SHELF-LIFE PREDICTION OF READY-TO-EAT FOOD PRODUCTS VIA SURVIVAL ANALYSIS

Sensory analysis is one of the main quality indices in shelf-life and storage studies for foods, especially for products which are microbiologically stable such as heat stable meals. In this study, survival analysis methodology was used to estimate the shelf-life of eight types of vegetable meals packed in retortable plastic containers by using results obtained from consumers when asked if they would accept or reject samples with different storage times. A hedonic scale approach was also considered in order to measure the progressive loss of overall quality characteristics. Fifty con¬sumers were recruited and six sampling times were planned to obtain the evaluation data. For the analysis of the overall quality score, repeated measure analysis was used, whereas for shelf-life estimation, accelerated failure time models were employed. Results showed that the effect of storage time on the overall quality evaluations along the first three sampling times was significant, and some products seemed to receive lower quality values than others at the end of the follow-up period. The shelf-life estimated for the total of products using probability of product failure of 50% was 32.9 months (CI_95% 21.1-43.0), and differences in shelf-life among the eight products were also found.