Effects of hot-air drying temperature on drying characteristics and color deterioration of rape bee pollen

values. Browning index and 5-HMF content increased with increasing drying temperature. The relative content of antheraxanthin increased 230 % at 70 °C while lutein and zeaxanthin decreased by 74 and 81 % than that of fresh (non-heated) pollen. The contents of 3-deoxyglucosone, 1-deoxy-2,3-pentosulose, antheraxanthin, and lutein were related to the color deterioration in HAD process in rape bee pollen. This work is of great practical significance to provide scientific basis for quality optimization of bee pollen in the drying process.