2001 AACC Annual Meeting Charlotte, North Carolina October 14-18, 2001 Charlotte Convention Center

The necessity of obtaining new products with variety of functional attributes has led to apply techniques of modification in starches of non-traditional sources. These non-traditional sources are important in the elaboration of foods. Since starches contribute to the structure, texture and consistency, besides helping to reduce the costs for substitution of conventional ingredients. The chemical cross-linking modification consists of the introduction of phosphate groups like bridges or crossed connections among the neigh boring molecules. With this modification, structural and functional changes are produced on the starch. In this study some functional properties of the cornstarch modified by cross-linked were evaluated according to Whistler and Paschall 1967, with some variations. The process of modification of the starch was carried out using different pH (9.0; 6.8, and 6.7) and temperatures (122°C, 122°C, and 152°C), being obtained three lots of modified starches. Samples of each one of the lots were evaluated in their rheological and physicochemical properties. Water absorption, solubility and swelling power were determined according to Whistler, 1964. The apparent viscosity was performed using the viscosímeter Brookfiel according Whistler and Paschall (1967). Gelatinization profiles using the Brabender amylograph according to the A.A.C.C. (1993) and Mazur et al, 1957. The variation of the temperature and of the pH does affect the functional behaviour of the cornstarch. The modified starches show significant differences in their rheological and physicochemical properties with regard to the native one, for the effect of the temperature and pH variations. The viscosity was increased and differences were also observed in water absorption, solubility, and swelling power. The properties evaluated in the starches will allow elucidating their possible use at industrial level.