US2940858A - Method of making fodder from chopped straw - Google Patents

Description

United States Patent METHOD OF MAKING FODDER FROM CHOPPED STRAW Alfred Flechsig, Zwonitz, Germany, assignor of one-half to Paul O. Tobeler, doing business as Trans-Oceanic, Los Angeles, Calif.

No Drawing. Filed Oct. 31, 1957, Ser. No. 693,507

1 Claim. (Cl. 99-9) The present invention relates to new and improved process for manufacturing fodder or edible foodstuff from straw.

In order to completely understand the invention, it is necessary to understand something of the nature of straw. It is well known that straw is substantially undigestible as it is obtained from various agricultural processes. The reason for this lies primarily in the fact that straw itself is composed of a plurality of individual cells, each of these cells containing interior nutrient material surrounded by a cell wall. Such cell walls are composed of a complex mixture of various chemical ingredients, such as, for example, lignins and pantosans and cellulose products bound together by these lignins and pantosans. Those skilled in the art to which this invention pertains will realize that the term lignin is employed as a generic term to desigmate a large number of cellulose-like substances, such as lignose, lignone and the like. Those skilled in the art to which this invention pertains will further realize that the term pantosans relates to a group of gum-like or resinlike materials which are frequently referred to as hemior presdo-celluloses. In order to get at the nutrient material within a cell structure in straw, it is necessary to weaken and to destroy as by various degradation reactions the cell wall structures encountered.

A number of prior processes have been developed for this purpose. The prior processes upon which this invention can be said to be based involved the digestion of straw with an alkaline material such as, for example, caustic soda or the like in water. Such alkaline solutions will tend upon heating to break down the cell walls in straw. These prior processes tend to result in relatively tasteless products which are deficient in vitamin content and the like. In order to remedy thisdeficiency, it has been proposed in the past to add to the product of such alkaline digestion of straw various nutrient materials such as molasses, such nutrients serving in some cases to neutralize the caustic employed during digestion. I

Caustic digestion processes of the category briefly indicated in the preceding paragraph are considered relatively unpredictable because of a large number of factors. One of these is the variation in the cell wall structure in different types of straws and even in straws obtained from different sources. Because of such variations and other factors, the reactions accompanying the treatment of straw in a caustic bath are difiicult to control accurately so as to obtain precisely the desired products. In many cases the digestion treatment employed with this prior type of process results in the nutrient compounds in the straw being degraded to water soluble materials. Such water soluble materials may, in many cases, be lost.

An object of the present invention is to provide a new and improved process for manufacturing fodder from straw. It will be realized that the term fodder utilized herein is of a generic category. Thus, if desired, the word foodstufi may be substituted for this term throughout this specification. The process of the present invention is designed so as to produce a product which has a high nutrient content and which has an acceptable taste so that it is readily accepted by cattle for "feeding pur- .poses. Because of the nature of this invention, it is not may be stated in essentially summary form that it involves the modification of an existing process for producing fodder from straw by the addition of yeast to a bath containing straw, water and an alkaline inorganic compound after such a mixture has been heated to a sufiicient extent so as to partially cause degradation of the lignin and pentosan structures within the cell walls of the straw and heating the mixture containing this yeast until plasmolysis of the yeast is obtained. Such yeast serves a number of purposes as will be hereinafter described in more detail. The process also involves a further step of neutralizing the final mixture obtained after heatingyeast in the presence of straw, water and an alkaline-inorganic compound, and the removal of water from the, neutralized mixture so as to obtain a product which be satisfactorily transported and may be easily fed to cattle. It may also be stated in essentially summary form that the invention concerns a product produced by v lated materials having a similar cell structure. In order to promote as complete a reaction as possible in the proc-. ess of this invention, it is preferred to chop the raw material utilized into finely divided particles by established techniques. In general, the more complete the division of the initial material, the more complete and uniform the reactions obtained :during subsequent operations of the process.

The first of these subsequent operations involves mixing chopped straw with water and inorganic caustic compound. Suficient water is preferably utilized so as to completely cover the reaction mixture. The amount of caustic employed may be varied within wide limits depending upon the speed of the reaction desired, the specific aqueous caustic bath employed, and the temperature to be used for digestion. In general, the reactions ob tained and the time required will be promoted or shortened respectively by employing either large quantities of caustic and/or comparatively strong caustics. Those. skilled in the art to which this invention pertains will be able to readily determine by routine experimentation what caustics and what concentrations of these caustics can be most satisfactorily employed for any particular type of straw. It may be stated, however, that such organic caustics as sodium hydroxide, calcium hydroxide and the like may be employed. a .r

After a mixture is formed of chopped straw, water and caustic as indicated above, this mixture-istreated at an elevated temperature until the lignins and pentosans in: the cell wall structure of the straw being treated is-a t tacked or broken down to a substantial extent. This initial digestion is preferably not carried to thepoint th at' the cell wall structure of the straw is completely degradeg:l. Because of the chemical complexity of-the reactions oc'-- curring, it is considered impossible to specify in 'more' detail the time required for this step. This step is, however, inter-related with heating the reaction mixture in the presence of yeast as will be explained so that both Patented June 14, 1960 of these steps result in substantially completely breaking down the cell wall structure. In general, the more elevated the temperature employed by this initial treatment, the more rapid the results obtained. It is preferred to least 18Ufiypreferably the temperature of steam at 'atmosphericmressure' (approximately 212 F.) is utilized.

