boiled in water for up to about 10 minutes, drained and then dried to a moisture content of about 5 to about 10 weight percent. The dried plants, rich in natural protein, can be used as a ruminant animal feed or can be added to feed as a feed supplement.

Brief Description of the Drawings

FIG.1 illustrates a schematic outline and arrangment of equipment for carrying out the process of this invention; FIG. 2 is a graph of the average daily milk production of dairy cattle fed a hydrolyzed cellulose feed made by the process of the invention;

FIG. 3 is a graph of the butterfat content of milk produced by dairy cattle fed a hydrolyzed cellulose feed made by the process of this invention; and FIG. 4 is a graph of the non-butterfat solids of milk produced as depicted in FIG. 3.

Detailed Description of the Invention

The process of this invention produces an animal feed for ruminant animals from a cellulose material. Any cellulose material can be used in the process, such as rice hulls, cottonseed hulls, cane trash (leafy portion of sugarcane), nut hulls (such as almond hulls), wood particles, corn stalks, corncobs and the like. However, it is a preferred practice to use sugarcane bagasse resulting from the refining of sugarcane. The process is herein described with reference to

FIG. 1. If the cellulose material to be treated by this process is other than sugarcane bagasse, it may have to be shredded in a shredder 10. Generally, mill run bagasse, which is the fibrous waste of sugarcane after the majority of the sugar has been extracted, is of sufficiently small size that it does not require further shredding. The cellulose material is shredded, chopped, or cut to physically and mechanically break down the long cellulose fibers present in such cellulose material. The shredded cellulose material is then screened in screen 12. In the screen 12 the cellulose material is separated into three fractions. The particles greater than the preferred range are discarded or preferably recycled to the shredder. The particles, having dimensions less than about 1 × 2-1/2 × 3/8 inches (2.54 × 6.35 × 0.9525 cm) but greater than the fines, are retained for further processing. For purposes of this process, fines are considered to be those particles which pass through a 100 mesh sieve. The fines can be discarded because such small particles in ruminant animal feeds can inhibit digestion and interfere with the rumination process. Further, if the feed is for dairy cattle, the fines contribute to low fat content in the milk. Generally, the fines are comprised of substantially hemicellulose which can be used for other purposes, such as special purpose feeds. Alternatively, the fines can be fed to the mixer 28 where some of the fines can be mixed into the finished product mix prior to drying and agglomerating in the cuber 36 to make such a special purpose feed. Cellulose material particles of greater than 100 mesh and less than about 1 inch (2.54 cm) wide, about 2-1/2 inches (6.35 cm) long and about 3/8 inch (0.9525 cm) thick are preferred for use in the subsequent hydrolysis reaction under the conditions hereinafter disclosed. During the hydrolysis step there is further diminution of the particle size but this initial particle size is sufficiently large to prevent formation of particles upon hydrolysis that are too small for utility as a ruminant animal feed. For example, the length of the fiber in a ruminant animal feed is preferably greater than about 3/8 of an inch (0.9525 cm) to about 5/8 inch (1.5875 cm) in order to prevent digestive problems in the animals and low fat in dairy cow's milk. Further, the preferred initial range of cellulose particle sizes is sufficiently small as to provide upon hydrolysis an end particle size that can be easily ingested and digested by the ruminant animal for which the feed is intended.

Following the screening and sizing of the cellulose material, it is fed into the hydrolysis reactor 16. In the hydrolysis reactor the cellulose material is partially hydrolyzed for removal of a substantial proportion of the lignin contained in the cellulose. Generally, the lignin content in sugarcane bagasse is from about 20 to 22 percent by weight. Ruminant animals are unable to digest lignin and lignin interferes with the digestion of cellulose and other foodstuffs in the rumen. The hydrolysis is conducted under conditions sufficient to prevent loss of pentosans which are also found in cellulose material. Pentosans are an important energy source and it is, therefore, desirableto retain the pentosans in the final feed produced, the hydrolysis step is, therefore, conducted under hydrolyzing conditions such that there is a substantial reduction in the lignin content of the cellulose material without destroying the pentosan. content. An important discovery in using the feed produced from the present process is that it is not necessary to completely remove lignin from the hydrolyzed cellulose material which is to be used as a ruminant feed. For example, lignin is present in almost everything ruminant animals generally eat. Alfalfa, a long used feed for ruminants, contains as much as 7 to 10 percent lignin. Thus, ruminant animals, such as cattle, can tolerate a certain amount of lignin without seriously impairing the digestibility of rumen feedstuffs. The amount of lignin which can be present in ruminant feeds is directly related to the acid detergent value of the feed. Ruminant animals can tolerate an acid detergent fiber to lignin ratio of at least about 4 to 1. Acid detergent fiber (ADF) is a system of stating the crude fiber content of a feed. Prior to the use of ADF, analysis of animal feed was. stated in terms of crude fiber content to designate the cellulose content of the feed. Chemically, the crude fiber method is a measure of the residue which remains after a weak acid and weak alkali are boiled with cellulose. Crude fiber is used as a measure of the bulk or roughage in feeds or as a rough indication of the undigestible portion of the feed. This system of analysis overlooks the fact that in about one case out of four, the digestibility of the crude fiber exceeds the fraction containing sugar and starches. The acid detergent fiber method is an improvement over the crude fiber analysis. The approach of the acid detergent fiber method is to remove the hemicelluloses (pentosans) and the soluble and digestible components of the feed leaving only lignin and cellulose. It is, thereby, possible to determine the lignin value of a given feed by use of a modified ADF analysis. By then subtracting the lignin value from the determined ADF value, it is possible to derive the cellulose value. The neutral detergent fiber (NDF) method is another method for determining the cellulose value for a given animal feed. The neutral detergent fiber method solubilizes lipids and proteins, removes minerals, gelatinizes starches at a neutral pH to prevent hydrolysis of the hemicelluloses and isolates the cell walls containing cellulose and lignin. The neutral detergent fiber method allows the pentosans to be calculated by subtracting the acid detergent fiber value from the neutral detergent fiber value (NDF - ADF = pentosans).

The hydrolysis step conducted in the process of this invention is critical. The hydrolysis is conducted under hydrolyzing conditions such that the cellulose material is partially hydrolyzed to produce at least a 4 to 1 ADF to lignin ratio in the final feed product and retain a satisfactory effective fiber length of at least about 3/8 inch (0.9525 cm) for the final feed product.

