Encapsulation of anthocyanins from purple yam extract (Dioscorea alata, L.) flour using maltodextrin-whey protein isolate

Abstract

Anthocyanins are antioxidant compounds that can act as anti-inflammatory, anti-viral, and prevention of diabetes. In Indonesia, many foods are rich in anthocyanin compounds, including purple yam tuber (Dioscorea alata L.). Anthocyanins are easily damaged by exposure to light changes in pH and temperature. Encapsulation can increase the nutritional value, color, shelf life, and bioavailability and stability of anthocyanin. The encapsulant such as maltodextrin and whey protein isolate were chosen because they were affordable and can protect the anthocyanin. Anthocyanin extract from purple yam flour were prepared to be incorporated in nanoencapsulation. Encapsulation were prepared with a ratio of maltodextrin and whey protein isolate = 1 : 3 (w/w) with anthocyanin extract of 5, 20 and 30%. Each formulas were dried by a spray drier. The results showed that the treatment using 30% anthocyanin extract resulted in the best nanoencapsulation. The encapsulation had anthocyanin content was 77.72 mg/100 g, total phenolic content was 510.07 mg GAE/100 g (db), antioxidant activity was 24.06 % RSA, color L∗ = 79.15, a ∗ = 5.58, b∗ = -0.39. Therefore, anthocyanin extract encapsulation can be produced successfully by this method.