| Summary: | 碩士 === 國立臺灣海洋大學 === 食品科學系 === 104 === Fresh-cut fruits are becoming more attractive to consumers who are aware that the healthy eating habits is important. However, it is difficult to preserve fresh-cut fruits for long-term storage. In that case, edible coatings and films are the proper way to maintain the quality of fresh fruits and vegetables, which can extend their shelf-life. Furthermore, using fish skin as the extraction of gelatin to produce biopolymer edible films, which may reduce the waste disposal issue of the fish-processing industry. In this study, fresh-cut apples were treated with chitosan (1.5%), gelatin (4%), chitosan-gelatin complex (1.5% chitosan and 2% gelatin), or water (control), and were stored at 5°C and 22°C for 12 days, was investigated. During the storage, the weight loss of all treated apples were increasing since day 4, which loss by 2.36%. All of the samples were decayed when they kept at 22℃ for 4 days, except for those were coated by chitosan. Control sample and fresh-cut apple treated with chitosan-gelatin maintain their lightness values than others kept at 5℃ for 12 days. On the other hand, the sample coated with chitosan had significantly (p < 0.05) lower L values at 22°C compared to the fruit at 5°C at end of the storage. In addition, hue angle results for all the samples were similar to the result of the L values. The browning index values of all samples increased rapidly at day 4, and then leveled off. By the end of the 12 days cold storage, chitosan coated samples kept the highest firmness values throughout storage. There was no significant difference among the result of pH and total soluble solids in all the apple cubes during storage. The titratable acidity of the chitosan coated apple cubes stored at 22°C decreased more than others from 0.26% to 0.14% at the end of the 12 days. The fruits with chitosan and chitosan-gelatin coated showed a slower increase in ascorbic acid in cold storage, which suggested that chitosan and chitosan-gelatin coatings slowed down the senescence. In addition, chitosan and chitosan-gelatin coatings had the lowest population of the total aerobic bacteria, yeast and mold and coliform. There was no significant difference among the treatments for the overall quality scores of the samples stored at 5℃ for 12 days. Base on the above results, chitosan-gelatin not only maintains the firmness of the fruit but also improves the quality during cold storage, and which also suggests that chitosan-gelatin is suitable as an edible coating to be used in commercial fresh-cut fruits application for prolonging the shelf-life of the fresh-cut apples.
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