Publications

A floor cover to improve temperature distribution and quality preservation in maritime refrigerated container transport of grapes : GreenCHAINge WP1 - Table Grapes

Lukasse, Leo; Mensink, Manon; Wissink, Edo

Summary

Like many other fruits, table grapes depend on accurate temperature management during transport in maritime refrigerated containers. Ideally the temperature inside the container is equal to set point in every location in the container. Unfortunately door-end temperatures are always higher due to poor air flow distribution. In climate chamber tests Lukasse & Staal (2016a and 2016b) investigated the effect of covering sections of the container’s T-bar floor. The best T-bar floor cover found in that study was a trapezoid-shape floor cover. The aim of this study is to assess the effect of that trapezoid-shape T-bar floor cover on temperature and fruit quality in commercial reefer container transports of grapes. A field experiment was done in a commercial container shipment of six standard 40 ft. HC reefer containers travelling from South Africa to The Netherlands taking 24 days. The three test containers contained a T-bar floor cover. The three reference containers did not contain the T-bar floor cover. All other parameters were, to the extent possible, the same for all containers. In 31 locations air temperature between the fruit was logged at an interval of 10 min. with an accuracy of approx. ± 0.1 °C. 15 Trays, evenly distributed in a vertical plane on the container’s longitudinal centre line, were weighed at origin and at destination. At destination the fruit quality of these 15 trays was analysed. A clear positive effect on temperature was observed. The floor cover reduces the average difference between warmest and coldest temperature in the trays by approx. 30%. An effect on grape quality could not be assessed.