Microwave heating and conduction heating pork belly: Influence of heat transfer modes on volatile compounds and aroma attributes

This work was conducted to compare the differences in odor attributes and the formation causes of pork belly cooked by different heating modes and the feasibility of achieving convenient and delicious cooking of stir-fried pork cuisines by modifying the heat transfer mode of the microwave. The effects of traditional pan-heating (TH), microwave heating (MH), and microwave combined with conduction heating (MH + CH) on sensory aroma attributes, aroma profile, free fatty acids, and volatile compounds of pork belly were investigated. The results showed that the pork belly heated by TH had the lowest total amount of stable volatile compounds (1695.41 μg/kg) and contents of free fatty acids (751.44 mg/100g), but the balanced distribution and the rich contents of volatile compounds derived from thermal processing resulted in the better aroma quality of pork belly. In contrast, although the pork belly cooked by MH had higher free fatty acids contents (1215.32 mg/100g) and the highest volatile compounds (5410.56 μg/kg), due to the cell destruction effect and the molecular movement acceleration of microwave, the contents of volatile compounds derived from spices were too high, leading to the disharmony of aroma characteristics. However, the pork belly cooked with MH + CH not only promoted the production of free fatty acids (1434.23 mg/100g), but also increased the generation and retention of pork characteristic aroma by changing the heating modes. Compared with MH, it enhanced the uniformity of aroma distribution and improved the overall aroma similarity to TH.