Reductones issue in RIMS?

General Homebrew Discussion
1

Mastering homebrew, The Brewing Process pg 148
  … " Modern brewing science has come to the realization that the intense heating of wort that you get from a flame under a thin vessel of stainless steel is bad for beer.  The problem is the formation of reductones, certain chemicals that can latch on to and then release oxygen.  So, most homebrewers have a problem because of our direct-fired stainless-steel kettles.  The problem isn’t the metal itself; its the fact that stainless steel is a very poor heat conductor, so heat applied to one area tends to stay there and become quite hot, rather than spreading out at a more moderate temperature.  In fact, the heat at this boundary layer may be far higher than desirable.  If you can see the pattern of the burner after you’ve emptied your kettle, it’s too hot.  If you have black char, you really have big trouble." …

So the question in there is that going to be a problem when designing a Brew in a basket “brew boss” like system?  A 5500W heating element in a 15G kettle going to cause problems.  From what I can only imagine a direct fire 302 stainless steel heating element would cause much of the same issues and caramelization off flavors as a thin crappy stainless steel pot. Or is that a non-issue?

2

Sounds like a question for the physics/chemistry guys - of which I am neither.  I do believe that the constant movement of the wort past the heating element is crucial here - you don’t want to scorch it by leaving it in contact with the heat source in either event, but in a boil kettle, the wort should move by thermal dynamics to some degree.  Will it scorch before moving?  I don’t know that science.  Will it produce an off flavor?  Perhaps the reductone issue is significant with either process, but I have tasted scorched beers made commercially on an electric kettle, so I know it can happen there.

3

I think the problem with direct fire is that due to the amount of heat and the type of metal, the energy does not dissipate quickly. It’s all about the energy transfer per surface area.  If you have ULWD elements it shouldn’t be an issue.

4

5500 might be overpowered for a boil kettle setup depending on watt density. I’d select the largest element I could with the lowest watt density available.

5

Or use two lower density ones.

6

No, you definitely want the full 5500w in that kettle. You moderate the actual wattage delivery via a pulse width modulator, so there isn’t any real possibility of overheating the wort at the element contact. The bottom line is that the surface of the element can’t get much hotter than the boiling point since wort convection currents will tend to move the heat away into the wort and off into the kettle.

Having a lot of wattage means that you’ll be able to get the wort up to boiling quicker. You will likely have to reduce the power, once boiling.

7

Ah, PWM will reduce the energy density! Nice.

8

Would high gravity’s EBC-SV 240V with a NEMA 14-30R connection, an analog PID controller work?

http://www.highgravitybrew.com/store/pc/EBC-SV-with-Infinite-Power-Control-272p3986.htm

It is more expensive than I was hoping.  However that is a lot of power to try and DIY electric controller, and I am no electrician.

9

High Gravity’s controller send PWM power to the element(s), yes.

From personal experience using their EBC-III as the controller for their BIAB setup, make sure you get a ULWD element, or a BLichmann element. My setup only had  LWD element and I scorched a batch of beer once.

10

Sure, the High Gravity unit will work. If you are handy enough with electrical, the DSPR1 unit from Auber is very good. I’ve used one for years.

11

That controller wouldn’t control temp for his RIMS. Auber did recently release a new controller that is a bit of a hybrid.

12

Correct, for a true 3-vessel RIMS setup you’d want the EBC-III.

But for BIAB the EBC-SV will work just fine, it just has the pump circulate the work constantly.

13

I was speaking of the Auber controllers.

If the elements were to be used for just boil or hot liquor, I’d opt for the highest I can support while still using the lowest density available at that wattage. For a BIAB style RIMS setup or Kettle RIMS setup, I would go with the 4500 watt ULWD and just deal with the extra time to heat. This is assuming 10-20 gallon kettles, larger would certainly make me consider a 5500 watt element and possibly a separate 110v heat stick style element for extra boost.