Encapsulation of Betalains Extracted from Red Dragon Fruit Peels by Freeze-drying using Microcrystalline Cellulose and Dragon Fruit Peel Pectin as Wall Materials
Encapsulation of Betalains Extracted from Red Dragon Fruit Peels by Freeze-drying using Microcrystalline Cellulose and Dragon Fruit Peel Pectin as Wall Materials
Tran U.P.N., Dang-Bao T., Le P.T.K., Huynh U.D.H., Nguyen T.T.H., Le T.M., 2022, Encapsulation of Betalains Extracted from Red Dragon Fruit Peels by Freeze-drying using Microcrystalline Cellulose and Dragon Fruit Peel Pectin as Wall Materials, Chemical Engineering Transactions, 97, 31-36.
Red dragon fruit (Hylocereus polyrhizus) has good potential to be processed into many kinds of food products. The processing of dragon fruit always discarded large volumes of peel waste. The residual peel of red dragon fruit is rich of betalains and pectin, which are alternative food additive sources. This study utilized red dragon fruit peels to produce betalains and pectin. Because betalain pigment is unstable in processing and storage, it was encapsulated in carbohydrate matrices of pectin (recovered from red dragon fruit peel - DFP) and microcrystalline cellulose (MCC). An appropriate freeze-drying procedure was employed to form pigment powder with 60 to 93 % encapsulation yield. The stability of the encapsulated betalains was investigated under various conditions such as pH, water activity, temperatures, and light after 30-day storage. Betalains encapsulated in a combination of MCC and DFP showed stability improvement compared to non-encapsulated betalains, which is potentially beneficial in food processing.
