Tian Yiming, Li Lamei, Wang Rui, Ji Ning, Ma Chao, Lei Jiqing, Guan Wenqiang, Zhang Xu
College of Food and Pharmaceutical Engineering, Guiyang University, Guiyang 550005, China.
Tianjin Key Laboratory of Food Biotechnology, College of Biotechnology and Food Science, Tianjin University of Commerce, Tianjin 300134, China.
Foods. 2023 Aug 24;12(17):3197. doi: 10.3390/foods12173197.
Soft rot is a severe postharvest disease of kiwifruit that causes enormous economic losses annually. In this study, we aimed to explore an effective pullulan-based active coating, incorporating food additives to reduce soft rot and extend the shelf life of cold-stored kiwifruit. The results showed that 1 g/L potassium metabisulfite could completely inhibit the mycelial growth of sp., , sp. and sp., which were the primary pathogens of kiwifruit soft rot. Furthermore, the pullulan coating, combined with a 10 g/L potassium metabisulfite group, had a decay rate 46% lower than the control (CK) group and maintained fruit quality at the end of shelf life. The retention of physicochemical properties such as soluble solid content (SSC), firmness, weight loss and respiration rate also confirmed the efficacy of the treatment. In addition, at the end of shelf life, pullulan coating, combined with potassium metabisulfite, increased the accumulation of total phenolic content (37.59%) and flavonoid content (9.28%), maintained a high energy charge (51.36%), and enhanced superoxide dismutase (SOD) (6.27%), peroxidase (POD) (62.50%), catalase (CAT) (84.62%) and phenylalanine ammonia lyase (PAL) (24.61%) enzyme activities as well as initiating the upregulation of their gene expression levels. As a result, the disease resistance of fruit was improved, and the occurrence of soft rot was delayed. Overall, this study demonstrated that using the pullulan-based active coating incorporating potassium metabisulfite treatment effectively controlled soft rot and retarded the senescence of postharvest kiwifruit.
软腐病是猕猴桃严重的采后病害，每年造成巨大经济损失。在本研究中，我们旨在探索一种有效的基于普鲁兰多糖的活性涂膜，加入食品添加剂以减少软腐病并延长冷藏猕猴桃的货架期。结果表明，1 g/L焦亚硫酸钾可完全抑制猕猴桃软腐病的主要病原菌—— 菌、 菌、 菌和 菌的菌丝生长。此外，普鲁兰多糖涂膜与10 g/L焦亚硫酸钾组相结合，其腐烂率比对照组（CK）低46%，并在货架期结束时保持了果实品质。可溶性固形物含量（SSC）、硬度、失重和呼吸速率等理化性质的保持也证实了该处理的效果。此外，在货架期结束时，普鲁兰多糖涂膜与焦亚硫酸钾相结合，增加了总酚含量（37.59%）和类黄酮含量（9.28%）的积累，维持了较高的能荷（51.36%），并提高了超氧化物歧化酶（SOD）（6.27%）、过氧化物酶（POD）（62.50%）、过氧化氢酶（CAT）（84.62%）和苯丙氨酸解氨酶（PAL）（24.61%）的酶活性，同时启动了它们基因表达水平的上调。结果，果实的抗病性得到提高，软腐病的发生得到延迟。总体而言，本研究表明，使用基于普鲁兰多糖的活性涂膜结合焦亚硫酸钾处理可有效控制软腐病并延缓采后猕猴桃的衰老。
