Tom, Many years ago when fermenting "open topped" a white scum would often form & it was then considered desirable to skim off. Frankly my experience in those days was of frequent failure & often the amount of scum seemed to indicate the likelihhod of a sound brew IE with less scum. These days in closed topped fermenters, it is difficult even to see if there is any scum. But I think generally there isn't any. So now no big deal, just be wary if you see a scum which developes uncharacteristically.
Pete
Is it critical to skim the scum off your primary fermentation? Some books
> suggest this stuff contains fusil oils and other undesireable compounds > that
> may affect the final flavour. My experience says it is not a big deal. > Comments?
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> Uncle Tommy
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