不同干燥方法对番石榴果实品质及抗氧化活性的影响

为了比较热风干燥和真空冷冻干燥对不同品种番石榴果实品质及抗氧化活性的影响.采用热风干燥和真空冷冻干燥技术制备番石榴果实,以鲜果为对照,探究不同干燥方式对6种番石榴的可溶性固形物、总酸、总糖、抗坏血酸、单宁、总酚、类黄酮等含量及抗氧化活性的影响.结果 发现,与鲜果相比,干燥得到的6个品种番石榴的可溶性固形物、总糖、总酸、...

The Effects of Drying Methods on Fruit Quality and Antioxidant Activity of Guava

To compare the effects of hot-air drying and vacuum-freeze drying on fruit quality and antioxidant activity of different guava varieties, this study took fresh fruits as the control treatment, prepared the guava fruits by hot-air drying and vacuum-freeze drying, and explored the effects of different drying methods on the content of soluble solids, total acids, total sugar, ascorbic acid, tannin, total phenols, total flavonoids and the antioxidant activities of six guava varieties. The results showed that, compared with the fresh samples, the soluble solids, total sugar, total acid, tannin, ascorbic acid and total flavonoid content and the total antioxidant capacity of the six guava varieties after drying treatment all decreased significantly, while the total phenol content showed an upward trend. Hot-air drying was conducive to retaining the total flavonoid and tannin content of the guava fruits, while vacuum-freeze drying could retain the soluble solids, total sugar, total acid, total phenol and ascorbic acid content of the fruits, as well as the antioxidant activities. Among the six guava varieties, after hot-air drying and vacuum-freeze drying, the soluble solids, total sugar and total acid content of ‘Jindouxiang’ guava did not decrease significantly compared with those of fresh fruit. In addition, its total phenol and total flavonoid content and the total antioxidant capacity were higher than those of other guava varieties. After drying, the total phenol content of ‘Jindouxiang’ increased by about 2.5 times, while the flavonoid content could retain more than 50% of that of the fresh fruit, and the total antioxidant capacity retention rate could reach 60.98%. In conclusion, drying process could obtain more phenolic substances from guava fruits, vacuum-freeze drying is more conducive to the retention of phenolic substances and ascorbic acid, while hot-air drying is conducive to the retention of total flavonoids. Considering the retention of active ingredients and variety characteristics, vacuum-freeze drying could be used as a better processing method for large-scale production of dried guava products, and the guava variety ‘Jindouxiang’ could be the first choice.