EFFECT OF ADDITION OF MALTODEXTRIN ON TOTAL POLYPHENOL CONTENT (TPC), ANTIOXIDANT ACTIVITY AND COLOUR OF BLACK TEA

Abstract

During tea leave processing, maltodextrin is added illegally in order to improve the taste, color, to satisfy sensory needs of consumers and also to gain the weight after drying. Therefore this study was undertaken to determine the effect of maltodextrin on physiochemical properties of Ceylon black tea. Tea leave samples grown from of low, mid and up country were adulterated with 3, 6 and 10% maltodextrin solutions (w/v) and dried to obtain black tea. The non-adulterated samples were used as control. Each treatment has three replicates. The hot water extraction of black tea samples were analyzed for total polyphenol content (TPC), antioxidant activity and colour (Lab) by standard methods. The highest TPC (48.40 ± 0.15 mg GAE/ 100 ml) was recorded in control from up country sample and lowest TPC was observed in mid country sample with maltodextrin (10%) addition. The DPPH antioxidant concentration from low, mid and up country tea samples were varied in the range of 2.13 – 2.74 mg/ml, 2.39 – 3.78 mg/ml and 0.57 – 0.95 mg/ml, respectively. The results were revealed that TPC and antioxidant activity in low, mid and up country significantly decreased (p<0.05), however brightness was not significantly decreased, with increasing the maltodextrin concentration. This study will make awareness on effect of adulteration of phytochemicals in black tea among people.