Reducing the negative effects of chilling injury (CI) in tomatoes after harvest is fundamental to ensure good quality and to minimize losses. CI is a postharvest disorder associated with the generation of reactive oxygen species (ROS) in the fruit. Therefore, antioxidant accumulation can counteract ROS, alleviating CI symptoms. In this sense, a study of the scientists at University of Florida in Gainesville (USA) has confirmed that a brief hot-water (HW) immersion promotes the synthesis of antioxidants.
The scientists have found that HW treatment at 52°C for 5 min significantly reduced chilling‐associated decay, from 66.7% to 17.2% in breaker turning (BT) and from 55.8% to 9.8% in mature green (MG) ‘BHN‐602’ tomatoes stored at 5°C for 2 weeks and from 26.7% to 6.7% in BT tomatoes stored at 5°C for 1 week.
Furthermore, HW treatment significantly increased lycopene content by 17% in BT tomatoes stored at 5°C for 2 weeks, as well as ascorbic acid by 11%, lipophilic phenolics by 18% and total phenolics by 6.5% in BT tomatoes stored at 12.5°C for 1 week. Despite the increase of antioxidants, HW treatment did not enhance the sensory aromatic profile, color and antioxidant capacity. Interestingly, HW treatment reduced ripening time by 3 days in MG tomatoes stored at 5°C for 2 weeks or at 12.5°C for 1 week.
"Hot-water treatment applied to MG or BT ‘BHN‐602’ tomatoes can alleviate the development of some CI symptoms, particularly decay, possibly by increasing antioxidants that scavenge ROS", the scientists underline.
Source: Loayza Francisco E., Brecht Jeffrey K., Simonne Amarat H., Plotto Anne, Baldwin Elizabeth A., Bai Jinhe, Lon-Kan Elena, 'A brief hot-water treatment alleviates chilling injury symptoms in fresh tomatoes', 2021, Journal of the Science of Food and Agriculture, Vol. 101 (1), pag. 54-64.