FlyGuy
Well-Known Member
So has anyone read Steve Holle's article on batch vs. fly sparging yet? I was hoping for a good read, but ended up confused in the end. Personally, I was disappointed in the article because it wasn't terribly informative, and the comparison of techniques is rather shallow and one-sided. There have been far better discussions here in the past (and there is no point in reliving those same arguments again!).
Anyways, throughout the article Holle seems to argue that while batch sparging is 'reputed' to be an easier method, it is inherently inefficient and necessarily produces lower quality wort. While the extent of these differences in 'efficiencies' or 'qualities' is never actually addressed, it is implied that it is substantive (at least that was my read of the article).
If you have read the article, what are your thoughts? I believe there were a few flaws in reasoning. First, Holle explains that batch sparging is possibly better at avoiding off-flavours from tannins extracted while lautering (but only because batch sparging is such a darn inefficient method). But then he goes on to say that tannin extraction in batch sparging is actually highly problematic (and this is the main thesis of the article) because during the sparging process, the wort is entirely drained from the grainbed exposing it to air. He also claims that this will oxidize tannins in the exposed grains, thereby leading to low quality wort.
He never really explains why fly sparging produces higher quality wort, except to imply that oxidation of the mash is not a problem. However, even though he mentions that the common way for homebrewers to fly sparge is to continuously sprinkle hot water on to the grainbed. This exposes the sparge water to air (and thus, of course, oxygen), but that discussion is omitted. He also fails to remember that he previously stated that tannin extraction wasn't an issue with batch sparging, confusing me as to why it would ever be a concern in the first place (oxidation or no oxidation).
At the end of the article, he goes on to relate a hybrid technique from Germany where batches of sparge water are added to the mash, stirred, then drained, but the wort is never drained enough to expose the grainbed before the next batch of sparge water is added. He seems to be advocating it as an improved method of batch sparging, but for a homebrewer, I am not so sure how useful this technique would be (it sounds like the most difficult parts of the two sparging methods combined).
What I did take from the article was that there is a POSSIBILITY that the batch sparging technique could lead to problems with oxidation of tannins. Unfortunately, the extent to which this does or does not occur was not explored by Holle (he just assumes it is always problematic). The experience of homebrewers that have successfully moved from fly to batch sparging probably suggests that the extent of this problem is negligible.
But, it did get me wondering if batch spargers should be paying extra attention to tannin extraction, particularly when they are shooting for high efficiencies (say in the mid-80's and above) where tannin extraction does become a real possibility. I suspect that it is only at these high efficiencies where tannin extraction occurs and the effects of oxidation begin to rear its ugly head.
Shoot -- that's longer than I intended. I'll shut my trap now.
Anyways, throughout the article Holle seems to argue that while batch sparging is 'reputed' to be an easier method, it is inherently inefficient and necessarily produces lower quality wort. While the extent of these differences in 'efficiencies' or 'qualities' is never actually addressed, it is implied that it is substantive (at least that was my read of the article).
If you have read the article, what are your thoughts? I believe there were a few flaws in reasoning. First, Holle explains that batch sparging is possibly better at avoiding off-flavours from tannins extracted while lautering (but only because batch sparging is such a darn inefficient method). But then he goes on to say that tannin extraction in batch sparging is actually highly problematic (and this is the main thesis of the article) because during the sparging process, the wort is entirely drained from the grainbed exposing it to air. He also claims that this will oxidize tannins in the exposed grains, thereby leading to low quality wort.
He never really explains why fly sparging produces higher quality wort, except to imply that oxidation of the mash is not a problem. However, even though he mentions that the common way for homebrewers to fly sparge is to continuously sprinkle hot water on to the grainbed. This exposes the sparge water to air (and thus, of course, oxygen), but that discussion is omitted. He also fails to remember that he previously stated that tannin extraction wasn't an issue with batch sparging, confusing me as to why it would ever be a concern in the first place (oxidation or no oxidation).
At the end of the article, he goes on to relate a hybrid technique from Germany where batches of sparge water are added to the mash, stirred, then drained, but the wort is never drained enough to expose the grainbed before the next batch of sparge water is added. He seems to be advocating it as an improved method of batch sparging, but for a homebrewer, I am not so sure how useful this technique would be (it sounds like the most difficult parts of the two sparging methods combined).
What I did take from the article was that there is a POSSIBILITY that the batch sparging technique could lead to problems with oxidation of tannins. Unfortunately, the extent to which this does or does not occur was not explored by Holle (he just assumes it is always problematic). The experience of homebrewers that have successfully moved from fly to batch sparging probably suggests that the extent of this problem is negligible.
But, it did get me wondering if batch spargers should be paying extra attention to tannin extraction, particularly when they are shooting for high efficiencies (say in the mid-80's and above) where tannin extraction does become a real possibility. I suspect that it is only at these high efficiencies where tannin extraction occurs and the effects of oxidation begin to rear its ugly head.
Shoot -- that's longer than I intended. I'll shut my trap now.