Due to the great diffusion of frozen foods and frozen convenience foods, a rapid procedure for shelf-life estimation appears a very interesting research topic. In fact, shelf-life determination for frozen food can be a time spending process, because of the long duration of shelf-life at the low storage temperatures. The development of deterioration reactions in frozen food is hardly predictable due to the occurrence of phase transitions of crystallising components (i.e. water, sugar, lipids). While a great number of results is available on the mechanisms of lipid oxidation, few researches have been performed on the influence of the physical state of lipids on the development of rancidity in food. In the following pages, the Authors have described the fundamental aspects of lipid crystallisation and the relationships between physical state and stability of lipids at sub-zero temperatures.
