The purpose of master's thesis was to determine the content of vitamin C, pigments, total phenols, nitrates and nitrites, ammonium, antioxidant potential (AOP) and sensory analysis of fresh and storage lettuce, tomatoes and bell peppers produced according to six different cultivation methods (organic, biodynamic, conventional, integrated, hydroponic and control). The same analyses were also done on the same crop species aquired from comercial pruducers. Results show that cultivation method affects the content of ammonia in tomatoes. Higher levels contained samples from shops and conventional production. Significantly higher content of ascorbic acid, total phenols and pigments were determined in tomatoes after storage. Higher levels of ascorbic acid were found in tomatoes and peppers from hydroponic cultivation. More ascorbic acids were found in tomatoes cultivars 'Buran' and 'Tadim'. Cultivation method had no effect on AOP of vegetables, also we did not find differences in the AOP between varieties. Red coloured peppers contained more ascorbic acid, had higher AOP and higher content of total phenols than yellow coloured peppers. The cultivation method did not affect the content of total carotenoids in vegetables. The differences were found only between individual carotenoids. The sensory properties of vegetables decreased during storage time. Significant differences were found between conventionally grown tomatoes, which had a better taste and aroma compared to organically grown. We also found the differences between the sensory properties of individual varieties of tomatoes.
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