Protein meal processing

Food combining (the Hay diet ) advises against combining starch and sugar with protein and acid fruits. At least 4 h should separate starch and protein meals. Protein, starch, and fats are eaten in small quantities, and all refined and processed foods are prohibited. This diet is said to improve arthritis and digestive problems. 

Several reports show that properly processed whole soybeans can be used effectively in broiler (Parvu et al., 2001) and layer (Sakomura et al., 1998) diets as a partial or complete replacement for soybean or other protein meals, although the digestibility of this ingredient may be more variable than with conventional soybean meal (Opapeju et ah, 2006). 

Extraction. The raw material for the fat and oil industry comes from animals (hogs, sheep, and fatty fish) fleshy fruits (palm and olive) and various oilseeds. Most oilseeds are grown specifically for processing of oils and protein meals. 

Processing methods developed over the years are designed to extract canola oil from the seeds to produce a high-quality raw oil for further processing and a high-quality protein meal as an animal feed. 

The production or import of oilseed in a particular country will be determined by whichever oilseed product is in the greatest demand. For example, in Japan, the oilseed processing industry will consider the current domestic need for oils and fats, international markets for oils and fats, and domestic and international demand for protein meals before a decision is made as to which oilseed will be imported. Basically, when domestic need for protein is high, soybean will be imported and processed. If domestic demand for oil is the driving force, Japan imports canola for processing (151). 

Cake or meal from oil extraction contains 40-50% protein when processed in a screw press and 56-60% protein after solvent extraction. Sesame products have a pleasant flavor and contain high levels of methionine and cysteine. The flour produced from sesame meal has a high nutritive value compared to other oilseed flours (75). 

There are four primary reasons why the mechanical extraction process is still selectively used. First, the mechanical extraction process can be furnished in very small scale, as low as 10 tons per day. The capital cost for small mechanical extraction facilities is considerably less than small solvent extraction facilities. In remote locations, freight differential can compensate for higher operating costs and lower yields. Second, there is a niche, high-value market for natural oils that have not been in contact with solvents or chemicals, requiring the use of mechanical extraction. Third, mechanical extraction can create a high bypass protein meal for ruminant animals that sells at a price premium over solvent extracted meal. Finally, mechanical extraction is often considered more reliable than solvent extraction when processing difficult materials (copra and palm kernel) in hot, tropical climates. 

Although mechanical pressing of soybeans accounts for a only very small percentage of soybean processing, it is used by many farm cooperatives or family-owned on-farm operations in the US, primarily to produce protein meals for use as animal feed. 

We are pleased to offer to students, researchers, industry practitioners, and all who are interested in the worlds most versatile crop, the most complete and authoritarian book on soybeans Soybeans Chemistry, Production, Processing and Utilization. This is one of several books comprising the AOCS Monograph Series on Oilseeds published by AOCS Press of the American Oil Chemists Society, which provides the latest and most comprehensive information on plant sources of fats, oils and protein meals of vital importance in feeding the world and providing the many biobased products we consume every day. 

Soybeans are an important source of edible oil, but many have argued that soybean is actually a protein crop because 60-70% of the returns in processing soybeans is due to the sale of meal (Table 11.1). No other oilseed contains as much protein. Thus, processes used to extract soybean oil are designed to maximize meal quality for use in livestock feeds. 

Edwards, III, H.M. M.W. Douglas C.M. Parsons D.ff. Baker Protein and energy evaluation of soybean meals processed from genetically modified high-protein soybeans. Poult. Sci. 2000, 79, 525-527. 

Since swine and poultry require low fiber for optimum growth and feed conversion efficiency the protein enhanced meals are preferred. However, since no satisfactory commercial method of dehulling rapeseed has been devised to date the rapeseed fiber accompanies the other seed constituents through the process emerging with the protein meal. Grinding of the meal followed by air classification has been only moderately successful in reducing the fiber content of rapeseed meal. The industry has not as yet installed any significant capacity for this purpose. 

NUTRITIONAL VALUE OF RAPE. The seeds contain 40 to 45% oil and 25% protein. When processed, rapeseed yields about 40% oil and 50% oil meal which ranges from 32 to 40% protein. 

The extracted cake is ground to yield a 20 to 42% protein meal, with the higher protein content obtained from decorticated (dehulled) seed. Meal produced by the solvent method contains about 1% fat vs 5% when the expeller process is used. Safflower meal is of good quality, although somewhat deficient in lysine and methionine. 

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