건조방법에 따른 오크라의 영양성분 및 항산화활성 비교

Abstract

This study compares proximate analysis and antioxidant activity of hot-air dried and freeze-dried Abelomoschus esculentus. Based on the result of the proximate analysis, hot-air dried samples contained higher contents of carbohydrates and crude ash while freeze-dried samples were higher in crude fat and azoprotein. Both dried samples of Abelomoschus esculentus contained high content of Leucine, an essential amino acid, and Glutamic acid, a non-essential amino acid. Additionally, essential and non-essential amino acid contents in freeze-dried samples were higher. In hot-air dried samples, contents of organic acid was highest in Malic acid followed by Citric acid, Acetic acid, and Succinic acid in respective order while Malic acid contents was highest in freeze-dried samples followed by Acetic acid, Citric acid, and Succinic acid in respective order. The total amount of organic acids was higher in freeze-dried sample than in hot-air dried sample. 16 different types of fatty acids were found in the dried samples of Abelmoschus esculentus. Freeze-dried samples were indicated to have higher contents of fatty acid and minerals. The total amount of polyphenol was higher in freeze-dried sample while that of flavonoid was higher in hot-air dried sample. The ABTS+ assay IC50 value of Abelmoschus esculentus was higher in freeze-dried sample, and DPPH radical scavenging also indicated that freeze-dried sample has more effective antioxidant effect. Based on the analysis conducted on Reducing power and FRAP activation in dried samples of Abelmoschus esculentus, both were better in hot-air dried sample compared to freeze-dried ample. According to the result of comparative study on nutrient components and antioxidant activity in Abelmoschus esculentus depending on drying methods amino acids, organic acids, fatty acids, total polyphenol contents and values of ABTS+radical scavenging, DPPH radical scavenging, Reducing power, and FRAP were higher in freeze-dried okra compared to hot-air dried sample while mineral and flavonoid contents were higher in hot-air dried sample. Therefore it can be said that drying methods affects nutrient contents and antioxidant activity of Abelmoschus esculentus and freeze-drying methods results in less nutrient destruction and higher antioxidant activity compared to hot-drying methods.