Effects of combination of UV-B irradiation and drying on the physicochemical properties of key components and processing quality of germinated whole wheat flour

Abstract

The germination of wheat promotes the synthesis of bioactive compounds, thereby improving the nutritional quality of wheat-based products. However, the activation of specific bioactivators can result in the degradation in processing quality of germinated wheat. This study investigated the physicochemical properties of key components and the processing quality of germinated wheat flour subjected to UV-B irradiation combined with different drying conditions. Germinated wheat flour under UV-B irradiation exhibited significantly increased total phenols and promoting phenolic acids accumulation from bran layer to endosperm. High-temperature (80 °C) or sequential (45/80 °C) drying induced a further rise in DPPH scavenging ability, enhanced starch crystallinity and prevented the reduction in viscosity. High-temperature drying facilitated the formation of intermolecular disulfide bonds and the aggregation of high-molecular-mass proteins. Additionally, UV-B irradiation suppressed the deterioration of mixing properties in germinated dough, and dough stability was even higher than that of ungerminated dough when paired with high-temperature drying. Furthermore, sequential drying showed the greatest improving effect on germinated noodle texture. In conclusion, the use of UV-B irradiation combined with drying conditions holds significance for processing nutrient-maintained germinated wheat products.