50-11 |
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S. GAWBORISUT and J. L. Silva. Dept. of Food Science, Nutrition and Health Promotion, Mississippi State Univ., 110 Herzer Bldg., Mailstop 9805, Mississippi State, MS 39762-9805 Low-dose irradiation improves safety and shelf-life of various species of fish including catfish, the major aquaculture species produced in the United States. However, the impact of the process on eating quality of catfish fillets has not been investigated. The effect of low-dose, X-ray irradiation (0, 2, and 3 kGy) on physicochemical characteristics of raw catfish fillets (water holding capacity: WHC, texture, color, pH, and oxidation, TBA), physicochemical characteristics of baked catfish fillets (cooking loss, texture, color, and TBA), and sensorial quality of raw and baked catfish fillets (appearance, texture, odor, and overall acceptability) were studied over the experimental period of 24 d. Doses of 2 and 3 kGy increased pH and TBA of raw catfish fillets and produced minor effects on color of raw and baked catfish fillets, but had no effect on WHC, cooking loss, texture of raw and baked catfish fillets, and TBA of bakecatfish fillets. Although irradiation increased TBA of raw catfish fillets, the values were much lower than the objectionable level of 1 mg/100 g sample, thereby not being of practical importance. Irradiation of raw catfish samples resulted in lower sensory ratings. Excessive superficial exudates, irradiation-induced off-odors (burnt, warm-over cook, and unusual sweet smell), caused reduction in appearance, odor, and overall acceptability scores for raw irradiated catfish fillets. However, upon cooking, irradiated catfish fillets regained their appreciable appearance scores. Moreover, the objectionable odors produced during irradiation were partially dissipated and were masked by desirable thermal-induced odors leading to higher odor and overall acceptability scores. Texture of either raw or baked catfish fillets perceived by panelists was not influenced by irradiation. Low-level X-ray irradiation did not affect physicochemical characteristics and eating quality of catfish fillets.
Session 50, Aquatic Food Products: General
2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana |