Effect of pullulan on the physicochemical properties of yoghurt

Abstract

The effects of pullulan ( PUL ) addition (0, 1.0 and 2.0% w/ v) on the physicochemical properties of yoghurts stored at 4 °C for 28 days were investigated. Fortification of the yoghurt with 1% PUL had a weakening effect on the gel network structure, leading to a decrease in initial viscosity and an extreme increase in syneresis, when compared to control. The addition of 2% PUL largely improved product stability by increasing gel firmness and adhesiveness, showing higher viscosity and consistency index values as well as displaying the lowest syneresis. Storage time increased yoghurt gel firmness and susceptibility to serum separation.