Effects of Pichia guilliermondii and Hot Air Treatment on the Postharvest Preservation of Red Fuji Apple Quality Attributes

The effects of individual and combined Pichia guilliermondii (at 1 × 10⁸ CFU mL^-1) and hot air (at 38°C for 96 h) treatments on the three major postharvest diseases Botrytis cinerea, Penicillium expansum, and Colletotrichum gloeosporioides, as well as the quality and antioxidant content of Red Fuji ( Malus pumila var. domestica) apple fruit, were investigated in this work. Results suggested that the combined hot air and antagonistic yeast ( P. guilliermondii) treatment effectively and completely inhibited the infection of apple fruit wounds by the three major postharvest diseases. Furthermore, apple fruit treated with antagonistic yeast or heat alone maintained better quality, which included mass loss, firmness, solid/acid ratio, and ascorbic acid content, than the control. The combination of the two treatments yielded the optimum apple quality. Moreover, the combined hot air and P. guilliermondii treatment also maintained or enhanced the antioxidative enzyme activities and total phenolic content of apple fruit. All results demonstrated that the combined antagonistic yeast and hot air treatment maintained the postharvest freshness of apple fruit.