from Hacker News

Cook My Meat: heat diffusion through meat over time

by tomkinstinch on 12/17/18, 11:48 AM with 66 comments

• by cityiguana on 12/18/18, 1:56 AM

  I'm one of the 3 MIT students (now MIT alumnae) who coded this over 5 years ago now. It's popped up around the Internet again in the past year or so, which is neat but also a little cringey, because it forces me to look at code I wrote when I was a lot newer to programming than I am now.

  One person commented about a better simulator that they'd developed, which I am certain exists. This simulator was developed for an EdX class called the Science of Cooking. Although we tested it and found it to be largely accurate (in one of the more delicious code testing sessions I've ever attended), it was designed primarily to illustrate the various reactions that occur at the molecular level, rather than to provide actual cooking guidance.

  Also, it seems that some of you are having problems where the program crashes your browser. Unfortunately, that's not entirely avoidable as the whole application is client-side javascript, and does some moderately complex calculations for heat diffusion. Obviously this would not be the approach I would take if I were to rewrite the program today...

  If anyone wants to take a look at the source code, here is the original git repo: https://github.com/laurabreiman/science-of-cooking. Cheers everyone!

• by compumike on 12/17/18, 8:38 PM

  We built a somewhat better thermodynamic model into the Pantelligent iOS and Android apps -- i.e. user would select 1" thick steak, medium, and then we'd use the real temperature signal to adjust the cooking time.

  The key fact this simulation is missing is that the outermost layer of the food quickly becomes dehydrated, at which point its thermal conductivity drops dramatically. This is good! It allows for much more uniform internal temperatures.

  Edit: we did a lot of thermal simulation using my CircuitLab simulation engine (https://www.circuitlab.com/) -- circuit models for thermal simulation are common, where voltage represents temperature, and current represents heat flow. The simulation engine allows for arbitrary behavioral elements like algebraically-defined resistors, which lets you model this "outer layer dries out" behavior quickly.

• by thinkingkong on 12/17/18, 9:14 PM

  I'm impressed but disappointed the "reverse sear" is missing. If you haven't tried, it, it's a pretty amazing way to cook a steak and it scales up to lots of steaks at the same time.

  It's awesome

  [1] https://www.seriouseats.com/2017/03/how-to-reverse-sear-best...

• by dekhn on 12/17/18, 9:43 PM

  Once, Nathan Myhrvold spoke at Google about Modernist Cuisine and I asked him how to make the ultimate BBQ ribs (he won some competition). He said "sous vide, liquid nitrogen, then deep fry". Glad to see this site includes sous vide + liquid nitrogen.

• by wiz21c on 12/18/18, 8:55 AM

  Cooking the meat is cool. But, being someone of french gastronomical culture, I to to lean to Fernand Point saying : "Du beurre ! Donnez-moi du beurre ! Toujours du beurre !"

  (basically, butter, butter, butter).

  There was a recipe from G. Ramsay where it show to first sear the steak in oil, then, finish it with a bit of butter. It adds flavor and prevent the butter to burn.

  I also tend to use my finger to test if a steak is fine. I'm no expert, but it works 80% of the time (to get a good steak). Now I must admit that sous-vide gives a lot more control and helps to reach the medium cook on a much wider part of the meat.

• by dunham on 12/17/18, 9:48 PM

  It's not clear to me what they're using for the surface heat transfer coefficient, which I think would be different for a skillet vs sous vide. (Or even, in their case, Side 1 = skillet vs side 2 = air.) But I only have a cursory knowledge of the physics involved.

  For the sous vide case, I've tried implementing Douglas Baldwin's model on Observable. It seems to match the "SousVideDash" results, but this is my first foray into solving PDEs, so use with caution.

  https://beta.observablehq.com/@dunhamsteve/sous-vide-calcula...

  If anyone here does know the physics / math, I'd like more details on the $\beta$ "geometric factor" that Baldwin uses. I couldn't find mention of it in books and wonder if it is something you derive (say transforming coordinate systems) or something determined experimentally.

• by MobileVet on 12/17/18, 8:23 PM

  My go to site when cooking thicker than normal steaks via Sous-vide

• by bigbadgoose on 12/17/18, 10:39 PM

  This model needs density, moisture content, and temperature gradient at initial cook.

  Prob a second model for bone-in cuts.

• by hammock on 12/17/18, 9:43 PM

  I'm looking for a recipe that maximizes the term Net Meat Score = [(browning+med rare) - (medium+well)] while also enforcing steak=3cm, Rare=0%, Raw=0, Char=0, and steak starting at either 0C or 23C. Note that you have to let the meat rest for 10+ minutes to really let it finish (the default settings cut it off to early).

  The best I have gotten under normal conditions is: Net Meat Score of 40, by doing:

  Steak starts at 0C, 3:20 @190C , flip, 1:40 @190C. Yields 17% brown, 23% well, 7% medium and 53% med rare.

  Chose 190C because olive oil. Interested if anyone has found something better.

• by bcheung on 12/18/18, 3:02 AM

  Would be interesting to see sous vide and torches incorporated into this.

  I usually "sous vide" at a lower temp and then finish with a weed burning torch (aka flame thrower). I find using a large and very hot flame is necessary to get that crisp outside without overcooking it. The handheld chef torches don't get enough searing to cooking ratio.

  Fat and connective tissue is another factor that makes things interesting. What's the best technique to soften up the fat and connective tissue without denaturing the protein?

• by person_of_color on 12/17/18, 10:16 PM

  My question is how to brown/caramelize meat with only an induction cooktop?

  After I put my chicken, I just see all the water come out and the chicken starts boiling in the pan :(

• by sigmar on 12/17/18, 9:37 PM

  It breaks when you switch to Fahrenheit and use the sous vide + liquid nitrogen recipe. It autoconverts -200°C to -328°F which then errors "too low" (for some reason?)

• by httpz on 12/19/18, 5:05 AM

  Does this work for sous vide and reverse sear? Water's thermal conductivity is 1/10th of iron and much smaller for air(oven).

• by yunzo on 12/17/18, 9:26 PM

  If you put a thick steak (like 50 cm) it freezes Firefox for like 4 seconds, while Chrome freezes for 1 second. Real world benchmarks :D