augiedoggy
Well-Known Member
Do you really not see the downside ? you mention circulation as being a key apsect of this system but with a basket basically holding a ball of grain in the middle with an opening between it and the pot completely around it for the wort to easily bypass it you do not get very effective recirculation THROUGH the grainbed instead of around it.It seems maybe a bit late to jump in, but I didn't see this thread earlier so here goes!
My 2 cents...
The reason you are pumping wort, is for optimum temperature control. It moves the wort around the vessel. Because of this exchange of wort, the PID can react faster therefore keeping temps with greater precision. As a result, you do have a clearer wort because of circulation, a small bonus. Building a grain bed in BIAB is not relevant like it is in a traditional mash tun so issues of whether there are holes in the sides of the basket aren't issues as you are brewing with a full volume of wort. The grains are more immersed like a tea bag is in tea. The basket is there for protection from the element and yes, for lifting but I'm still trying to find a downside to the basket vs. just the bag.
I think the system will make beer just fine, its just not an optimized setup and the beer could come out with much more consistent efficiencies if the basket (or bag ) filled the whole circumference of the pot, forcing the wort to travel through the grains and not around them as is more likely to happen with a basket. the pid and recirculation will help keep mash temp once its reached at dough in (if correct like Alpha mentioned) but its acting more like a waterjacket around a conical really than actually recirculating.
Obliviously the system works and people are happy with it but are the results really that consistent? does the wort really stay clear for those who raise the basket and sparge through it? that would be one indication of how well its actually recirculating It does with the setup I use.
Put it this way if you wanted to make an effective filter such as a carbon filter for water to pass through. Would you fill the whole opening with carbon forcing an even path of resistance through the filter or would you put a smaller basket of media in the center of the water pathway?
which do you think would be more efficient? Which would you use if you had the choice? sure they would both work to a degree but one would be vastly superior. Not exactly the same thing but the same causes and effect would apply.
I'm not being bias about anything because I honestly didnt pay attention to the differences and which system is which except the high gravity setup which I know from other threads. I'm just trying to keep this about the technology and the engineering involved here and it weaknesses... afterall we are constantly learning and improving here from what I've seen.