[denny]

It may seem logical, but if my personal experience directly contradicts it, guess which I'm gonna go with?     And I never automatically assume that everything that applies to commercial brewers necessarily applies to homebrewers.

[morticaixavier]

David Miller's logic seems rational enough.  Let's look at Budweiser for a moment.  Budweiser's fermentation vessels, are rigged with a level at the top that catches all the fermentation scum, that is up and kicked-out during primary fermentation. The brew master at So. Cal Budweiser say's, the purpose of the top level inside their fermentation vessels is to catch all the harsh, astringent material that would other wise affect the flavor of the finished beer.  This may suggest, that skimming the foam in the kettle along with the coagulated hot-break would lessen the harsh flavor contributions.   

Yes but that is during fermentation not the boil.

[narvin]

David Miller's logic seems rational enough.  Let's look at Budweiser for a moment.  Budweiser's fermentation vessels, are rigged with a level at the top that catches all the fermentation scum, that is up and kicked-out during primary fermentation. The brew master at So. Cal Budweiser say's, the purpose of the top level inside their fermentation vessels is to catch all the harsh, astringent material that would other wise affect the flavor of the finished beer.  This may suggest, that skimming the foam in the kettle along with the coagulated hot-break would lessen the harsh flavor contributions.   

Skimming the braun hefe during fermentation is a different topic, really.  In this case it's the incredibly bitter hop resins that attach to the krausen that you are skimming.

I'm not sure this actually suggests that the boil break material also contributes negatively to flavor.

[pyrite]

But I have read in a number of credible sources that the purpose of skimming 'Braun hefe' is to remove the material that contributes harsh flavors such as, hot-break, cold-break and even bitter hop resin that you have stated that wasn't removed before fermentation begins.  I would think that skimming kettle foam is removing protein, the protein that eventually coagulates with the hot-break material.

[tschmidlin]

Either way, something that causes a noticeable flavor in a light American lager might not be noticeable at all in a Rye PA, don't you think?

[denny]

Either way, something that causes a noticeable flavor in a light American lager might not be noticeable at all in a Rye PA, don't you think?

That's a good point, Tom.  As a counter point, although I don't make ALL, I did make a few all pils malt pils this winter.  Not exactly Bud, but still a fairly light, delicate beer.  I did not skim any of them and there was no trace of tannin in any of them.

[tschmidlin]

Either way, something that causes a noticeable flavor in a light American lager might not be noticeable at all in a Rye PA, don't you think?

That's a good point, Tom.  As a counter point, although I don't make ALL, I did make a few all pils malt pils this winter.  Not exactly Bud, but still a fairly light, delicate beer.  I did not skim any of them and there was no trace of tannin in any of them.

Maybe it's because they use 6-row?  I'm just guessing.  I'm with you though, no need to skim, my beers taste great.  If people like doing it, go for it.

[tomsawyer]

Wikipedia (obviously the last word on any subject) says about beer tannins that they are acceptable in some styles (they mention Flanders red, nice touch) but not in lagers.  They also say that tannins and combine with proteisn to form chill haze.

My thought is that the scum is definitely not all tannin, but may contain some complexed with denatured protein.  Whether it contains more tannin than the non-scum coagulate I can't say, obviously there is some small difference in the materials since you don't continue to get scum forming if you skim it initially.  Now how much tannin is in your beer in the first place, is something we have some control over through our crush, attention to pH and sparge methods.  So if theres little tannin to begin with, then it would seem a moot issue as to whether the scum (or braun hefe for that matter) might need to be removed to avoid an off flavor.  We know that some people put the breaks in their beer to no ill effect, including chill haze.  Even if you have haze, you can remove it by fining and thereby remove the tannin component.

I'd think a little tannin might complement more beers than it fouls.  Its certainly a major component of wine, and one that important to the flavor and mouthfeel.

[tubercle]

However, David Miller the author of Continental Pilsener explains that skimming is necessary to remove the harsh, astringent malt tannins before adding the first hops (56-58).

He also claims to get like 127% efficiency in his beers. 

  You can get those figures if you boil long enough

  I prefer the Tubercle method: skim foam or take another sip of beer. Hmmm...Did I mention the laziness factor?

[denny]

Hmmm...Did I mention the laziness factor?

Hey, T, we call that pragmatism, not the "L" word!

[lonnie mac]

I skim a bit. Only because it's there, and I am like, hey, there's something I can do! Otherwise, that gunk is great yeast food.

[tubercle]

Hmmm...Did I mention the laziness factor?

Hey, T, we call that pragmatism, not the "L" word!

  I'll use that to correct the wife ....

[lblikre]

I put it all in the fermenter, even give the hops a squeeze to get that last juice.  By that point my hands have been in sanitizer several times so I don't worry.  I figure it gives the yeast some extra food.  I do have to let the beer sit about a week longer on the backside to settle, but It's always good.