The properties of karanda extract and chitosan coating incorporated with karanda (Carissa carandas Linn.) extract

Abstract

This research aims to study properties of karanda extract and chitosan coating incorporated with karanda extract. Karanda was extracted by distilled water at ratio between dried karanda and distilled water equal to 1:5, 1:6 and 1:7 (w/v). Then, karanda extract was mixed with chitosan coating at percentage of karanda extract equal to 1%, 3% and 5% (v/v). After measuring of antioxidation and antimicrobial activity of karanda extract and chitosan coating incorporated with karanda extract, the results presented that karanda extract had antioxidation activity and antimicrobial activity against E. coli. The karanda extract that extract by distilled water at the ratio between dried karanda and distilled water equal to 1:5 (w/v) showed the highest antioxidation and antimicrobial activity. Antioxidation and antimicrobial activity of the extract still active after using to prepare chitosan coating incorporated with karanda extract. Both activities increased when percentage of the karanda extract in the coating increased. For investigation of viscosity of the coating, viscosity of the coating decreased with increasing of percentage of the karanda extract in the coating. When coating the chitosan coating incorporated with karanda extract on tomato samples, the result showed that the consumers accept color, odor and appearance of the coated tomato samples more than that of tomato samples without coating. During storage interval, percentage of weight loss of coated tomato samples had lower than that of tomato samples without coating. However, weight loss values of coated tomato samples did not significantly depend on the percentage of karanda extract in the coating. After 15 days of storage period, the coated tomato samples still had the acceptable characteristics.