Yuck! That Yeast Is Flocculating Itself Again!!!

When I was a home brewer – as opposed to a person who has home brewing supplies and equipment in the house but never does anything with it all – I used to be concerned about flocculation. Flocculation is the word that describes the capacity of a yeast (or other stuff for all I know) to clump. It is a fancy pants word for clumpiness – but is more about the propensity to clump as opposed to the clump itself. I think. If a yeast strain floucculated too much it could cause precipitation leading to poor attenuation due to separation of yeast and wort. Yet if the yeast was under flocculating there would be difficulty in settling out and creating a bright beer. I think.

So, it is comforting to know that all my half baked understanding of yeast clump-a-bility is actually related to a massively important scientific moment:

A team of scientists at Harvard University reported last week that they isolated the single gene that allows yeast to stick together. That gene allows the normally solitary yeast cells to shield themselves from toxins in their environment by banding together in protective balls. Since one of those toxins is the ethanol that the yeast themselves produce, grouping together allows the yeast to survive in the alcohol-rich environment that results from brewing. What’s more, the gene has a built in social value system that prevents yeast cells without the gene from taking advantage of the yeast flock’s protective sphere. That social control mechanism is an example of how single cells can regulate function in larger units.

Excellent! I knew that something about beer was out there promoting social values…or is it promoting socialism!?!?¹

The point? As Kevin Verstrepen, one of the eggheads in white lab coats² – a Haavaad man no less – notes: “You can look at it as a model of how single-cellular organisms can cooperate, taking a small step toward multicellular life.” A-ha! No, not the Norwegian 80’s band…I mean “a-ha” as in light-klicky-on, as in “EUREKA!!!” So not only was the creation of civilization dependent on beer but the core zymurgystic fact of beer is also the same core fact of complex life as we know it. See? Without the making of alcohol, we are all single cell amoeba… amoebae… amoebas. I think. Which leads me to my amoeba joke: “two amoeba leave a bar and look up at a bright light. One says to the other ‘is that the sun or the moon?’ to which the other replies ‘I dunno. I don’t live around here.'” Get it? That is what we would have to put up with were it not for the flocculating powers of yeast. And nobody wants that.

^¹Cue the theremin music!
^²…and let’s not have a repeat of the whole “sensitive yeast scientist” thing this time, ok?