MICROENCAPSULATION OF ROSELLE (HIBISCUS SABDARIFFA L.) THROUGH SPRAY DRYING

Roselle calyces are known for their rich nutritional content, bioactive compounds and therapeutic properties.However, these calyces have a limited seasonal availability and are highly perishable.As a result, processing of roselle calyces through spray drying is crucial in increasing the availability of the product during the off-season.Thus, an attempt was made to optimise the processing variables viz., inlet temperature (170, 180 and 190 C) and maltodextrin concentration (5, 10 and 15%).The results of different parameters varied moisture content 5.74-6.14%,water activity 0.37-0.50,swelling capacity 13.33-12.46ml/g, water absorption capacity 9.45-8.51ml/g, anthocyanin content 716.26-697.29 mg/100g, total phenols 39.06-38.79mg GAE/100g and antioxidant activity 92.22-87.31%.In conclusion, the high-quality spray dried roselle powder can be obtained at inlet temperature of 190C and maltodextrin concentration 15 per cent resulted in minimum moisture content, water activity, swelling capacity and water absorption capacity that could be stable for the storage.