Why sous vide?

BTW, here’s an interesting comment from Chris Young today on Reddit. Obviously the best of all worlds would be to have the Combustion Predictive Thermometer talk to the Joule Turbo (or a combi oven like the Anova). He’s apparently talking to people, but no ideal what appliance(s) he’s trying to integrate with. I would assume an oven. Maybe the Ninja he recently reviewed and liked. Or something in the BBQ world would make sense, since BBQers are predisposed to think about things like the “stall”.

"In the case of bagged sous vide, early in the cooking the surface temperature is often 5 to 8C cooler than the surrounding water. This is because heat is flowing towards the core a bit faster than it can be replenished by the surrounding water.

In the case of air, the surface might be 50C cooler than the air.

In either case, the maximum cooking speed, with zero overcooking, is achieved by raising the surrounding fluid temperature as hot as possible without causing the surface temperature of the food to exceed the target doneness temperature. But it is important to recognize this temperature will change as cooking progress and the food warms up, which is why you need to keep turning down the temperature of the surrounding fluid to hold the surface temperature constant.

This is the idea behind Joule’s Turbo algorithm, but it has to infer the surface temperature, which is why it asks for things like weight and thickness.

With the Combustion Predictive Thermometer you can just measure the surface temperature directly and adjust the surrounding temperature as needed to keep the surface temperature steady."

Chris, this is intriguing. I can see the logic. I’d be curious about the actual science of what’s going on there. For example, I can see that because the meat is so cold, it may not be possible to crank the heat on the sous vide enough to actually get the temp needed at the surface to kill exterior nasties. I suppose same would be true for reverse sear.

That said, I’ve done sous vide cooking now for 12 years (where does the time go?!?!?!?) and have yet to have a food safety issue. Cleanliness in prep, understanding (and generally following) pasteurization tables, and of course searing meat at the end goes a long ways there (as I’m sure you all know). Though I have done plenty of sous vide seafood dishes that were way below pasteurization point and with no sear, no issues there either (though, as I grow older and less risk-averse, I’m much less inclined to do those sorts of things for anyone other than my wife and I).

Kevin, can you point me to a recipe? I’m intrigued by this one.

@Jason - Don’t read too much into my methods. It’s more of a, ‘hey, why not’ situation of killing several birds (that may not exist) with one maneuver as opposed to a serious food safety thought. Like you, I’ve been SV’ing for a dozen or more years and plenty of lower temp cooks and never a hint of food safety problems. So, this is at best another level of insurance that is likely not needed for food safety. Here’s my typical situation:

Double cut 2" bones in pork rib chops that were seasoned (which included salt of course), chamber vacuum sealed and frozen. I want a decent amount of time at 140’ish for the full thickness. So, I drop it in frozen around say 155 for 15-20 minutes to start with the thought of getting the heat moving as fast as possible and the side thought that just a minute or so of the surface being at 145 will kill any remaining badness. After that, I drop it down to 140 and let it coast to that point for a couple of hours or more. After reading on here now, I could probably start at an even higher temp and I’m not sure my surface ever achieves that 145 killing temp anyway.

BTW - It looks like the old Joule app will migrate over to the new one soon based on it being greyed out in the app store and comments by the developers. Many of the new features will be available it appears.

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According to Baldwin (link below), no pathogenic organisms of relevance to food safety can survive and proliferate at >126.1°F. However, 130-131°F is more commonly used as a lowest safe temp for sous vide cooking since pasteurization happens much faster at that temp, as described in Baldwin’s tables (note, the spores of spore-forming bacteria like C. botulinum can’t be destroyed at sous vide temps, but botulism is not a risk of sous vide cooking, it is caused by improper food storage).

There are bacteria than can grow at higher temps, but slowly. Although they are not dangerous, they can result in a unappetizing stinky aroma if you cook for >6 hr as <138°F. But this is very hit or miss and most often shows up in 24-48h cooks of tough cuts like short ribs. In that case, boiling the bag briefly before sous vide can eliminate the chance of it occuring (or less effectively pre-searing). I do short ribs at 158°F, so it’s not an issue.


For those unfamiliar, Baldwin’s guide is a wonderful reference and should be required reading for anyone using sous vide.


Complete tangent, but you never know….

Bro in law with a heart transplant can Sous vide pasteurize foods and still enjoy things not cooked to death.

There are online pasteurization protocols for this!



Baldwin’s guide, which I referenced above, covers pasteurization tables as well. As the guide covers, pasteurization isn’t about reaching a particular temperature, it’s about understanding the relationship between time, temperature, and the thickness of the protein in question.

To me, understanding those variables is critical not just for pasteurization, but for understanding how to find success with sous vide in general.