24 replies to this topic

[devlin]

I'd like to try making duck confit, but I'm wondering whether using fats other than the actual duck fat is, like, sacrilege, or something. Because frankly, where in the world do you get the amount of duck fat called for in a duck confit without roasting 40 ducks in a row first?

Googling, I see substitutions such as olive oil, canola, lard, etc. Is this okay? Do they work as well in terms of preserving the duck? Is one better than another?

Help?

[david coonce]

Honestly, You can use any fat. Olive oil is fine, although it will get expensive once you realize how much oil you're going to need. If you call a specialty butcher you can probably order buckets of duck fat. That's how restaurants get it - they generally don't render the fat themselves, just get a bucket of duck fat and heat it until it's liquid.
I would ask around your area - I'm sure somebody in Louisville will have a source for duck fat in buckets, and if that fails, I'd go with a blend of half olive oil and half-lard.
Good luck. Duck confit is one of the finest things on earth!

[devlin]

Honestly, You can use any fat. Olive oil is fine, although it will get expensive once you realize how much oil you're going to need. If you call a specialty butcher you can probably order buckets of duck fat. That's how restaurants get it - they generally don't render the fat themselves, just get a bucket of duck fat and heat it until it's liquid.
I would ask around your area - I'm sure somebody in Louisville will have a source for duck fat in buckets, and if that fails, I'd go with a blend of half  olive oil and half-lard.
Good luck. Duck confit is one of the finest things on earth!

Now why didn't I think of that. Fabulous suggestion. Thank you!

[syoung68]

D' artagnan also sells duck fat if you can't find a local source.

https://www.dartagna...sp?criteria=618

[david coonce]

Yep, D'Artagnan's is good, albeit a little pricey, and if you talk to local restaurants (or someplace like Lotsa Pasta), they can probably put you in touch with a distributor named European Imports, where a giant tub of duck fat is pretty darn cheap. You can freeze whatever you don't use and it's good forever.
Good luck, again. Duck Confit is one of those things people freak out about at restaurants, but if they only knew how easy it was to make it....

[slkinsey]

If you have the capability, confit is one area where sous vide can really be a cost saver. I recently made some duck leg confit, sealing each leg in an individual pouch with some fat. The beauty of this is that you don't need to use much fat. I only used around a tablespoon of fat per duck leg. When you vacuum the bag, the leg is surrounded by a thin layer of duck fat. It's also nice to have the legs in individual packages.

[Chris Amirault]

I've found that the rendered trim from a whole duck gives nearly enough fat to confit the legs on that duck. I came up with this method as a way to get the most out of each bird, and it works like a charm -- that is, if you don't mind sacrificing the cracklin's.

[devlin]

All fabulous suggestions. Thanks so much!

[Busboy]

Hudson Valley has by far the cheapest duck fat I've ever seen -- on a cost per pound basis it's just about the same as buying a duck and rendering it yourself. The shipping cost is a bit of a bitch, though, so you might want to go in with friends or just order a foie gras to go with.

Personally, I'd resolved to cook duck more often so I don't have to mail order again, but, of course, confit season is upon us and I'm coming up short again...

[muichoi]

One point often neglected is that the fat from roasting must be poured off almost instantly-browned/burnt fat is hopeless for any kind of reuse and must be discarded, it's really pretty unhealthy stuff. On the other hand, if it never gets above 85c or so it's amazing how long it lasts, through many reuses.

[markk]

Where are you getting the legs from? and how many are you confit-ing? I'm of the belief that even if you put 4 legs tightly packed into a narrow vessel, they will render enough of their own fat to cover themselves in it.

Also to the slkinsey, you're not actually cooking them sous-vide, are you or just sealing them after they're done? The idea of confit is that the moisture content evaporates (through the fat cover) and when there's no moisture left in the meat, it is preservable because there's no oxygen to go rancid, at which point leaving it under an airtight covering of fat is safe. If you're cooking it in a sous-vide package, the moisture is surely not escaping?

edited to add slkinsey's name instead of calling him "the sous-vide person"

Edited by markk, 30 October 2007 - 05:45 PM.

[Chris Hennes]

If you have the capability, confit is one area where sous vide can really be a cost saver.  I recently made some duck leg confit, sealing each leg in an individual pouch with some fat.  The beauty of this is that you don't need to use much fat.  I only used around a tablespoon of fat per duck leg.  When you vacuum the bag, the leg is surrounded by a thin layer of duck fat.  It's also nice to have the legs in individual packages.

In Wolfert's book she describes this, but implies that the confit doesn't age the same way as a traditionally-made confit would. Is this your experience as well? Does it have to do with the vacuum sealing creating a seal that is too airtight? I had wondered if pricking the bag before putting them into storage might allow just a tiny bit of oxygen in without allowing it to spoil.

[qrn]

You can buy a tub of it from Whole foods. Its only 6 or 7 bucks...
Or do it easily Sous viede(sp) with the rendered fat from one duck. (legs only...)

Bud

[thenextmeal]

You don't want to use anything other than duck fat. But here's a trick...

