This is kinda gross:

In a new paper published online Oct. 8 in the journal Cell, Breslin and colleagues propose a theory of food pairings that explains for the first time how astringent and fatty foods oppose one another to create a balanced “mouthfeel.”

Because fat is oily, eating it lubricates the mouth, making it feel slick or even slimy, Breslin said. Meanwhile, astringents, chemical compounds such as the tannins in wine and green tea, make the mouth feel dry and rough. They do this by chemically binding with lubricant proteins present in saliva, causing the proteins to clump together and solidify, and leaving the surface of the tongue and gums without their usual coating of lubrication. [Tip of the Tongue: The 7 (Other) Flavors Humans May Taste]

We don’t like slimy, but we don’t like puckered up, either. “We want our mouth to be lubricated but not overly lubricated,” Breslin told LiveScience. “In our study, we show that astringents reduce the lubricants in the mouth during a fatty meal and return balance.”

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