Role of Acetaldehyde Production in the Removal of Astringency from Persimmon Fruits under Various Modified Atmospheres

Astringency of persimmons was removed by enclosing the fruits in polyethylene bags under vacuum or by replacing air with N 2 or CO 2 . Acetaldehyde produced by the fruit under these conditions accumulated at different rates. The rate of the deastringency process was directly proportional to the level of acetaldehyde accumulation. Thus, the fruit held at 20°C in CO 2 was the first to lose its astringency, but showed internal browning after 1 wk. Fruits under vacuum or N 2 , where less volatiles accumulated, maintained their high quality and firmness for 2 wk at 20°C or 3 months at − 1°C. However, fruit held under vacuum began to show internal browning when acetaldehyde accumulated above a certain level.