The hydrolysis can be conducted using either an acid hydrolysis or an alkaline hydrolysis. For acid hydrolysis any strong inorganic acid can be utilized as the hydrolyzing agent. For example, acids which can be used include hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid and the like. When an alkaline hydrolysis is conducted, the alkaline hydrolyzing agent can be selected from any strong concentrated base, such as sodium hydroxide, ammonium hydroxide and the like.

It is the preferred practice of this invention that hydrolysis be conducted using an alkaline hydrolyzing agent Alkaline hydrolysis is preferred because it provides an increase in acid detergent fiber and reduction of lignin content without substantial loss of the pentosans. Particularly preferred is the use of ammonium hydroxide as the hydrolyzing agent. Ammonium hydroxide is preferred because the ammonia formed upon dissociation can react with cellulose derivatives forming amino glucoside complexes which behave as, or, are natural protein compounds. Such natural protein compounds are more digestable by ruminant animals than urea added to a feed. Acid hydrolysis provides a smaller increase in crude fiber, ADF and NDF values, and a decrease in pentosans, while the lignin values remain substantially equivalent to those values found in untreated bagasse. There is also a higher recovery of usable fiber using alkaline hydrolysis than when acid hydrolysis is utilized.

When an alkaline hydrolyzing agent is utilized, the concentration of the alkaline hydrolyzing agent can be up to 20 percent by weight alkaline compound in water. It is particularly preferred to use concentration of up to about 5 percent alkaline solution because such a concentration yields the greatest increase in crude fiber, ADF and NDF values, while substantially decreasing the percentage of lignin during a relatively short reaction time of about 30 minutes or less. The use of a concentration of up to about 5 percent alkali results in retention of about half of the pentosans which provide an important energy source when left in the food.

The hydrolysis step is conducted in a hydrolysis reactor which is fitted with means for providing heat to the reactor. Such means can include direct heating means or the reactor can be jacketed, such as with a steam jacket or hot water jacket for providing the necessary heat for hydrolysis. The reactor is also equipped with means for providing agitation to the material in the reactor. For example, as shown in FIG. 1, such means for agitating the cellulose material and hydrolyzing agent can be an air sparger. Such means for agitation can also be a mechanical stirring device or other mechanical agitation means. Agitation of the reaction mixture is critical for the proper hydrolysis and production of hydrolyzed cellulose material to be used as ruminant feed. Rapid agitation of the reaction material breaks down the cellulose in the material to micron particle sizes. For the reasons stated above, it is important to maintain the fibers as long as possible and, therefore, slow agitation is desirable. For example, when a mechanical stirrer is used to provide agitation to the reaction mixture, such a stirrer is rotated at about 5 to 10 rpms depending on the reactor size, but is generally maintained at a sufficiently slow speed to keep the bagasse moving to insure uniform hydrolysis. When an air sparger is used for agitation at the bottom of the reaction vessel, air is generally introduced at about 3 to 4 standard cubic feet per minute (scfm) (0.084951 to 0.113268 cubic meters per minute) per 10 cubic feet (0.28317 cubic meters) of reactor volume to insure uniform hydrolysis without destroying the fiber length.

The hydrolysis reaction is conducted at a temperature from about 200° to about 280°F (93-138°C) for a time period up to about 90 minutes. It is preferred that the hydrolysis reaction be conducted at a temperature from about 214° to about 250°F (101-121°C). Such a temperature can be achieved by direct heating of the reaction vessel or by supplying the heat, such as with superheated steam through a jacket on the outside of the reactor. When superheated steam is utilized in a jacketed reactor, the superheated steam is at about a temperature of 400°F (205°C) and a pressure of 100 psi (7.031 kgkm²). The hydrolyzing media used in the preferred practice of the invention is an alkaline solution comprising three components. The alkaline solution comprises fresh alkaline solution from tank 18, recycled and reconstituted alkaline solution from tank 21 and water. The water is added to adjust the pH within the range from about 12 to 13 and to maintain the desired boiling point.

The desired end point of the hydrolysis reaction can be determined by monitoring the reaction time for hydrolysis if the concentration of the alkaline solution is maintained constant and the quantity of cellulose material is controlled. The end point can also be determined by chemical analysis of crude fiber, ADF and lignin. Upon hydrolysis, the cellulose material being hydrolyzed forms a reaction mixture which becomes darker as the hydrolysis reaction progresses. The end point can also be determined by noting the color of the reaction mixture, the texture of the coarser cellulose material, and physically noting the softness of the cellulose material.

When the hydrolysis reaction has been completed as determined by time, chemically or visually, the contents of the reactor are dropped from the hydrolysis reactor into a means for separating the hydrolyzed cellulose material from the hydrolysis media. Such means for separating the solid cellulose material from the liquid media can be any suitable solids/liquids separation apparatus, such as a filter, sequential centrifuges, filter press, centrifuge, dewatering press and the like. In FIG. 1 a centrifuge 22 is shown wherein the excess hydrolyzing agent is separated from the hydrolyzed cellulose material. The excess hydrolyzing agent is pumped to the holding tank 23 or can be pumped directly to the evaporator 20. Fresh water is used to wash the alkaline hydrolyzing agent from the cellulose material cake in the centrifuge. Dilute hydrochloric acid from vessel 24 can be used to return the pH of the cellulose material cake to about 4 to 5. If the hydrolysis reaction is conducted under acidic conditions, then the cellulose material separated in the centrifuge 22 is washed with a dilute basic solution such as dilute sodium hydroxide to also return the pH of the bagasse cake to about 4 to 6. The excess hydrolyzing agent removed from the cellulose material can be recycled to reactor 16 from the centrifuge 22 to the evaporator 20 and to recycle tank 21. In the evaporator 20 the hydrolyzing agent can be reconstituted and transferred to a recycle tank 21 for recycling to the hydrolysis reactor 16 for further use in a subsequent hydrolysis reaction. By reconstituting and recycling the excess hydrolyzing agent, there is a conservation of the amount of hydrolyzing reagent required in the process. In addition, by recycling the hydrolyzing agent there is no appreciable loading, either of an acid or a base, on the waste stream for a plant utilizing this process.

From the centrifuge 22 the hydrolyzed cellulose material is transferred to a storage hopper 26. The cellulose material is stored in such a hopper until it is to be formed into the final feed.

