Wheat amino acid supplementation

Seven diets were constructed from purified natural ingredients obtained from either C3 (beet sugar, rice starch, cottonseed oil, wood cellulose, Australian Cohuna brand casein, soy protein or wheat gluten for protein) or C4 foodwebs (cane sugar, corn starch, com oil, processed corn bran for fiber, Kenya casein for protein) supplemented with appropriate amounts of vitamins and minerals (Ambrose and Norr 1993 Table 3a). The amino acid compositions of wheat gluten and soy protein differ significantly from that of casein (Ambrose and Norr 1993). 

Reduced nitrogen retention was reported when chicks were fed rye diets (18). Supplementation of those diets with amino acids increased the retention of only the supplemented amino acids and not those contributed by the rye. These observations are compatible with the trypsin inhibitor hypothesis of other researchers (9,10). On the other hand, examination of the differences between endosperm and embryo and trypsin inhibitors of barley, wheat, and rye has revealed that, in contrast to certain trypsin inhibitors from leguminous seeds, those from the cereal grains appeared to be relatively weak, nonstoichiometric inhibitors of trypsin (19). 

Im, H.L., Ravindran, V., Ravindran, G., Pittolo, P.H. and Bryden, W.L. (1999) The apparent metabolisable energy and amino acid digestibility of wheat, triticale and wheat middlings for broiler chickens as affected by exogenous xylanase supplementation. Journal of the Science of Food and Agriculture 79,1727-1732. 

These compounds can be provided as a defined mixture or in the form of protein hydrolysates, such as lactoalbumin, or plant-derived hydrolysates, like colza (Deparis et al., 2003), soybean (Donaldson and Shuler, 1998 Heidemann et al., 2000 Ikonomou et al., 2001), wheat (Heidemann et al., 2000 Ikonomou et al., 2001 Ballez et al., 2004), and rice (Heidemann et al., 2000 Ikonomou et al., 2001 Ballez et al., 2004). Supplementation with yeast extract also provides additional amino acids. 

The protein efficiency ratio (PER) of sesame seed protein is 1.86 (35). The PER value can be raised to 2.9 when sesame seed protein is supplemented with lysine (36). El-Adawy (37) added sesame products including sesame meal, sesame protein isolate, and protein concentrate to red wheat flour to produce flour blends. It was found that water absorption, development time, and dough weakening were increased as the protein level increased in all blends however, dough stability decreased. Sesame products could be added to wheat flour up to 16% protein without any detrimental effect on bread sensory properties. The addition of sesame products to red wheat flour increased the contents of protein, minerals, and total essential amino acids the in vitro protein digestibility also increased significantly. 

The quality of a dietary protein may be increased by supplementing the diet with appropriate amino acids. This concept is illustrated by the study shown in Figure 6.29, which involved supplementation of a wheat-based diet with lysine. The chajtge in the quality of the diet was determined simply by measuring changes in the growth rate... 

The results from the study can be interpreted as follows. Lysine appears to be the first or most limiting amino acid of wheat protein. Maximal grow A occurred with reduced levels of dietary protein where the diet was supplemented with lysine. If lysine was the second most limiting amino add of wheat, the lysine... 

The mcjsl limiting amino acid of wheat protein is lysine. The study described earlier revealed the growth-promoting effects of supplementing wheat protein... 

Tables 7 and 8 illustrate the high value of yeast from petroleum-biological processes from the viewpoint of the physiology of nutrition. Among the essential amino acids, one may emphasize the high content of lysine (11.6%), which is almost absent in wheat flour. Thus, there is a physiologically valuable possibility of supplementing protein from higher plants. Moreover, the vitamin content is in some cases very much higher than in other foodstuffs.

The nutritive value of a protein resides in its amino acid composition. Thus, if a protein provides all the amino acids in exactly the required amount, the protein will be used effectively. Egg protein contains 60% of the indispensable and semi-indispensable amino acids. In contrast, whole wheat proteins contain only 40% of the indispensable amino acids. Consequently, even if whole wheat protein is supplemented with lysine, which is almost completely lacking, it still provides less indispensable amino acids per gram of nitrogen than all egg protein. Thus, the efficiency of a protein depends not only on the actual indispensable amino acids it contains, but also on the proportion in which these amino acids occur [24-26]. 

L-lysine is an alkali-amino acid that belongs to the aspartate branch in the biosynthesis of amino acids. It is an essential amino acid in animal nutrition. Many plant products used for livestock feed, such as wheat and com, are deficient in L-lysine, and thus, it must be added as a supplement in the form of soybean meal. The content of lysine in such products in comparison with soybean meal is shown in Table 2. 

There are several ways to supplement iron. The most practical way is by the enrichment of selected foods. The most common vehicles are dry-milled products such as refined white rice, maize meals, and wheat flours. The most important sources are ferrous sulfate (32.1% Fe), ferrous (22.3% Fe) or ferric citrate (17% Fe), ferric chloride (34.4% Fe), and elemental iron (97% Fe). The last source is the least expensive but the one that has the lowest availability. There are new sources of highly bioavailable iron that include chelated and amino acid forms. 

Reducing the level of dietary crude protein (CP) is an effective means to reduce nitrogen excretion but requires reliable information about the pigs requirements for potentially limiting amino acids (AA). Isoleucine (lie) may be limiting in low CP pig diets that are supplemented with lysine (Lys), threonine, methionine and tryptophan (Liu et al., 1999). The objective of this study was to estimate the optimum dietary standardized ileal digestible (SID) Ile Lys ratio in 25- to 40-kg pigs that were fed wheat-barley based diets. 

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