A general procedure for predicting the remaining shelf life of nectarines and peaches for virtualization of the value chain

Abstract

Decision-making along the supply chain requires accurate estimates of the remaining shelf life (RSHL) depending upon not only the initial storage conditions and duration but also aspects such as the variety or condition of the fruit at harvest. Offering ready-to-eat fruit on at the retail level, is a frequent marketing strategy in which management of shelf life is mandatory. The most widespread models, so-called generic shelf life models for estimating the RSHL gather the actual temperature series and the optimal storage temperature while assuming standard values for other parameters such Q10 or the reference shelf life. In this work, a general mathematical procedure, and corresponding algorithm are proposed to adjust the parameters of the generic RSHL model referring to several varieties of peaches and nectarines. Postharvest protocols are simulated to obtain ready-to-eat fruit for recently bred varieties. To this aim, temperature was recorded continuously throughout the postharvest protocol, while instrumental and sensory evaluations were taken at the end of each stage of the protocol. Outputs of a principal component analysis based on instrumental data allowed to i) identify the instrumental variables most relevant to sensory evaluation and corresponding evolution under shelf life conditions and ii) define a multidimensional estimator of shelf life. The particular values of this multidimensional estimator together with the temperature series are the basis to solve the equation that lead to specific values of Q10 and reference shelf life for each variety in the study. The average reference shelf life of peaches is bounded to 24 d, 30 % shorter (10 d less) than the average shelf life of nectarines. The Q10 values are bounded between 1.5 and 2.8, highlighting the varietal effects. Generally, Q10 values for peaches are indicative of a higher susceptibility to the breakage of the cold chain compared to nectarines.