Garlic Compounds. Half-Life of Garlic "Hotness" after Crushing or Chopping.
Updated: Mar 31
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 is 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.
Garlic is a popular ingredient in many cuisines, and it is known for its strong flavor and health benefits. However, garlic loses its potency quickly after it is cut or minced. The half-life of garlic is about 2.5 days, meaning that half of the allicin in garlic is lost after 2.5 days.
Allicin is the compound that gives garlic its characteristic flavor and health benefits. It is also a powerful antioxidant, and it has been shown to have antibacterial, antiviral, and antifungal properties. When garlic is cut or minced, the allicin is released from its cells. This allicin is then rapidly broken down by enzymes in the garlic. The rate of breakdown is affected by a number of factors, including the temperature, the pH of the environment, and the presence of other compounds.
At room temperature, the half-life of allicin is about 2.5 days. This means that half of the allicin will be lost after 2.5 days, and half will remain. After about 5 days, only one-quarter of the allicin will remain, and so on.
The half-life of allicin can be extended by storing garlic in the freezer. In the freezer, the half-life of allicin is about 7 days. This is because the cold temperature slows down the activity of the enzymes that break down allicin.
If you want to maximize the health benefits of garlic, it is best to consume it soon after it is cut or minced. You can also store garlic in the freezer slow down the breakdown of allicin.
Cooking garlic can reduce the amount of allicin it contains. Allicin is the compound that gives garlic its characteristic flavor and health benefits. It is also a powerful antioxidant, and it has been shown to have antibacterial, antiviral, and antifungal properties. When garlic is cooked, the allicin is broken down into other compounds. These compounds still have some health benefits, but they are not as potent as allicin.
The amount of allicin that is lost when garlic is cooked depends on a number of factors, including the cooking method, the temperature, and the duration of cooking. In general, cooking garlic for a longer period of time or at a higher temperature will result in a greater loss of allicin. However, there are some cooking methods that can help to preserve the allicin content of garlic.
One way to preserve allicin is to cook garlic slowly at a low temperature. This method is often used in Asian cooking. Another way to preserve allicin is to add garlic to dishes at the end of cooking. This will help to minimize the amount of time that the garlic is exposed to heat. If you want to maximize the health benefits of garlic, it is best to consume it raw or cooked using a method that preserves its allicin content. However, even cooked garlic still has some health benefits, so you don't have to avoid it altogether.
Garlic and Organosulfur Compounds
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.
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