Correlation between instrumental quality attributes and consumers' sensory evaluation in refrigerated-stored 'Campbell Early' and 'Kyoho' grape.

Relationship between instrumental quality attributes and consumers’ acceptance in ‘Campbell Early’ and ‘Kyoho’ grapes were analyzed to indicate an appropriate instrumental attribute reflecting the changes in overall taste during 4-month refrigerated storage. Relationship between instrumental measurements and sensory ratings were studied through correlation study using 32-or 64-paired data set obtained at one-month intervals during storage. Soluble solids concentration (SSC) was not significantly correlated with sweetness and overall taste. Correlation between titratable acidity (TA) and overall taste was significantly negative in ‘Campbell Early’, while positive in early-harvested ‘Kyoho’ grape. Highly positive correlation was found between flesh firmness and overall taste in early- and late-harvested ‘Campbell Early’ and early-harvested ‘Kyoho’ grape suggesting that flesh firmness can be used as an indicator reflecting the consumer acceptance for grapes during storage. Minimum levels of flesh firmness for acceptable eating quality were 0.44, 0.30, and 0.20 N for early-, late-harvested ‘Campbell Early’ and early-harvested ‘Kyoho’ grapes, respectively. As related to consumer’s eating habits, SSC: TA ratio of free juice seemed to be an appropriate quality factor indicating consumer acceptance for ‘Campbell Early’ grape but not for ‘Kyoho’ grape.