Rapeseed freeze-dried meal and water-soluble fraction were acylated with succinic and acetic anhydride and methylated with formaldehyde at different concentrations of these reagents, and changes in phytic acid, phenols, glucosinolate content, and functional properties were determined. In general, the greater was the extent of acetylation, the lesser was the extractability of phytic acid, phenols, and glucosinolates in both preparations. Water absorption and fat absorption capacities were enhanced by acetylation, but succinylated meal absorbed a maximum amount of oil at a minimum level of modification. Nitrogen solubility, foaming capacity, and viscosity were markedly improved by succinylation. Emulsifying properties were adversely affected by acylation, while methylation proved to be stimulatory. Modified water-soluble fractions had low content of antinutritional constituents, and acylated extracts showed better emulsifying and foaming properties. Keywords: Antinutritional factors; chemical modification; functional properties; rapeseed meal; water-soluble fraction

Cereal Chem. 79(6):834-837Amaranth meal is a rich source of proteins, carbohydrates, and minerals with a low amount of anti-nutritional factors. It exhibits good functional properties. The effect of NaCl and NaHCO 3 salts and pH level on the functional properties of amaranth meal was studied. The water absorption capacity and protein solubility were improved in the presence of the salts. Protein solubility was high at extreme pH values and minimum at pH 4. Foaming capacity was poor in the presence of the two salts, while foam stability was better at lower concentrations of NaCl (0.2-0.6M). Changes in pH had a pronounced effect on the foaming properties of amaranth meal. Salts did not change the emulsification properties but significantly increased the relative viscosity of amaranth seed meal at higher concentrations of NaCl and NaHCO 3 (0.6-1.0M). Relative viscosity was highest at pH 10 and lowest at pH 4. Functionality has been defined as any property of a food ingredient, except its nutritional value, that has a great impact on its utilization. The functional properties directly or indirectly affect the processing applications, food quality, and ultimately their acceptance and utilization in food and food formulations. The use of soybean as a source of nutritious food and substitute for meat is due to the knowledge of the functional properties of its flour and other products (Volkert and Klein 1979).Amaranth is the world's most nutritious pseudo-cereal grain with multiple uses (Teutonico and Knorr 1985). It is one of those rare plants whose leaves are eaten as a vegetable while the seeds are used as cereals. Amaranth grows vigorously; resists drought, heat, and pests; and adapts readily to new environments, including some that are inhospitable to conventional cereal crops.Amaranth produces a higher yield of seeds than most common cereals. With a protein content of 16%, amaranth seed compares well with the conventional cultivars of wheat (12-14%), rice (7-10%), maize (9-10%), and other widely consumed cereals (Chang and Sosulski 1985). Amaranth proteins have nearly twice the lysine content of wheat protein, three times that of maize, and as much as milk, the standard of nutritional excellence. With so much to its credit, amaranth crops are still playing a secondary role to crops like rice and wheat on our dinner plates. Therefore, the challenge is to incorporate it into existing food formulations to modify the functional and nutritional qualities, and to create new products from it.A good amount of work has been done on the proximate composition, nutritional value, and genetic potential of this crop (Raina and Datta 1992; Bejosano and Corke 1998), but very little is known about its functional attributes. This investigation deals with the functional properties of amaranth meal in the presence of salts and at various pH levels, to evaluate its utilization in various products. The effect of salts is important because salts are integral constituents of food product formulations; concentrations of 0.2-0.3M are commo...

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Different processing treatments were applied to rapeseed and sesame seed meals, and the functional properties of these products were assessed. All treatments except puffing for both meals and pressure cooking in sesame meal increased water absorption capacity (WAC). Fat absorption capacity (FAC) of rapeseed meals was enhanced significantly by all treatments. The full-fat meals of both sources showed maximum protein solubility when fermented and minimum protein solubility when pressure-cooked. Germinated and microwave-cooked meals enhanced foaming properties of rapeseed meals. Heat treatments, except microwave cooking, considerably reduced emulsifying properties of both meals. Fermentation and germination increased the specific viscosity of rapeseed meals, whereas processed sesame meals showed lower viscosity than dry sesame meals.

Antinutritional factors, viz. glucosinolates, phenols, and phytic acid, decreased with germination of rapeseed. Protein content declined during the first 24 h after imbibition and thereafter increased. Phytase activity increased with germination with a parallel decrease in phytic acid content. Two phytase fractions were separated during elution on DEAE-cellulose column, showing purifications of 26.75- and 19.96-fold, respectively. Optimum pH and temperature for both fractions were 5.2 and 50 °C, respectively. Enzyme stability decreased considerably after 50 °C, and phytase 2 was stable for a longer time. Mn, Co, Ca, and EDTA promoted the enzyme activity, whereas ions of Zn, Fe, Cu, fluoride, molybdate, and arsenate were inhibitory. Keywords: Antinutritional factors; characterization; germination; phytase