Microbial reduction and energy analysis of milk pasteurization

Abstract

It is well documented that milk can harbour a number of different bacteria. Bacterial contamination of raw milk generally occurs from three main areas; from inside the udder (mastitic infections), outside the udder (surface contamination eg soil, faeces), and from the surface of equipment used for milk handling and storage (milking machine etc) (Wallace, 2009). In order to remove the risk of bacteria existing in commercial milk certain steps must be taken. Hygiene is of course extremely important and a reduction in microbial numbers can be achieved by improving milking procedures. However to insure the removal of pathogenic bacteria from milk pasteurization must be carried out. This investigation will research the pathogenic bacteria involved with milk, a brief history of pasteurization, the methods of pasteurization used globally and the problems that may arise in milk processing. An examination on the ability of pasteurization to reduce total colony counts will be carried out comparing different temperature and time pairings. The energy required to carry out these processes will also be looked at. In an ever developing market it is important to reduce energy consumption and improve efficiency.