Barley protein content

Our group has used twin-screw extrusion to produce many texturized whey-fortified puffed snacks. Whey protein has been blended with barley flour, com meal, rice flour, and wheat starch prior to extrusion, leading to corn puffs with a protein content of 20% instead of the usual 2% (Onwulata et al., 2001a). 

FIV152 Kanauchi O., T. K. Agata, and T. Fushiki. Mechanism for the increased defecation and jejunum mucosal protein content in rats by feeding germinated barley foodstuff. Biosci... 

Hull-less barley varieties have been developed, in which the hull separates during threshing. These varieties contain more protein and less fibre than conventional barley, and theoretically should be superior in nutritive value to conventional barley. However, Ravindran et al. (2007) found that the ME (N-corrected basis) was similar in hull-less and hulled barley. The chemical composition of six Brazilian hull-less barley cultivars was studied by Helm and de Francisco (2004) and reported as follows. The highest constituents were starch (575-631 g/kg), crude protein (125-159 g/kg) and total dietary fibre (TDF 124-174g/kg), the starch and crude protein contents being in agreement with those previously reported for Swedish (Elfverson et al., 1999) and Canadian (Li et al., 2001) varieties. The other reported values (g/ kg) were ash content 15.1-22.7, ether extract 29.1M0.0, starch 574.6-631.4, insoluble dietary fibre 80.7-121.6, soluble dietary fibre 43.0-64.5 and p-glucan 37.0-57.7. 

Rye has an energy value intermediate to that of wheat and barley, and the protein content is similar to that of barley and oats. However, its nutritional value is reduced by the presence of several ANFs such as P-glucans and ara-binoxylans which are known to cause increased viscosity of the intestinal contents and reduced digestibility, and other undesirable effects such as an increased incidence of dirty eggs. These effects are more pronounced in hot and dry environments, which accentuate the rate of cereal ripening prior to harvest (Campbell and Campbell, 1989), as occurs in Spain and other Mediterranean countries. Rye may also contain ergot, which is a toxic fungus that reduces poultry health and performance. 

The use of many varieties and crosses to improve yield and grain quality in triticale as well as adaptation to local conditions has resulted in a variation in nutrient composition. The protein content of newer varieties is in the range of 95-132g/kg, similar to that of wheat (Briggs, 2002 Stacey et al, 2003) Typical lysine contents (g/kg) reported by Hede (2001) from work in Mexico and Ecuador are triticale 50.4, barley 29.4, wheat 43.0 and maize 22.7. 

In this country, the ordinary six-row barley is the kind most abundantly produced, being raised extensively in the States of the Mississippi Valley. Its relatively high protein content causes it to produce malt of high diastatic power, and thus fits it especially to use in the distillery. 

TABLE 2.5 Protein content, protein digestibility, lysine and leucine contents and PDCAASs of normal and improved protein quality lines of sorghum, compared to wheat, maize, barley, and pearl millet (data from several sources as indicated)... 

In many of the intensive rice-growing areas of the world, particularly Asia, this straw is used as a food for farm animals. Its protein content and metabolisable energy value are similar to those of spring barley straw. It has an exceptionally high ash content, about 170 g/kg DM, which consists mainly of silica. The lignin content of this straw, about 60-70 g/kg DM is, however, lower than that of other cereal straws. In contrast to other straws, the stems are more digestible than the leaves. 

Pig and poultry diets based on cereals and vegetable protein sources are now routinely supplemented with L-lysine hydrochloride (supplying 780 g lysine/kg), dl-methionine and L-threonine. A diet for a finishing pig, which has to contain 10 g lysine/kg, required a combination of 750 g barley and 250 g soya bean meal/kg, and this mix has a crude protein content of 185 g/kg (see Appendix 2, Table A.2.2.2). With the inclusion of 2 g of lysine hydrochloride, the same lysine content can be achieved with a mix of 808 g barley and 190 g soya bean meal, and the protein content is reduced to 165 g/kg. Such reductions in crude protein content have maintained a balanced supply of amino acids and resulted in improved rates of liveweight gain and food conversion efficiency. It is important that the supplementary acids are not used excessively to satisfy the animal s requirements, since this may bring about an undersupply of other essential amino acids. 

Marchylo and Kruger [26,52] developed and optimized conditions to separate barley and malt prolamins (hordeins) by RP-HPLC, and used these methods for cultivar identification based on qualitative and quantitative differences. Elution profiles were largely independent of growth location, year, and protein content. Identification of barley cultivars by hordein lE-HPLC was also reported [164], Barley HPLC varietal identification was reviewed by Marchylo [165],... 

Grain crops, specifically cereal crops, are major feedstocks for the food and fermentation industry because of their high starch and protein content. Cereal crops are by far the most important crops cultivated globally. In 2009 about 2.5 billion tonnes of cereals were produced worldwide (FAO, 2010). Wheat, com, barley and sorghum are the common starch sources that have been traditionally used in food and industrial bioproduct manufacturing. Straw and stocks from cereal crops are also important as lignocellulosic feedstock for bioproduct manufacturing. 

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