摘要：Tomato paste is used for color and taste of food preparations. Besides taste qualities, tomato paste has a high nutritional value due to its highly assimilable carbohydrate, vitamin C, carotenoids and minerals. This paper aims to determine the effects of thermal treatment on bioactive components (vitamin C, .-carotene and lycopene) of tomato paste. Vitamin C was dosed with 2-6 diclorphenolindophenol method,, .-carotene by spectrophotometry and lycopene by spectrophotometric method too, using a water and alcohol solution in a 1:1 ratio. It was also followed, changing of the acidity , dry matter and the pH in tomato paste. In order to realize experiments, tomato paste with a 24% soluble dry matter containing, was maintained at 550C, 700C, 850C and 950C for 10 minutes. After heat treatment of tomato paste was brought to the initial weight so that evaporating water was completed. The results of experiments have shown that vitamin C decreased with increasing of the temperature, as well as .-carotene and lycopene amount increased with increasing temperature. Tomato acidity, expressed in citric acid decreases with increasing of the temperature and pH has varied little during the heat treatment.Loss not to register more than 50% of the total amount of provitamin A tomato should not be subjected to temperatures above 850CLoss not to register more than 50% of the total amount of vitamin C I recommend that tomato paste is not subjected to temperatures above 70
