**1.1 Definition of polyphenols and importance in food lipid quality improvement**

Polyphenols are a broad class of bioactive compounds found abundantly throughout different plant-based sources of nutrition, including fruits, vegetables, whole grains, legumes, and herbs. These substances have drawn a lot of interest because of possible health advantages and contribution to improving food lipid quality. The definition of polyphenols, significance in enhancing the quality of dietary lipids, and the interaction between moisture, drying temperature, and extraction method in polyphenol extraction from food sources will all be covered in this book chapter.