I trim off the breasts, remove the two legs, then render the fat from the remains. Now - this is the trick - seal the legs covered with about half the rendered fat (that's all you'll need to cover them) in a vacum bag or a zip lock if you don't have a vac sealer and cook sous-vide for 8 or 10 hours.

If you are not yet a home vid-er, it's easy. Get a good sized stockpot -minimum 6 or 8 quarts and fill with H20. Heat to about 180° then lower heat and watch temp (I use a cheap digital imersion therm. with an alarm) for 30 minutes or so to be sure it is stabilized at that around that temp or so. Once you are confident, add the duck. FYI the temp will go down at that point - you can increase the heat for a bit and monitor it or just let it return on it's own. 8 or so hours later...

By the way, save the extra rendered duck fat for roasted potatoes. Oo-la-la!

And the sous-vide notes apply to cooking anything you want to cook this way as an alternative to a traditional braise. Cooking fish, vegetables, eggs etc this way is a bit more complicated and less forgiving, but not beyond my down and dirty method once you do the basic 180° version a few times.

[slkinsey]

Also to the slkinsey,  you're not actually cooking them sous-vide, are you or just sealing them after they're done?  The idea of confit is that the moisture content evaporates (through the fat cover) and when there's no moisture left in the meat, it is preservable because there's no oxygen to go rancid, at which point leaving it under an airtight covering of fat is safe.  If you're cooking it in a sous-vide package, the moisture is surely not escaping?

I've never heard the theory that the confit process removes all the water (which is presumably what you mean by "moisture") from the meat. And, having made confit using the traditional process many times, I have to say that this is not my experience (there is almost always some liquid at the bottom of the jar). Indeed, duck legs from which all the water had been cooked out would be tough, dry and unappetizing.

I also don't quite get the chemistry of "there is no oxygen to go rancid." What would be going rancid, exactly? And how is oxygen being removed by using an open container? If anything, I'd think that heating the confit above the boiling point of water (which would be necessary for the evaporation you suggest takes place) for a long period of time would increase oxidation of the fat, and therefore increase the possibility of rancidity developing over time. As for preservation... afar as I know, what happens is that you cook the duck legs for a long time, effectively sterilizing them, and then you "seal" them in an airtight covering of solidified fat -- fundamentally "canning" the duck legs without using a can. As far as I can tell, the sous vide process should minimize oxidation more than the traditional method.

[Chris Hennes]

If anything, I'd think that heating the confit above the boiling point of water (which would be necessary for the evaporation you suggest takes place) for a long period of time would increase oxidation of the fat, and therefore increase the possibility of rancidity developing over time.

This isn't quite true: if you take a cup of water and put it on a hot plate for 8 hours at 180 degrees it will all evaporate, without ever "coming to a boil." So I think what markk is saying is that cooking at 180 F for that long causes the moisture to evaporate. I agree that that has not been my experience.

As for preservation... afar as I know, what happens is that you cook the duck legs for a long time, effectively sterilizing them, and then you "seal" them in an airtight covering of solidified fat -- fundamentally "canning" the duck legs without using a can.  As far as I can tell, the sous vide process should minimize oxidation more than the traditional method.

Exactly, with the exception that the fat is not actually completely airtight: duck fat, in particular, is quite porous. This is why Wolfert recommends using a thin layer of lard to seal your jars for long-term storage. I'm just guessing here, but I was thinking that the ripening process depends on this porosity, and that if you completely seal the confit in vacuum pouches, it will not ripen at all. So I was wondering if you could "simulate" the porosity by poking a small hole in yoour vacuum bag in an area where there is a relatively thick fat deposit, allowing just a tiny bit of oxygen in.

[slkinsey]

I don't have it in front of me, but I looked up "confit" in McGee's book last evenening, and I recall him saying something to the effect that a slight rancidity can be part of the traditional flavor of aged confit.

WRT the evaporation, while I don't disagree with your example of the one cup on a 180F hotplate evaporating after 8 hours, it's not clear to me that you will evaporate the same one cup of water in 8 hours if it's covered up in 6 cups of fat (not to mention 8 duck legs). I can't imagine how much water would really be cooked off from within the duck legs themselves (which exude liquid throughout the cooking process), but there's no way it could even approach all of it. When I've made confit using the traditional method, there has always been plenty of liquid at the bottom of the cooking vessel. Typically, I'd try to minimize liquid in the actual storage jar by placing the cooked legs in the jar and then pouring only fat around them. Even then, some liquid still usually comes out of the legs and collects at the bottom of the jar.

[Chris Hennes]

WRT the evaporation, while I don't disagree with your example of the one cup on a 180F hotplate evaporating after 8 hours, it's not clear to me that you will evaporate the same one cup of water in 8 hours if it's covered up in 6 cups of fat (not to mention 8 duck legs).  I can't imagine how much water would really be cooked off from within the duck legs themselves (which exude liquid throughout the cooking process), but there's no way it could even approach all of it. 

