Garlic Compounds. Half-Life of Garlic "Hotness" after Crushing or Chopping.
Updated: Dec 9, 2022
You just cut, chopped, and smashed a few cloves of Garlic. Immediately, a powerful chemical reaction begins. Crushing or chopping garlic releases an enzyme called alliinase that catalyzes the formation of allicin. Crushing or chopping garlic releases an enzyme called alliinase that catalyzes the formation of allicin from S-allyl-L-cysteine sulfoxide (Allin). Allicin rapidly breaks down to form a variety of organosulfur compounds. The formation of thiosulfate is very fast and has been found to be complete in about a minute after crushing garlic. The strong garlic flavor that is produced does not last very long. That is one good reason not to buy "Minced Garlic" in a jar.
In many cultures, garlic has been used for culinary purposes for centuries, likely because Garlic is a particularly rich source of organosulfur compounds, which are thought to be responsible for its flavor and aroma, as well as its potential health benefits. Allicin is made when two substances present in garlic, alliin and allinase, interact - a chemical reaction that only occurs when the cells of the clove are broken down, through cutting, crushing, slicing, or biting. Allicin rapidly breaks down to form a variety of organosulfur compounds. This is an unstable chemical reaction. In other words, the "garlic hotness" does not last forever, and apparently, Allicin has a half-life of about three days (depending on temperature, storage, etc).
Hardneck Garlic is a particularly rich source of organosulfur compounds. When raw garlic cloves are crushed, chopped, or chewed, an enzyme known as alliinase is released. Alliinase catalyzes the formation of sulfenic acids from L-cysteine sulfoxides. Sulfenic acids spontaneously react with each other to form unstable compounds called thiosulfinates. In the case of alliin, the resulting sulfenic acids react with each other to form a thiosulfinate known as allicin (half-life in crushed garlic at 23°C is 2.5 days).
If you are making a raw garlic dish, begin with Porcelain or Purple stripe Hardneck Garlic: Music, German Extra Hardy, Ivan, Montana Zemo, Rosewood Persian Star, Metechi, Purple Glazer, or Bogatyr.
References and Source: Oregon State University. Linus Pauling Institute. Micronutrient Information Center.
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