45F-5 |
Edible coatings to extend shelf-life and enhance health benefit of fresh and frozen berries |
C. HAN1, Y. Zhao1, S. W. Leonard2, and M. G. Traber2. (1) Dept. of Food Science & Technology, Oregon State Univ., 100 Wiegand Hall, Corvallis, OR 97331-6602, (2) Linus Pauling Institute, Oregon State Univ., 571 Weniger Hall, Corvallis, OR 97331-6512 Strawberries and red raspberries have significant nutritional value and health benefits, but are highly perishable and have high physiological post harvest activities, which lead to a very short shelf-life, making the fresh market a challenge. Edible coatings have long been known to protect perishable fruits from deterioration. In addition, edible coating may carry nutraceuticals to further enhance the health benefit of the products. The objective of this study was to develop chitosan-based edible coatings containing calcium or vitamin E to prolong the shelf life and improve the health benefit of fresh and frozen strawberries and red raspberries. Chitosan based three coatings (chitosan, chitosan containing 5% calcium, or chitosan containing 0.2% vitamin E) were developed and applied on berries that were stored at 2.0ºC and 88% RH for 3 weeks or –23.0ºC for 2 months. Decay rate, color, firmness, weight and drip loss, titratable acidity, and calcium and vitamin E content of the berries were analyzed during cold and frozen storage. Coatings significantly reduced decay rate and weight loss, preserved the total acids of fresh berries during cold storage, and decreased the drip loss and improved texture quality of frozen berries. The shelf-life of fresh strawberries and raspberries were extended to 14 and 21 days, respectively based on their decay rate and physicochemical properties. Coatings also helped to maintain the integrity of frozen strawberries after thawing. In addition, about 5% DRI calcium and 22% DRI vitamin E were obtained in 200g strawberries, and 9% DRI calcium and 78% DRI vitamin E in 200g raspberries. This study proved the potentials to use edible coating as a carrier of nutraceuticals to extend shelf-life and enhance health benefit of fresh and frozen berries. The concepts of carrying nutraceuticals in edible coatings would meet the high market demands for functional foods.
Session 45F, Fruit & Vegetable Products: Fruits (Fresh)
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