Yeah, definitely - I don't think we're disagreeing on this point . I like your analogy to canning: that helps to think about what you are really doing. Clearly, cooking anything at 180 F for 8 hours is enough to sterilize it to foodservice standards (if I recall correctly, pasteurization doesn't actually take anywhere near that long at that temp). So we're cooking and preserving, then sealing with fat. I would expect confit done in a vacuum pouch to last extremely long, as compared to the traditional method of storing covered in fat only. I'm not sure on the porosity of the plastic bags (it is non-zero) but I suspect that it is less porous than the fat, so should provide a better seal. This would explain the lack of aging ability, and provide support for a very long shelf-life.

[markk]

If anything, I'd think that heating the confit above the boiling point of water (which would be necessary for the evaporation you suggest takes place) for a long period of time would increase oxidation of the fat, and therefore increase the possibility of rancidity developing over time.

This isn't quite true: if you take a cup of water and put it on a hot plate for 8 hours at 180 degrees it will all evaporate, without ever "coming to a boil." So I think what markk is saying is that cooking at 180 F for that long causes the moisture to evaporate. I agree that that has not been my experience.

As for preservation... afar as I know, what happens is that you cook the duck legs for a long time, effectively sterilizing them, and then you "seal" them in an airtight covering of solidified fat -- fundamentally "canning" the duck legs without using a can.  As far as I can tell, the sous vide process should minimize oxidation more than the traditional method.

Exactly, with the exception that the fat is not actually completely airtight: duck fat, in particular, is quite porous. This is why Wolfert recommends using a thin layer of lard to seal your jars for long-term storage. I'm just guessing here, but I was thinking that the ripening process depends on this porosity, and that if you completely seal the confit in vacuum pouches, it will not ripen at all. So I was wondering if you could "simulate" the porosity by poking a small hole in yoour vacuum bag in an area where there is a relatively thick fat deposit, allowing just a tiny bit of oxygen in.

I searched for the reference where I originally learned this but couldn't find it last night. I thought it was McGee. It had to do with methods of preserving meat and a discussion of salting and drying, and an explanation of how air-drying meat, and salting fish, are twp methods of removing the moisture (oxygen) that allows meat to go bad, and that the "confit" process in which the moisture evaporates slowly until you see no more steam rising through the fat means that when it cools and the fat forms a seal, the dried (no water) meat is preserved under the fat. I'll keep searching for a source to cite unless somebody here bails me out.

[Chris Hennes]

It had to do with methods of preserving meat and a discussion of salting and drying, and an explanation of how air-drying meat, and salting fish,  are twp methods of removing the moisture (oxygen) that allows meat to go bad, and that the "confit" process in which the moisture evaporates slowly until you see no more steam rising through the fat means that when it cools and the fat forms a seal, the dried (no water) meat is preserved under the fat.  I'll keep searching for a source to cite unless somebody here bails me out.

Sorry, I did't mean to come across as overly critical - I just hadn't heard that theory before. My understanding is that the drying process is to remove water, which most bacteria require to survive. This being unrelated to confiting, which is essentially a pasteurization process coupled with creating an anaerobic environment, which obviously prevents aerobic bacteria from growing. My understanding of how salt plays a role is woefully incomplete - I know that it draws moisture out, but I just don't know how big a role that plays. We are clearly not removing enough moisture from the meat to completely dry it out, which would be required to prevent bacterial growth in that manner (at least, this is all according to my rather poor understanding of the biological processes involved).

[Chris Amirault]

You can buy a tub of it from Whole foods. Its only 6 or 7 bucks...

You can? What brand? I've never seen it at our WFs.

[hansjoakim]

I'm also curious about using other fats or oils when preparing duck confit.

Michael Ruhlman has a nice recipe for duck confit using olive oil as the cooking medium: Duck Confit: It's What's For Lunch.

Now, the fat factor has me wondering: In the "Test Kitchen tip" part of the recipe for duck confit from Bon Appetit, the "simpler" olive oil confited version should be kept a maximum of 3 days under refrigeration.

Any thoughts or comments regarding the discrepancy in keeping times between the two recipes? And would making duck confit with duck fat increase keeping times under refrigeration compared to e.g. olive oil? If so, I guess this would have to do with the properties of the fat once it hardens (i.e. a more or less air tight seal)?

Thanks :)

[Mjx]

This is going to come too late to be useful now, but if you like the results of your confit, just save the fat that renders off when you cook anything with duck. I don't know whether or not the breasts I get are remarkaby fatty, but I find that from just a month's worth of duck breasts (three or four full), I get enough for a batch of confit.

[hansjoakim]

Just finished a terrific duck confit dinner (followed Ruhlman's recipe, poached the legs for roughly 8 hours, and served with pommes purée and a lentil ragu):

[sheepish]

I find British supermarkets get all excited about goose and duck fat for Christmas. And then in January they decide it's not likely to sell and discount it heavily to clear the shelves. The tinned stuff usually has a 3 or 4 year life, so I pounce when I find it. Still working my way through a dozen 500g tins bought from Tesco at 30 pence each last year.

I render quite a lot of lard, and although i haven't tried it for duck confit it's pretty neutral tasting and I imagine it would give respectable results.