Survival analysis, consumer perception and physico-chemical analysis of low fat UHT milk stored for different time periods

Abstract

Survival analysis based on consumers' acceptance or rejection of milk of different storage ages, was used to validate the shelf-life of low fat ultra-high temperature treated (UHT) milk in high density polyethylene bottles, as previously determined by a multivariate accelerated shelf-life test (MASLT). UHT milk between 120 and 290 d of storage were evaluated. Based on 50% of consumers rejecting the product, the shelf-life was estimated to be 214 d, validating the shelf-life of 211 d estimated by the MASLT. In addition, consumers completed check-all-that-apply attribute questions and rated the acceptability of the milk. The consumers noted positive sensory attributes more frequently in fresher milk samples with an increase in negative attributes with storage. Along with this, hedonic scores for the milk decreased and physicochemical and enzymatic reactions associated with the deterioration of UHT milk increased with storage.