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For my final project I built a sous-vide immersion cooker

fab.cba.mit.edu

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Re: For my final project I built a sous-vide immersion cooker

#101

Post by bradyd »

jwr wrote: post #71
abakker wrote: post #60

Earlier quoted context omitted.

because the temperatures inside are below instant pasteurization temperatures (158°F) though, reaching the target is insufficient. They need to be held at the target temperature over a period of time to guarantee sufficient pasteurization. I'll also agree that the learning process can't be beat the way you did it. I suppose you could simulate the PID function in software on the arduino though - http://playground.ardu…

Be careful with Arduino libraries. If you are trying to learn something, it's usually better to write your own, or look at really good code. Case in point, PIDLibrary, I'm looking at the PIDCompute function, line 57: ITerm+= (ki * error); That's not how you deal with I. You are supposed to accumulate (integrate) the error and multiply by Ki only for the final PID addition. You don't want to accumulate your errors mul…

That is actually done intentionally to allow for changing of the tuning parameters while the PID is running.[1] The author of the PID library has a full writeup on the design of the algorithm.[2]

[1] http://brettbeauregard.com/blog/2011/04/improving-the-beginn... [2] http://brettbeauregard.com/blog/2011/04/improving-the-beginn...

Re: For my final project I built a sous-vide immersion cooker

#102

Post by alilja »

joshu wrote: post #95
scott_karana wrote: post #35

Earlier quoted context omitted.

"Sealing in the juices" is definitely false, but a hot sear to cause the Maillaird protein reaction is important if you want to have the distinctive "traditional" steak taste.

The more important question for sous vide: Sear before or after vacuuming? Or both?

Definitely after. Cooking denatures the myosin and releases water; a seared steak soaking in water isn't going to have the kind of texture you'll get (and want!) from the Maillard reaction.

I guess what I mean is that it'll taste fine but the texture won't be quite there.

Re: For my final project I built a sous-vide immersion cooker

#103

Post by StavrosK »

I love the "cost" table. Having recently built a mobile phone out of a rotary phone (https://www.youtube.com/watch?v=fSkdWQswpc8), my costs look something like those, except:

Cost of materials: $50

Time cost: $1500

Then again, it is a prototype, which has to go with all the fixed costs, but to say that this cooker only cost $X isn't entirely accurate.

Re: For my final project I built a sous-vide immersion cooker

#105

Post by bradyd »

abakker wrote: post #60
arbesfeld wrote: post #57

Earlier quoted context omitted.

Great points, I do think that a professional PID is a better and more efficient way to build a sous-vide. I wanted to build something from basic components instead as part of the learning process, and also to allow me customize the logic via Bluetooth. Regarding the steak, I find that a 1 inch thick steak only takes ~45 minutes to reach the target internal temperature. This scales dramatically as the steak thickness…

because the temperatures inside are below instant pasteurization temperatures (158°F) though, reaching the target is insufficient. They need to be held at the target temperature over a period of time to guarantee sufficient pasteurization. I'll also agree that the learning process can't be beat the way you did it. I suppose you could simulate the PID function in software on the arduino though - http://playground.ardu…

There is a tutorial on Adafruit[1] that makes use of that library to build a sous-vide cooker using a rice cooker or crockpot. I built one a little over a year ago. It was a great learning exercise. The real issue with it is that (at least with my setup) it takes forever to preheat (~1 hour to get to 130°F). I speed this up using boiling water. At higher temperatures (170°F+) it still takes a long time to heat, even with this method. I also use a pump to improve the temperature consistency, which is not mentioned in the tutorial. I recently got an Anova Immersion Circulator, which is much easier to use.

[1] https://learn.adafruit.com/sous-vide-powered-by-arduino-the-...

Re: For my final project I built a sous-vide immersion cooker

#106

Post by stephen_g »

ha292 wrote: post #89

Question for sous-vide aficianados. Are you not worried about the chemicals going from plastic to your feed ? I grew up knowing that, by and large, the less manufactured stuff you put in your food the better the food is for your body. So, it seems highly dangerous to me to take natural piece of food, wrap it in a highly complex chemical compound (plastic), heat it, and then consume it.

You can safely microwave food in certain types of plastic - sous-vide cooking is far lower temperature.

But the initial premise is unfounded. Some of the most toxic chemicals occur naturally.

Re: For my final project I built a sous-vide immersion cooker

#107

Post by pbhjpbhj »

bliker wrote: post #104

I was wondering why there is a need to involve a micro-controller? I can see this project being done with couple of op-amps and potentiometer? I see so many hobby project using arduinos for no good reason. Please people show some love for analog electronics!

>why there is a need to involve a micro-controller? //

Easiest way to implement bluetooth?

Re: For my final project I built a sous-vide immersion cooker

#108

Post by stephen_g »

gitpusher wrote: post #55

Great project, and great write-up. But most people don't have access to a 3D printer... which significantly changes the effective "cost" for such folks. Still, thanks for sharing! Hope you enjoy all of that perfectly-cooked food :)

What's to stop somebody putting it in a $5 pre-made plastic box that you can find at any electronics store?

Re: For my final project I built a sous-vide immersion cooker

#109

Post by ajcarpy2005 »

bliker wrote: post #104

I was wondering why there is a need to involve a micro-controller? I can see this project being done with couple of op-amps and potentiometer? I see so many hobby project using arduinos for no good reason. Please people show some love for analog electronics!

Bluetooth controller
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