ACOUSTIC AND SENSORY MEASUREMENTS OF DIFFERENT RIPENESS OF APPLES

Abstract

In a previous work, the impact of harvest date on apple quality by considering the correlations between acoustic measurements (stiffness coefficient) and sensory evaluation by a trained panel has been studied. The relationships with other destructive measurements were studied as well. Three different stages of ripeness were chosen. For each variety, apples were harvested three weeks before, on the optimal date itself (determined by an expert) and three weeks after. All of these apples were tested two weeks after harvesting. The later the apples were harvested, the lower the stiffness, touch resistance and crunchiness were. In contrast, sweetness and odour intensity increased. Significant positive correlations were observed between stiffness and touch resistance and crunchiness. In the current work, the same methodology of studying different levels of ripeness was used, completed by the impact of storage on apple quality. Acoustic, sensory and instrumental textural measurements were taken from each apple. So correlations were studied using individual fruit data and not only using averages as previously done. The high correlations between acoustic and textural measurements found earlier were confirmed. Stiffness seemed to be a good non-destructive parameter for measuring apple texture. The correlation between sensory and instrumental measurements was also studied, comparing results based on both individual fruit data and the averaged data.