Is it healthier to wait after cutting garlic before cooking it?

October 17, 2007 7:51 PM

Is it healthier to cut garlic, wait a while, and then cook it (as opposed to cut-then-cook-right-away)?

I swear I just read an article in the past week or ten days about this, and I thought it was in the NYTimes, but searches there do not come up the the article I thought I read there, and google is giving me Botox hits (??!!??!!). There was something about a reaction to being cut that changes the garlic fundamentally, and you get more health benefits if you cut, wait, then cook.

posted by tractorfeed to Food & Drink (16 answers total)

I saw Mark Bittman say this in his video podcast, the one where he's glazing the carrots. Presumably, it's in the Minimalist column from the past week or two, with the discussion of that recipe.

He basically says to let the garlic sit for 15 minutes after cutting, before you use it.
posted by chengjih at 7:57 PM on October 17, 2007

http://fcorpet.free.fr/GaspachoRecipe.html#ail

Garlic crushing: Why is it better to wait?
You should wait for a little while after crunching garlic. Why that? Because garlic is packed with good molecules, but they are not active inside the garlic clove. Inded the cells contain precursors of protective agents (called alliin), and the cells also contain the enzymes (alliinase) that can free the the active molecules (allicin, which gives diallyl sulfide and other compounds). When you crunch or cut garlic, precursors and enzymes are mixed, and the "good reaction" takes place while you wait. If you do not wait but cook the garlic, heat will "kill" the enzymes (60 seconds of microwave fully inactivates alliinase). If you mix or eat the garlic without crunching and waiting, the enzymes are diluted and are less efficient. Got it?

posted by Memo at 7:58 PM on October 17, 2007

Well, there's a theory that cutting things (particularly vegetables and greens) with a metal kife imparts something or takes something away. That is why ceramic knives exist, I believe. Perhaps the article writer believed those things magically returned after 15 minutes.

On preview: "heat will "kill" the enzymes"...

Heat will kill the enzymes anyway (anything above approx 115 degrees). This is why the raw food lifestyle exists.
posted by dobbs at 8:01 PM on October 17, 2007

It may be healthier that way, but crushing the garlic, as opposed to mincing it makes it taste much more bitter. Those same chemical reactions that lead to allinase also result in a much more bitter flavor.
posted by otherwordlyglow at 8:04 PM on October 17, 2007

You're going to get different effects (sometimes widely different) from different preparation methods because they differ in (a) how thoroughly they mix the flavor precursors with the enzymes that produce them, (b) how readily they liberate the flavor molecules, and when, and what catches them, and (c) how active those enzymes are. Crushing or food processing mixes them thoroughly and liberates everything quickly, flavor molecules will survive longer if received by stable lipids (butter, saturated fats) than unstable ones (olive oil), and early heat will tend to shut down the production of the defensive sulfurous compounds with the sharp taste and the long-lasting odor. Garlic that is blanched or roasted whole develops very little of the sharp, rank stuff, whereas mangling it thoroughly by blunt force at moderate temperatures will produce a maximum.

And if there are chemicals in a food that react with metal atoms or ions, then yes, metal knives will affect them. Dunno how many of those products would alter further in 15 minutes. But I don't think that's what he's at here. Nor do I think the proposed health benefits are in the aliinase.
posted by eritain at 9:46 PM on October 17, 2007 [2 favorites]

It might change the flavor, but I seriously doubt it has any non-negligible health implications.
posted by Steven C. Den Beste at 10:42 PM on October 17, 2007

"Many home chefs mistakenly cook garlic immediately after crushing or chopping it, added Dr. Kraus. To maximize the health benefits, you should crush the garlic at room temperature and allow it to sit for about 15 minutes. That triggers an enzyme reaction that boosts the healthy compounds in garlic."

source: New York Times Blog

This was posted on Instapundit, where you might have seen it.
posted by andoatnp at 12:42 AM on October 18, 2007 [1 favorite]

I remember reading something earlier this year about this. the jist of it was, that to obtain the anti-bacterial chemicals found in garlic, the clove needed to be crushed, and the juice exposed to air to start a reaction that maxes out around 15 minutes. Or, after reading the other answers, what andoatnp said
posted by ArgentCorvid at 4:11 AM on October 18, 2007

According to The Worlds Healthiest Foods:
Chopping or crushing stimulates the enzymatic process that converts the phytonutrient alliin into allicin, a compound to which many of garlic's health benefits are attributed. In order to allow for maximal allicin production, wait several minutes before eating or cooking the garlic.

It does not seem that unreasonable to me. Dutch scientists (from Wageningen University) found last year that the same was true for cabbage: pre-cut cabbage had more health promoting glucosinolates than freshly cut cabbage.
posted by davar at 4:27 AM on October 18, 2007

Recent clinical trials of garlic-as-prevention turned up squat. Do what you want.
posted by a robot made out of meat at 4:38 AM on October 18, 2007

Garlic works a lot better when activated, preferably by flash-frying it in olive oil for a few seconds. Not enough to brown, just enough to tan. Tremendous difference.
posted by rokusan at 7:42 AM on October 18, 2007

"Recent clinical trials of garlic-as-prevention turned up squat. Do what you want."

This is false. It is now showing to be good for the heart.
posted by 6:1 at 8:22 AM on October 18, 2007

I'm thinking of this and all the other garlic related studies which pop up there. A review article
posted by a robot made out of meat at 2:15 PM on October 18, 2007

http://www.sciencedaily.com/releases/2007/10/071016131534.htm

Newer study.
posted by 6:1 at 11:22 AM on October 19, 2007

Like many science studies, new ones often contradict others. Who knows what the truth really is.
posted by 6:1 at 12:44 PM on October 19, 2007

FYI, I'm catching up with all the old magazines lying around and you may have seen this as a little unsupported blurb in Real Simple. (Personally, I think the theory sounds ludicrous, but what do I know about enzyme reactions?)

Also, ceramic knives do have the added benefit of not turning things like basil black after chopping, but that's not why they exist. Try one once - you'll never go back to metal, even fancy German metal.
posted by CunningLinguist at 5:28 AM on October 30, 2007