No abstract

The relationship between compressive forces, tensile forces and sensory perception of apple and pear texture was evaluated over two harvest years. A trained panel assessed the sensory attribute of apple and pear samples. Compressive forces were determined using a Guss Fruit Texture analyzer and Sinclair iQ™. Tensile determinations were obtained using a unique method employing both tensile and compression elastic modulus of the fruit tissue. Results showed that crispness, hardness and fracturability were significantly correlated (r = 0.80–0.90). Sinclair iQ™ System and Guss Fruit Texture measurements on apple (r = 0.78–0.83) and pears (r = 0.83) showed a significant correlation with sensory results for hardness. Tensile determinations predicted crispness in apples (r = 0.88) and pears (r = 0.85). A combination method of compressive and tensile determinations may offer the most accurate prediction of textural properties of apples and pears. PRACTICAL APPLICATIONS Apple and pear firmness is a primary measure of fresh quality. With apples and pears being such an important commodity in Washington State and firmness playing such an important role in fruit quality, more knowledge about tissue mechanics and its correlation with human perception is important for further development of the apple and pear industry. In response to the need to develop an instrumental determination of texture with a strong correlation to sensory evaluation, a new methodology was developed whereby the tensile properties of apples and pears were measured.

The sensory quality of Gala apples stored for up to 4 months in delayed controlled atmosphere (CA), regular atmosphere (RA), and a combination of sequential CA and RA storage (CR) was evaluated. Sensory analysis included difference and acceptance testing. Firmness, soluble solids and titratable acidity contents, and volatile flavor profiles were measured analytically. Acceptability decreased with storage time. Apples stored in RA were more acceptable than apples stored in CA or CR; the differences between storage treatment were not significant after 4 months of storage. Firmness decreased with storage time, but was not affected by storage treatment. Soluble solids and titratable acidity contents were not affected by storage treatment or time. Storage treatment, storage time, and lot had a signif cant effect on the volatile flavor profiles. CA storage and extended storage contributed to decreases in the content of volatile flavor compounds.