1986 Volume 33 Issue 3 Pages 176-180
Japanese persimmon cv. Sanja were harvested and the compositions and other attributes were measured at regular intervals throughout the growing season. Color development in peel was closely related with the color value "a" measured with the color difference meter. The color value "a" increased remarkably after October 10th. The color index by the color chart was correlated with the color value "a" and was a useful indicator for maturation. Soluble tannin content in the fruit was between 3 and 4%, till September 20th and then decreased gradually. Soluble tannin contents in the fruit harvested on November 10th (ordinary harvest maturity) and 20th were approximately 1.5 and 1.0%, respectively. Fructose and glucose were relatively constant untill October 1st, whereas sucrose markedly increased throughout the experiments. The concentrations of these sugars were 3.3, 3.9 and 4.4% on November 10th. It was not reliable to estimate the sugar content from the reflactive index value. Though the flesh firmness was relatively constant untill October 1st, it decreased rapidly thereafter along with the loss of the pectic substances. Moisture, crude fiber and total ascorbic acid contents were tend to decrease, while no significant changes were observed in crude protein, ash and titratable acidity.
