Comparative analysis of the composition and thermal properties of vegetable fats

Abstract

Goal. To establish the parameters of phase transitions of experimental vegetable fats by the method of differential scanning calorimetry (DSC) in correlation with their fatty acid and triacylglycerol composition. Methods. The parameters of phase transitions and mass fractions of solid triacylglycerols were studied by differential scanning calorimetry. The fatty acid and triacylglycerol composition of vegetable fats was determined using chromatographic analysis. Results. The fatty acid and triacylglycerol composition of the experimental samples of sunflower oil and palm olein was established. Of the fatty acid composition, sunflower oil and palm olein have 10 common fatty acids. Both experimental vegetable fats contain the highest content of palmitic, oleic and linoleic acids. But palm olein has a much higher content of palmitic and oleic acids, and linoleic — on the contrary, less than 6 times. The triacylglycerol composition of the experimental vegetable fats was analyzed, the main differences were established. Samples of vegetable fats by the method of differential scanning calorimetry were studied, as a result of which the temperature and thermal characteristics of phase transitions, mass fractions of solid triacylglycerols in the samples under conditions of different temperatures were established. If we compare the data of the fatty acid composition with the data of the temperature maxima of crystallization and melting, the increase in the content of palmitic acid by 1% increases the crystallization temperature by 0.52°C and the melting temperature by 0.57°C. Increasing the oleic acid content by 1% increases the crystallization temperature by 1.02°C and the melting point by 1.13°C. Conclusions. The obtained data make it possible to track the dependence of temperature behavior of vegetable fats on their composition and to quickly predict their functional properties during the selection of prescription components of different types of oil and fat products.