Microencapsulation of blackberry pulp extract (Rubus fruticosus) cv.TUPY by spray drying

The blackberry (Rubus fruticosus) cv. Tupy is a fruit rich in anthocyanins and phenolic compounds, which has high antioxidant activity. However, its short shelf life, due to its fragility and high postharvest respiration rate, consists of an enormous challenge for the agri-food industries. Application of microencapsulation by spray drying is a technique to maintain or increase the stability of the blackberry pulp bioactive compounds and to prolong its shelf life. The objective of this research work was to obtain pulp blackberry in powder microencapsulated with mixture of starch arrowroot and gum arabic (1:1) by spray drying process. A central composite rotatable design (CCRD), with 11 experimental runs, was performed to evaluate the effects of input air temperature (100 150 °C) and encapsulating agent concentration (1:0.5 1:2 proportion of blackberry pulp solids: encapsulant), having as responses: drying process yield, moisture content, water activity, hygroscopicity, ascorbic acid content, color, anthocyanins content and antioxidant capacity. The increased proportion of blackberry pulp solids: encapsulant resulted in increased yield drying process. This variable had a significant influence on decrease of anthocyanins content of the blackberry pulp powders. The independent variables showed significant effects on the respective responses: drying process yield, water activity, hygroscopicity, color, ascorbic acid content and anthocyanins content.