Rice, 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). 

Stoger et al. [23] also observed that between species, the amounts of scFv per unit fresh weight were in the same range, and did not correlate with the total protein content in the plant. For example, even though pea is a much more proteinaceous crop than rice, the amounts of antibody measured as a percentage of TSP were considerably lower. 

Rice is the most important staple food crop in the world and has also emerged as the model cereal species (it is the only terrestrial plant other than Arabidopsis thaliana to benefit from a completed genome sequence, and extensive EST resources are also available). Rice has a lower annual grain yield than maize (6600 kg ha-1) and the grain has a lower protein content (8%), but like maize it is easy to transform and manipulate in the laboratory, a range of useful expression cassettes have been devel-... 

Lim, S. T, Lee, J. H., Shin, D. H., Lim, H. S. (1999). Comparison of protein extraction solutions for rice starch isolation and effects of residual protein content on starch pasting properties. Starch, 51, 120-125. 

Depending on the relative amylopectimamylose ratio found in the rice, the starch can exhibit a variety of gelatinized textures and strengths, as well as resistance to acid. Overall, there are several basic factors that affect starch performance. These factors, which include rice variety, protein content, method of starch production and modification, are described below. 

Figure 4. Total proteins secreted by callus from Tan-ginbozu rice seeds (Lane A), M202 rice seeds (Lane B), and M202 shoot (Lane C). 12.5% SDS-PAGE stained with Coomassie blue. Protein content reflects total protein secreted per g dry weight callus.

Rice oil is a minor constituent of rough rice when compared with the carbohydrate and protein content. Two major classes of lipids are present those internal within the endosperm and those associated with the bran. The internal lipids contribute to the nutritional, functional, and sensory qualities of rice (7). 

In Italy, where nearly everyone eats pasta, 50% of pasta stems from a wheat variety developed through mutation. In China extraordinary results were achieved with this method a certain type of rice now matures 24 days earlier, another type has a 20 cm shorter culm and in a third mutant a very high protein content was achieved (15.6%). Virtually hundreds, if not thousands, of such benefits have been developed over the last 10 years by artificially produced mutation in China alone where almost a tenth of the total crop acreage is under mutant-derived crops. 

Panda, Reddy, and Sharma (1991), in a 4-year study of how N affected production by nursery rice seedlings, found that Mo application increased yields in the resultant transplanted crop in only 1 of the 4 years. Others have reported increased leaf N concentrations and increased protein content following Mo application (Gupta and Basuchaudhuri, 1974). 

The physico-chemical properties of rice proteins are similar to those of casein. The main amino acid content of rice proteins is similar to that of casein and soy proteins. The rice proteins have favorable characteristics for wall material in microencapsulation. 

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. 

In the preparation of starch from rice, a product known as rice sludge or rice slump is left as a residue. The dried product has a crude protein content of about 280 g/kg DM and low crude fibre and oil contents, and is suitable for ruminants and pigs. 

The textural (stickiness and consistency on cooking) and physiochemical properties of rice could not be explained on the basis of the total amylose content but these properties correlated well with the insoluble amylose content. The protein content had no effect on these properties. A cross-linked amylose has been used as a substrate to determine the a- and )3-amylase activities of amylo-lytic preparations. ... 

Phytin content of whole seeds and protein bodies varies with species and cultivar. Examples of the chemical composition of the aleurone grains of rice and protein bodies (and isolated globoids) of cotton seed are shown in Table 2.7. Note, in particular, the higher phosphorus but lower protein content of the cereal aleurone grain in comparison with the dicot protein body. The concentration of the associated macronutrient elements can also be seen to differ. Qualitative as well as quantitative differences occur between the macronutrient compositions of different seeds, e.g. in C. maxima the globoid is rich in phosphate, potassium... 

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