Non-destructive Measurement of Strawberry Fruit Firmness (Part 1)

Relationship between Strawberry Fruit Firmness and the Cell Wall Constituent Pectin

Abstract

The firmness of strawberry fruit greatly affects such factors as operability, transportability and quality maintenance. In this study, as part of our search for non-destructive measurement method of strawberry fruit firmness, we investigated the relationship between fruit firmness and pectin, a constituent of plant cell walls. Fruit state was categorized according to color, e.g., unripe, half ripe, ripe, and fruit firmness was measured. Pectin fractions were then extracted and determined quantitatively for 67 fruits. The relationship between strawberry fruit firmness and content of alcohol insoluble solid (AIS) and hydrochloric acid soluble pectin (HSP) was indicated by correlation coefficients of 0.814 and 0.875 respectively. Given these results, strawberry fruit firmness appears to be strongly correlated with AIS and HSP content.