Modifications in the physicochemical properties of flour “fractions” after Pulsed Electric Fields treatment of thermally processed oat

Abstract

This research aimed to investigate the physicochemical properties of thermally processed oat flour (TPOF) “fractions” (Supernatant, Top/S1, Middle/S2, Bottom/S3) after Pulsed Electric Fields (PEF) treatment of TPOF at 2 and 4 kV/cm between 50 and 451 kJ/kg. Supernatant from PEF-treated TPOF displayed a generally higher β-glucan content than untreated TPOF. No major changes were observed in chemical composition (in terms of total starch, protein, and fat contents) amongst “fractions”. However, S1 obtained from PEF-treated TPOF exhibited an increase in particle size, while both gelatinisation enthalpy and percent relative crystallinity were significantly lower compared to untreated counterpart. S1 from PEF-treated TPOF at 422–451 kJ/kg also manifested severe changes in granule morphology. S2 exhibited the highest gelatinisation enthalpy and S3 registered the least degree of observed changes in particle size. Findings of this study suggest the potential of PEF treatment application to produce oat “fractions” with varying physicochemical properties. Industrial relevance: This study provides indispensable scientific information that could be utilised to further investigate industrial production of customised fractionation of oat flour with targeted physicochemical properties through PEF treatment. This opens new opportunities to strategically diversify the range of oat flour ingredients based on their targeted unique properties in the food industry.