Cross posting a recent Reddit post I made in /r/homebrewing.
So what is Philly Sour?
Philly Sour is a Novel Lachancea spp. yeast that is capable of producing lactic acid while also producing ethanol. It basically does all of the cool fun things that we want a yeast to do while still (and including) helping us make beer.
As for it's discovery, it was isolated by the Brewing Science team over at the University of the Sciences in Philadelphia headed up by Matthew Farber, PhD.
There's a ton of information that Dr. Farber has put together in a livestream video which I highly recommend watching. You can find it here.
So what can I do with Philly Sour?
Make sour beer! Philly sour is, to the best of my knowledge, completely hop/IBU tolerant which means you can use it to replace most yeast for most styles. What you'll end up getting is something resembling an ale with slight stonefruit/peach/red apple esters and a bunch of tartness.
According to Dr. Farber, Philly Sour is also pretty easily out competed which doesn't make it a good candidate for co-pitching. You can, however, finish a beer off with another strain. According to his studies this yeast has shown to sort of produce most of it's lactic acid up front, mostly within the first 4-5 days. Right now there's just not a ton of information out there on what that would look like so it's probably going to be on us as brewers to start using our imaginations as to all the possibilities.
So what did I make? A sour NEIPA of course!
So traditionally I don't think that tart and bitter go together all that well. I still don't, but I still wanted to try this style. The goal was to add very little bitterness while still pumping it full of hops. To that end, as I didn't add any boil hops, I probably could have just done a no boil but I like to enjoy my brew days and find that boiling gives me time to do some cleaning and play with other stuff around the brewery.
For hops, I used what I had in smaller vacuum sealed packs that I wanted to get rid of since this was sort of an experiment anyway. I ended up with a little Bru-1, little Sabro, Citra, and Galaxy.
Shout out to /u/defubar for the grain bill below. He's the first person I know who used this yeast and basically gave me a starting point for a recipe. The purpose of the dextrose in the recipe below is that, according to Dr. Farber, around a 2% addition of glucose to the drives the esters to be more stonefruit and peach like instead of red apple. It also drives down the pH and, supposedly, the TA. I don't have the tools to measure TA so sadly I don't have a number for this.
The recipe is as follows:
Type: All Grain
Batch efficiency: 72.0 %
Boil size: 7.5 gal
Boil length: 60 min
Batch size: 6.5 gal
Estimated OG: 1.061
Actual OG: 1.061
Estimated FG: 1.011
Actual FG: 1.008
Estimated SRM: 4.9
Estimated ABV: 6.6 %
Actual ABV: 7.0%
Final pH: 3.3
Pretty standard 150ppm Chloride to 100ppm Sulfate
|Pilsner (Weyermann)||Grain||1.7 L||10.00 lb||66.9|
|RoastOat||Grain||7.3 L||2.00 lb||13.9|
|White Wheat Malt||Grain||2.4 L||2.00 lb||13.9|
|Corn Sugar (Dextrose)||Sugar||0.0 L||0.37 lb||2.6|
|BRU-1||U.S.||15.0 %||1.0 oz||20 min||Whirlpool (160 F)|
|Citra||U.S.||12.0 %||1.0 oz||20 min||Whirlpool (160 F)|
|Sabro||U.S.||16.0 %||1.0 oz||20 min||Whirlpool (160 F)|
|BRU-1||U.S.||15.0 %||1.0 oz||20 min||Whirlpool (110 F)|
|Galaxy||Australia||14.0 %||1.0 oz||20 min||Whirlpool (110 F)|
|Sabro||U.S.||16.0 %||1.0 oz||20 min||Whirlpool (110 F)|
|Citra||U.S.||12.0 %||1.5 oz||9.0 days||Dry Hop (High Krausen)|
|Galaxy||Australia||14.0 %||1.5 oz||9.0 days||Dry Hop (High Krausen)|
|Citra||U.S.||12.0 %||1.5 oz||2.0 days||Dry Hop|
|Galaxy||Australia||14.0 %||1.5 oz||2.0 days||Dry Hop|
|Philly Sour||Lallemand||Ale||82.5 %|
Fermented at 72F for the batch’s entirety.
|Mash In||Infusion||156.0 F||60 min||4.8 gal|
|Batch Sparge||168.0 F||15 min||4.8 gal|
So how did it turn out?
It's still a touch green but it's really fun! Between the hops and the yeast it's got this pineapple, grapefruit, lime flavor going on that's pretty enjoyable. As it warms I think the lime fades a little and you sort of get more tropical flavors out of it. It's very much tart and I would love to add some fruit next time. I think some sweetness would really round a beer like this out.
The bitterness is almost non-existent which I'm thankful for. In my normal NEIPA's I dig just a bit of bitterness to really round out the beer but I wasn't super excited to have anything like that in this recipe. I think I pretty much succeeded there.
As you can tell from the picture above the head is pretty much non-existent. Due to (I'm assuming) the pH / TA it fades pretty quickly after it's poured but the color turned out gorgeous. I may actually go for a little honey malt or something next time to just to bring a little more orange into the picture.
It really was a breeze brewing with this stuff though and I'm pretty convinced already that I'm likely not going to be doing kettle sours again. Time will tell though!