From the storage hopper 26 the hydrolyzed cellulose is fed into a mixing chamber 28. In the storage hopper 26 or the mixer 28 additional material can be added to increase the food value of the hydrolyzed cellulose. For example, feed additives that can be added can be selected from the group consisting of filter mud from a sugar mill, soybean meal, cottonseed meal, flavorings, nutritional additives, molasses, urea, water and mixtures thereof. In addition to adding urea, or as replacement therefor, natural protein material such as taro, manioc, cassava, tapioca and the like can be added to the hydrolyzed cellulose to increase the protein value of the cellulose material as feed. Urea, while a good source of nitrogen for protein, is limited in the amount that can safely be added to a ruminant animal's diet. Usually, the use of urea is restricted to about one-third of the protein nitrogen in a ruminant's total ration. If more than this amount is added, the animal cannot utilize the protein efficiently. In extreme cases of too much urea, an animal may die of urea toxicity. While urea is a convenient method of adding a limited amount of crude protein, it is relatively expensive. Taro and other substances containing a high percentage of natural protein offer inexpensive substitutes. For example, taro has the following general composition:

Taro Dry Basis

Weight %

Item Stems Leaves Corms

Crude Protein 7.4 29.2 4.5

Crude Fiber 15.5 14.5 6.0

Ash 13.8 11.8 3.5 Acid Detergent Fiber 27.6 31.6 7.1

Lignin 6.9 9.9 1.8

Neutral Detergent Fiber 27.6 38.8 38.2

Pentosans -0- 7.3 31.1

Calcium 0.5 1.5 0.16 Phosphorus 2.6 .35 0.15

Magnesium 1.1 .18 0.12

Potassium 7.4 4.8 1.73

Total Sugars as Invert 57.8 19.4 7.0

Taro contains an undesirably large amount of calcium oxalate which gives it such a bitter taste that most ruminants refuse to eat it as a feed or feed additive. To eliminate the bitter taste and make it palatable as a feed, taro leaves, stems and corms can be prepared in either of two methods. First, taro can be washed, chopped to suitable size, such as up to about 1-1/2 inches (3.81 cm) in their greatest dimension, and dried at a temperature below its charring point to a moisture content of about 5 percent. Then, it can be blended with other nutritional supplements and fed to a cuber which uses molasses as a binding agent if the taro is to be the basic feed stock. Or secondly, the taro is washed, chopped and sized. The sized taro is boiled in water for up to about 10 minutes, drained and added to the mixing chamber 28 for blending with the hydrolyzed cellulose material. The amount of water used is held to a minimum to prevent the over-leaching of protein from the taro. The weight of the natural protein containing material added to the hydrolyzed cellulose depends upon the amount of protein in such material and the amount of natural protein desired in the finished feed. Generally, taro (leaves and stems) should be added to the hydrolyzed cellulose material in a range up to about 75 percent of the dry weight of the final feed.

The above-described feed additives are blended into the hydrolyzed cellulose to keep the crude fiber, ADF value, NDF value, protein, fat and ash at the desired levels for the final feed product. Additionally, minerals such as calcium phosphate can be added from the mixing tank. The feed additives to be added in the mixing chamber 28 can be fed from holding tank 34 into a mixing tank 30. In the mixing tank 30 the additives are thoroughly mixed and from the mixing tank 30 are fed into the mixing chamber 28 to be mixed with the hydrolyzed cellulose. In the mixing tank 30, for example, a mixture of urea, calcium phosphate and molasses can be diluted with a sufficient amount of water to allow the mixture to be .sprayed into the mixing chamber 28. The amounts of urea, calcium phosphate and molasses can vary from about 1 to about 12 pounds (0.454 to 5.443 kg), 0.5 to about 3.0 pounds (0.227 to 1.361 kg) and 5 to 30 pounds (2.268 to 13.608 kg) respectively per 100 pounds (45.359 kg) of feed to be formed.

After blending in the mixing chamber 28, the hydrolyzed cellulose containing the additives is fed to a dryer 32. The dryer can be any type of dryer, such as a continuous, direct-fired rotary dryer. The mixture of hydrolyzed cellulose and food additives is fed to the dryer and is dried to a moisture content of from about 2 to about 4 percent less moisture than the desired moisture content of the finished feed product.

The dried feed material coming out of the dryer 32 is cooled and transported to a cuber or pellitizer 36. At this stage of the process the feed is a spagnum-like material. In the cuber 36 the feed is cubed or pellitized into 1-1/4 inch (3.175 cm) cubes or smaller pellets. During the cubing process, vitamin complexes, such as vitamins A, B, C, D and E complexes, can be mixed into the feed. For example, in tank 38, vitamins A and B complexes can be mixed with water and added to the feed at a rate of about 1/2 to about 1 gram per minute to the cuber to provide the proper amounts of these vitamins to the cubed feed. The water with which the vitamins are mixed reacts with the molasses already present in the feed to provide the binder which allows for the formation and stability of the cubes. Due to the drying in dryer 32 to a moisture content less than the desired end moisture content, such water added during the cubing process can raise the moisture content to the desired level.

The finished cubes are removed from the cuber, cooled and transported to storage. The vitamins are added during the cubing process to prevent possible degradation of the vitamins during the drying step in dryer 32. The temperature in dryer 32 can be sufficiently high to degrade the vitamin added and, therefore, it is desirable to add vitamins to the feed during the cubing step.

Examples 1-27

Examples 1-27 were conducted to determine the effect of hydrolysis upon bagasse obtained from sugarcane. Both acid hydrolysis and alkaline hydrolysis experiments were conducted. The effects of various concentrations of both the alkaline hydrolyzing agent and acidic hydrolyzing agent were also noted. Further, the effects of time upon the hydrolysis reaction were observed.

All of the examples, 1 through 27, were conducted in substantially the same manner. Fresh bagasse containing approximately 50 percent moisture was sieved using a 100 mesh sieve. The material not passing through the sieve was used in the experiments except that pieces larger than 1 inch (2.54 cm) wide, 2-1/2 inches (6.35 cm) long and 3/8 inch (0.9525 cm) thick were discarded. For the acid hydrolysis, 7500 milliliters (ml) each of 5 and 10 weight percent hydrochloric acid solution was prepared. For the alkaline hydrolysis, 7500 ml each of 5,

10, 20 and 30 weight percent sodium hydroxide solution were prepared. For each example, the 7500 ml hydrolyzing solution was brought to a rolling boil, the temperature recorded and maintained constant throughout the hydrolysis reaction. The boiling point and concentration of the hydrolyzing media were maintained constant by adding water to replace the water lost through vaporization. 600 grams of the sieved bagasse were gradually added to the hydrolyzing solution to prevent any sizable temperature drop. The mixture was manually stirred to insure that all of the fibers were wetted with the hydrolyzing agent. At theappropriate time period for each example, about 15 percent of the bagasse in the solution was withdrawn and washed with 10 liters of distilled water in 1000 ml increments. During the last wash with 1000 ml of water, the mixture was neutralized with the corresponding acid or alkali to a pH of 5 to 7 and the liquid was squeezed out of the sample using a jelly bag.

