Hmm...now I'm more confused. If you put "myth" in quotes because you don't think it's a myth, why are you saying that the myth-in-quotes isn't true?
How about the 'myth' is an oversimplification of what is in actuality a very complex process involving numerous factors, of which the claimed primary driver (cell division) is at best a bit player?
Keep in mind the myth is "esters are produced during cell division". That is, plainly put, wrong; esters (the ones which create flavours) tend to be produced post-replication, when the cell is no longer using the various ester-creating biochemical pathways and acetyl-CoA for lipid synthesis. Yes, during lipid synthesis other esters are produced. But these are in the form of insoluble lipids which (yeast bite aside) generally don't impart much to the flavour of the beer.
In any case, I'm not sure I follow why gene knock-out experiments or other available acetyl-CoA sinks should undermine the notion that ester formation is related to kinds of lipid synthesis tied to reproduction. There's a world of difference between 'essential' and 'advantageous' as far as evolution is concerned. Simply put, ester production requires metabolic energy, so it's very hard to justify the idea that it does not serve a purpose.
I never said it didn't serve a purpose; rather I said that the idea that during fermentation ethanol-esters are used to provide a 'sink' (buffer, whatever) for acetyl-CoA:CoA levels is likely incorrect. Evolutionarily & biochemically that makes no sense. In contrast, what I said (and you've now repeated), fits biological expectations - i.e. the role of the ester-producing enzyme systems is one of lipid formation, and the nice (or unwanted, depending on style) side-effect of soluble (flavour) ester production is merely the outcome of placing yeast in an unnatural environment where these pathways then act in a fashion that has nothing to do with their evolutionarily-derived purpose.
But to come back to the main point, cell division is not when the flavour esters are generally produced - during cell division those enzymes are a) limited due to competition with other cellular processes for acetyl-CoA, b) expressed at low levels due to the presence of oxygen (they get upregulated in anaerobic conditions) and c) are being used to produce medium-chain lipids, not flavour compounds. Its only after the lipid-synthesis phase is complete (i.e. post-oxidative growth and/or cell divisions) that you generally see the formation of soluble esters that provide flavour to beer, due to the combined effect of more ester transferase expression, precursor availability, and acetyl-CoA availability.
This gets above my pay grade quickly, but for exactly that reason I'm inclined to believe Briggs and Bamforth when they tell me that a yeast growth cycle is necessary for a "normal" ester profile.
But now you're talking about a completely different thing. To get ester production (either to make lipids or to make flavour compounds) you need the yeast to make the precursors, which is an aerobic process. Cell division is not required - but its also hard to put yeast into an aerobic state, along with everything else they need to make precursors, without having them divide. Your bead system may be an exception to that - there is no (biochemical) reason why you shouldn't get proper ester production, and you should be able to generate precursors (without cell divisions) by exposing the yeast to aerobic conditions - i.e. by oxygenating your wort.
Its a pretty cool experiment - and may be a way to exert a level of control over the yeast that we don't normally have. Removing cell division from the equation may allow much finer control over esters/phenolic production, attenuation (as others already mentioned), etc, as most of the interventions we can make (temp, oxygenation, etc) would impact strictly on biochemical processes and not on yeast growth.
Bryan
