Influence of postharvest temperatures on physicochemical quality of tomatoes (Lycopersicon esculentum Mill.)

Author: Dragan Žnidarčič ^1*, Dean Ban ², Milan Oplanić ², Lutvija Karić ³ and Tomaž Požrl ¹

Received 22 September 2009, accepted 29 December 2009.

Abstract

Tomato fruits (cv. Belle) were harvested at the middle-red ripe stage and exposed at 5^oC and 10^oC for up to 28 days. Weight loss percentage was faster for fruits held at 10^oC compared to 5^oC. While the weight lost during storage at 10^oC was 18.7%, fruits at 5^oC over the same period showed a 9.6% loss. There were only slight changes in soluble solids and titratable acids content during the storage period studied. Although soluble solids increased slightly over the storage period, there were no significant differences between the two temperatures. The titratable acidity, expressed as citric acid, tended to be lower at 5^oC, with a significant difference observed only on Day 14 of storage. Total reduction of initial vitamin C content was 3.5 mg/100 g (at the 5^oC) and 2.5 mg/100 g (at the 10^oC). The results showed that lower temperature did not significantly reduce vitamin C content in comparison with higher temperature, with the exception on Day 7 of storage. At both temperatures and at every stage of storage time pericarp firmness decreased as storage time increased. The decrease in firmness was delayed by the lower temperature. The colour development (value a) of skin increased with increasing storage duration at both temperatures, but there were no differences among temperatures.

Key words: Lycopersicon esculentum Mill., temperature, storage, physicochemical quality.