Cold plasma processing of sesame milk: Changes on physicochemical properties, nutrition, anti-nutritional factors, protein structure and allergenicity

Abstract

In the recent decade, consumers have preferred plant-based (vegan) foods due to the maintenance of environmental sustainability. However, some of the plant-based foods have a demerit of the presence of anti-nutritional factors and allergenic components. Thus, the current study was aimed at reducing these demerits in sesame milk without spoiling the quality by the use of green, novel, cold plasma technology. This study investigated the effect of a low-pressure plasma (LPP) system's power levels (25, 60 and 120 W) on the physicochemical properties, nutritional changes, anti-nutritional factors, protein structure and allergenicity of sesame milk. No prominent or undesirable changes were observed in the physicochemical properties; conductivity increased with the increase in power level (59.23 mS/cm in control to 61.67 mS/cm at 120 W). The lipoxygenase activity was reduced to 67 % for samples treated at 120 W LPP power. The anti-nutritional factors phytates (25 % reduction from 1.47 mg/g in control to 1.09 mg/g in 120 W) and oxalates (10 % reduction from 39.14 µg/g in control to 35.18 µg/g 120 W) decreased slightly during plasma application. The DSC and FTIR analysis revealed that plasma-induced oxidation changed the secondary protein. However, there was no significant reduction (5 %) in allergenicity during LPP treatment. Though, the plasma application was effective in reducing the enzyme activity and antinutritional factors, no drastic reduction or complete elimination was observed. An increase in power level or exposure time in future could aid in the reduction of allergenicity in sesame milk.