Inactivation of Surface Microorganisms of Moth bean (Vigna aconitifolia) by Micronization and Changes in its Physico Chemical and Rheological Properties

Abstract

Moth bean seeds (Vigna aconitifolia) were micronized at different temperatures viz 150, 250, 300, 350 and 400⁰ C to study the efficacy of treatment to check the surface microorganisms. Surface microbes were found to decrease by 90 % when micronized at 300⁰ C with more than 85% germination at this temperature. Functional and rheological properties were not affected much up to the treatment of the seeds at 300⁰ C. Above this temperature, significant changes (p≤0.05) in functional and rheological properties were observed. Antinutritional factors viz  phytic acid, trypsin inhibition activity (TIA), tannins and saponins decreased significantly (p≤0.05). Total phenols and total flavonoids also found to decrease slightly but significantly (p≤0.05) during micronization which correlated with the decrease in antioxidant activity as observed by DPPH radical scavenging methods. Micronization of moth bean at 300⁰ C can be used effectively for the surface inactivation of microbes without affecting the seed quality deleteriously.

Keywords: Moth bean, micronization, surface inactivation, rheology, physico-chemical changes