Legumes protein content

The grain or pulse forms of legumes have a high total protein content (20-26%) and can therefore be used as a natural supplement to cereals. Pulses are normally deficient in the essential amino acids methionine and cystine but contain enough lysine, whereas cereals are deficient in lysine but contain enough methionine and cystine. 

Legumes Soybean High seed protein content, seed coat expression, low producer price Lower expression levels... 

Like alfalfa, the clover family (Trifolium spp.) consists of perennial legume plants that fix their own nitrogen. However, they suffer several limitations as general production crops for molecular farming, such as restricted perenniality, low protein content and the presence of high levels of condensed tannins which interfere with protein extraction. Despite these disadvantages, clovers are forage crops and are there-... 

The protein content of cookies was markedly influenced by the addition and protein content of the various legume flours (Figure 4). Each increment of peanut flour raised the total protein content in cookies by 1.5%. Increases of 1.4% occurred with soy flour and 0.5% with cowpea flour. 

Protein contents of selected oilseeds and legume seeds, and food protein ingredients prepared by various procedures, are shown in Table I. Amino acid contents and protein efficiency ratios (PER s)... 

Table I. Percent Protein Content of Various Fractions of Several Oilseeds and Legumes ...

On the basis of proteinate yields (Table II) and their protein contents (Table I), the recoveries of protein during wet processing were about 73% for both legumes, which was only slightly below the efficiency of the dry process. However, the losses of starch in the whey and wash solids were substantial, and starch recoveries averaged 77.5%. The yields of refined fiber were about 8% of the raw materials. Almost 30% of the dry matter from wet processing would have to be recovered from whey and wash extracts to make the process economical. 

The legumes have a high lysine content (7,32), which makes them an excellent complement to cereal proteins. Protein contents of pumpkin breads were 5,0, 5,6, 6,2 and 6,7% for loaves that had 0, 20, 35 and 50% Navy bean flour, respectively. 

Cow pea and urd bean, two common legumes are only slightly lower. An excellent review by H. D. Tindall of the leguminosae plants indicates most of their seeds have high protein contents, are directly consumable, and they are easily grown in tropical and subtropical climates (30). 

In terms of percentage of protein content of basic sources, the animal sources far excel the plant sources. For example, the protein content of some typical unfortified foods is as follows 20-30% for cooked poultry and meats 19-30% for cooked or canned fish 25% for cheese 13-17% 17% for cottage cheese 16% for nuts 13% for whole eggs 7-14% for dry cereals 8.5-9% for white bread 7-8% for cooked legumes and about 2% for cooked cereals. 

Duranti, M. and Gius, C. 1997. Legume seeds Protein content and nutritional value. Field Crops Res 53 31 -5. 

Mosse, J., Nitrogen to protein conversion factor for 10 cereals and 6 legumes or oilseeds—a reappraisal of its definition and determination—Variation according to species and to seed protein content. Journal of... 

Using sources of materials with higher protein content, such as legume flours and concentrates, the continuous phase of the melt becomes protein, with inclusions of carbohydrate. Proteins from different sources are even more different in their molecular architecture than are starches, resulting in quite different performance during extrusion. Necessarily, we will examine them separately. 

Soy, and Other Legume Proteins Two quite different product types have been constructed by extrusion, high-density flaked structures for meat analogues, and lower density and crispy products for high-protein snacks. The latter uses conditions similar to that of starch-based cereal extrusion to obtain low bulk density in the expanded product the former uses a higher water content in the extruder barrel and lower exit temperatures to obtain a dense material with open pores or even flaked structmes. For these two types of processes, molecular changes in the extruder barrel are not dissimilar. Post-die structuring of the extrudates determines final product properties. 

Methionine and cysteine, the sulfur-containing amino acids, are related meta-bolically. Methionine can be converted, in the body, to cysteine. In other words, methionine is the source of the sulfur atom in the synthesis of cysteine in the body Methionine nutrition is of occasional concern, because legume proteins have a relatively low methionine content. Therefore, legume-based diets, including those based on beans and peas, may not result in maximum growth rates for infants or animals. 

Saponins are glycosylated alkaloids, steroid, or triterpenes. They are in low concentrations in soybeans, 0.1—0.3% based on protein content, and legumes are the major source of saponins in the human diet (Lin Wang, 2004). 

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