Tyramine

Tyramine ( TY-rə-meen) (also spelled tyramin), also known under several other names, is a naturally occurring trace amine derived from the amino acid tyrosine. Tyramine acts as a catecholamine releasing agent. Notably, it is unable to cross the blood-brain barrier, resulting in only non-psychoactive peripheral sympathomimetic effects following ingestion. A hypertensive crisis can result, however, from ingestion of tyramine-rich foods in conjunction with the use of monoamine oxidase inhibitors (MAOIs).

Occurrence

Tyramine occurs widely in plants and animals, and is metabolized by various enzymes, including monoamine oxidases. In foods, it often is produced by the decarboxylation of tyrosine during fermentation or decay. Foods that are fermented, cured, pickled, aged, or spoiled have high amounts of tyramine. Tyramine levels go up when foods are at room temperature or go past their freshness date.

Specific foods containing considerable amounts of tyramine include:

Strong or aged cheeses: cheddar, Swiss, Parmesan, Stilton, Gorgonzola or blue cheeses, Camembert, feta, Muenster

Meats that are cured, smoked, or processed: such as salami, pepperoni, dry sausages, hot dogs, bologna, bacon, corned beef, pickled or smoked fish, caviar, aged chicken livers, soups or gravies made from meat extract

Pickled or fermented foods: sauerkraut, kimchi, tofu (especially stinky tofu), pickles, miso soup, bean curd, tempeh, sourdough breads

Condiments: soy, shrimp, fish, miso, teriyaki, and bouillon-based sauces

Drinks: beer (especially tap or home-brewed), vermouth, red wine, sherry, liqueurs

Beans, vegetables, and fruits: fermented or pickled vegetables, overripe fruits

Chocolate

Scientists more and more consider tyramine in food as an aspect of safety. They propose projects of regulations aimed to enact control of biogenic amines in food by various strategies, including usage of proper fermentation starters, or preventing their decarboxylase activity.