Bad-tasting onions and garlic in a crockpot?

June 27, 2012 1:20 PM

Do crockpots make onions and garlic taste bad in your experience? If so, why does it happen?

I am at the point where I don't want to use the crockpot if the recipe has garlic and/or onions, because the process imparts a gross taste that I can't really describe. Has anyone else had this experience, and if so, do you know why it happens?

posted by Stewriffic to food & drink (19 answers total)

I can't stand cooked onions in general if they haven't been sauted first. If I'm making soup or stew (in the crockpot or otherwise) I always saute the onions (and garlic) in a little oil first until the onions become translucent.

I do it in a separate skillet, though you can also also crank your empty crockpot up to hi and add oil and onions (though this takes forever.)
posted by BrashTech at 1:27 PM on June 27, 2012

I haven't had that experience, really, but I do know that a lot of the taste of garlic and onions has to do with volatile compounds that gradually degrade if they're cooked a long time, or out in the air. It's the reason cooked or roasted garlic is so much mellower than fresh garlic, or caramelized onions so much less pungent than fresh onion slices. I'm thinking that either you just don't like what is left of the flavor of long-cooked alliums, or that somehow the crockpot just creates an off-taste when those compounds recombine.

Do you use a crockpot with a ceramic insert?
posted by Miko at 1:28 PM on June 27, 2012 [1 favorite]

Yes, I've had the same experience with four different crockpots of varying age, but which have in common the ceramic insert. Its really an off-putting flavor, and distinct but indescribable in any words I can find.
posted by Stewriffic at 1:32 PM on June 27, 2012

I can say that the only time garlic has done something strange was in a slow cooker. I don't know what happened, but my garlic turned blue and this had never happened previously with the same ingredients. I think I established that it was still edible, but I couldn't bring myself to do it. I'm wondering if this occurrence might be related to yours.
posted by sunshinesky at 1:32 PM on June 27, 2012

Are you sauteeing them first? Because if you aren't, I know exactly what you mean. In every crockpot thing I make, I saute the garlic and onions first to avoid that flavor.
posted by something something at 1:34 PM on June 27, 2012 [2 favorites]

That said, I love roasted garlic and caramelized onions, so it's not that. Maybe there's something to the non-sautéing aspect, becuse I do out them in there raw.
posted by Stewriffic at 1:35 PM on June 27, 2012

I'm sure that cooking onions and garlic for a long time at 190-200 degrees would create a different flavor from cooking at a higher temperature or not at all. I may know the flavor you're talking about, but it's impossible to say without tasting it - it's the same flavor that my burps have after I eat garlicky sausage. Definitely recognizable as onion/garlic, but not very pleasant.

The only thing I can recommend is to saute the garlic and onions until caramelized first (on preview, what something something said).
posted by WasabiFlux at 1:35 PM on June 27, 2012

Maybe there's something to the non-sautéing aspect, becuse I do out them in there raw.

Yes. There is something to this, absolutely. Sautee onions and garlic first, no matter what you are making. If you add raw onions to a dish to cook, you will get that "boiled onion" taste and it's not pleasant.
posted by Fairchild at 1:37 PM on June 27, 2012 [4 favorites]

I think unsauteed crockpot onions and garlic sort of get steamed rather than baked, which would impart the same flavor as onions and garlic being boiled, which would be Not Good.
posted by something something at 1:38 PM on June 27, 2012 [1 favorite]

Hm though, it does the same with garlic flakes or powder. Would that make a difference?
posted by Stewriffic at 1:40 PM on June 27, 2012

It could be the water, too. Sunshinesky mentioned garlic turning blue - I had that happen too, in a salad dressing. It turned out to be something in the water that reacted with the garlic to form copper something something, which was the source of the blue. Would you consider trying distilled or filtered water, just for the sake of the experiment?
posted by LN at 1:41 PM on June 27, 2012 [3 favorites]

It's the low temperature. Boiled/steamed garlic and onions also have a weird/bad taste.

Definitely roast/sautee them first.
posted by wongcorgi at 1:41 PM on June 27, 2012

Forgot to add: Sautee sliced or chopped onion until translucent. About five minutes or so on medium heat and then add. Even if the recipe doesn't' call for it, I always brown beef, and sautee onions and garlic before adding to crockpot.
posted by Fairchild at 1:41 PM on June 27, 2012

Wait. This does not happen when I make stock or stew with raw garlic and onions, and I boil them. Only with the crockpot. So I'm not yet convinced about the rawness being the issue.
posted by Stewriffic at 1:46 PM on June 27, 2012

The garlic turning blue (or green) thing happens a lot in pickling and it's because enzymes in garlic can turn that color when reacting with an acid (like vinegar or lemon juice). It's not harmful.
posted by Miko at 2:00 PM on June 27, 2012 [3 favorites]

I make caramelized onions in the crock pot sometimes and I think they're delicious. (Ingredients: onions and butter.)
posted by mskyle at 2:11 PM on June 27, 2012 [1 favorite]

I know that when you cook onions or garlic sous vide, it is well known that it imparts an odd off-taste. We use garlic and onion powder in sous vide recipes instead. The low heat of the crockpot might bring about similar off tastes. I would describe the flavor of sous vide garlic as oddly metallic.
posted by Lame_username at 2:52 PM on June 27, 2012

I've had this happen to me in a ceramic Le Creuset thing with garlic and onions, and yes, the garlic turned blue. I stopped doing that.

(This was generally at mid-high temps (350 or so), for 30-45 minutes.)
posted by TonyRobots at 2:53 PM on June 27, 2012

Maybe it happens at low temperatures when plenty of oil is present, or in a more acidic or alkaline solution. What kinds of things do you cook that turn out with a weird taste?
posted by WasabiFlux at 4:47 PM on June 27, 2012