45F-11 |
Microstructural, physicochemical and sensorial effects on ´Rocha´ pears under controlled atmosphere storage |
A. C. GALVIS-SANCHEZ1, S. C. Fonseca, and F. X. Malcata. (1) Escola Superior de Biotecnologia, Universidade Catolica Portuguesa, Rua Dr. Antonio Bernardino Almeida, Porto, 4200-072, Portugal Refrigerated and controlled atmosphere (CA) storage is an important postharvest technology aimed at preservation of quality of fresh fruits, which consequently adds market value to said horticultural product. This technology may be combined with the great storage potential of ´Rocha´ pears, a cultivar with rather appealing sensory characteristics but which is still insufficiently explored. In this work, the influence of storage under low O2 and various (high) CO2 levels on the microstructural, as well as on sensorial and physicochemical quality parameters of ´Rocha´ pears were assessed. Storage atmospheres of 2 %(v/v) O2, 2 %(v/v) O2 + 0.5 %(v/v) CO2 and 2 %(v/v) O2 + 5 %(v/v) CO2 in all cases (balance N2), as well as air as control were duly tested. After 4 mo of storage, sensorial attributes (viz. juiciness, sweetness, yellowing and firmness), color parameters, instrumental firmness and juiciness, polyphenoloxidase (PPO) activity, phenolic and vitamin C contents of pears were evaluated throughout time of exposure to the open air at room temperature (1, 6 and 9 d). Several micrographs of pear pulp using light and scanning electron microscopy were produced. An experienced panel analysed the microstructural images in terms of specific descriptors. Empirical models were developed that describe the influence of O2 and CO2 volumetric concentrations of the CA, as well as time at room temperature on the aforementioned quality parameters of ´Rocha´ pear. Relationships were thus obtained between instrumental, sensorial and microstrutural parameters of ´Rocha´ pears. Statistical analyses of the experimental data using ANOVA indicated that storage atmospheres had a significant effect on those quality parameters. The beneficial effects of CA over air storage were made apparent in terms of sensorial attributes, color parameters, PPO activity and vitamin C content. Quality retention of ´Rocha´ pears was significantly improved with storage under 2 %(v/v) O2 + 0.5 %(v/v) CO2.
Session 45F, Fruit & Vegetable Products: Fruits (Fresh)
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