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International Agrophysics
publisher:Institute of Agrophysics
Polish Academy of Sciences
Lublin, Poland
ISSN: 0236-8722


vol. 10, nr. 2 (1996)

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Postharvest impact bruising of apple as related to the modulus of elasticity
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Y. Yuwana, F. Duprat
INRA, Laboratoire de Metliodes Physiques d'Etude, Site Agroparc, Domaine Saint Paul, F 84914 Avignon cedex 9, France

vol. 10 (1996), nr. 2, pp. 131-138
abstract The moduli of elasticity of fruit (E p and E 7) calculated from the maximum force reading (Fp) and from the average flesh force reading at 7 mm depth (F7) were used to predict bruise volume of apple during storage. The relationship between the measured bruised volume (MBV) and the predicted bruise volume based on E p (PBVp) was linear with coefficient of proportionality (Kp) of 4.61 and coefficient of correlation (R) of 0.928 while the relationship between the measured bruise volume (MBV) and the predicted bruise volume based on E 7 (PBVj) was linear with K7 of 231 and R of 0.903. Kp linearly correlated to the average of E p with R value of 0.974 and Ky linearly correlated to the average of E 7 with R value of 0.986. The values of E as well as K drastically decreased during two months storage time and were then relatively constant for longer storage time. Utilising E p Hertz's theory was underestimated 23.37 % while employing E-j it was overestimated 36.66 % in predicting postharvest bruising of Golden Delicious apple.
keywords apple, modulus of elasticity, predicted bruise volume, measured bruise volume