On the bge?

[ike456]

i know sous vide means something like "water bath". But, I was wondering why cant I have my grill set at 135 and put my steak on it instead of using a sous vide?

[MBMorgan]

You could ... but you'd need a long ... long ... long time. You'd also put yourself at risk of food poisoning as a result of holding the steak in the "danger zone" for so long. Sous vide cooks via conduction vs. convection when cooked indirect in your BGE ... and conduction is MUCH more efficient than convection.

[EdF]

But there's always the hot water in the beer cooler trick, which will give you an idea as to whether sous vide style cooking belongs in your quiver.

[morganjim]

If you could hold the steak in the hot water bath on the grill you'd be ok. Then again, you'd just be doing the sous vide on the grill rather than inside.

[Potkettleblack]

Fun experiment. Don't try at home.
Set your oven for 250. Put a pan in. Leave it for half an hour.

Now, the difference between air cooking (like the BGE) and water cooking (like sous vide) is the difference between holding your hand in that oven and holding the pan. You could hold your hand in a 250 oven for a long time. You wouldn't want to touch that pan handle at 250. For a safer experiment that you can do at home, heat your oven the same, then turn your kitchen sink faucet as hot as it will go. No problem in the oven at 250, but you get a reasonable hotness from 130-140* tap water.

Water transfers the heat a lot better than air.

135* air won't do much cooking, even at sous vide length time. And it taking something from room temp or fridge temp up to target temp, it will spend an inordinate amount of time in the bacterial growth danger zone.

Mono, you can't sous vide on a BGE.

[morganjim]

I doubt that there is any difference between a pan of 135 water on a grill or a pan of 135 water with a sous vide element in it.

[Potkettleblack]

No. But OP wasn't asking that. And I'd suspect holding a BGE at 135 precisely is a lot more difficult than holding an Anova at that temp.

[morganjim]

Potkettleblack No doubt.

[Breadhead]

Hmmm... I have both a large BGE and a couple of Anova circulators. I don't sous vide in the BGE and I don't BBQ in the SV bath tub.

I do sous vide first and then sear it on my grill though.👍

[josht138]

MBMorgan sous vide cooking is still cooking by convection especially when you use a circulator. It's really no different than cooking in an oven. For more on convection see meatheads article here: http://amazingribs.com/tips_and_tech...f_cooking.html. Also see the food labs article too which explains this a bit better: http://www.seriouseats.com/2015/09/t...mperature.html.

The reason why sous vide is more efficient is the convective heat transfer coefficient of water is higher than air especially when you are "forcing" the convection with a circulator. As the velocity of the fluid increases so does the heat transfer coefficient.

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[MarkinJHawkland]

I'm confused about sous vide too. Can someone tell me why the food is held in the bath for so long? I understand that conduction is more efficient. But that fact would seem to make sous vide work faster. I see posts where people hold their product for days!?!?

[Potkettleblack]

Please see my post above. Lower temps cause longer cook times, especially when you need to break down connective tissue.

[MBMorgan]

MBMorgan sous vide cooking is still cooking by convection especially when you use a circulator. It's really no different than cooking in an oven. For more on convection see meatheads article here: http://amazingribs.com/tips_and_tech...f_cooking.html. Also see the food labs article too which explains this a bit better: http://www.seriouseats.com/2015/09/t...mperature.html.

The reason why sous vide is more efficient is the convective heat transfer coefficient of water is higher than air especially when you are "forcing" the convection with a circulator. As the velocity of the fluid increases so does the heat transfer coefficient.

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Sorry josht138 but you've got it backward. The food in a sous vide bath is effectively in direct contact with hot water. Heat is conducted directly into the food from the water. The circulator is mechanically "stirring" the water to keep the heat distributed evenly throughout the bath ... nothing to do with convection.

[josht138]

Nope MBMorgan Water and air are both fluids, they just have significantly different densities (about 62 lb/ft^3 vs. 0.24 lb/ft^3) . The same way that the food is in direct contact with air in an oven, it is contact with water in sous vide (with the exception of the plastic bag which is likely negligble) . The conduction that occurs during sous vide is from the heat source and then the meat or protein cooks itself from the outside in through conduction. The water is the fluid medium in between.

Conduction is heat transfer between two solid bodies and convection is heat transfer between two solid bodies using fluid or a gas as a medium.

[josht138]

Let me clarify one more thing. There is both conduction and convection but I still maintain that cooking in sous vide with water vs bbq with air or in an oven are the same methods of transferring heat.

The only way you could only have conduction when cooking with a fluid is to cook in equilibrium which is next to impossible since you always have an ambient temperature that is below your cooking temperature. As ambient temperature is always going to be below your cooking temperature you will always have some fluid movement which is natural convection. When you introduce a fan like a convection oven or a sous vide circulator you create forced convection which causes your convective heat transfer coefficient to increase and will speed up your cooking time or make it more effective.

Both water and air have thermal and conductive heat transfer properties. In both cases water is better at transferring heat.

[MBMorgan]

Let me clarify one more thing. There is both conduction and convection. The only way you could only have conduction when cooking with a fluid is to cook in equilibrium which is next to impossible since you always have an ambient temperature that is below your cooking temperature. As ambient temperature is always going to be below your cooking temperature you will always have some fluid movement which is natural convection. When you introduce a fan like a convection oven or a sous vide circulator you create forced convection which causes your convective heat transfer coefficient to increase and will speed up your cooking time.

Uh ... thanks for the info ... but you're talking to a research geophysicist here who harbors a slightly different definition of convection than an engineer might (checked your profile ).

Edit: Just thought of a great compromise involving the solid barrier between hot water and the food ... remember the bag? The bag (heated by convection) conducts the heat to the food.

[josht138]

MBMorgan Fair enough. I edited my post above before you replied where I still believe that sous vide and cooking in air are the same. However I really hadn't been thinking about the bag. We thinking about the bag, I do agree that it conducts heat. In addition the bag should remove the evaporative cooling effect that would slow the cooking process from convective heat transfer. If anything wrapping the meat in foil vs cooking sous vide in a plastic bag should be the same thing with just different heat transfer properties ie., water vs air, plastic vs aluminum / butcher paper.

And yes I'm a mechanical engineer but my speciality is not heat transfer so while I understand it and studied it, I'm by no means claiming to be an expert on it or docblonder .