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Bill the Brewer Talks PCR's and Deep, Deep Connections

In another guest post from Bill the Brewer he talks science, the need for deeper connections and walking through the pearly gates... Enjoy: 


In our fast paced brewery, the “very cool” occurs everyday. But most of it goes unnoticed, as different departments become more like petri dishes, operating autonomously.  At its worst, the right hand does not know what the left hand is doing, and it is a miracle we get any beer out the door at all. At its best, the brewery sings with remarkable harmony.

One really neat thing that takes place a few times a week is in the Micro-Lab. It sits, unassumingly, on the work counter -and looks like a sleek R2D2- or a high-end espresso machine- it is called a Thermal Cycler or Real Time Polymerase Chain Reaction machine. It is a piece of laboratory equipment that is used to detect the presence of beer spoiling micro-organisms. Until recently, this machine was too expensive for all but the biggest of breweries to own. Now, thanks in part to open source software, the price has come down significantly and is not uncommon in larger craft breweries.

Now, most brewers  keep their  equipment clean and sterile, follow  all good guidelines for sanitation, and yet, sometimes, a few evil cells make their way into the beer, growing slowly and stealthily, and when you take that coveted six-pack home you find horrible off-flavors that bring you down faster than a power outage during Breaking Bad. We cannot- we will not- let this happen. Enter the PCR machine!

A beer sample is placed in a magic solution before it goes into the PCR machine. Within this solution, there are 23 DNA “primers” that match the DNA of beer spoilers. In the machine, the solution goes through several cycles of heating and cooling. The purpose of this is to rip apart the DNA of all living organisms in the solution. This is called melting. These broken up strands of DNA are quite unhappy. Like every other substance in nature they long to bond with something- anything- in order to be whole again. So they bond with the florescent primers, causing an enzymatic reaction which makes them fluoresce brighter.  It is called a “real time polymerase chain reaction” machine because it records and charts the time and temperature when the indicators fluoresce! After this runs through a few cycles of melting and re-bonding, a chart is created. This chart is compared with other charts of known beer spoiling bacteria, and this is how we know whether or not we have a huge problem. If the beer is already in the marketplace it will be recalled. If it hasn’t left the brewery then it will be dumped down the drain.

Sacrilege, you say? There is an Old Catholic saying that goes “you cannot get into heaven until you have drunk every drop of beer that you have wasted on Earth.” At this point, I have accepted the fact that I have so much beer to drink before I can pass through the Pearly Gates that there is no doubt I will not remember having done so.

It is entirely possible that I am already there.


Heady, thanks Bill.


Talk soon, 

-Juicebox