Investigating the spray drying damage mechanism of baijiu yeast with combined drying process and equipment

Abstract Traditional drying processes used to dry high-quality baijiu yeast-Sporidiobolus johnsonii A do not offer advantages such as high efficiency, high survival rate, and low energy consumption. Therefore, we investigated the damage inactivation mechanism of S. johnsonii A for the spray drying process. Subsequently, the combined drying process and equipment for spray + vacuum-microwave-vibration were designed. The results reveal selective permeability damage and collapse owing to gel and anti-hexagonal phase transitions of the cell membrane, resulting in S. johnsonii A inactivation and massive inactivation at 52 °C with a water content of 0.21 and at 71 °C with a water content of 0.07, respectively. The combined drying process developed in this study successfully dried S. johnsonii A with high efficiency (1.1 h) and excellent quality (85.4 ± 2 %).