Study on the effect of pilot scale roasting conditions on the physicochemical and functional properties of maize flour (Cv. Bio 22027)

摘要

Maize kernels were subjected to pilot scale roasting treatment for different time (10–35 min) and temperature (170–200 ℃) combinations using a full factorial design. The changes in physicochemical (moisture content, browning index, hardness, bulk density, degree of gelatinization), and functional properties (in vitro protein digestibility [IVPD] index, water/oil absorption capacity [OAC]) were measured as responses which were fitted to quadratic models. The optimized conditions obtained by roasting for 25 min at 190 ℃ yielded a desirability of 0.62 with a moisture content (4–5%), hardness (130–135 (N)), browning index (63.57–65.50), bulk density (0.64– 0.66 g/cc), IVPD index (72–74%), degree of geltinization (58.85–60.82%), and a water/OAC (1.85/ 2.29 g/g). The presented pilot scale optimization scheme of roast maize kernels could serve as a useful guide to cottage-scale food manufacturers during establishment of any pilot scale unit.