HEAT TREATMENT EFFECTS ON THE BIOCHEMICAL AND NUTRITIONAL CONTENT OF DOUBLE CONCENTRATE TOMATO PASTE

This paper deals with the valuation of the effect of heat treatment on nutrients contents of tomato cans. Increasing heat temperatures reduce significantly Brix values at 110°C. Lane-Eynon method reveals that all forms of major sugar in tomato paste are reducing ones. ACP statistical analysis demonstrates that decreasing of protein values was highly correlated with the sugar values variations along with decreasing in pH values. Such a decrease seems to be more important at 110°C than at 100°C. Student t test identified a significant difference between viscosity at 100°C and 110°C, and being correlated to proteins content rather than of sugar. Antioxidants (lycopene and tocopherol) preserve paste consistency and are more stables than ascorbic acid.