MECHANICAL ASSESSMENT OF TEXTURE OF SWEET CHERRIES - EFFECTS OF FREEZING

In this study the authors analysed which objective mechanical parameters, obtained by means of penetration, shear and Kramer shear cell tests, best explain the results obtained through sensorial assessment of the texture of six varieties of sweet cherry, and the changes undergone therein during the freezing process. The results suggest that the mechanical parameters selected should be independent of sample weight and volume, and that sample preparation should be as non-destructive as possible. All the mechanical test parameters used in this work discriminate between varieties, but not all are useful for assessing the effect of freezing. The maximal force displayed on the shear-test curve is the parameter that best reflects the firmness of the product whether fresh or frozen. The slope of the penetration-test curve best reflects the variations in turgidity of the fruit as a consequence of freezing.