91B-22 |
Effects of edible coatings containing antibrowning agents on respiration rate and color in minimally processed apples |
J. Y. LEE, The Graduate School of Biotechnology, Korea University, 1, 5-ka, Anam-dong, Sungbuk-ku, Seoul, 136-701, South Korea, H. J. Park, Graduate School of Biotechnology, Korea University, 1, 5-ka, Anam-dong, Sungbuk-ku, Seoul, 136-701, South Korea, and C. Y. Lee, Department of Food Science & Technology, Cornell University, Geneva, NY 14456. The color of products such as apple slices is an important quality index. To extend the shelf-life of minimally processed products, the respiration rate must be controlled. Application of antibrowning agents and edible coatings can minimize increased respiration and cut-surface browning caused by minimal processing. Carrageenan or whey protein concentrate(WPC) coatings provide a good oxygen barrier and are useful as a carrier of antibrowning agent. Therefore, the combination of antibrowning agents and edible coatings was used for minimally processed products to reduce respiration rate and inhibit surface browning. The objective was to evaluate the effect of the carrageenan and WPC coatings with a combination of antibrowning agents on respiration rate and color change in minimally processed apples. Cut apples were treated in test solutions for 2 min and drained. Dipping solutions of ascorbic acid, citric acid, oxalic acid and combination were applied on cut apples. Edible coatings were made from carrageenan and WPC, and combined with or non antibrowning agents. Color was measured for 24h at room temperature. Respiration rate was measured at room temperature for 3h after cold storage for 1 d. Combinations of three browning inhibitors were effective on color retention of cut apples, however, these treatments increased respiration rate of cut apples. Respiration rate showed a decrease by 10% and 20% in carrageenan coated and WPC coated samples, respectively. WPC coatings containing ascorbic acid-oxalic acid mixture showed effective antibrowning activity and induced lower respiration rate than others. Carrageenan coatings containing same mixture didn't exhibit reduction of respiration rate. These results suggest that WPC coatings on cut apples can be beneficial because WPC coated apples respired lower than sample treated with ascorbic acid-oxalic acid mixture alone. Application of this coating formulation on minimally processed product can maintain fresh food quality and extend their shelf-life in food market.
Session 91B, Food Chemistry: Physicochemical properties
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