Development of Potentially Functional Drink from Skimmed Milk Enriched with Red or Black Variety Rice Bran

Abstract

Rice bran is a good source of antioxidants such as polyphenol compounds that are potentially formulated in skimmed milk drink. The objectives of this research were to develop potentially functional drink from skimmed milk enriched with red or black variety rice bran and to evaluate their physical, chemical and sensory qualities. The milk drinks were formulated with skimmed milk (95%) and sucrose (5%) as fixed formula. Considering the result of preliminary research, the addition of red or black variety rice bran at amount of 4, 6, 8% (w/w) and carboxy methyl cellulose (CMC) at amount of 0, 0.05, 0.1% (w/w) were based on fixed formula and water addition in ratio 4:1 (w/w) of water weight and total weight of skimmed milk powder, sucrose, rice bran, and CMC. The milk drink formula was selected based on total phenolic content (TPC), total anthocyanin content (TAC) and its antioxidant activities using DPPH and FRAP assay. Two selected formulas were characterized in terms of physical properties (viscosity and colour), chemical properties (pH, total soluble solid, and proximate), and sensory evaluation by rating hedonic. Red and black variety rice bran had high TPC with amount 512.19±43.91 and 1247.56±196.34 mg GAE/100 g, TAC with amount 1.94±0.19 and 40.69±4.21 mg C-3-G/100 g, respectively. Red and black variety rice bran also showed antioxidant activity based on DPPH assay (106.68±13.49 and 209.93±19.75 mmol Trolox/100 g, respectively) and FRAP assay (8.04±0.39 and 14.66±0.56 mmol FeSO4/100 g, respectively). The milk drink enriched with red variety rice bran, the highest content of TPC (33.83±1.00 mg GAE/100 mL), TAC (1.86±0.32 mg C-3-G/L), and antioxidant activities of DPPH (83.38±1.37 mmol Trolox/100 mL) and FRAP (0.43±0.01 mmol FeSO4/100 mL) by addition of 8% red variety rice bran and 0.05% CMC. The milk drink enriched with 8% black variety rice bran and 0.1% CMC showed the highest values in TPC (39.61±0.11 mg GAE/100 mL), DPPH (196.22±3.77 mmol Trolox/100 mL), FRAP (0.63±0.07 mmol FeSO4/ 100 mL) and TAC (5.53±0.03 mg C-3-G/L). Furthermore, the proximate analysis showed that the selected drinks had low fat content and high fiber content. Both milk drinks also were moderately liked on overall liking attribute. Based on its TPC, TAC and antioxidant activities, these milk drinks enriched with black and red variety rice bran are potentially developed as functional drinks.