Abstract

UTILIZATION OF CONCENTRATED AND LACTOSE HYDROLYZED WHEY IN THE PREPARATION OF BUNS

Somashekara Reddy P. V.*, Surendra Nath B. and Priyatam Reddy K.

Abstract

Whey is a major byproduct of the dairy industry generated during the manufacture of cheese, paneer, chhana, chakka and casein. It is highly nutritious, containing about 40-50% of total solids, 80-90% lactose, 20% proteins, 70% minerals and almost all the water soluble vitamins of whole milk from which it is obtained. Disposal of whey as practiced by the dairies not only causes the loss of these valuable nutrients but also incurs cost for the treatment of whey. Utilization of whey in the preparation of food products often requires concentration to increase the total solids (TS) level, which results in an increased lactose level in the products. In the present study, process was optimized to hydrolyze lactose in concentrated paneer whey and utilize the same for the preparation of buns, an important bakery product. Colorimetric methods for estimation of lactose and thereby evaluation of degree of hydrolysis (DH) of lactose in concentrated paneer whey were standardized. Lactose in concentrated paneer whey could be hydrolyzed up to ~60% in 60 min using lactozyme under optimal conditions of hydrolysis. Concentrated paneer whey (up to 20%TS) could be utilized in the preparation of buns with desirable quality. Trials showed that replacement of maida with 25% wheat flour yielded buns with quality comparable to that of control product. Due to hydrolysis of lactose and release of sweeter monosaccharides, sucrose required in the bun preparation could be reduced from 10 to 7%. Utilization of concentrated lactose hydrolyzed whey (20% TS and 60% DH) and wheat flour (25% replacement of maida) required necessary modifications for achieving optimal proofing and baking. The yield of buns calculated on the basis mass balance of ingredients was 73.5 and 76.86% for control product prepared using water and experimental buns prepared using concentrated, lactose hydrolyzed paneer whey respectively. Sensory and textural quality of the experimental buns was observed to be better than that of the control product. The experimental buns had 28.90, 9.95, 12.30, 1.72, 47.43 and 1.42% respectively of moisture, fat, protein, lactose, total carbohydrates and ash. The corresponding values for the control were 30.46, 9.64, 11.81, 0.75, 46.9 and 1.3% respectively. Experimental and control samples packed in LDPE pouches had a shelf life of 4 days at 300C. This investigation showed that concentrated (20% TS) and lactose hydrolyzed (≈60% DH) paneer whey and wheat flour (25% replacement of maida) could be successfully utilized for the production of buns.

Keywords: Whey, Lactose hydrolysis, Buns, concentration of lactose.