EXPLORING TOMATOES DEHYDRATION TECHNOLOGIES: EFFECTS ON NUTRITIONAL AND FUNCTIONAL QUALITY

Tomatoes (Lycopersicum esculentum) are important sources of vitamin A, C, folic acid, potassium, as well as fiber and healthy fats, constituents that can ensure a healthy diet. The rich nutritional composition of tomatoes includes phenolics and carotenoids that position them as a functional food. Drying is an essential method for avoiding microbial spoilage of food. Dehydration of tomatoes leads not only to biological stability but also to a large variety of food available all year round, without requiring particular storage conditions such as refrigeration. Dried tomatoes contain nutrients and antioxidants such as lycopene and beta-carotene, which give them their red color. The processing methods are critical for the quality of the dried tomatoes. This study investigated the influence of pretreatment (i.e., ultrasonication), hot air drying, and vacuum drying on the quality attributes of two cherry tomatoes, namely Aurora and Rutgers. Ultrasonic-hot air drying led to an increase of the dry matter (d.m.) content from 33.87 ± 0.08% to 79.37 ± 0.21% (Aurora variety), respectively from 34.32 ± 0.17% to 78.69 ± 0.24% (Rutgers variety). Comparing the drying methods, ultrasonic-vacuum air drying can be recommended to dehydrate tomato samples to avoid a high degradation of lycopene. Applying this method, the amount of lycopene ranged from 9.71 ± 0.16 mg/100g d.m. (Aurora variety) and 8.69 ± 0.12 mg/100g d.m. (Rutgers variety) in fresh tomatoes to 8.50 ± 0.20 mg/100g d.m. (Aurora variety) and 7.75 ± 0.10 mg/100g d.m. (Rutgers variety) In dehydrated products. Vacuum drying proved to be a suitable technique for obtaining dehydrated tomatoes with good quality, a further detailed assessment of other changes in sensorial and chemical terms being needed.