Rehydrating us-05 - temperature and time

[Hopper5000]

If they were rehydrated at 85 degrees in 115 ml of water (I'm assuming) my guess is that it should have cooled down to room temperature within the 30 mins?

Did you check the temp before pitching?

No I didn't check the temp, just assumed. There was a bit longer of a lag phase than usual but it's going strong now.

 

[OrdinaryAvgGuy]

No I didn't check the temp, just assumed. There was a bit longer of a lag phase than usual but it's going strong now.

Yeah, if you rehydrated your yeast at 85 degrees then let it sit at room temp for 30 mins then you were likely in the low 70's by the time you pitched it.

 

[Hopper5000]

ya i wasn't really that worried, it was just a thought... i was more thinking about it being a factor when hydrating at 100F or so

 

[boydster]

So I figured I should follow up on this thread. I just got an email back from Fermentis. Below is what I sent them, and the response I received.

Me:

Hello, I asked this question several weeks ago and have not heard back. I have seen multiple sources that say dry yeast should be hydrated at temperatures that are warmer than Fermentis suggests for US-05 and S-04 (sources say all dry yeast have an optimal temp range of 95-105F for hydration, while Fermentis recommends temps closer to 80F). I am trying to understand why the discrepancy. Is there something different about Fermentis yeasts? Or is the recommendation based on ease of use? Would I do any harm, or would I potentially do my yeast a favor, if I were to rehydrate it at 100F?

Please let me know. If it really is the case that Fermentis yeast is different, I think that is really neat and I would love to know what exactly it is that differentiates your yeast from others with respect to optimum hydration temperature.

Regards,

Fermentis:

I am sorry to come back late with the answer.

First of all, we would never recommend any procedure that could potentially harm the yeast and alter your beers. Second, I don’t know what the competitors are doing, but I can confirm that our hydration instructions are validated by our R+D Center, located in Lille, North or France and several Institutes and Universities that have been collaborating with us during the last 15 years. Our yeasts and use recommendations protocols were also validated by the market for 15 years; prove of that are the thousands of homebrewers, microbreweries, regional and industrial breweries that currently chose our yeasts, making Fermentis the leader in this segment all around the world. In addition, we belong to the Lesaffre Group, which is world largest active dry yeast manufacturer. In fact, the group is producing active dry yeast for other industries since the beginning of the 70’. We are pioneers in this field in terms of quality and innovation.

Despite my words above, it is not my intention to answer your question, just trying to impress you. The explanation is that we recommend this hydration temperature based on exhaustive tests at temperatures more comfortable with the brewing process. It is safe, secure and do not harm your yeast. The reason why we can do it and not our competitors is not completely clear for me, but it is for sure related to the production process (mainly the drying of the yeast) and not to the strains themselves. Our yeasts can tolerate lower hydration temperatures due the Lesaffre technology.

Hope my words can answer your questions.

I wish very nice brews.

Best wishes,

 

[stpug]

So I figured I should follow up on this thread. I just got an email back from Fermentis. Below is what I sent them, and the response I received.

Me:


Fermentis:

Clear as mud

 

[OrdinaryAvgGuy]

So I figured I should follow up on this thread. I just got an email back from Fermentis. Below is what I sent them, and the response I received.

Me:


Fermentis:

Sounds like a whole lot of fluff. So their dehydration process enables them to offer a product that hydrates at a much lower temperature. Okay - fair enough.

I tried US-05 for the first time on Friday. I boiled just over 100 ml of water and allowed to cool in a sanitized mason jar. It took roughly 90 mins to cool to 76° at room temperature with a piece of aluminum foil placed lightly covering the top. It mixed fairly well, although I could see how the water being warmer could make it easier to mix.

Using this process I had signs of fermentation around 18 hours @ 65°.

 

[boydster]

I'm not saying I'm satisfied, just posting it here for all to be on the same page. From what I can decipher, they have magic on their side. And pure, unadulterated awesome. Who needs to present data when you have that 1-2 combo going for you?

 

[Puddlethumper]

I'm sorry if I'm a cold plug in this discussion but I happen to appreciate the fact that Fermentis responded to the email in the first place.

I happen to be employed in an industry that is rife with second-guessing by outsiders who think they know a lot more than they actually do. The PhD's in their lab coats aren't PR guys trying to sell the public a bill of goods. Most of the time those guys are putting those advanced degrees to work doing really good science that the general public simply doesn't (often can't) comprehend.

The people at Fermentis are probably not all that concerned with providing extensive data to some random home brewer to support what hundreds of thousands of dollar's worth of research has taught them. Especially when some of that information is quite likely proprietary, bought and paid for with those same R&D dollars.

I, for one, am not inclined to second-guess those lab-coats. I've learned to read and follow the manufacturer's label instructions for the products I handle every day. And you know what? When I do that I find I can count on those products' performing exactly as advertised.

 

[boydster]

I don't disagree with you, Puddlethumper, and I also appreciate the fact that they responded finally. The person who wrote back to me isn't in the R&D department though and admitted as much. I actually wrote back asking "let's say I rehydrate 2 brand new packs of US-05; one at 80F and the other at 100F. Which packet would have higher viability?"

From Fermentis:

You can reach our specs on our website (http://www.fermentis.com/wp-content/uploads/2012/02/SFA_S04.pdf). We inform our active dry yeasts contain >6exp9 viable cels/g, following the proposed rehydration protocol. This number is the one you need to consider.