The wet neutralized samples of hydrolyzed cellulose were spread as uniformly as possible on a glass tray and placed in a microwave oven for a series of alternate three minutes drying and two minute cooling periods. The samples were turned over after every drying sequence until a level of approximately 5 to 10 percent moisture was obtained. Following drying, the samples were analyzed for moisture, crude fiber, ADF and NDF values, lignin, pentosans, proteins, ash content and invert sugar content.

The following Table I lists the results of hydrolysis reactions of Examples 1-27. In Table I the concentration of hydrolyzing agent is listed in the second column, headed Sample, along with the type of hydrolyzing agent used and time period for the hydrolysis reaction. The "C" stands for caustic which was an aqueous sodium hydroxide solution. The "M" stands for an acid hydrolyzing agent which was aqueous hydrochloric acid for these experiments. The time for the reaction is given in minutes as the last number of the series in the column. Thus, for example, for Example 2 a 5 percent by weight, sodium hydroxide solution was used to hydrolyze bagasse for a hydrolysis reaction sequence of 15 minutes. The temperature at which the hydrolysis reaction was conducted is given in the right hand column and was generally between 200 and 260°F (93 and 127°C).

From a review of the results listed in Table I, it is apparent that boiling the bagasse at atmospheric pressure in alkali raises the value of. the crude fiber, acid detergent fiber (ADF) and neutral detergent fiber (NDF), and at the same time, reduces the values of lignin and pentosans. TABLE I

Example Crude Invert Boiling

No. Sample Moisture Fiber ADF NDF Lignin Pentosan Protein Ash Sugar pH Temp.ºC

1 Bagasse 9.7 51.6 62.8 86.6 19.2 23.8 1.31 2.40 0.48 5.6

2 5% C-15 5.7 75.0 80.3 90.8 10.3 10.5 0.75 1.59 -0- 7.8

3 5% C-30 6.5 79.5 85.8 90.3 8.7 4.5 0.48 1.55 -0- 9.0

4 5% C-60 7.5 78.8 83.3 90.3 10.0 7.3 0.48 1.33 -0- 8.6

5 5% C-90 6.3 80.5 88.3 91.4 9.3 3.1 0.53 1.66 -0- 8.6

6 10% C-15 6.3 76.2 85.6 92.3 11.6 6.7 0.66 1.64 -0- 9.1

7 10% C-30 4.2 77.1 85.3 92.1 12.1 6.8 0.72 1.36 -0- 7.7

8 10% C-60 1.5 76.9 84.6 94.0 10.2 9.4 0.53 1.56 -0- 9.1

9 10% C-90 2.5 78.8 88.4 91.5 12.0 3.1 0.50 1.36 -0- 9.1

10 20% C-15 5.9 72.1 82.5 89.8 13.5 7.3 0.72 0.94 -0- 7.4

11 20% C-30 5.8 75.8 87.5 92.1 11.8 4.6 0.56 1.18 -0- 8.8

12 20% C-60 4.2 80.9 84.9 92.9 11.0 8.0 0.51 1.21 -0- 8.7

13 20% C-90 8.2 77.5 86.7 89.8 10.2 3.1 0.44 1.11 -0- 8.7

14 30% C-15 10.7 66.5 77.3 88.8 7.9 11.5 0.56 1.18 -0- 8.9

15 30% C-30 9.0 64.2 74.0 80.4 7.0 6.4 0.56 0.94 -0- 7.4

16 30% C-60 9.1 65.1 71.5 87.4 5.1 15.9 0.38 1.26 -0- 9.0

17 30% C-90 6.3 68.4 77.4 84.6 5.0 7.2 0.38 1.30 -0- 8.8

18 5% M-15 7.6 64.9 84.5 85.6 20.0 1.1 2.2 1166 -0- 3.7

19 5% M-30 6.0 65.1 86.8 87.4 22.7 0.6 2.0 1.64 -0- 3.6

20 5% M-60 12.0 68.3 88.1 83.4 23.5 -0- 2.1 1.48 -0- 4.3

21 5% M-90 6.2 67.1 89.7 88.4 23.2 -0- 1.6 1.53 -0- 4.3

22 10% M-15 5.3 63.5 87.4 85.6 21.5 -0- 1.8 2.03 -0- 3.8

23 10% M-30 6.9 65.5 89.2 87.1 23.3 -0- 1.0 1.92 -0- 3.9

24 10% M-60 10.0 60.3 86.8 83.4 21.2 -0- 1.5 1.75 -0- 3.8

25 10% M-90 9.9 56.8 88.0 85.9 23.5 -0- 1.1 1.79 -0- 4.2

26 20% M-15 7.5 51.5 85.1 83.1 20.1 -0- 1.3 1.83 -0- 4.1

27 20% M-30 6.8 46.3 87.9 85.1 27.0 -0- 0.9 1.74 -0- 3.9

The increase in acid detergent fiber and reduction of lignin content are an indication of increased digestibility for ruminant animals. Thus, the partial hydrolysis performed in the examples is shown to increase the ruminant's ability to assimilate the processed bagasse. The results of the examples expressed in Table I also show that the values of crude fiber, ADF and NDF, differ slightly with time and concentration up to and including a concentration of 20 percent sodium hydroxide as the hydrolyzing agent. At 30 percent sodium hydroxide concentration all the values fall off slightly with time indicating the beginning of caustic degradation of cellulose into its complex components, such as glucosides and saccharides.

The acid hydrolysis of the bagasse, when compared to alkaline hydrolysis, results in a smaller increase in crude fiber, ADF and NDF values, and a decrease in pentosans to zero while the lignin values remain almost equivalent to that of untreated bagasse. An increase of acid concentration above 10 percent results in a decrease in crude fiber, ADF and NDF values. The values of pentosans and lignin remain substantially about the same. At 20 percent concentration of acid and 30 minutes reaction time, the solution becomes black, indicating a marked degradation of the cellulose. The experiments were terminated when degradation of cellulose began.

After a reduction of about 30 percent, the values of ash remained fairly constant throughout the entire series of experiments which was as expected. The protein values increased by a factor of more than three during the acid hydrolysis. The residual sugar present in the bagasse, about one-half to one percent was substantially eliminated from the final samples. The yields of hydrolyzed bagasse on a dry basis as compared to the amount of bagasse used initially, varied with the type of hydrolyzing agent, solution concentration, bagasse particle size and hydrolysis time. In general, alkaline hydrolysis produced higher yields while acid hydrolysis produced significantly lower yields. Alkaline hydrolysis yields varied from 40 to 75 percent of the bagasse used with a 5 to 10 percent solution concentration and up to 30 minutes reaction time. Acid hydrolysis yields were 25 to 35 percent of the initial bagasse treated with a ten percent solution concentration and 30 minutes reaction time.

