Spray drying of grape juice from hybrid cv. Brs Violeta: microencapsulation of anthocyanins using Protein/maltodextrin blends as drying aids.

Grape juice contains high amounts of anthocyanins, with great potential for substituting synthetic food dyes. Carrier agents used in spray drying entraps anthocyanins, allowing their preservation. This work appraised whey protein/ maltodextrin (WM) and soy protein/maltodextrin (SM) blends as alternative carriers for spray drying of grape juice and encapsulation of anthocyanins. The effects of carrier agent concentration (CAC) and ratio protein/carrier agent (R) on grape juice powder properties were evaluated. The grape juice powders presented good solubility, low water content and high anthocyanin retention. WM blends resulted in higher yields and higher anthocyanin retention (from 77.9 to 94%) than SM blends, whereas SM blends leaded to higher encapsulation efficiency (>97%). Increasing CAC and R resulted in brighter powders, but reconstituted juices presented color parameters similar to those of fresh juice. WM and SM were suitable for encapsulating anthocyanins of grape juice, resulting in powders with potential applications in food industry. PRACTICAL APPLICATIONS The grape cultivar BRS violeta contains high levels of anthocyanins and is an alternative to produce antioxidant-rich and highly colored grape juice. Spray drying is applied for producing powdered grape juice with high anthocyanin content. In this technique, the addition of whey and soy proteins blended with maltodextrin as carrier agents avoid problems such as stickiness, which is negative to process yield and product quality. Moreover, the use of carrier agents in spray drying promotes the microencapsulation of bioactive compounds, allowing their protection and preservation during processing and storage. The grape juice powder from cv. BRS Violeta can be applied in the food industry as a potential substitute for synthetic food dyes, in addition to being a promising additive for incorporating anthocyanins into functional foods.