Kou Runlei, Peng Mengfei, Zheng Jiaxuan, Hou Shuangdi, Ma Linyuan, Liu Xia
State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Food Nutrition and Safety, Ministry of Education of China, College of Food Science and Engineering, Tianjin University of Science & Technology, Tianjin 300457, China.
Key Laboratory of Agricultural Products Storage and Preservation, Ministry of Agriculture and Rural Affairs, Research Institute of Agricultural Products Preservation and Processing, Tianjin Academy of Agricultural Sciences, Tianjin 300384, China.
Foods. 2025 Jan 10;14(2):201. doi: 10.3390/foods14020201.
Lignification often occurs during low-temperature storage in loquat fruit, leading to increased firmness and lignin content, water loss, and changes in flavor. As induced stress factors, short-time high-oxygen pre-treatment (SHOP) can initiate resistant metabolism and regulate the physicochemical qualities during fresh fruit storage. However, the effect of SHOP on the lignification and quality of loquat has been reported less. In the present study, loquat fruit was immersed in oxygen concentrations of 70%, 80%, and 90% for 30 min before being stored at 4 ± 1 °C. The results showed that the 80% SHOP samples had lower lignin accumulation and firmness, showing reductions of 23.1% and 21.1% compared to the control at 50 days. These effects were associated with the inhibition of the activities of lignin synthesis-related enzymes, including phenylalanine ammonia-lyase (PAL), 4-coumarate-CoA ligase (4CL), cinnamyl alcohol dehydrogenase (CAD), and peroxidase (POD). Meanwhile, 80% SHOP improved the antioxidant enzyme system and maintained the structural integrity of the cells. Furthermore, SHOP retained the color and suppressed decay and weight loss and the decline in the soluble solids content (SSC) and titratable acidity (TA). As a convenient and cheap physical approach, SHOP is a promising technology for delaying lignification by regulating lignin synthesis in loquat storage.
枇杷果实低温贮藏过程中常发生木质化，导致果实硬度增加、木质素含量升高、水分流失和风味改变。作为诱导胁迫因子，短时高氧预处理（SHOP）可启动抗性代谢并调节鲜果贮藏期间的理化品质。然而，关于SHOP对枇杷木质化和品质影响的报道较少。在本研究中，枇杷果实在4±1℃贮藏前，分别置于氧气浓度为70%、80%和90%的环境中浸泡30分钟。结果表明，80% SHOP处理的样品木质素积累和硬度较低，在贮藏50天时，与对照相比分别降低了23.1%和21.1%。这些影响与木质素合成相关酶活性的抑制有关，包括苯丙氨酸解氨酶（PAL）、4-香豆酸辅酶A连接酶（4CL）、肉桂醇脱氢酶（CAD）和过氧化物酶（POD）。同时，80% SHOP处理改善了抗氧化酶系统并维持了细胞结构的完整性。此外，SHOP处理保持了果实颜色，抑制了腐烂和失重以及可溶性固形物含量（SSC）和可滴定酸度（TA）的下降。作为一种便捷且廉价的物理方法，SHOP是一种通过调节枇杷贮藏过程中木质素合成来延缓木质化的有前景的技术。
