Predicting the shelf-life of microbially-stabilised dairy products: what are the roles of stability studies, storage trials, ‘accelerated’ trials, and dairy science?

Much dairy science literature contains some consideration of dairy product stability in storage. Specific objectives of storage stability research are diverse, but the research is driven by a need to deliver consumer products that are acceptable and safe for a defined time – a shelf-life target. Unfortunately, it is not enough to control and measure storage stability; thus, dairy scientists frequently must also make predictions about shelf-lives. Predictions inform storage recommendations, best-before dates, and decisions to launch new products. This review considers work where dairy stability science guides predictions related to shelf-life for microbially-stabilised dairy products. Critical consideration is given to the reliability of predictions; especially when extrapolating from ‘accelerated’ and indirect methods. But even direct shelf-life methods are shown to be of limited accuracy due to numerous assumptions such as cut-off points. Making the distinction between stability science and shelf-life predictions is important, especially when communicating risks related to predictions.