Batch variability and cultivar keeping quality of cucumber

A batch model is presented for the interpretation of batch behaviour in terms of current maturity, biological variation and maximal maturity towards keeping quality of cucumbers. The batch model describes the influence of one source of biological variation, here assumed to be variation in light conditions during the pre-harvest period, on the variation of precursor concentrations. The batch model consists of a kinetic part, describing the behaviour of the precursor for individuals, and a stochastic part, describing the precursor variation. The stochastic part is generic, but the kinetic part depends on the processes that determine keeping quality. The batch model is tested and validated using colour data of two sets of cucumber batches. Applying a previously developed cucumber colour model [Postharvest Biol. Technol. 26 (2002) 209], the precursor concentration determining the keeping quality at harvest was estimated. The amount of colour precursor at maximal maturity could be estimated in common for batches of the same cultivar and was defined as cultivar keeping quality. The batch model enables estimation of cultivar-specific information. It thereby takes advantage of the biological variation present in all biological batches, instead of treating it as a nuisance. © 2004 Elsevier B.V. All rights reserved.