Disinfestation of chickpea and green gram from Callosobruchus maculatus adults through hot air assisted microwave heating system

Abstract

Pulse bruchid-infested samples of green gram (Vigna radiata) and chickpea (Cicer arietinum) having different moisture contents (7.5–9.5% wb) (1 cm bed depth) were exposed to microwave–hot air treatment for different exposure times (3 min 20 s to 6 min) and hot air temperatures (40–60 °C). Protein content, cooking time, textural kinetics, color and viability of the treated samples were analyzed, and techno-economic feasibility analysis was carried out for the process. Hundred percent mortality of adult insect (Callosobruchus maculatus) was achieved immediately, at an air temperature of 60 °C with microwave exposure period of 6 min at 2900 W power level. All the three processing parameters, i.e., moisture content, period of exposure and hot air temperature, were found to have significant effect on the mortality of pulse bruchids for both chickpea and green gram. Negligible differences were observed between the control and treated samples with respect to protein content for both chickpea and green gram. Cooking time, textural hardness, L value, greenness and viability of treated samples were lower than control sample. Cost of the treatment works out to be INR 6.28–7.07 per kg which is likely to come down with economics of scale.