Today was a great example of brewing theory. Over the last week, we have talked about how to improve shelf life. One professor told us how filtering damages beer stability, another told us that filtering could slightly improve beer stability, and another one said that sterile filtering is an absolute must for bottled beers. Clearly, there is no right answer. You can look around at great craft breweries throughout the USA and see the different schools of thoughts. Bells, for example, does not filter or even use fining agents in their ales. They do filter their lagers. Some breweries, like Sam Adams, use a very fine filter and filter out even the smallest particles out of their beers. Some use coarse filters and get out the larger yeast cells, while leaving behind the small cells. And then there are even a few that filter out everything, and then add yeast back in right before bottling.
So now within my group of classmates staying in one apartment, we have six brewers with six different opinions on filtering.
At the end of the day we had another palate training session. We used Budweiser as our control beer and tasted 10 different flavor compounds. We had diacetyl (butter taste), Iso-amyl-acetate (banana ester), acetaldehyde (green apple), Eugenol (spicy phenol), fusel (rancid alcohol), boozy (Budweiser spiked to 10% ABV), and a few others.