Impact of Climate Variables Before Harvest on Content and Response of Carotenoids, Tocopherols and Vitamin C to Postharvest Thermal Processing of Tomato

This study was conducted to investigate how the climate variables of cultivation affect the response of phytonutrients in tomato to thermal processing of juice and their stability. Cultivation in a location with a higher temperature, longer sunshine, and lower precipitation yielded tomato with higher content and stability of carotenoids, mainly lycopene, which lost 39% and 55% of its initial concentration because of cold-break (CBE) and hot-break (HBE) extraction, respectively. The lycopene loss caused by CBE and HBE was 70% and 59%, respectively in tomato cultivated in the location with higher precipitation, lower temperature, and shorter sunshine period. Seasonal variation in climate manifested its effect in increasing the total carotenoid content, mainly isomers and oxidized derivatives of lycopene and β-carotene, particularly in tomato produced in the location of higher precipitation and low temperature. Similar Pattern of change and response was observed for β-Carotene, lutein, phytoene, and phytofluene and total and individual tocopherols as well. As concerns vitamin C, the abiotic factors had no significant effect on its content in tomato fruits, but its stability during processing, especially with hot-break extraction, was significantly affected by climate variables of the cultivation location (P<0.01-0-001). The content and stability of phytonutrients in the pomace, the by-product of tomato juice processing, were also evaluated.