Shelf life estimation of brown pan bread:: A consumer approach

In this study three different approaches-acceptability limit, failure cut-off point methodology, and survival analysis-to estimate the sensory shelf life of brown pan bread elaborated with different enzymes using consumer data were compared. The study was carried out in Spain and Uruguay independently, where four batches of bread were produced, with the same base formulation, one without enzyme, the others with the addition of maltogenic amylase, xylanase, and a mixture of both. The results showed that for Uruguayan consumers the mixture of enzymes provided better results in extending shelf life than the addition of amylase alone. For the Spanish consumers only the addition of amylase provided the desired results, and for consumers of both countries the use of xylanase did not extend the shelf life of bread. Among the methodologies used for the estimation, survival analysis provided the most adequate predictions considering consumer rejection of the product. Hedonic scales do not always reflect consumer behaviour when deciding whether to accept or reject a certain product for its consumption. (C) 2005 Elsevier Ltd. All rights reserved.