Kiwi-hu-suk is a traditional Chinese medicine used for treating kidney problems. It is also known as ‘Hayward’ kiwifruit. The treatment has a number of advantages, including being able to delay the ripening process. The treatment also has some beneficial effects on the quality and phenolic content of the fruit.
Effects of 1-MCP on quality of kiwifruit
The effects of 1-MCP on the quality of kiwifruit are unknown, but the ethylene inhibitor has been found to prolong fruit shelf life by inhibiting the activity of ethylene. It prevents ripening and helps maintain fruit firmness, even when kiwifruits are exposed to low CO2 and high O2 levels. Hence, 1-MCP has been found to be an effective postharvest management tool for kiwifruit.
The effects of 1-MCP on kiwifruit were evaluated in two studies. In the first experiment, kiwifruit were exposed to 1-MCP at a concentration of 1 mL/L for 30 days, 60 days, and 90 days. The fruit were then evaluated for its quality during storage.
1-MCP inhibits ethylene production and reduces respiration. In addition, it inhibits the activity of cell wall degradation enzymes, which are associated with hard core texture. However, more research is needed to determine the exact mechanism by which 1-MCP works.
Effects of 1-MCP on phenolic content of kiwifruit
In this study, 1-MCP was applied to kiwifruit before and after storage. The treated kiwifruit showed lower SSC than control fruit at 0degC and 10degC, and increased slightly at 20degC and at 13 days of storage. At the same time, untreated kiwifruit showed a significantly higher SSC than treated fruit.
The ‘Hongyang’ kiwifruit, which contains high levels of vitamins and nutrients and is very tasty, is particularly susceptible to postharvest decay at late stages. To investigate whether 1-MCP could reduce the decay of kiwifruit and improve their disease resistance, researchers applied it to kiwifruit stored at 0degC for six months. The 1-MCP treatment improved total flavonoid content and superoxide dismutase activity.
1-MCP affected the expression of two ethylene biosynthesis genes, AcACS and AcACO, which are critical for ripening kiwifruit. In addition, 1-MCP downregulated the expression of AcLOX, a gene involved in ripening. This decreased ethylene production, delayed softening and weight loss, and suppressed the activity of ACS and ACO.