Affects of spray-dying temperatures and carriers on antioxidant capacity and physical properties of instant mulberry powser
Abstract
The present study aimed to investigate the influences of inlet air temperatures and the induction of crystallization on mulberry powder during the process of spray-drying. Two independent variables including inlet air temperatures (120oC, 130oC, 140oC and 150oC, 160oC) and mixtures of carrier agents (Maltodextrin, Gum Arabic and Microcystalline Cellulose) were studied. The concentrations of microcrystalline cellulose added were 0, 0.5, 1, 2% (w/w). The powder was obtained from the Lab Plant SD06 spray dryer. Analyses of moisture content, bulk density, solubility, total phenolic contents (TPCs), total anthocyanin contents (TACs) and antioxidant activity (AC) were performed on the obtained powder. The study on temperatures showed that all of the analysed parameters were significantly affected with the shift in temperatures. At 160°C, the powder retained the highest value for TPC (38.32mg GAE/ g powder); however, the TACs and AC were relatively low compared to other temperatures. Meanwhile, at 140°C, the highest TAC value (468.80mg/ 100g powder) was obtained together with the relatively high TPC (35.69mg GAE/ g powder) and AC (39.43%), thus it was chosen to be the optimal condition for the study of carrier agents. The analysis of physiochemical of mulberry powder with the induction of MCC at 0, 0.5, 1, 1.5, 2% (w/w) was found to be significant. The addition of Microcystalline Cellulose in the process of spray-drying showed the remarkable decrease in term of moisture content, bulk density, solubility, TPCs, TACs and scavenging activity. The optimum conditions for the highest physiochemical properties were MD concentration of 21%, GA concentration of 8% and MCC content of 1%.
Keywords: mulberry, spray drying, antioxidant capacity, inlet temperatures, microcrystalline cellulose