So I have this idea for a flavor / beer quality experiment that involves playing with high and low efficiency. You know how "they" always say that "no-sparge brewing results in superior malty flavors" or something to that effect. I do believe this is true, but I still need to run more experiments, eventually, to confirm it. Meanwhile, I have concerns that high efficiency results in the opposite: low malty flavors, even to the point of tasting watered down.
The low efficiency test subject is best produced through no-sparge. The high end test subject likewise ain't no problem if you crush like mad -- I got 95% brewhouse efficiency on my last batch without even trying. Granted, it was only a 2-gallon batch, so I sparge more so that I can boil off more water in my standard size kettle, i.e., smaller batches lead to higher efficiency, but anyway...
I have experienced this phenomenon in at least one previous batch where I got 94% efficiency -- it was an award winning Vienna lager, but with the judges all commenting, "tastes wonderful, no flaws, except that it seems kind of watered down", and I agreed, making the same comment even before entering any competitions. We'll find out in a few more weeks when this next current batch of 95% is finished. I'm serious when I say it was on accident. I was only shooting for low 80s.
This whole topic is perhaps best introduced through reference of a good long thread from a couple of years back on the BN forum. There were heated discussions on two sides, both promising to perform experiments, but then the whole idea just kind of died for whatever reason. Maybe we can pick up again where we left off. See here: