Decoction in BIAG?

[Arbe0]

I made an Electric brew RIM system pot that does smaller batches . this would be a BIAB that has heated water always running though the grains.
Most BIAB mash profiles only call for saccharficaton and a Mash out. What do you think about using a profile like a Decocation that has several temperatures (usually 3)
with an electric system I can raise the temperature as I like for a set amount of time.
what do you think?

 

[Arbe0]

with this system I wouldn't be taking out grains and boiling them, just raising the temperature

 

[GernBlanston]

It would work, but technically it would be a ramp up. Which, if you pause at the various necessary temps, will give you the effect of a step mash, but not what a decoction will do.
Boiling a thick portion of the mash with as little liquid as possible on a separate burner, will give you a cooked, melinoidan flavor that a step mash ( adding boiling water to raise temps) or a ramp mash (simply heating the mash, by direct heat or with a RIMs/ HERMs recirculation), can't do.
If all you want is the various possible rests (Acid, beta-glucan, protein, sacrification), then a step/ ramp mash is perfect, and I would say in your case with a RIMs system, it would be Ideal.
However if you want an authentic decoction for a Czech Pilsner, German Pils or Marzen, then boiling a thick mash is the only way.

 

[Ozarks Mountain Brewery]

I recirculate with a rims set up but in a larger volume , i can brew 20 gallons at a time if needed and in the past experimented with step mashing while recirculating. i just added the steps in the recipe editor to up the temp after so may minutes, it worked fine but I did not do a second or 3rd decoction, but could after draining the mash then adding water back and recirculating again then draining, problem is my system drains the sugars very well meaning the second runnings would be very weak