The use of Design of Experiment and sensory analysis as tools for the evaluation of production methods for milk

Milk and milk-based products are heat treated at the dairy to eradicate pathogenic microorganisms and to prolong the product's shelf life. There are differences of opinion about which process is the most gentle towards milk and milk-based products when the product is heat treated at high temperatures. Before making an investment decision on new production equipment for milk and milk-based products, Aria Foods was given the opportunity to compare two different production methods. It was decided to use Design of Experiment (DoE), as this is an effective method for obtaining maximum information with a minimum of experiments. It's a method to determine which factors significantly influence the measured variables. The effects of the two production methods for milk were investigated. Variable factors comprised the processes (A and B), fat content of the milk and temperature. This was a full factorial design with three centre points for each process. The responses were different sensory attributes. The results showed that there were no significant differences regarding sensory analysis for the production methods. This facilitated an investment decision based on other criteria such as price, maintenance costs, service agreement, etc. (C) 2004 Elsevier B.V. All rights reserved.