Abstract:
This invention is a method for making protein blocks for livestock feeding by mixing together distillers solubles, molasses, and tallow, wherein the distillers solubles constitute the primary ingredient in the protein block and the molasses are only a minor constituent of said protein block; removing water from the mixture of distillers solubles, molasses, and tallow using heat and vacuum, so as to condense the mixture; combining the condensed mixture of distillers solubles, molasses, and tallow with premixtures of vitamins, minerals, and other nutrients; pouring the combination of condensed distillers solubles, molasses, and tallow plus nutrient premixtures into molds while the combination is still hot; and cooling the combination to form a protein block.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application claims the benefit of U.S. provisional application No. 60/486,494 filed Jul. 10, 2003. 
     
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
       [0002]     Not Applicable.  
       APPENDIX  
       [0003]     Not Applicable.  
       BACKGROUND OF THE INVENTION  
       [0004]     1. Field of the Invention  
         [0005]     This invention relates generally to the manufacture of protein feed blocks for livestock and, more particularly, to the use of corn distillers solubles as the primary constituent in this process.  
         [0006]     2. Related Art  
         [0007]     Distillers solubles and grains are constituents of the stillage that is a by-product of ethanol production. These stillage by-products contain many nutrients including high protein levels. While the grain portion of the stillage has been extensively utilized as an animal feed product, the demand for solubles has been limited and thus the price paid to distilleries has been low. Furthermore, the demand for distillers solubles that are the by-products of dry-grind ethanol production has been much lower than the corresponding by-products of wet mill ethanol production. To increase the usefulness, demand, and thus the price paid for dry-grind distillers solubles, herein are described protein blocks for livestock feeding which incorporate distillers solubles as the primary constituent as well as the methods for making such protein blocks.  
         [0008]     U.S. Pat. No. 6,440,478 B1 to Benton et al. teaches a method of making feed blocks involving heating and evaporation of water from a syrup mixture while under vacuum; the problem of feed blocks absorbing moisture in high humidity environments; the need for physical stability of the feed blocks; the degradation of sugars, vitamins, and other nutrients by heat during processing of the feed block materials; the addition of lipid (lecithin) to the feed block mixture; the control of temperature as a variable in feed block formation, including the effect of temperature on the Maillard reaction; the forming of heated and condensed syrup mixtures into feed blocks for livestock; and the cooling of the formed blocks to produce the final product.  
         [0009]     U.S. Pat. 5,260,089 to Thomberg teaches a method of making feed blocks which are substantially free of molasses; and of making feed blocks containing distillers grains and solubles wherein nutritional supplements make up less than half of the total weight of the block.  
         [0010]     U.S. Pat. No. 4,631,192 to Mommer et al. teaches both continuous flow and batch mixing processes for making feed blocks; pouring of heated material into containers for forming into feed blocks; and addition of vitamins and other nutrients as minor constituents of the feed block material.  
         [0011]     U.S. Pat. No. 4,349,578 to Wright et al. teaches the difficulties of using molasses as a feed block binding material; the use of high percentages of dried steep liquor concentrate from wet mill ethanol production in making animal feed blocks; and the need for feed blocks to withstand field conditions without weathering and cracking.  
         [0012]     U.S. Pat. No. 3,961,081 to McKenzie teaches a batch mixing method for making feed blocks; heating of the feed material in the presence of reduced vacuum to remove excess water; and the pouring of heated material into molds with subsequent cooling and hardening into feed blocks.  
         [0013]     U.S. Pat. No. 4,089,701 to Shimizu et al. teaches a batch mixing process for making feed blocks; addition of fats, oils, and esters of fatty acids to feed block mixtures; and the heating of the feed material under reduced pressure to remove water and concentrate the mixture.  
         [0014]     U.S. Pat. No. 4,234,608 to Linehan teaches the addition of tallow to animal feed blocks containing molasses, vitamins, and other nutrients.  
         [0015]     U.S. Pat. No. 5,789,001 to Klopfenstein et al. teaches the addition of lipids to feed blocks; and the effects of pH, temperature, moisture, and time on the progression of the Maillard reaction in the manufacture of feed blocks.  
         [0016]     U.S. Pat. No. 3,952,115 to Damico et al. teaches the use of additives to control Strecker degradation and the Maillard reaction in the processing of cereal grains into animal feed products.  
