slow cooker vs pressure cooker?

November 5, 2015 10:28 AM

Do slow cookers have any advantages over pressure cookers, in terms of the final result? The differences in cooking process are clear to me -- what I'm trying to understand if there are results that you can achieve with one appliance over the other.

I currently have a slow cooker. But am curious about pressure cookers. A quick google on "slow cooker vs pressure cooker" yields many links which mainly focus on the fact that one is slow and one is fast.

If relevant, I mainly like to cook rich stews, both meat and vegetarian (especially beans).

Thanks.

posted by wutangclan to Food & Drink (28 answers total)

not sure if this is a valid answer, but if you're cooking kidney beans then you need to boil them for 10m first if you use a slow cooker (i'm just trying to think of how the two could be different, and temperature is one difference, which leads to that problem).

off the top of my head i can't think of any other example where long time and higher temp/pressure don't produce similar results.
posted by andrewcooke at 10:32 AM on November 5, 2015

Response by poster: Do the kidney beans come out tasting different?
posted by wutangclan at 10:47 AM on November 5, 2015

I thought the difference was that you got more nuanced flavors with a slow cooker.
posted by spunweb at 10:49 AM on November 5, 2015

I would venture to say that, if anything, it would be the other way around -- that the final product from a pressure cooker will generally be better than the slow cooker, but that's more my gut feeling than any empirical evidence. I would expect the pressure cooker to have less negative impact on overall texture of a dish. Maybe that's not super important for stew.
posted by briank at 10:49 AM on November 5, 2015

Do the kidney beans come out tasting different?

i don't know. if you don't boil them, they are poisonous (boiling them destroys the poison, as does cooking them in a pressure cooker) (sorry - i should have explained that more clearly in my first reply!)
posted by andrewcooke at 10:52 AM on November 5, 2015

What I have found so far is that pressure cooking can be too intense, doing weird things to the texture of a lot of foods. I often complain about slow cookers resulting in very bland food, in part because of the extra liquid you put in (and pull out, at least in the case of meat), but also because not a lot of aromatics can stand up to hours and hours of heat.

But there are ways of compensating for those issues with a slow cooker that are harder to pull off with pressure cooking. Pressure cooking is a bit of a blind process with much less margin for error, and you can't really check halfway through to see if you've asploded your beans or your short ribs are still unchewable.

The flavor difference is almost a factor of how much you screw up on one or the other. If you use a pressure cooker, you only have a few minutes to get flavor into the beans. If you underseason in the slow cooker and don't taste and correct course at some point, you'll have the same problem.

The texture difference is a bigger deal to me. It's so easy to over/undercook in the pressure cooker, and overcooked beans do not taste good to me. But if you do it right, you can get a comparable result to other methods.
posted by Lyn Never at 10:56 AM on November 5, 2015 [7 favorites]

I have both a slow cooker and pressure cooker. Haven't used the latter much yet, but in my limited experience, the food tasted pretty much the same either way.

I was only cooking heavily spiced/sauced things in the pressure cooker though, so that's probably a factor.
posted by sharp pointy objects at 10:56 AM on November 5, 2015

With tough meats (e.g. pot roast or stew meat) the thing you're going for is collagen breakdown, where the stuff that binds the meat together breaks down and turns into gelatin. When you cook meat the cells constrict and squeeze out a lot of water. When collagen converts to gelatin, this adds something we perceive as moisture, but it isn't water added back to the muscle. We're just fooled into thinking it is.

The thing about that conversion from collagen to gelatin is that it happens above the temperature we call meat "well done" and it takes a long time at that temperature . Pressure cooking raises the temperature above that range so you'll cook the crap out of your beef (squeezing out even more moisture) and also not get the collagen breakdown you want because it won't spend enough time in the right temperature range. So score one for a slow cooker. (There's also an answer on the cooking stack that goes into why some meats work well in a pressure cooker but others don't, but I've never cooked those meats so this was new to me.)

OTOH with beans and grains the higher temperature and pressure totally pays off in cooking time, so score one there for the pressure cooker.
posted by fedward at 10:58 AM on November 5, 2015 [5 favorites]

I think the flavors of food from a pressure cooker tend to be fresher because pressure cookers exclude the ambient free oxygen slow-cooked food is exposed to.

