Researchers in Japan compared fresh garlic with garlic preserved in water,
alcohol, and vegetable oil, specifically measuring a key ingredient called
allicin. Allicin is the main active ingredient in garlic and the chemical
responsible for its characteristic smell.
Allicin is widely promoted for its antibacterial properties. Some studies
have shown that allicin helps fight infections and may help prevent
bacteria-related food poisoning. Other research has
suggested that the compound can help against blood clots and certain
Allicin is fragile and disappears quickly, leading the study's researchers
to question whether various storage methods would affect its levels.
The team's experiments revealed that fresh crushed garlic is more stable and
maintains higher levels of allicin than preserved versions.
Garlic stored in water at room temperature is better than garlic preserved
in vegetable oil. Allicin levels decreased by about half after about six days
in water, but the vegetable-oil storage method robbed garlic of half its
allicin in a few hours.
Garlic's antibacterial properties declined as allicin levels dropped.
However, researchers believe the allicin breaks down into compounds that may
still be helpful.