In recent years there has been a lot of interesting information published from the DNA sequencing of yeast strains. One of the most interesting bits to me has been WLP540, purportedly from Rochefort, being closely related to English strains rather than Belgian. Also notable is that the strain is POF(-), meaning that it does not produce phenolic compounds like other Belgian/Trappist strains. According to BLAM, Rochefort’s current strains were sourced from the Palm brewery in the 1950’s, after not having much success with Chimay’s yeast in their beers. What’s interesting is that I definitely pick up some phenolics in Palm, so I don’t think that this can be the same strain.
Based on this, I decided to play around with the Rochefort strain. I will note here that I am using Wyeast 1762 rather than the White Labs strain. This is primarily because it has year-round availability. It is widely believed that this strain is an equivalent to WLP540, and it certainly tastes reminiscent of Rochefort to me, but until we see a genome I will make no absolute claims.
I have used 1762 in the past for an English Barleywine, and it did great in that style. That said, it was many moons ago and I don’t have very detailed tasting notes. I don’t recall any specific yeast character in it, though. A few months back, I decided to try out a very simple Bitter recipe using this strain (Pale malt and Invert #2, with Syrian Celeia throughout). My initial impressions were that the fermentation was quite clean, but the beer was still pretty young and needed time to age a bit. A month or so later I came back to the beer, and I keep going back to it over and over. I am really surprised by how clean the fermentation character is. I keep thinking I’m getting flashes of red fruit, but they’re fleeting and I’m honestly not sure if that is just confirmation bias on my side. There is none of the hallmark dark fruit/raisin/fig that is prominent in Rochefort’s beer. I’m not sure if there is any biotransformation going on, but it certainly lets the hops come through well.
This beer is so good, that I pulled a few ounces to start stepping up a starter for my next brew. My other planned experiments will have to wait. I will definitely be using 1762 in several different styles, next up is a brown porter, but there will definitely be an IPA in the future as well. I could see this being a "house strain" in a brewery that is capable of producing a broad range of styles.