Example 28 Mill run bagasse was sieved through a 100 mesh screen. The particles passing through the screen were discarded. Particles greater than 1 inch (2.54 cm) wide, 2-1/2 inches (6.35 cm) long, and 3/8 inch (0.9525 cm) thick were also discarded. The remaining bagasse particles were stored in a hopper for feed to a hydrolysis reactor.

A 10 weight percent aqueous alkaline solution of sodium hydroxide in water was introduced to the hydrolysis reactor and heated to its boiling temperature. The reactor was heated by passing superheated steam at a temperature of 400°F (204°C) and pressure of 100 psi (7.031 kg/cm²) through a jacket on the outside of the reactor. The sized bagasse was added gradually to the boiling alkaline hydrolyzing solution to prevent any sizable temperature drop.

The mixture of bagasse and hydrolyzing agent was agitated by a slow speed paddle which turned at 5 to 10 revolutions per minute. The paddle provided sufficient agitation to uniformly heat and wet the bagasse to insure uniform hydrolysis. After the bagasse had been hydrolyzed for 30 minutes, the mixture was dropped from the reactor into a centrifuge, In the centrifuge the excess caustic hydrolyzing agent was separated from the hydrolyzed bagasse; The bagasse was washed with distilled water to remove remaining alkaline hydrolyzing agent. Dilute hydrochloric acid was used to wash the bagasse and to return the pH of the bagasse to a pH of 4 to 6.

The hydrolyzed bagasse can then be combined with nutritional food additives for making a ruminant animal feed.

Example 29 Ruminant Feed from.Hydrolyzed Bagasse A ruminant animal feed was prepared from hydrolyzed bagasse prepared as described in Example 28. The ruminant feed was prepared by mixing 83.2 pbw of the hydrolyzed bagasse, 3.6 parts urea, 12.0 parts molasses (dry basis), 1.2 parts calcium phosphate and 22 grams vitamin A (500,000 IU/g).

The ruminant feed thus produced is suitable for feeding to ruminant animals.

Example 30 Feed, from a 1/4 ton (226.8 kg) a day pilot plant built on the principles described in the preferred embodiment and FIG. 1, was tested for crude protein, fiber, fat and dry matter digestibility in accordance with the procedures of the Association of Official Agricultural Chemists, "Official Method of Analysis," 10th Ed., 1965. For comparison purposes, three different feeds were tested using alfalfa cube hay as the control feed. The other two feeds were formulated with the identical amounts of ingredients except that one was made with untreated bagasse and the other with bagasse prepared as described in Examples 28 and 29, except the feed contained on a 100 pound (45.359 kg) dry basis: 78.2 pounds (35.47 kg) hydrolyzed bagasse, 17.0 pounds (7.71 kg) molasses,

3.6 pounds (1.63 kg) urea, 1.2 pounds (0.54 kg) Ca₃(PO₄)₂ and 22 grams vitamin A. To this 100 pounds (45.359 kg) of feed was added 10 pounds (4.54 kg) of cottonseed meal to achieve a protein level near that for the alfalfa. Six mature crossbred wethers (sheep) weighing between 40 to 60 pounds (18.14 to 27.22 kg) each were used in each of the feed tests. Sheep were selected as the test animal as sheep are generally more selective of diets than cattle. The animals were kept in individual cages to determine all ad libitum feed intake and to enable the measurement of total amount of excrement.

The processed feed was composed of processed bagasse, cottonseed meal, urea, calcium phosphate, molasses and vitamin A. The processed bagasse rations and a similar unprocessed bagasse ration were fed to the sheep. An adjustment period of seven days or until intake was stabilized followed by a seven-day preliminary and a seven-day collection period was utilized to evaluate all feeds.

The ad libitum intake level was established during the adjustment period and approximately 90 percent of this value was fed during the subsequent preliminary and collective periods. Water was available to all animals at all times.

The sheep ate the processed bagasse ration readily during the adjustment period and throughout the trial, however, the sheep receiving the non-processed bagasse ration would not eat the ration and after three attempts they were removed from the trial. The average intake (dry matter basis) was 802 gms during the ad libitum intake period. The voluntary intake per pound of body weight was 8.02 gm/lb (8.02 gm/0.454 kg). The average dry matter consumption over the collective period was 722 gms per sheep per day for the processed bagasse feed. There was some feed refused by two sheep, although this was only a small amount - less than 80 gms for each sheep over the period. This refused feed was analyzed chemically and subtracted from the amount of feed offered for the digestive trial. The relative intake of this feed, as compared to textbook information on alfalfa hay, was 57. The nutritive value index was 56.

The ration analysis is presented in Table II, and the digestive coefficients are given in Table III. The total digestible nutrient (TDN) values are. also presented in Table III. In many respects, the processed bagasse is a more useful feed than the tabular data for alfalfa hay. Digestion coefficients were higher for the processed bagasse for fiber (74.2 v. 46.1); either extract (88.8 v. 38.1); and nitrogen-free extract (80 v. 69.9). The tabular data for alfalfa hay is higher for crude protein (74.5 v. 61.2). The TDN value for alfalfa hay was 54.8 and for the processed bagasse was 70.97. The theoretical values of digestion coefficients as given in the "National Research Council Publication," 1684, are also listed in Table III. The results of the feeding tests show that the sheep accepted the feed made from bagasse and were able to sustain themselves on it. In comparing the sheep that ate the bagasse-based feed with the sheep that ate the alfalfa feed, the sheep that were fed the bagasse-based feed fared as well as those fed alfalfa. Further, no undesirable side effects were exhibited by the sheep fed the bagasse-based feed. TABLE II

Ration Analyses (mixed feed)

Chemical Analyses Alfalfa Ration Feedback CUBE HAY

Dry matter, %* 91.01 94.6

Acid detergent fiber, %* 39.4 62.1 71.6

Crude protein, %* 17.9 12.9 6.8

Ash, %* 9.8 5.5 3.4

Ether extract, %* 1.7 1.1 0.5

Nitrogen-free extract, %* 31.3 18.4 17.8

Lignin, % 12.1 9.5 12.8

Cellulose, % 25.5 51.8 58.1

Gross energy, kcal/gm 4.37 4.180 4.265

Neutral detergent fiber, % 49.1 70.9 85.8 Mineral Analyses

Phosphorus, % .22 0.32 0.14

Calcium, % 1.26 0.27 0.15

Potassium, % 1.63 0.74 0.37

Magnesium, % .48 0.21 0.13

Copper, ppm 8 81 63

Zinc, ppm 19 288 259

* Used in computing total digestible nutrients (TDN).

