College of Food Science and Technology, Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Product Processing and Safety, Guangdong Provincial Science and Technology Innovation Center for Subtropical Fruit and Vegetable Processing, Guangdong Province Engineering Laboratory for Marine Biological Products, Key Laboratory of Advanced Processing of Aquatic Product of Guangdong Higher Education Institution, Zhanjiang 524088, China.
Guangdong Provincial Key Laboratory of Applied Botany, Key Laboratory of Postharvest Handling of Fruits of Ministry of Agriculture and Rural Affairs, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.
Food Chem. 2024 Jan 1;430:137021. doi: 10.1016/j.foodchem.2023.137021. Epub 2023 Jul 25.
Pineapple as an important tropical fruit in the world is prone to internal browning (IB) caused by the oxidation of phenolic substances. To address the occurrence of IB, endogenous polyphenol oxidase (PPO) substrates were extracted, separated, and purified from pineapple fruit, and then four compounds were obtained and identified as catechin, epicatechin, chlorogenic acid and pyrocatechol. The contents of these substrates increased, reached the maximum value in the middle storage period, decreased gradually, and then maintained a relatively stable level by the end of storage. Meanwhile, pineapple PPO substrates were unstable in structure and susceptible to be degraded under the condition of light, high temperature (>40 °C), alkalinity (pH > 9) or metal ion (Ca, Cu, Fe, Pb and Zn). Additionally, the presences of O and HO increased the enzymatic oxidation of the pineapple PPO substrates, whereas CO, N, Vc (Vitamin C), l-cysteine, NaSO and NaSO inhibited this oxidation.
菠萝作为世界上重要的热带水果，易发生因酚类物质氧化导致的内褐变（IB）。为解决 IB 的发生，从菠萝果实中提取、分离和纯化了内源性多酚氧化酶（PPO）底物，然后得到并鉴定了 4 种化合物，分别为儿茶素、表儿茶素、绿原酸和邻苯二酚。这些底物的含量增加，在贮藏中期达到最大值，然后逐渐减少，最后在贮藏末期保持相对稳定的水平。同时，菠萝 PPO 底物结构不稳定，在光照、高温（>40°C）、碱性（pH>9）或金属离子（Ca、Cu、Fe、Pb 和 Zn）条件下容易降解。此外，O 和 HO 的存在增加了菠萝 PPO 底物的酶促氧化，而 CO、N、Vc（维生素 C）、l-半胱氨酸、NaSO 和 NaSO 抑制了这种氧化。
