Acrylamide resulting from heat-time treatment in Cajanus cajan, a neglected and underutilized legume

Abstract

The influence that heat-time treatment has on the concentration of acrylamide in roasted Cajanus cajan was analysed. The study focussed on optimising the roasting conditions using Response Surface Methodology
(RSM) to minimise concentration of acrylamide in roasted Cajanus cajan. The raw Cajanus cajan was soaked in solvent containing an additive of either citric or phosphoric acid in the range 0.1 – 1.0 (g or mL). The soaked Cajanus cajan was then dried and roasted. The roasting conditions used were temperatures from 80 – 120 ºC and time of 10 - 60 min. Response Surface Methodology (RSM) analysis of the data showed that the concentration of acrylamide significantly increased as the roasting temperature and roasting time for processing increased (p<0.05). Citric acid and phosphoric acid used as additives in soaking the Cajanus cajan had no significant effect on acrylamide formation. The optimization of process parameters to give low concentration of acrylamide resulted in roasting temperature of 80 ºC, roasting time of 10 min and 0.1 g of citric acid with the maximum desirability of 0.972. Acrylamide concentration in roasted Cajanus cajan produced with optimized condition (80 ºC, 10 min and 0.1 g citric acid) was 1.757 g/kg.

Keywords: Acrylamide, Heat-time treatment, Response Surface Methodology, Cajanus cajan