TABLE III

Ration Digestibility Comparison

Digestion Coefficient

Bagasse Alfalfa Text¬

Item Feed Cubes book

Organic Matter 73.7 59.7 --

Acid Detergent Fiber 74.2 46.1 45

Crude Protein 61.2 74.5 71

Ether Extract 88.8 38.1 30

Nitrogen-Free Extract 80.0 69.9 70

Gross Energy, kcal/gm 68.8 56.9 --

Total Digestible Nutrients (TDN) 70.97 54.8 52

Example 31

A ruminant feed prepared from hydrolyzed bagasse as described in Examples 28 and 30 was tested as a feed for dairy cattle. A test herd of 24 holstein dairy cows, in the early stages of lactation, was selected at random from 300 cows and put on control rations for 56 days prior to the actual test period to determine their ad libitum feed consumption.

The herd was divided in half. One-half was fed alfalfa cube hay and the other half was fed the processed bagasse feed for 56 days in accordance with the schedule in Table IV which amounted to 90 percent of their ad libitum intake.

Each cow was identified for the records by an ear tag. Each test group of 12 cows was kept in a separate corral and milked as a group.

The 20 percent grain mix for each cow in both groups was fed in the following manner:

10.5 lbs. (4.76 kg) in the milk parlor in the morning;

10.5 lbs. (4.76 kg) in the milk parlor in the evening;

5.0 lbs. (2.27 kg) of a 12 percent grain mix during the day outside; and

4.0 lbs. (1.81 kg) of the same ration outside at night.

Milking was done in a double three-unit Herringbone milk parlor with automatic feeding and milking machines.

The roughage rations of alfalfa cube hay and the processed bagasse feed were fed free choice in this manner:

10.0 lbs. (4.54 kg) per cow in the morning; and

10.0 lbs. (4.54 kg) per cow at night.

Water and a dairy mineral mix were constantly available to all cows.

To measure the performance of each group, the milk production from each cow was weighed weekly on Wednesday. On the same day composite milk samples were taken from each cow and analyzed for its butterfat and solids, nonfat content. The results of this testing are indicated in Tables IV, V, VI and VII, and are shown in FIGS. 2, 3 and 4.

In summary, the results of the tests on the hydrolyzed, bagasse-based dairy feed appear very positive. The results indicate that the animals accept the feed, that the butterfat content increases and the production does not significantly differ when the animals are fed the hydrolyzed, bagasse-based animal feed instead of the normal alfalfa ration. Fecal matter from both groups appeared to be the same. None of the animals exhibited any undesirable side effects. Statistically speaking, the animals did as well on the hydrolyzed bagasse feed as on alfalfa.

The following examples illustrate formulations of an animal feed using a natural protein containing material.

Example 32 A ruminant animal feed using only taro leaves and stems which have been harvested together like alfalfa, is prepared dry with a moisture content of 5 percent.

The feed has the following composition based on a 100 pound (45.36 kg) dry basis.

Weight Percent Percent Percent

Item Lbs. Kg. Protein Calcium Phosphorus

Taro Stems 44 19.96 3.25 0.22 1.14

Taro Leaves 44 19.96 12.75 0.66 0.15

Molasses 12 5.44 .50 .09 .01

Total 100 45.36 16.50 .97 1.30

Additives, like urea, calcium carbonate, vitamin A, etc., can be added to bring this feed up to a desired National Research Requirements Specification to allow its use as a one-feed balanced ration. Example 33 A ruminant animal feed is prepared using partially hydrolyzed bagasse which was prepared as described in Example 28.

The feed has the following composition on a 110 pound dry basis:

Weight Percent Percent Percent

Item Lbs. Kg Protein Calcium Phosphorus

Hydrolyzed Bagasse 35.0 15.88 4.38 0.07 0.07

Taro (Leaves only) 63.7 28.89 19.11 0.95 .22

Molasses 10.0 4.54 .42 .08 .01

Calcium Phosphate 1.3 0.59 -- .52 .39

Vitamin A (10 gms) -- -- -- -- --

Total 110.0 49.90 23.91 1.62 0.69

Example 34

A ruminant animal feed is prepared using partially hydrolyzed bagasse which has been prepared as described in Example 29.

The feed has the following composition on a 100 pound basis:

Weight Percent Percent Percent

Item Lbs. Kg Protein Calcium Phosphorus

Bagasse Feed 57.1 25.9 7.13 .18 .18

Taro (leaves only) 42.9 19.46 12.52 0.64 .15

Total 100.0 45.36 19.63 0.82 .33

The processes herein and the ruminant feeds made from such processes provide a new, useful and efficient feed product using basic materials which are generally considered waste products and which have little nutritive or beneficial use as foodstuffs for humans. The ruminant animal feeds produced by these processes are readily consumed by ruminants and have been shown to be substantially equivalent to an alfalfa feed for such ruminants. Generally,, alfalfa feed is considered to be an efficient and beneficial food source for ruminant animals. The use as a feed material of cellulose material, which is generally not used, frees material that is generally utilized as feed for animals and makes it available for use and consumption by humans.

Claims

WHAT IS CLAIMED IS:

1. A process for making ruminant feeds from cellulose material comprising the steps of: a. shredding said cellulose material to a size of less than about 1 inch (2.54 cm) wide, 2-1/2 inches (6.35 cm) long and 3/8 inch (0.9525 cm) thick; b. hydrolyzing the shredded cellulose material in a hydrolyzing medium under hydrolyzing conditions sufficient for maintaining a fiber length of the cellulose material at least about 3/8 (0.9525 cm) of an inch; c. separating the hydrolyzed cellulose material from the hydrolyzing medium; d. washing the hydrolyzed cellulose material with at least one aqueous wash for removing remaining hydrolyzing medium; e. neutralizing the hydrolyzed cellulose material for adjusting the pH to about 4 to 6; f. mixing feed additives selected from the group consisting of natural protein-containing material, urea, minerals, filter mud from sugar mills, molasses, water, vitamins and mixtures thereof with the hydrolyzed cellulose material; g. drying the mixture of hydrolyzed cellulose material and feed additives to a moisture content from about 2 to about 4 percent lower than the desired moisture content of the finished ruminant feed; and h. pelletizing the mixture of hydrolyzed cellulose material and feed additives for forming a ruminant feed.

