Cultivar and maturity effect on dyeing properties of persimmon fruit juice.

摘要

Immature fruits of 5 local and 3 commercial persimmon cultivars were harvested from late-June to late-August at 10-day intervals to study the coloration pattern by tannin treatment using persimmon fruit juice as influenced by cultivars and fruit maturity. Colour emergence on cotton fabrics and subsequent colour changes under sunlight were also evaluated. The dyeing properties of the fruit juice were influenced by the time of fruit harvest. The hue values of cotton fabrics increased until mid-July then decreased. The lightness and saturation values gradually increased from late-June to late-August. The colour of the fabrics dyed with the fruit juice from local cultivars was darker than that from the commercial cultivars, probably due to higher tannin concentrations of the former than the latter. The amount of tannic acid was positively related to the colour of the fabrics dyed. The brightness and saturation values of the fabrics increased when the fruits were harvested earlier since they contained more soluble tannin. However, the differences in dyeing properties could not be ascribed solely to the differences in tannin concentrations because the same juice preparations exhibited different dyeing properties when dyed in June and in August..