MANUFACTURE OF FERMENTED NUTRACEUTICAL MILK PRODUCTS HIGHLY IN SOLUBLE DIETARY FIBER

This study was undertaken to evaluate the feasibility of using soluble dietary fiber and probiotic bacteria to produce nutraceutical fermented cow milk. Fresh cow milk without addition served as a control (T1). β- glucan (T2) or glucomannan (T3) was added to fresh cow milk (30mg/L). All treatments were heated at 85°C /10min, cooled to 45°C. Each treatment inoculated with yoghurt starter culture (Yo) or Lb. acidophilus (A) or Lb. helveticus (H) at a level of 3% and incubated at 42°C. After fermentation all samples were cooled and keep at 4°C for 1 day, yoghurt mixed with fermented milk contains Lb. acidophilus or/ and Lb. helveticus as well as Lb. acidophilus fermented milk mixed with Lb. helveticus at ratio 1:1 and 1:1:1. Titratable acidity, microbiological analysis and sensory evaluation were determined in all samples. Incubation time was different among all treatments to reach the titratable acidity 0.7%, where it was lower in control than other treatments. Titratable acidity of fermented milk was affected by adding soluble dietary fiber, where fermented milk with β- glucan (T2) or glucomannan (T3) had lower acidity than fermented milk without dietary fiber (T1). Types of starter cultures had no significant effect on the titratable acidity of fermented milk. Addition of β- glucan or glucomannan decreased total lactic acid bacterial counts (TLAB) as compared with control. Treatments of Yo, A and H resulted in significant lower TLAB count than mixed treatments. Spore forming counts in T2 and T3 treatments were significantly lower than control. Addition of β- glucan or glucomannan improved the body and texture, compared to the control, particularly, Yo+H and Yo+A+H.