Following-the'first digestion step indicated above, yeast Those skilled in the art will realizethat all 2,940,858 H A v ellipsoide us, S. piriformis, S. pombe and S. mellacei can be utilized. Certain of these yeasts normally are found in conjunctionwith various bacteria, and such bacteria arefof course, normally liilledby the digestion process carried out with the yeast as part of the reaction mixture. It is normally preferred to utilize with this invention in 'what'iscommonly termed beer yeast inasmuch as this particular composition is readily available, is cheap and has-1a hig'h nutrient alue. The quantity of yeast utilized with the invention maybe varied within wide limits. it

7 ispreferred to use sufiicient yeast 'so that the yeast will result in a desired product having "a desirednutrient con-- tent-for any particulargfinaluse as a foodstuff. Also, suflicient yeast should be added in sufiicient amount so that this yeast appears to' affect the reactions obtained during the treatment of the reaction mixture containing 7 yeastso as to prevent the formation of unwanted degradaproducts of'nutrient material within thestraw employed.

' 'Thetemperature of the second digestion step, which in actuality is really a continuation of the initial digestion, is preferably the same as that employed for the initial digestion of'a mixture containing only straw, caustic and waten' If desired make up wa'ter'and additional caustic may be added during the "addition of the yeast so as to promote 'or'speedup the reactions obtained.

During the digestion or cooking in the presence or yeast,'the yeast, itself undergoes plasmolysis as thevariou's' V li gnin s and pentosans within the cell wall structures of the initial straw are degraded so as to expose nutrients in the straw-t0 the reaction mixture. Apparently the yeast serves during this stage of the :process to prevent the formation of unwanted degradation products from the nutrient materials within the cell walls of the initial straw. The plasmolysis of the yeast apparently tends to result in the formationof intermediate products within the reaction vessel employed which tend to neutra'liz'e the causticutilized for thedigestion, and, hence, to effect the speed 'ori-ate ofattaek of the nutrient material within the straw byithe caustic employed. It is specificallyjto be noted that during the'p'lasm'olysis of yeast during the One preferred method of doing this is by heating the product obtained at a temperature slightly over the boiling point of water, such as a temperature offrom 212 F. to 250 F. This heating, if carried out in extremely elevated temperatures will, of course, result in undesired reactions impairing the'valu'e of the product obtained. Also if an extremely elevated temperature is employed in heating, some of the fvolatile compounds' having a nutrient value will apparently tend to be driven off of the product obtained; If-desired, thejproduet may be dehydrated completely so that it maybe sold in'sacks,

etc. -In 10111.51 '59 r'complete this specificationthe following specific example of the process of. this invention is set forth. It is to beund'erstood thatfthi's specific example is given by way of illustration only and is not to be taken as limiting the invention in any respect. Obviously the procedure set *forth in this example may beralte'red within comparatively wide limits without depar'ting" from the essential features of this invention.

I V "Erample I 7 One hundred pounds of -finely divided or chopped straw was placed inwoo'den tank containing steam tubes in approximately three equal ilaye'rs; 1.6 lbs. of sodium hydroxide were positioned between each of the three layers of thejstraw, The tank was then heated for a periodof one hour at 212 F. through the useo'f steam supplied through the tubing. At the end of this period lbs. of water was added and the mixture was boiled for another hour. Afterthis, the entire reaction mixture was cooled. After it"had reached a temperature cat-40 C. a lime-yeast mixture containing '10 lbs. of quick lime, 25 lbs. of water and 3 lbs. of dry beer ye'ast'was added to the entire reaction mixture and the resulting "mixture was stirred. An additional 25 "lbs. of water was then added. The entire. mixture created as aresult of these operations was then "cooked'through the'u'se of'steam at 212"F. for a period of two hours. After thi's'was'done, the reaction solution or mixture was neutralized with hydrochloric acid to a pH of about 7. In general,

v about one cubic centimeter of concentrated hydrochloric second digestion step, the vitamin and other nutrient V oontentof .the yeast employed is apparently not affected,

' these nutrients remain in the final product obtained so asto be available for use in feeding. The limiting time: as to the second digestion step is considered to be the time required so as to effect substantially complete plasmolysis of the yeast without effecting a breakdown of l-the'ch'emical compounds within the yeast which are. valuable for feed purposes.

ides with the time required to prevent unwanted .degra- This. time apparently .coindation of the nutrient materials within straw.

Following these operations the reaction mixture obt'ained may be readily. neutralized in accordance with established techniques of any common mineral acid such for example, hydrochloric acid; preferably the neutralization is carried out so as to achieve. a pH of from about 6 to about 8, since cattle apparently -do not object to "foodstuff'having a pH within this range. In order to make this product acceptable for use as a foodstutf and in order to make'it inexpensive -to transport, it is normalacid is required per kilogram of reaction solution in order to aifect neutralization. The so neutra'lized mixture was then dried to a moisture content of about 20%- 23'% by heating it at a temperature of from about 2 12 to "250" F.

I claim: 7

A process for "manufacturing fodder chopped straw which comprises: heating a mixture of chopped straw, water and soditim hydroxide at a temperature of 212 F. for "a period of'two hours so as to partially break down the cell wall structure within said straw,

' adding beer yeast, water and quick "lime to "the so-he'ated mixture; heating theresulting mixture 'atfa temperature of 212 F. for a period of'two hours'so ast'o plasmolyze said yeast and ISO 3810 break down the saidcell wall structure-within straw; neutralizing the'reaction "mixture containing said yeast with'hydroc'hloric acid to a pH of from about '6 to 8; and removing. water fromsaid neutralized mixture. Y

References Cited in the tile of this patent UNITED STATES PATENTS:

7 854,791 Ahlers -May 1-3,. 1907' 1,442,322 -Beckman Jan. 16-1923 7 FOREIGN PATENTS a 21,708 Great Britain 1912 OTHER REFERENCES 7 JukelsrA-merican BrewenJune .1941, .pp. 40-43.