Green tea marinades can reduce formaldehyde of pan-fried pork via Mannich reaction mechanism

Foods containing proteins or unsaturated fatty acids can generate toxic formaldehyde upon exposure to high thermal. Polyphenol-fortified food has been proved to be has less heat-induced toxic aldehydes formation (including formaldehyde), however, the chemical mechanism underlie such effect has not been fully revealed. In the present research, whether Mannich reaction mechanism is responsible for natural polyphenols's inhibition on formaldehyde production on cooking meat was explored. It is validated that green tea marination can suppress the accumulation of formaldehyde of pan-fried porks. By using HPLC, LC-ESI-MS and LC-ESI-HRMS analysis, members of catechins from tea polyphenols were found has high activity for Mannich addition. Besides, a serial of polyphenol-formaldehyde-amino acid three-component adducts were found in the extract of green tea marinated pork. Herein, we proposed firstly that tea polyphenols' inhibitory effect on formaldehyde was accounted for (at least in part) the formation of Mannich adducts.