       SUMMARY OF THE INVENTION  
       [0017]     An aspect of the present invention is to provide a method for using distillers solubles as the primary constituent in making protein blocks for livestock feeding.  
         [0018]     In accordance with the above aspect of the invention, there is provided a method for making protein blocks for livestock feeding by mixing together distillers solubles, molasses, and tallow, wherein the distillers solubles constitute the primary ingredient in the protein block and the molasses is only a minor constituent of said protein block; removing water from the mixture of distillers solubles, molasses, and tallow using heat and vacuum, so as to condense the mixture; combining the condensed mixture of distillers solubles, molasses, and tallow with premixtures of vitamins, minerals, and other nutrients; pouring the combination of condensed distillers solubles, molasses, and tallow plus nutrient premixtures into molds while the combination is still hot; and cooling the combination to form a protein block.  
         [0019]     These aspects are merely illustrative of the innumerable aspects associated with the present invention and should not be deemed as limiting in any manner. These and other aspects, features and advantages of the present invention will become apparent from the following detailed description when taken in conjunction with the referenced drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0020]     The accompanying drawings, which are incorporated in and form a part of the specification, illustrate the embodiments of the present invention and together with the description, serve to explain the principles of the invention. In the drawings:  
         [0021]      FIG. 1  schematically illustrates the production of various stillage by-products following the fermentation of grains to make ethanol.  
         [0022]      FIG. 2  schematically illustrates the production of protein blocks.  
         [0023]      FIG. 3  illustrates the steam jacketed kettle used to heat the mixture under reduced pressure. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0024]     Referring to the accompanying drawings in which like reference numbers indicate like elements,  FIG. 1  illustrates the steps that are taken in the process in which fermenters  10  ferment grains to the subsequent distillation  12  of ethanol to the production of various by-products from the whole stillage that remains after distillation. By the use of centrifuges or screens  14 , wet grains are separated from liquid solubles. The liquid solubles may be concentrated in an evaporator  16  so as to remove some of the water content. The resulting condensed distillers solubles (CDS) can then either be used in that form  26 , or may be used as inputs to other processes. In particular the CDS may be combined with wet grains from the stillage and then dried in a rotary drier  18  or a drum dryer  20 . The products of the drying process may be distillers dried grains with solubles  22  or, in the absence of added grains, distillers dried solubles  24 .  
         [0025]      FIG. 2  illustrates the production of protein blocks. Liquid solubles, distillers dried solubles, and condensed distillers solubles (collectively  28 ) are combined with molasses  30  and tallow  32  and the resulting syrup mixture is dehydrated using techniques that are standard in the block manufacturing industry. This step is indicated at  34  in  FIG. 2 .  
         [0026]     The standard technique, which is well-known in the industry, is as follows. The mixture is heated under reduced pressure  36  so as to promote the evaporation of water and the concentration of the mixture. The mixture is dried to a point where it is thick and viscous with a consistency similar to that of taffy. At this point additional ingredients such as vitamins, minerals, and proteins are added to the concentrated mixture so that such additives constitute less than half of the mixture while the evaporated syrups make up greater than one half of the final mixture. This step is indicated at  38  in  FIG. 2 . The mixture of evaporated syrups plus additives is then poured while hot into containers, indicated at  40 . in  FIG. 2 , where it is cooled, indicated at  42  in  FIG. 2 , and formed into blocks, indicated in at  44  in  FIG. 2 . The blocks are preferably between ten and two hundred fifty pounds. This step is indicated at  40  in  FIG. 2 . The mixture can also be subjected to pressure during block formation to improve the consistency of the blocks.  
         [0027]     In a preferred embodiment, distillers solubles from dry grind ethanol production serve as a replacement for nearly all or all of the molasses as a block ingredient. Distillers solubles are a good replacement for molasses because such solubles have a consistency that is very similar to that of molasses.  
