Protein fractions, namely arachin, conarachin I, and conarachin 11, from peanut (Arachis hypogaea L.) were isolated to homogeneity and their functional properties studied. Bulk density and water absorption and fat absorption capacities were measured. Solubility of the fractions varied as a function of pH, and more than 95% of protein was soluble at pH below 2.5 and above 7.0. The presence of NaCl decreased the solubility a t low pH. The total protein of peanut had a value of 1.11 for emulsifying activity (EA), while arachin, conarachin 11, and conarachin I had values of 0.90,1.05, and 1.11, respectively, and their emulsifying stability (ES) values ranged from 72 to 300 s. The effects of variables such as protein concentration, pH, and NaCl concentration on the emulsifying properties of peanut protein fractions were studied. The foaming capacities of the fractions before and after hydrolysis with a-chymotrypsin were in the order total protein > arachin I conarachin I > conarachin I1 and total protein > conarachin I > arachin > conarachin 11, respectively. The foam stability of enzyme-hydrolyzed fractions followed the order conarachin I > total protein > arachin > conarachin 11.

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A B S T R A C TStudies on the proteins offive varieties of kodo millet showed that there are hardly any varietal differences. Fractionation of the proteins showed that glutelin is the major storage protein. The amino acid compositions of the protein of the five varities of kodo millet and the individual protein fractions of two varieties were determined. Lysine is the most limiting amino acid followed by methionine and cystine. There is no significant negative correlation between lysine levels and protein content. Sodium dodecylsulphate polyacrylamide gel electrophoresis patterns indicate great similarities in the different varieties.

Total protein from five varieties of Japanese barnyard millet (Echinochloa frumentacea) was separated into albuminlglobulin, prolamin and glutelin fractions. The protein fractions were examined by sodium dodecylsulphate polyacrylamide gel electrophoresis. Total protein of the varieties ranged from 110.5 to 139.3 mg g-I of which 11.3-17-2% was albumin/globulins, 6.8-9.3% prolamins, 7.5-11.6% prolamin-like, 5.9-9.1 % glutelin-like and 39-3-54.4% true glutelins. Amino acid analyses of the total protein showed that the varieties had essentially the same amino acid composition. With the exception of lysine the amino acid levels adequately matched the provisional FA0 scoring pattern. The amino acid composition of the protein fractions was also very similar. Electrophoretic analysis showed that the albumin/globulin fraction contained three or four components; the prolamin and glutelin fractions each had five components. The glutelin fraction had higher molecular weight components than the other two fractions.

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