Fouling of Milk on Heat Transfer Surface with and without the Addition of Bacillus stearothermophilus – A Laboratory Study

Jinah Yoo, University of Auckland
Xiao Dong Chen, University of Auckland; Corresponding author
Bipan Bansal, University of Auckland

Abstract

Fouling of heat transfer surfaces during milk processing is a major problem for dairy industry. In the current work, the nature and extent of milk fouling with and without the addition of Bacillus stearothermophilus in the feed solutions have been studied. A fouling detection system based on electric conductivity measurements has been used. The coresponding thermal resistance of the deposit layer has also been worked out. The fouling deposits have been analysed visually as well as with a scanning electron microscope (SEM). The results show significant variation in the fouling patterns with and without the large presence of bacteria in the flowing medium.