I was reading Zymurgy this weekend. I noticed a response about some confusion over best pitch rates to increase (or decrease) isoamyl acetate ester production, which gives German/Belgian beers its characteristic banana character. The comment was that high pitch rates contribute to this flavor - since the yeast do not need to use the precursor (Acetyl COA) to grow, more esters are produced. This confusing point jived a bit from what I've researched concerning American breweries brewing Belgian styels; that is, some seem to pitch high, some seem to pitch low, at varying temps (some cold, some warm.) The larger question for me (right now anyway) is if this is true for esters in general. ie, if I wanted to produce a very clean ale, should I pitch a bit higher than normal or lower? Wyeasts site says: A low pitch rate can lead to: Excess levels of diacetyl Increase in higher/fusel alcohol formation Increase in ester formation Increase in volatile sulfur compounds High terminal gravities Stuck fermentations Increased risk of infection High pitch rates can lead to: Very low ester production Very fast fermentations Thin or lacking body/mouthfeel Autolysis (Yeasty flavors due to lysing of cells) This sounds somewhat in contrast to what I am describing above. Any anecdotal or (even better) scientific theory as to why one is better than the other would be appreciated.