No abstract

No abstract

No abstract

Soaking kinetics of dry faba beans was studied in the temperature range 20–65C, and at pH 3, 6, 9 and 12 by the method of weight gain until equilibrium conditions were attained. Increasing the soaking temperature from 20 to 35C resulted in a small increase in hydration rate constants as compared to that realized with further increase to 50 and 65C in the investigated range of pH. Soaking at 65C decreased the amount of water absorbed by the beans and the time at which equilibrium was attained. Beans soaked at alkaline pH exhibited higher hydration rates especially when hydration was carried out at ≥ 50C

Substitution of starch from barley, corn, oat, potato, rice or sorghum for prime wheat starch in the formulation of Arabic bread resulted in breads with signi®cantly (P`0.05) different textural attributes from regular wheat bread except for barley starch. Substitution of waxy barley starch (957 g kg À1 amylopectin) for wheat starch (279 g kg À1 amylopectin) resulted in bread that was not signi®cantly different from regular wheat bread when assessed in the fresh state. However, upon aging, the waxy barley starch-containing bread staled at a signi®cantly (P`0.05) faster rate than regular wheat bread. Breads made with waxy barley starch cross-linked with 50, 200 or 500 ppm phosphorus oxychloride showed higher enthalpy of melting (DH) upon aging and staled faster than the bread formulated with waxy barley starch. These ®ndings suggest that amylopectin retrogradation is one of the determinants of Arabic bread staling and that cross-linking promotes recrystallisation of amylopectin, possibly by keeping the polymer chains in close proximity. The rate of staling in breads formulated with cross-linked waxy barley starch decreased with increasing levels of cross-linking, possibly owing to restrictions in the degree of starch swelling.