(1) Good efficiency combined with good technique doesn't result in lower quality worts, true.DaaB wrote:It's not good efficiency that is directly reponsible for producing poor quality wort although when fly/continuous sparging to get maximum efficiency it is necessary to extract as much sugar as possible which requires rinsing every last drop of sugar out of the mash. Unfortunately as the sugar content drops the ph rises sharply and the combination of a ph of 6 (some say 7) or more and hot water can extract tannins and phenols which reduce the quality of the wort causing astringency and can produce a haze.
If you batch sparge the ph of the runnings remains constant throughout each batch therefore there isn't a significant risk of oversparging.
(2) Pursuing very high efficiency can lead to lower quality worts, particularly when combined with bad technique giving inefficient extraction of sugars causing the brewer to pile more and more liquor through until eventually the sugars are dragged out - along with tannins, phenols, husk flavours, etc, so on paper the efficiency looks ok, but the wort isn't!
(3) Low efficiency through bad technique can also result in lower quality, as again, most of the good stuff is being left behind, and what is being got is mostly liquor with a bit of sugar extracted from the channels through which it flowed.
(4) Low efficiency combined with good technique will give higher quality wort, because the good stuff is being extracted, and the dross left behind. Using a larger than technically needed batch of malt means you can get the best of the malt without needing to extract to the point where the dodgy stuff starts to come out.
Historically brewers felt that the best worts came from the first mashing and that worts from the 2nd and subsequent mashes of the same batch, apart from being weaker, were also inferior in quality. 'Somehow, the second wort doesn't have the sweetness that its gravity would suggest'.
Recently a group of us brewed a parti-gyle beer to the same recipe. One at OG1100 and a second mash at OG1061. Everyone apart from me did a historical double mash. I didn't - I didn't have the time or the gear. What I did was brew the OG1100 beer, and then dilute a portion of it down to OG1061 - a modern parti-gyle. Come the tasting, the double mashed 1061 beers all had a similar quality to them - a bit of harshness and somewhat un-integrated. Mine compared very favourably, being cleaner, smoother, and more approachable.
Did that have anything to do with the fact that is was a dilution of the high quality first wort, and not from a lower quality second wort? Not necessarily, but definitely possibly maybe
