Egg products are pasteurized to eliminate pathogens, mainly Salmonellae. Over the last few years, pasteurization methods have been modified to not only eliminate pathogens, but to increase the shelf life of refrigerated liquid egg products. The pasteurization process consists in heating the egg products to a pre-determined temperature for a pre-determined amount of time. The main problem is that egg products have a relatively low temperature at which they can be processed, otherwise the products would cook and/or loose their functional properties. This is the reason why it is impossible to process egg products at the conditions of time and temperature that would allow the production of an aseptic product. When evaluating pasteurization processes for egg products is important to determine the desired log reduction for the specific products. For example, a Log 4 reduction means a reduction in bacterial population of 99.99% and a Log 9 represents 99.9999999% reduction. The higher the temperature and the longer the holding time, the higher the Log reduction. It is also important to note that egg products are mainly used due to their excellent functional properties and that we have to remember that pasteurization affects these properties as well as their color and flavor. If we pasteurize products at higher temperatures to achieve a better shelf life, we may be reducing at the same time their “efficiency”. For example, a processing plant producing meringues using egg whites: Using raw egg whites as a reference, the plant will be able to produce 100 meringues per batch of egg whites. If this same processing plant uses pasteurized egg whites that were processed at the minimum time and temperature to eliminate salmonellae, it may produce 80 meringues. If now this same plant uses egg whites that were processed at the maximum time and temperature possible for shelf life purposes, it will process 50 meringues only. In this case the meringue plant will prefer to use raw egg whites to produce meringues.
