Impact of Gamma Irradiation on Physicochemical, Technological, Antioxidant and Microbiology Properties of Whole Sorghum Flours

This study aimed to evaluate the effect of gamma irradiation (GI) on the physicochemical, technological, antioxidant and microbiological characteristics of different whole sorghum flours (WSF), as well as to characterize the profile of chemical constituents by paper spray mass spectrometry (PS-MS). The doses applied interfered in the staining characteristics of the evaluated flours, providing the darkening of the same. For the other physicochemical, technological, and antioxidant parameters, no significant influence of the process was observed. The fingerprint obtained in both ionization modes had not been influenced by irradiation, being flavonoids, phenylpropanoids, amino acids, benzoic acid derivatives, carboxylic acids, and sugars tentatively identified. In microbiological terms, there was a reduction of molds, yeasts, and Bacillus cereus in irradiated WSF compared to control (non-irradiated). Therefore, the application of low doses of gamma irradiation represents an advantageous alternative for the conservation of WSF and maintenance of bioactive compounds identified by the PS-MS technique.

本研究旨在评估γ辐照（gamma irradiation, GI）对不同全高粱粉（whole sorghum flours, WSF）的理化、工艺、抗氧化及微生物学特性的影响，并采用纸喷雾质谱法（paper spray mass spectrometry, PS-MS）对其化学成分谱进行表征。所施加的辐照剂量会对受试面粉的着色特性产生干扰，使其色泽变暗。针对其余理化、工艺及抗氧化相关参数，未观察到该处理带来的显著影响。两种电离模式下获取的质谱指纹图谱均未受辐照影响，初步鉴定出的成分包括黄酮类、苯丙素类、氨基酸、苯甲酸衍生物、羧酸及糖类。微生物学层面而言，与对照组（未辐照样品）相比，辐照后的全高粱粉中霉菌、酵母菌及蜡样芽孢杆菌（Bacillus cereus）的数量均有所减少。因此，采用低剂量γ辐照是实现全高粱粉保藏、保留经PS-MS技术鉴定出的生物活性成分的一种优势可行方案。