Physicochemical characterization of spray-dried horseradish root juice encapsulated within maltodextrin/alginate

Abstract

Spray-drying is one of the widely used techniques to extend the shelf-life and easier handling of vegetable juices. However, the high temperatures in the spray-drying chamber may cause the degradation of the bioactive components of the juices. Also, the enzyme activity and sugar content of fresh juices can lead to difficulties in drying and resulting in powders with unfavorable physicochemical properties. To overcome these problems, juices can be encapsulated within various biopolymers. Carbohydrates, maltodextrin, and alginate were used as carriers for the spray-drying encapsulation of bioactive components of various plant juices and extracts. To our knowledge, there are no reported studies on the encapsulation of horseradish root juice within these carriers. Therefore, this study aimed to investigate the influence of the maltodextrin/alginate carrier mixture on the physicochemical properties of the horseradish root juice preserved by the spray-drying encapsulation technique. Root juice powder without a carrier (C, control sample) and maltodextrin/alginate encapsulates of root juice (MD/AL) were prepared by spray-drying. The powders were analyzed using standard analytical methods to determine the moisture content, water activity, hygroscopicity, oil holding capacity, bulk, and tapped density. Moisture content, water activity, and hygroscopicity were lower in MD/AL (7.8%, 0.28, 22.9 g/100 g) than in C (10.2%, 0.32, 24.4 g/100 g). MD/AL had a higher oil holding capacity (1.4 g oil/g) compared to C (1.1 g oil/g). The values for bulk and tapped density were for MD/AL 0.5 and 0.7 g/cm3 and C 0.6 and 0.7 g/cm3, respectively. Finally, the encapsulation of horseradish root juice in maltodextrin/alginate resulted in powders with significantly better physicochemical properties than spray-dried horseradish root juice without carrier. Based on this study, it can be concluded that the encapsulation process has great potential for the preservation of vegetable juices and provides many perspectives for further research and application in food products.