2017 ASHS Annual Conference

Loss of crispness in apple fruit during storage reduces the fruit fresh sensation and consumer acceptance. Apple varieties with fruit that maintain crispness thus provide an opportunity for breeding cultivars with higher potential for longer-term consumer appeal. To effectively phenotype this trait, we studied an apple breeding population derived from a cross between Honeycrisp and MN1764, which segregates for crispness maintenance. Three types of instrumental measurements (puncture, snapping and mechanical-acoustic tests) and sensory evaluation were performed on fruit at harvest and after 8 weeks of cold storage. Overall, 22 genotypes from the population were characterized by 19 force and acoustic variables generated from the instrumental measurements. Principal component analysis (PCA) showed that force and acoustic variables were complemented in characterizing the instrumental properties of the apple population. The first two principal components accounted for 70% of the variance, with PC1 (49%) related mainly to force variables, and PC2 (21%) related to acoustic variables. In general, sensory crispness was correlated better with force variables than acoustic variables. The results suggested that loss of crispness may not be directly implied by a decrease of force and acoustic values.