This study evaluated the effects of CO2 and 1-MCP (1-methylcyclopropene) treatments on astringency (tannin index), flesh firmness and skin disorders on 'Rama Forte' persimmon. Fruit were treated with 1-MCP for 24 h right after harvest and/or with high CO2 (70% CO2 balanced with air) for 24 or 48 h, one day after harvest or after cold storage (CS). Fruit were stored in modified atmosphere for 45 days at 0ºC and then held at 23ºC for 9 days. Control fruit (untreated with neither 1-MCP nor CO2) softened in 3 days and lost about 50% of astringency in 6 days after CS. The high CO2 exposure enhanced the reduction of astringency. This CO2 effect was lesser on 1-MCP treated fruit, especially when high CO2 was applied after CS, for only 24 h. 1-MCP treatment inhibited fruit softening and the reduction of astringency, especially on fruit not treated with CO2. The softening of 1-MCP treated fruit was greater when the CO2 treatment was applied before CS. The combination of high CO2 and 1-MCP treatments reduced incidence of rots and translucent stains, but did not affect the development of dark 'groove like' skin disorders. The results indicate that it is possible to induce astringency loss without substantial loss of firmness of 'Rama Forte' persimmon by the combination of treatments with 1-MCP right after harvest and high CO2 after cold storage.
Diospyros kaki L.; texture; astringency; disorders
