Effect of particle size change based on ultrafine grinding on the nutrition, physicochemical properties, and functional properties of selenium-enriched oyster mushroom.

This study employed ultrafine grinding technology to produce Selenium-enriched Pleurotus ostreatus (SP) powders with different particle sizes. Their infrared spectra, micromorphology, hydration properties, antioxidant activity, adsorption characteristics, in vitro selenium release, and hypoglycemic activity were systematically investigated to elucidate the relationship between mesh size and the nutritional density, physicochemical properties, and functional characteristics of SP. Compared to conventionally ground 40-mesh SP, the 300-mesh ultrafine powder, The ultrafine powder showed finer, more uniform particles. Extractable efficiency of polysaccharides, soluble proteins, and soluble dietary fiber increased by 83.53, 90.04, and 82.69%, respectively. Cholesterol and glucose adsorption capacities rose by 101.21 and 31.04%, while α-amylase and α-glucosidase inhibition rates increased by 90.91 and 94.71%. Selenium release in simulated gastric and gastrointestinal fluids improved by 34.57 and 52.61%. Overall, ultrafine grinding enhanced the extractable efficiency of nutritional components, selenium bioaccessibility, adsorption properties, and in vitro hypoglycemic and hypolipidemic activities, representing an effective modification strategy for developing high-value functional products.