Oxidized flavors may be desirable in some things -- mildly oxidizing coffee seems to me to develop chocolate overtones -- but oxidized foods with a significant amount of fat taste rancid.
posted by jamjam at 11:00 AM on November 5, 2015

I note mostly differences in texture between the two. So, for instance, cooking potatoes in a slow cooker can handily dissolve a starchy potato while a pressure cooker can deliver a held-together product. I think this is largely a consequence of the mechanics of each set-up: a slow cooker gives a lot of opportunity for food to jiggle around, even just a little bit, over hours at high temperature, encouraging foodstuffs to break and bubble and congeal; the pressure cooker heats quickly and is finished, with much less jostling about at the temperatures where structural integrity is lessened.

Beans are a very general instance in which I prefer the slow cooker. Not for all beans, mind you (chickpeas in a pressure cooker are wonderful). If you're looking for a rustic, dark pot liquor, you're looking for things like oxidation and nonenzymatic browning. These things come very easily in slow cookers, and with difficulty (or not at all) in pressure cookers.

Vegan, so can't speak to meats.
posted by late afternoon dreaming hotel at 11:01 AM on November 5, 2015

Here is some more info on kidney beans (I had never heard of this problem, so thanks, andrewcooke)

"Raw kidney beans contain relatively high amounts of phytohemagglutinin, and thus are more toxic than most other bean varieties if not pre-soaked and subsequently heated to the boiling point for at least 10 minutes. The US Food and Drug Administration recommends boiling for 30 minutes to ensure they reach a sufficient temperature long enough to completely destroy the toxin.[2] Cooking at the lower temperature of 80 °C (176 °F), such as in a slow cooker, can increase this danger and raise the toxin concentration up to fivefold.[3] Canned red kidney beans, though, are safe to use immediately."
Source
posted by H21 at 11:15 AM on November 5, 2015 [3 favorites]

Response by poster: Regarding the kidney beans, I get that an extra step of pre-boiling is necessary to avoid poisoning. Different methods require different steps. Understood.

But the information I'm really after is regarding the end result. i.e. if I dump my slow cooker for a pressure cooker, will I be trading time saved for taste/texture? Are there certain results that I can't achieve with a pressure cooker that I can with a slow cooker?

I guess the other thing I should mention is that I live in a small apartment without enough space to store both gadgets...hence the need to make a choice.
posted by wutangclan at 11:25 AM on November 5, 2015

I'm completely off the slow cooker (other than keeping things warm for serving). For long braises, I only use an enameled cast iron dutch oven in the oven around 300, because you get real Maillard reaction. The slow cooker obliterates everything; chewiness, yes, but also flavor.

Meanwhile, I mostly only use the pressure cooker for stock, but have done pork belly, short ribs, etc in it in the past. More concentrated flavor than slow cooker, but not as much as a "real" oven braise.

Beans in a dutch oven for hours (after soaking overnight) are amazing.

Kenji Lopez-Alt is mostly responsible for my change in behavior (and seeing the evidence for myself) and he uses this electric pressure cooker that (I think) does slow cooking as well.
posted by supercres at 11:34 AM on November 5, 2015 [4 favorites]

I do a lot of bean cooking with a pressure cooker.
Usually I just use the PC to process the beans , then finish the dish with conventional cooking because the beans need longer and the taste is better.
PC tends to prevent mealiness and disintegration, however it can give a "canned" taste especially to dark beans like pinto and borlotti. In fact this taste occurs with other foods as well.
Light colored beans like navy and cannelini come out well with PC.
I don't use it at all for chickpeas or lentils as they don't require as much processing.

I always use a slow cooker for baked beans with good results.
posted by canoehead at 11:46 AM on November 5, 2015 [1 favorite]

Does it need to be an or decision? Some devices do both
posted by kookywon at 11:48 AM on November 5, 2015 [5 favorites]

Can you caramelize onions in a pressure cooker?
posted by peppermind at 11:57 AM on November 5, 2015 [1 favorite]

Get one of these and experiment.
posted by soren_lorensen at 11:59 AM on November 5, 2015 [1 favorite]

I'm guessing you're looking at an electric pressure cooker?

