In master's thesis we evaluated quality parameters before and after storage of bell peppers, tomato and lettuce. Samples investigated were of different geographical origin (Morroco, Turkey, Spain, Italy, Greece, Slovenia) and were provided in 4 different shoping centers in Slovenia. Analyses carried out included chemical parameters: total phenols, antioxidant potential, ascorbic acid, carotenoids, chlorophyll, nitrates and nitrites, ammonium and sensory analyses. For the storage experiment peppers and tomato were stored in a dark room at 10-12 °C, while lettuce was stored at 1,2 °C, all commodities for ten days. Content of total phenols, antioxidant activity and ascorbic acid was the highest in bell pepper, while the content of chlorophyll a and b and nitrates, nitrites and ammonium was the highest in lettuce. Regarding geographical origin vegetables from Morroco, Turkey and Italy contained more nitrates and nitrites as well as ammonium, while the Morroco and Turkey samples contained less bioactive compounds compared to other production locations. The most influential parameters to diferentiate between geographical locations were: ascorbic acid, ammonium, nitrates and nitrites, total phenols, antioxidant potential, neoxanthin and β-carotene. In storage experiment pepper retained more bioactive compounds and also showed the highest sensory quality compared to tomato or lettuce. In lettuce the content of most bioactive compounds as well as sensory quality decreased during storage – faster as compared to bell pepper or tomato investigated. Loss of sensory quality is attributed mostly to appearance (wilting, weight loss), appearance of nontipical smell and aroma as well as the growth of moulds.
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