Effect of heat treatments on the chemical composition and properties of sweetened condensed milk

The results of studies of the chemical composition and functional properties of sweetened condensed milk, resulting from heat treatment, are presented. The objects of research were sweetened condensed milk without heat treatment and subjected to thermal heating for 3 hours, sweetened condensed milk with boiled of industrial production. Objects were purchased in retail. The composition of sugars, free fatty acids and free amino acids was investigated by gas-liquid chromatography. Functional properties were investigated by sensory properties, viscosity on the analyzer EAK-1M and antioxidant activity by the FRAP method. Thermal heating of sweetened condensed milk resulted in a sugar-amine reaction with the formation of brown pigments as a result of the non-enzymatic browning reaction. There has been a change in color and texture of the product with an increase in its viscosity. The chemical composition of condensed milk has changed due to the inversion of sucrose and lactose. The products of hydrolysis entered sugar-amine reaction. The amount of free fatty acids and free amino acids increased slightly. In the process of heating, there was a change in antioxidant activity, which in the first two hours of heating decreased due to protein degradation. At the third hour, it began to increase due to the formation of melanoidins. The sweetened condensed milk boiled industrial production had antioxidant activity, but its values did not reach the values of condensed milk with sugar without heat treatment. Antioxidant properties of sweetened condensed milk and boiled condensed milk can be considered as a new factor for promotion in the consumer market.