I love my stovetop Fagor set in part because the pots themselves are fantastic heavy clad that I use all the time for non-pressure applications.

If you're going to get an electric pressure cooker, get the combo that has the slow cooker, rice cooker, fryer, steamer etc. The Instant Pot is hugely popular on the pressure cooker sites I read.
posted by Lyn Never at 12:07 PM on November 5, 2015 [1 favorite]

Aside from taste and texture, I would never leave a pressure cooker alone while going out of the house but usually do for a slow cooker. The difference too is in the amount of time each takes. The slow cooker clearly takes much longer.
posted by Postroad at 1:27 PM on November 5, 2015 [1 favorite]

I do my slow cooking in the oven in a Dutch oven, and I do beans that way because to me, they taste better slow-cooked.
But I love my pressure-cooker, and I use it almost weekly, sometimes more. Some stews are much better in a pressure-cooker than in a normal pot or a slow-cooker. And the ability to make a good soup, veg or meat, on a work-day is just gold during winter. Every time I roast a chicken or anything else with a bone in it, I make a stock in the pressure-cooker while cleaning up after dinner. A pot roast in a pressure cooker is delicious and can be done on a Tuesday (but you might want to give it 10 mins under a broiler - there is a maillard reaction in the cooker, so the tastes are there, but the presentation is not optimal).
I have yet to find a purpose for the slow-cooker that my oven+dutch oven cannot handle. But the pressure cooker has expanded my everyday cooking options infinitely. There are still things I haven't explored, like risotto, which is supposed to be very good, or steaming, which is supposed to better than normal steaming for taste and health.
posted by mumimor at 1:32 PM on November 5, 2015 [1 favorite]

Instant Pots are very well-reviewed; I don't want one as I find stuff with electronics that does the same stuff as non-electronic equivalents is generally a bad idea. The electronics will fail long before the rest of it. Given the space to store only one, I'd store a standard pressure cooker.

I have both, and the slow cooker has not crawled out of the basement since I started using a pressure cooker. I was not a huge fan of slow cooker slop in the first place, and asking around has found the consensus tends to be that the point of it is convenience, full stop. There's nothing useful going on except for the simplicity and ease of use. I agree with slowcres. The only thing I use a slow cooker for is keeping stuff warm at parties. My answer to Are there certain results that I can't achieve with a pressure cooker that I can with a slow cooker? would be yes -- you will find it more difficult to make bland and unevenly cooked slops.

It seems telling that you don't see industrial-sized ones pressed into service in restaurant kitchens. If slow cookers were offering good results exclusive to slow cooking, people selling food would certainly capitalise on a cheap and low-effort way to get those good results. And yet.

My soups are notably better in a pressure cooker. Veg soup is a delight. I pressure-cook a broth; it cooks up beautifully in no time. Beans/grains go in next, bit more cooking. Chopped veg goes in, and then very quickly it is magically infused with the broth, perfectly cooked through, but never overcooked. You know those awful rounded potatoes one gets out of overcooked soups? A thing of the past. Potatoes are a wonderful thing to pressure cook on their own, too. It can be a bit fiddly to time but doesn't take long to learn, and when you under-estimate it's not hard to put the lid back on, or just boil it a bit longer. I disagree that it is difficult to check on the contents; modern ones have a quick release valve.

There is a major disclaimer here, though: I am a vegetarian and I have no idea at all what either of these appliances do to any kind of meat.
posted by kmennie at 1:35 PM on November 5, 2015 [3 favorites]

We have an Instant Pot. It's a few years old now (we have a previous model).

Grain and soups are really good in it. Beans work well. Stews work well. Rice works spectacularly well.

By well I means cooks to a desirable, unmushy texture, cooks very quickly and does it every single time.

It can slow cook too, but we almost never use that feature.

If you're on the fence about pressure cooking, I would recommend it. It compares well in cost to many traditional pots, and it's as easy to use as a good rice cooker (and made with that technology).
posted by bonehead at 2:29 PM on November 5, 2015

I am another Instant Pot fan. Its true the electronics are a risk, but a) a pressure cooker you can safely walk away from is a great convenience (IP will hold pressure for the specified time and then hold at 175f afterwards) and b) when our IP threw an error code after two years of heavy service, we wrote the company, and they emailed pictures of the electronics and troubleshooting suggestions. Which fixed it! Very nerdy company.
posted by clew at 6:25 PM on November 5, 2015

It seems telling that you don't see industrial-sized ones pressed into service in restaurant kitchens.