2. A process as recited in claim 1 wherein the hydrolyzing medium is an alkaline hydrolyzing medium.

3. A process as recited in claim 2 wherein the alkaline hydrolyzing medium is an aqueous sodium hydroxide solution that is up to about 20 percent by weight sodium hydroxide.

4. A process as recited in claim 2 wherein the alkaline hydrolyzing medium is an aqueous ammonium hydroxide solution that is up to about 20 percent by weight ammonium hydroxide.

5. A process as recited in claims 3 or 4 wherein the mixture of the shredded cellulose material and aqueous alkaline solution is heated to its boiling temperature of about 200° to about 280°F (93 - 138°C) for up to about 30 minutes with slow agitation of the mixture for maintaining cellulose fiber length of at least about 3/8 inch (0.9525 cm).

6. A process as recited in claim 5 wherein the mixture is agitated with a mechanical stirrer rotated at about 5 to 10 revolutions per minute.

7. A process as recited in claim 5 wherein the mixture is agitated by introducing air into the mixture at about 3 to 4 scfm (0.084951 to 0.113268 cubic meters per minute) per 10 cubic feet (0.28317 cubic meters) of reactor volume.

8. A process as recited in claim 1 wherein the hydrolyzing step is conducted by the steps comprising heating the cellulose material and hydrolyzing medium to the boiling temperature from about 200° to about 280°F (93 - 138°C) for up to 90 minutes with agitation provided for maintaining cellulose fiber length of at least about 3/8 inch (0.9525 cm) and complete hydrolysis.

9. A process as recited in claim 8 wherein the hydrolyzing medium is an aqueous acidic solution.

10. A process as recited in claim 9 wherein the hydrolyzing medium is up to about 20 percent by weight aqueous HCl solution.

11. A process as recited in claim 8 wherein the hydrolyzing medium is an aqueous alkaline solution.

12. A process as recited in claim 1 wherein the feed additive mixed with the hydrolyzed cellulose material is a natural protein-containing material selected from the group consisting of cottonseed meal, soybean meal, taro, manioc, cassava, tapioca and mixtures thereof.

13. A process as recited in claim 1 wherein the hydrolysis step is conducted for a time sufficient to reduce the lignin content of the cellulose material to about 7 to 10 percent by weight and an acid detergent fiber to lignin ratio of at least 4 to 1.

14. A process as recited in claim 1 wherein the natural protein-containing material comprises a plant selected from the group consisting of taro, manioc, cassava, tapioca and mixtures thereof, which has been conditioned by shredding, chopping, washing and drying at a temperature up to the charring temperature of the plant.

15. A process as recited in claim 1 wherein the natural protein-containing material comprises a plant selected from the group consisting of taro, manioc, cassava, tapioca and mixtures thereof, which has been conditioned by shredding, chopping, washing, and boiling in water for up to about 10 minutes and dried to a moisture content of less than about 10 weight percent.

16. A process for making ruminant feeds from cellulose material comprising the steps of: a. shredding said cellulose material to a size of less than about 1 inch (2.54 cm) wide, 2-1/2 inches (6.35 cm) long and 3/8 inch (0.9525 cm) thick; b. hydrolyzing the shredded cellulose material in a hydrolyzing medium under hydrolyzing conditions sufficient for maintaining a fiber length of the cellulose material at least about 3/8 (0.9525 cm) of an inch; c. maintaining a constant hydrolyzing temperature by adding water; d. maintaining a constant hydrolyzing pH by adding additional hydrolyzing medium solution; e. separating the hydrolyzed cellulose material from the hydrolyzing medium; (Claim 16 cont.)

f. washing the hydrolyzed cellulose material with at least one aqueous wash for removing remaining hydrolyzing medium, and reconstituting it by evaporation for reuse; g. neutralizing the hydrolyzed cellulose material for adjusting the pH to about 4 to 6; h. mixing feed additives selected from the group consisting of natural protein-containing material, urea, minerals, filter mud from sugar mills, molasses, water, vitamins and mixtures thereof with the hydrolyzed cellulose material; i. drying the mixture of hydrolyzed cellulose material and feed additives to a moisture content from about 2 to about 4 percent lower than the desired moisture content of the finished ruminant feed; and j. pelletizing the mixture of hydrolyzed cellulose material and feed additives for forming a ruminant feed.

17. A process as recited in claim 16 wherein the hydrolyzing medium is an alkaline hydrolyzing medium.

18. A process as recited in claim 17 wherein the mixture of the shredded cellulose material and aqueous alkaline solution is heated to its boiling temperature of about 200° to about 280°F (93 - 138°C) for up to about 30 minutes with slow agitation of the mixture for maintaining cellulose fiber length of at least about 3/8 inch (0.9525 cm).

19. A process as recited in claim 18 wherein the mixture is agitated with a mechanical stirrer rotated at about 5 to 10 revolutions per minute.

20. A process as recited in claim 18 wherein the mixture is agitated by introducing air into the mixture at about 3 to 4 scfm (0.084951 to 0.113268 cubic meters per minute) per 10 cubic feet (0.28317 cubic meters) of reactor volume.

21. A ruminant animal feed comprising partially hydrolyzed cellulose material prepared by the process comprising the steps of: a. shredding a cellulose material to a size of less than about 1 inch (2.54 cm) wide; 2-1/2 inches (6.35 cm) long and 3/8 inch (0.9525 cm) thick; b. hydrolyzing the shredded cellulose material in a hydrolyzing medium under hydrolyzing conditions sufficient for maintaining a fiber length of the cellulose material at least about 3/8 (0.9525 cm) of an inch; c. separating the hydrolyzed cellulose material from the hydrolyzing medium; d. washing the hydrolyzed cellulose material with at least one aqueous wash for removing remaining hydrolyzing medium; e. neutralizing the hydrolyzed cellulose material for adjusting the pH to about 4 to 6; f. mixing feed additives selected from the group consisting of natural protein-containing material, urea, minerals, filter mud from sugar mills, molasses, water and mixtures thereof, with the hydrolyzed cellulose material; (Claim 21 cont. )

g. drying the mixture of hydrolyzed cellulose material and feed additives to a moisture content from about 2 to about 4 percent lower than the desired moisture content of the finished ruminant feed; and h. pelletizing the mixture of hydrolyzed cellulose material and feed additives for forming a ruminant feed.