         [0028]     Distillers solubles from a variety of sources can be used as starting material for making the protein blocks described herein. Solubles from either wet mill or dry grind ethanol production can be mixed with molasses and tallow, as described above, prior to the dehydration step. The molasses may be virtually any molasses including but not limited to cane molasses and beet molasses. The molasses is preferably beet molasses because it is the most “forgiving”, or easily mixed/and palatable, of liquids. The solubles can be by-products of ethanol production either for the beverage industry or from fuel-grade or other industrial-grade ethanol. The solubles can be in the form of liquid solubles, condensed distillers solubles, or distillers dried solubles. In addition, solubles from the fermentation of other grains, including but not limited to wheat, barley, sorghum, and rice, can be used to make the protein blocks described herein. It is important to note, however, that the grain by-products, if any, that are used will constitute only a minor portion of the final protein block, while the solubles will constitute the primary ingredient, preferably more than half of the weight of the final protein block. In addition, it is emphasized that the object of the present invention is to replace molasses completely, or to the furthest extent possible, as an ingredient of protein blocks. Therefore, higher concentrations of distillers solubles, also known as “tubs”, may be used.  
         [0029]     The process of making protein blocks, which are also commonly referred to as feed blocks, as described herein can be carried out batch-wise or through continuous flow processing. The depth of vacuum used during the dehydration process can be varied to control the rate and final extent of water loss from the distillers solubles mixture. The process can be varied to accommodate various packaging needs.  
         [0030]     The physical properties of the protein blocks are important. The blocks must be capable of being stored at ambient conditions for prolonged periods and must also be able to withstand varied weather conditions in the field. Especially under conditions of high temperature and humidity the blocks must not exhibit high levels of deliquescence, that is, absorb excessive amounts of moisture. Nonetheless, the blocks must not be so hardened as to make it difficult for livestock to eat from them: livestock must be able to consume the blocks in sufficient quantities so as to promote adequate feeding. Parameters that can be varied to control the stability and texture of the blocks, as well as the nutritional content, include the addition of separator byproducts, including but not limited to lipids, to the syrup mixture; the degree of pressure applied when curing the block; and the relative proportions of distillers solubles, molasses, tallow, and additives such as vitamins, minerals, and protein supplements. Finally, additional components may be added to control the extent of the Maillard reaction and Strecker degradation within the mixture, as these reactions have been known to limit the use of corn-based products in substantial quantities in the manufacture of animal feeds.  
         [0031]     The temperature at which the process is carried out can have an impact at various steps. The temperature can be altered during condensation of the syrup mixture to control the rate and extent of water loss. Temperature levels must also be controlled to prevent loss of nutrients and vitamins due to processes such as the Maillard reaction and Strecker degradation. Temperature levels must also be controlled to prevent scorching of the syrup mixture. The viscosity of the mixture will affect how easily it can be poured and formed into blocks and therefore can also be optimized. The syrup mixture preferably has a high viscosity. The viscosity of the syrup mixture increases as the moisture level of the mixture decreases. The pH of the solubles may also be adjusted to reduce the viscosity of the syrup mixture to a desired level.  
         [0032]     The research-scale block manufacturing plant, indicated at  46  in  FIG. 3 , includes a steam jacketed kettle with scraped surface agitators, a shell-in-tube preheater/cooker, and electronic temperature and vacuum sensors. The steam jacketed kettle operatures under vacuum or low temperature processing. In the preliminary study, the finished product included a syrup mixture  48  containing fifty percent (50%) condensed distiller&#39;s solubles and fifty percent (50%) beet molasses in the wet basis. The cooked basis included approximately twenty-eight percent (28%) distiller&#39;s solubles. The texture, color and physical characteristics of the block after cooling was comparable to blocks in which molasses is the sole ingredient.  
         [0033]     To maximize the amount of the new protein block (feed block) that each animal consumes, the composition of the blocks can be varied and the resulting preferences of the animals can be monitored to optimize feeding. Among the variables that can be measured in this regard are the animals&#39; preference for the distillers solubles-based blocks compared to other available blocks; variability in how much each animal consumes; consumptive behavior as it changes from one day to the next; and the amount of block material that is consumed when the animals are first introduced to the new blocks compared to the amount such animals consume after extended exposure to the new block material.  
         [0034]     In view of the foregoing, it will be seen that the several advantages of the invention are achieved and attained.  
         [0035]     The embodiments were chosen and described in order to best explain the principles of the invention and its practical application to thereby enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated.  
         [0036]     As various modifications could be made in the constructions and methods herein described and illustrated without departing from the scope of the invention, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative rather than limiting. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto and their equivalents.