Unveiling how ventilated packaging design and cold chain scenarios affect the cooling kinetics and fruit quality for each single citrus fruit in an entire pallet

Abstract

• We target the impact of 3 ventilated packaging designs and 3 cold chain scenarios. • We quantify cooling kinetics and fruit quality evolution for over 3000 fruit in a pallet. • The Supervent package provides the overall best performance. • The ambient loading scenario, so loading fruit warm in the container, is a promising alternative. • We identify which specific box in a pallet has the longest shelf life. Optimizing fresh fruit supply chains is essential to reduce food losses and the associated environmental impact, as large amounts of energy and natural resources are embodied in these lost products. Proper refrigeration of these perishable items is essential here, and the used ventilated packaging design and cold chain scenario play a key role. This study pioneers in unveiling how package design, package position on a pallet, package stacking pattern and cold chain scenarios affect the cooling kinetics and fruit quality evolution for every single fruit of the thousands of fruit inside a pallet. This enables us to identify fruit quality heterogeneities on a pallet level, where previous studies typically focused on an order of magnitude less fruit. For this purpose, our recently developed virtual cold chain methodology is applied to these large ensembles of fruit, which relies on computational fluid dynamics simulations. Of the three evaluated packaging designs for citrus fruit, the Supervent package outperforms the Standard and Opentop packaging by providing the overall fastest and most uniform cooling. Supervent’s performance is attributed to the alignment of ventilation pathways through the lateral vent holes. The performance of the Standard package is very similar, apart from the inefficient cooling at lower speeds. The Opentop packaging exhibits lengthy and non-uniform citrus fruit cooling, due to the unequal distribution of the vent openings on its long and short sides, and near the top surface. This unequal distribution fosters the creation of preferential pathways and faster cooling of the top layer of fruit in each box. Concerning the cold chain scenarios, forced-airflow precooling is the fastest to bring down the temperature after harvest. The promising scenario “ambient loading”, where citrus fruit are loaded at ambient temperatures in the container, proves to be a worthy alternative. We could also show that stacking the pallet in a mechanically more stable way negatively affects the cooling heterogeneity. Finally, our methodology enables us to identify, for a certain cold chain, which box on the pallet the customer should choose to have the longest shelf life, or which box the retailer should sell first.