22. A ruminant animal feed as recited in claim 21 wherein the hydrolyzing medium is an alkaline hydrolyzing medium.

23. A ruminant animal feed as recited in claim 22 wherein the alkaline hydrolyzing medium is an aqueous sodium hydroxide solution that is up to about 20 percent by weight sodium hydroxide.

24. A process as recited in claim 22 wherein the alkaline hydrolyzing medium is an aqueous ammonium hydroxide solution up to about 20 percent by weight ammonium hydroxide.

25. A ruminant animal feed as recited in claim 23 or 24 wherein the mixture of the shredded cellulose material and aqueous alkaline solution is heated to its boiling temperature of about 200° to about 280°F (93 - 138°C) for up to about 30 minutes with slow agitation of the mixture for maintaining cellulose fiber length of at least about 3/8 inch (0.9525 cm).

26. A ruminant animal feed as recited in claim 25 wherein the mixture is agitated with a mechanical stirrer rotated at about 5 to 10 revolutions per minute.

27. A ruminant animal feed as recited in claim 25 wherein the mixture is agitated by introducing air into the mixture at about 3 to 4 scfm (0.084951 to 0.113268 cubic meters per minute).

28. A ruminant animal feed as recited in claim 21 wherein the hydrolyzing step is conducted by the steps comprising heating the cellulose material and hydrolyzing medium to the boiling temperature from about 200° to about 280°F (93 - 138°C) for up to 90 minutes with agitation provided for maintaining cellulose fiber length of at least about 3/8 inch (0.9525 cm) and complete hydrolysis.

29. A ruminant animal feed as recited in claim 28 wherein the hydrolyzing medium is an aqueous acidic solution.

30. A ruminant animal feed as recited in claim 29 wherein the hydrolyzing medium is a 5 to 20 percent by weight aqueous HCl solution.

31. A ruminant animal feed as recited in claim 28 wherein the hydrolyzing medium is an aqueous alkaline solution.

32. A ruminant animal feed as recited in claim 21 wherein the hydrolysis step is conducted for a time sufficient to reduce the lignin content of the cellulose material to about 7 to 10 percent by weight and an acid detergent fiber to lignin ratio of at least 4 to 1.

33. A ruminant animal feed as recited in claim 21 wherein the feed additives comprise up to about 75 weight percent of the feed.

34. A ruminant animal feed as recited in claim 32 wherein the natural protein-containing material is selected from the group consisting of cottonseed meal, soybean meal, taro, manioc, cassava, tapioca and mixtures thereof.

35. A ruminant animal feed as recited in claim 34 further comprising vitamin supplements.

36. A ruminant animal feed as recited in claim 21 wherein the natural protein-containing material comprises a plant selected from the group consisting of taro, manioc, cassava, tapioca and mixtures thereof, which has been conditioned by shredding, chopping, washing and drying at a temperature up to the charring temperature of the plant.

37. A ruminant animal feed as recited in claim 21 wherein the natural protein-containing material comprises a plant selected from the group consisting of taro, manioc, cassava, tapioca and mixtures thereof, which has been conditioned by shredding, chopping, and washing and boiling in water for up to about 10 minutes and dried to a moisture content of less than about 10 weight percent.

38. A ruminant animal feed as recited in claim 21 comprising at least 50 pbw hydrolyzed cellulose material, up to about 10 weight percent urea, up to about 2.5 weight percent calcium phosphate and up to about 30 weight percent molasses.

39. A ruminant animal feed comprising partially hydrolyzed cellulose material prepared by the process comprising the steps of: a. shredding a cellulose material to a size of less than about 1 inch (2.54 cm) wide, 2-1/2 inches (6.35 cm) long and 3/8 inch (0.9525 cm) thick; b. hydrolyzing the shredded cellulose material in a hydrolyzing medium under hydrolyzing conditions sufficient for maintaining a fiber length of the cellulose material at least about 3/8 (0.9525 cm) of an inch; c. maintaining a constant hydrolyzing temperature by adding water; d. maintaining a constant hydrolyzing pH by adding additional hydrolyzing medium solution; e. separating the hydrolyzed cellulose material from the hydrolyzing medium; f . washing the hydrolyzed cellulose material with at least one aqueous wash for removing remaining hydrolyzing medium; g. neutralizing the hydrolyzed cellulose material for adjusting the pH to about 4 to 6; h. mixing feed additives selected from the group consisting of natural protein-containing material, urea, minerals, filter mud from sugar mills, molasses, water and mixtures thereof, with the hydrolyzed cellulose material; (Claim 39 cont. )

i. drying the mixture of hydrolyzed cellulose material and feed additives to a moisture content from about 2 to about 4 percent lower than the desired moisture content of the finished ruminant feed; and j. pelletizing the mixture of hydrolyzed cellulose material and feed additives for forming a ruminant feed.

40. A ruminant animal feed as recited in claim 39 wherein the alkaline hydrolyzing medium is an aqueous sodium hydroxide solution that is up to about 20 percent by weight sodium hydroxide.

41. A ruminant animal feed as recited in claim 40 wherein the mixture of the shredded cellulose material and aqueous alkaline solution is heated to its boiling temperature of about 200° to about 280°F (93 - 138°C) for up to about 30 minutes with slow agitation of the mixture for maintaining cellulose fiber length of at least about 3/8 inch (0.9525 cm).

42. A ruminant animal feed as recited in claim 39 wherein the mixture is agitated with a mechanical stirrer rotated at about 5 to 10 revolutions per minute.

43. A ruminant animal feed as recited in claim 39 wherein the mixture is agitated by introducing air into the mixture at about 3 to 4 scfm (0.084951 to 0.113268 cubic meters per minute).

44. A ruminant animal feed as recited in claim 39 wherein the hydrolyzing step is conducted by the steps comprising heating the cellulose material and hydrolyzing medium to the boiling temperature from about 200° to about 280°F (93 - 138°C) for up to 90 minutes with agitation provided for maintaining cellulose fiber length of at least about 3/8 inch (0.9525 cm) and complete hydrolysis.

45. A ruminant animal feed as recited in claim 39 wherein the hydrolysis step is conducted for a time sufficient to reduce the lignin content of the cellulose material to about 7 to 10 percent by weight and an acid detergent fiber to lignin ratio of at least 4 to 1.

46. A ruminant animal feed as recited in claim 39 wherein the natural protein-containing material is selected from the group consisting of cottonseed meal, soybean meal, taro, manioc, cassava, tapioca and mixtures thereof.

47. A process as claimed in claim 1 or 16 wherein the feed additives are mixed with the hydrolyzed cellulose by blending the feed additives in water and spraying the resulting aqueous solution into the hydrolyzed cellulose.