One of the interesting elements of this for me is the saga of Potosi's Cave Ale. Formerly my favorite beer of all time, all places.
But in summer of 2015 they changed the recipe. Sour finish, lost some of the maltiness I loved....just a real soul-crusher.
The old recipe had an ABV of 6.5 percent. The new one has 5.5 percent. They claimed they didn't change anything with the new recipe, though I know better--they must have reduced the grain bill as their new ABV is down a percent.
They also told me they changed the yeast, but we all know that has nothing whatsoever to do with flavor....right?
I'd guess they saved perhaps 15 percent of their grain bill which, at the scale they're brewing, is likely a significant savings. I just don't like what they did to the beer. Now, this doesn't necessarily explain anything about their brewhouse efficiency, but if they were able to increase that without increasing the grain bill, they'd be closer to the old Cave Ale.
A friend of mine works on the bottling line at the Potosi Brewery. I'm hoping I can get her to introduce me to the brewmaster and find out what yeast they used in the old version. I've also learned that they used US Goldings as the hops; if I can get the right yeast, I might be able to clone it. I've been trying, and while it's close, it's not quite there.
if they changed the recipe to hit a lower ABV and changed the yeast they are no longer brewing Cave Ale and should have changed the name too. :rockin: