Well, I finally got the courage up to go another round with dry yeast on five hours of effort. The first thing I noticed is that Diamond Lager took longer than W-34/70 to start. I remained calm because Lallemand cultures often take longer than Fermentis cultures to start and the two packages I pitched were from that lot that expires in 10/2021 many people have complained about a certain retailer shipping. What shocked me was the vigor of the yeast once it started to ferment. Granted, I pitched at 55F/13C and bumped up the fermentation up to 58F/14.44C after the wort started to produce gas through the blow-off tube, but we are talking less than 5 days from pitching to succession of fermentation on a 1.068 wort. The fermentation blow-off was so strong and regular that it sounded like someone was kicking the 1-gallon milk container I used to hold blow-off solution. The W-34/70 fermentation took over seven days for a 1.058 wort and was anemic in comparison. I do not believe that Diamond and W-34/70 are the same strain. Diamond produces significantly more H2S during fermentation.
The manufacturers might disagree
Fermentis W-34/70 is genetically most closely related to 2035 American Lager.
To my knowledge, Diamond has not been genetically tested, but it’s doubtful they got it from 2035.
I have posted on this before, but Diamond is the only lager yeast we use now.
I pitch Diamond pretty heavy at 1.7 grams per liter. Pitch at 65 or so as the fermenters filling. Cool it to 50 degrees after full which takes about 30 minutes. from when it’s pitched. By day 5 it’s up to 53 degrees and gets capped to build pressure to 15 psi. It’s nearly at terminal gravity by day 6-7 when the yeast gets harvested. Day 8 start cooling one degree a day. Will keg it about a week later.
I get more sulfur dioxide from it. A little H2S but seemingly less at the higher pitch rate. The sulfur seems to help keep the keg fresh for a long time. Definitely do notice the sulfur diminish as the keg gets emptied and displaced with CO2 from the tank.
It’s a moderate attenuator at 75% or so. I’ve tried to get it to dry out more with mash temps but that’s where it seems to end up for me. I think it makes nice Pilsner and Fest style lagers. The Pilsners could be drier…… maybe……
Love Diamond lager yeast!
Wyeast 2035 and Wyeast 2112 both descend from the Christian Schmidt strain. If W-34/70 groups with 2034 and 2112, then the Christian Schmidt strain more than likely descends from W-34/70 or the parent strain of W-34/70. Fermentis is a French company.
Diamond lager produces a healthy amount of H2S (a.k.a. hydrogen sulfide gas or that rotten egg smell). While it may produce SO2 (a.k.a. sulfur dioxide or the burnt match smell), that is not what I sensed. Diamond lager reminds me more of 2206 than anything else. However, we do not have the plethora of genetics in the lager world that we have in the ale world.
That being said, the beer is smooth with a slight rough edge at this point. That is to be expected with a lager fermentation. Lager fermentations require more time to mature than ale fermentations.
Our experience with Diamond has been nothing short of exceptional. Super clean taste. Yes, maybe a bit of Yellowstone Park sulfur aroma during fermentation, but it does not show up in the taste profile.
The yeast is very healthy, takes off like a nuclear bomb. We pitch straight from the fridge to the wort. No starter required.
I have some W-34/70 in stock. Probably will not use it. And we got two gold medals this year with 34/70.
Thank you Denny!
Sure, but Lallemand deserves the thanks.
I kegged the beer I made with Diamond lager. As I assumed, this yeast is a beast when pitched correctly. Original gravity was 1.068. Final gravity was 1.010.
I repitched 200ml of thick slurry straight out of the refrigerator into 3.5 gallons of 1.064 50F/10C wort and had active blow-off when I checked 14.5 hours later. I have never had a lager yeast perform in this way. Fourteen and a half hours from pitching to strong active fermentation on a 1.064 wort may be par for the course at 68F/20C, but I have never had a lager fermentation start in less than 24 hours at 50F/10C on a repitch when not overpitched. If Diamond Lager and W-34/70 are from the same parent strain, they are very different isolates.
I have pitched a large (1/2 gallon) slurry straight from the fridge into 10 gallons of 50 degree wort. Fermentation was active in less than 4 hours.
The slurry was super fresh, being harvested a week earlier.
The flavor profile between Diamond and W-34/70 is totally different in our experience. We will not use 34/70 again.
We always over pitch. It works for us.
At a pitch rate of 9 times what I pitched on a wort that is roughly 2.9 times larger, I would say that pitching a half gallon of slurry into 10 gallons wort is an overpitch by any measure. That is close to a 1bbl pitch rate. You are clearly not getting much in the way of new cell growth with each successive pitch, but it seems to be working for you. I suspect that you see/will see a decline at about the fifth or sixth repitch, but you have gotten you money’s worth at that point.
With respect to repitching, one of the biggest threats with yeast is petite mutation. However, I do not think that petite mutation is all that common at the amateur level due to the volumes of beer that we produce, especially with dry yeast because dry yeast cultures have to be more robust and stable to survive the process. A lot of current research points to petite mutation occurring in the cone at the end of fermentation due to hydrostatic pressure and temperature. A 3 to 10-gallon fermentation vessel, even a cylindroconical one, does not exert anywhere near the hydrostatic pressure on the sedimented yeast culture that a 300bbl or larger cylindroconical fermentation vessel does.
It would be interesting to see how many times Diamond Lager can be repitched using standard pitching rates before it starts to decline. The cultures we take for granted today were not grown up from slant every few batches. They were basically cropped and repitched indefinitely, that is, as long as they were not infected. It interesting how my sourdough culture has evolved over the last year and a half. I struggled to get it to double during the first month or two. I had to baby it. However, after a year and half, I can ignore it for months at a time, and it does not fail to triple in size when I inoculate 150 grams of whole wheat flour with a heaping tablespoon of the culture. That is the result of adaptation. Selective pressure favored those microflora strains that could survive under my usage. The cultures that we have today are the result of adaptation in a brewery over long periods of time.
Let me qualify my statement…
The total volume we re-pitch is 1/2 gallon. The yeast that is settled in the bottom of the glass jug is probably one quart. The other quart is the beer from the harvest.
This has been standard practice for us, with many different yeasts. The Diamond out performs all others.
When I think slurry, I think thick slurry. I do not count the supernatant that lies above the sedimented solids. I cropped 400ml of roused sedimented yeast and beer from the primary. That sedimented into 200ml of thick slurry and 200ml of supernatant. I discard the supernatant before I pitch the thick slurry.
We normally pitch the entire volume, including the beer on top of the yeast cake.
The yeast settles in a peanut-butter like viscosity, making it difficult to drain from the container. Thus we use the liquid on top as a means of getting it roused up into a workable solution, shaking the bottle until it is easy to pour.
When making a starter with harvested yeast, we decant the entire volume of beer off the yeast.
If you don’t want that beer in your pitch you can discard it and then use a cup or two of the new wort added to the yeast slurry’s container to stir up the packed yeast.
Dang! Call me an idiot for not thinking of that.
Thanks!
There are cultures that stick like glue to the container in which they are cropped, but that was not the case for me with Diamond lager. It is just not that flocculant.
I just kegged a 3-gallon batch that was pitched with 200ml of first generation Diamond Lager slurry. I can honestly say that this batch is the first I have fermented with yeast that started out as a dry culture that is indistinguishable from beer fermented with liquid yeast. The beer is a Vienna-style lager so there are no big, bold flavors to hide off-flavors from the fermentation.
My experience is the same. The Diamond Lager is as good (maybe better) than most of the liquid yeasts we have used.