No, where I was coming from was this: people used to claim that batch sparging couldn't be as efficient as fly sparging. Since then, a bunch of other people proved them wrong. It turns out that the statement (still falsely believed by many people) was based on assumptions about how to batch sparge using fly sparge equipment and fly sparge techniques. In reality, batch spargers with efficient system can get HIGHER efficiencies than many fly spargers because they have an easier time limiting losses in the MLT, they can often crush finer because they don't worry about channelization or stuck mash, etc.
I am curious if people are exceeding the 'theoretical' limits on extraction efficiency because the underlying 'theory' is flawed. It would be interesting to know where the errors occur.
Oh, I also looked at the links you provided, but I am confused by what it is you want to correct me on. The figures you cite in those links all refer to efficiencies for fly sparged brews, not the typical extraction efficiencies for the no-sparge technique.
I'm glad we have had this back and forth. I did not get what you were saying in your original post and now I do (well maybe, my track record here is not too good). I would rather not have irritated you or whatever to get here, but that's one of the problems with this kind of communication, misunderstandings grow until corrected.
The 65% number stuck in my mind, i overlooked the no sparge part.
Which is ironic, i let my preconceptions interfere with my reading of your comments...
I'm here to learn and enjoy doing it. After thinking about your question more, here is what comes to mind - BIAB is technically no sparge, but to me it seems different, but I don't know why is seems different, it just does.
When you look at the 2 techniques they are almost identical. The obvious differences I see are the grind on the grains and the lautering. Maybe finer grind allows the sugar to come out into the liquid more easily (but not all biabers grind small)? I wonder if suspending or "collandering" the bag and letting it drain is somehow different than "opening the spout" or whatever no spargers do to get their liquor. Is there additional pressure in the bag that helps recover more liquid or somehow push sugar out of the grain? Does the zero dead space make that much difference? Many BIABers hang the bag and let it drip, does this recover more liquid and squeeze out a bit more sugar? I have read some brewers physically squeeze the bag (twisting, pressing sides, etc), does that get much extra sugar out? Does the shape of the grain blob matter somehow, cylinder vs. teardrop? I doubt any of this would have much of an impact on efficiency. But something is going on as many folks are doing some pretty efficient brewing. (I know some of things I mention above would effect brewhouse more than extract efficiency, but all too often folks just say efficiency, so it is hard to know what they mean, so I just threw some ideas out that might effect either. )
Anyhow, no hard feelings and I'm done here, I fear I may have killed a pretty good thread... I have to go attend to a belgian tripel that just blew the airlock, should have known better and hooked up a blow off tube. brew on.
and got a 5 gallon paint strainer bag, the bag fits into the coolerand am able to pull it over the threads. preheat the the cooler and then add 3 gallons mash water to the grains in the bag in the cooler at about 162 stir and i get 150 mash temp droping 2 degrees in 90 minute mash. because the bag is streched over the coller threads the top holds the bag in place and am able to shake the cooler to stir the grains without removing the lid. while masing i heat my 3.5 gallons of sparge water to 180 degrees in the boil pot, when the mash is done i pull the bag and sit it in the a callander over the cooler and squeze the bag and then the bag goes into the sparge water in the pot for 15 minutes. 180 gets me 170 sparge temp. I have my stove down to where to know where to set the dial to maintain 170. after the 15 minute dip sparge i once again put the bag in a coolander over the pot. turn the heat up. squeeze the bag then remove to go in the garden. I add the mash from the cooler. usually do a 60 minute boil. i am usually several ponts over the origianl gravity called out in the recipee and have gotten final gravities 1.010 or lower for recipees that call for brewhouse efficiencies of 75 percent. this is working well for me and have done 7 to 12 pounds of grain, i think 12 would be about max for my 5 gallon cooler.