This is because restaurant kitchens have highly controllable stove burners (and staff to notice if the kitchen is on fire), steamers, water baths, sous vide, rotisserie ovens, warming drawers, etc. Those are industrial slow-cookers. The consumer-grade slow-cooker is an affordable tool that replicates the most applicable functions of those items for home use.
posted by Lyn Never at 7:14 AM on November 6, 2015 [2 favorites]

A major difference between pressure cooked and slow cooked is the amount of drying that happens. Slow cooking, particularly long slow cooking, drives off a lot of water. In adapting to the sealed Instant Pot, we've had to adjust the levels of water we add down a lot, as it all stays in the vessel. This is true even for things like rice and grain. The difference between even a covered pot on the stove and the pressure vessel for the 10 minutes rice takes in the Instant Pot is significant: 2:1 on the stove, 1.5:1 in the pressure cooker.

Sometimes drying is the worst in a slow cooker (crusty stews), but a well-designed recipe relies on it, to reduce a sauce for beans, for example. So that can take some adjusting.
posted by bonehead at 7:44 AM on November 6, 2015

I use both but for different things. If I'm going to use beans in another dish I almost always use the slow cooker. I find the pressure cooker doesn't give the right texture - except for chickpeas. I also use the slow cooker for making stock (the pressure cooker makes fine stock but the slow cooker is less fussy I think for this task). Occasionally, I'll use it for keeping things warm. Ultimately, I think it is a less fussy cooking style but I think the results, in terms of a full meal, can be lack lustre. As a way prepare components of meal or very simply made things (I've used it for steel cut oatmeal for instance) I think it is a good device.

The pressure cooker sees more active direct use for full meals. My favorite is usually risotto [technique derived via the Modernist Cuisine]. I've used it for grains, sauces, pasta (I found this a bit tricky to time right), cooking dense root vegetables [I like this caramelized carrot soup recipe].

I've used both for meats. Slow cooker is fine for very tough cuts but requires that you sear the meat prior to cooking in the slow cooker. Also you have to make sure to check the seasonings as long cooking seems to muddy the flavours. I wouldn't use a tender cut in a slow cooker. Pressure cooker is able to give brighter, more distinct flavours, and is good for tender cuts and tougher ones. You need to watch your time as it can get over cooked easily.

If I make baked beans, I use neither and rely on slow cooking in the oven. I find neither the pressure cooker or the slow cooker give my preferred desired texture.
posted by Ashwagandha at 9:50 AM on November 6, 2015

I love my new pressure cooker but keep in mind that when something says it takes x minutes to cook, that is under pressure. So yes, it may only take me 12 minutes to make rich, flavorful chicken soup, but it might take 10 minutes to get up to pressure (you can reduce this a bit by bringing chilled foods closer to room temp) and another 10 minutes to release the pressure. That's still fast, but it still the one thing I didn't know before I got the pressure cooker.

My mother said the chicken soup I made was one of the best she'd tasted, and it was just chicken and onion/carrot/celery, and the carnitas I've been making for years on the stove was really noticibly even better. I have an electronic pressure cooker which lets me release the steam manually which can make a big difference in the texture of your food once it's cooked. It also has other functions like keep warm, sautée, etc.

nth-ing that your oven is a slow cooker. I also debated the two appliances and decided the pressure cooker was something I couldn't replicate. I wouldn't leave either an oven or a pressure cooker on if I wasn't there, but then again I would be extremely anxious if I left a slow cooker going but that's my own hang up.
posted by Room 641-A at 10:35 AM on November 6, 2015

Let me add that one downside for me personally is that a lot of pressure cooker recipes seem to involve grains which is a drag if you are low-carb or paleo. (On the plus side, the chicken breast cooked in the pressure cooker always comes out extremely moist.)
posted by Room 641-A at 10:41 AM on November 6, 2015