Effects of Heating Temperatures on the Physicochemical Characteristics and Flavor of Lard Diacylglycerols

Our aim was to study the effects of three different heating temperatures (95, 120 and 145 ℃ ) on the physicochemical properties and flavor of lard diacylglycerols (DAG). The Fourier transform infrared (FTIR) spectrum, melting and crystallization characteristics, crystal form, rheological properties, thermogravimetric properties, fatty acid composition and volatile components of DAG were determined. The results showed that the crystal form of DAG changed from β’- to β-type with increasing temperature. Infrared spectroscopy showed that heating changed the functional group distribution of DAG. The rheological and thermogravimetric analysis showed that the viscosity increased while the thermal stability decreased. The content of volatile flavor substances such as aldehydes and alcohols gradually increased with increasing temperature, and the content of unsaturated fatty acids increased first and then decreased. Different heating temperatures affected the physicochemical properties and flavor of DAG. The most suitable temperature for processing lard DAG was 120 ℃ .