30C-4 |
Will blade tenderization decrease iridescence in cooked beef semitendinosus muscle? |
E. OBUZ, Food Science Graduate Program, Kansas State University, 216 Weber Hall, Manhattan, KS 66506 and D. H. Kropf, Department of Animal Sciences and Industry, Kansas State University, 247 Weber Hall, Manhattan, KS 66506. Color, an important characteristic of any meat, is the indication of freshness, appropriate storage temperature, adequate processing, and wholesomeness. Deviations from proper meat color may decrease the value of meat products and result in consumer rejection. Iridescence, a rainbow-like or multi-colored appearance, is a microstructural color problem caused by optic diffraction or multiple thin film interference. Iridescence might originate from the birefringence of collagen or from myofibrils. Consumers may confuse iridescence colors with microbial discoloration, resulting in the rejection of the product by the consumers, which is very costly to meat industry. Blade tenderization improves meat tenderness through mechanical muscle disruption. Since iridescence may be a structural phenomenon, blade tenderization might reduce or eliminate iridescence. The objective of this study was to observe the effects of blade tenderization on iridescence of cooked beef semitendinosus muscle. Ten beef semitendinosus muscles were vacuum packaged and stored at 3°C. Each muscle was divided into three sections and blade tenderization (control, one time, or two times) was applied. Blade tenderized muscles were cooked to 63°C and held for 1 min in a forced-air convection oven at 163°C. Cooking loss was evaluated. Cooked muscles were chilled overnight at 3°C and sliced by a sharp knife. The sliced samples were vacuum packaged in PE/nylon/PE film. Panelists (n=19) evaluated iridescence intensity on a five-point scale (0 being no iridescence, 5 being very strong) and extent of iridescence (0 being no iridescence, 5 is 81-100% affected area). Blade tenderization decreased (p<0.05) iridescence intensity from 2.37 to 2.02 (5-point scale) and extent of iridescence from 2.18 to 1.83. Cooking loss increased (30.4% control, 32.6% one pass, 33.75% two passes) with blade tenderization (p<0.05). Blade tenderization decreased iridescence slightly by disrupting muscle structure. Blade tenderization coupled with other methods such as altered cooking temperatures might reduce or solve iridescence problem.
Session 30C, Muscle Foods: Tenderness, Quality, Processing, Marination, Oxidation, and Shelf-Life
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