As I told you in your previous e-mail, I don’t know why competitors inform 100 °F is the ideal rehydration temperature. I have two possible explanations: 1) They have never improved the drying process and dried cells are weak to support rehydration at low temperatures (elasticity of the membranes is affected at lower temperatures, thus increasing cellular breakdown) or 2) They have never validated the rehydration al lower temperatures, despite any potential improvement in their technology.

I don’t have any chart showing viability vs rehydration temperatures (I am not part of the R+D). However, the most important for our customers is that we are consistent with the informed specifications. So, any chart is irrelevant in this case. If we inform lower temperatures it is because this is the best rehydration temperature for the yeast concerned.

If you are not yet satisfied with my answer, I invite you to design an experimental protocol and test your hypothesis. Please, be sure you will be using the correct lab techniques.

I guess my only frustration is that I'm asking what should be a simple question and I just wanted a straightforward answer. At least they answered though, and I did send one last request to the rep to see if he would mind forwarding my question to R&D to see if they had a quick and simple answer. It really only makes a difference on big beers - in gravity and/or volume - but I make high OG beers sometimes so I'd like to know. And honestly, that 6x10^9 figure is not exactly a selling point - if each packet really had only 69 billion cells in it after being rehydrated, I wouldn't be using it. Plus, other reps from Fermentis have stated the packets leave the production line with an average of 150 billion cells per 11.5g packet, and independent cell counts from other people have arrived at similar cell counts.

 

[Puddlethumper]

I guess my only frustration is that I'm asking what should be a simple question and I just wanted a straightforward answer.

Sorry if I came off a little harsh. (Spent some time on the phone yesterday with just one of those people I was describing!)

And I do hear you. I've run into similar roadblocks to information in my industry. Fortunately, because we purchase significant quantities of the materials we handle, the manufacturer's reps tend to take my inquiries a little more seriously. As a result I usually end up getting the information I was seeking.

However, it is important that we all realize that if I was a homeowner who picked up an occasional bottle of their consumer-level products I doubt they would provide me with much more information than what they have already published.

Cheers!

 

[sablesurfer]

I guess my only frustration is that I'm asking what should be a simple question and I just wanted a straightforward answer. At least they answered though, and I did send one last request to the rep to see if he would mind forwarding my question to R&D to see if they had a quick and simple answer.

Why the heart ache? If you don't like the product then just use a different dry yeast. Seriously. And you didn't ask a simple question. You asked a question that BOOKS have been written about. I just read one a while ago. There are entire companies built around how a yeast is harvested, cultured, preserved, and served to the customer. This is not a simple question. If it was so simple...then you'd be able to do the very experiment they suggested.

Hell, I am not sure why you haven't experimented already to find what works for you, in your situation, on your beers. There seriously isn't any "the answer" in brewing. Not at all. Ask any pro-brewers if they are doing the exact same thing from job to job or from homebrewer to pro...every anecdote I have read in any book says they are not. Everything is adapted to how beer works in your environment. EVERYTHING else, is just suggestions.

I rehydrated my US-05 on my last IPA, just to see what the hoopla was about, and I will say it has been my worst effort on IPA to date. The lingering fermentation flavors will just not go away, almost three weeks after kegging.

 

[stpug]

I rehydrated my US-05 on my last IPA, just to see what the hoopla was about, and I will say it has been my worst effort on IPA to date. The lingering fermentation flavors will just not go away, almost three weeks after kegging.

Ahhhhh, but WHAT temperature did you use? (just kidding - couldn't resist)

 

[BeerGrylls]

I actually wrote back asking "let's say I rehydrate 2 brand new packs of US-05; one at 80F and the other at 100F. Which packet would have higher viability?"
...
I guess my only frustration is that I'm asking what should be a simple question and I just wanted a straightforward answer.

Please don't take this the wrong way, I'm not trying to be inflammatory. It looks to me like the answer was straightforward (although breathy) - that the stated directions on the package are the best ones, for this brand of yeast. I'm wondering what answer you're really looking for to be satisfied? I doubt very much they will provide you with their lab analysis data.

 

[boydster]

Why the heart ache? If you don't like the product then just use a different dry yeast. Seriously. And you didn't ask a simple question. You asked a question that BOOKS have been written about. I just read one a while ago. There are entire companies built around how a yeast is harvested, cultured, preserved, and served to the customer. This is not a simple question. If it was so simple...then you'd be able to do the very experiment they suggested.

Hell, I am not sure why you haven't experimented already to find what works for you, in your situation, on your beers. There seriously isn't any "the answer" in brewing. Not at all. Ask any pro-brewers if they are doing the exact same thing from job to job or from homebrewer to pro...every anecdote I have read in any book says they are not. Everything is adapted to how beer works in your environment. EVERYTHING else, is just suggestions.

I rehydrated my US-05 on my last IPA, just to see what the hoopla was about, and I will say it has been my worst effort on IPA to date. The lingering fermentation flavors will just not go away, almost three weeks after kegging.

I love US05. I have experimented on my own beers and if I had a scope and hemocytometer, I'd do the cell counts myself. But I don't, and far be it for me to think that the manufacturer would know if there was a difference in cell viability at 80F vs. 100F.... that doesn't seem like a tough answer and I asked that question point blank. Further, it's come up in discussion on HBT once or twice, so instead of perpetuating anecdotes and speculative answers, I figured I would go to the source. The more difficult answer would be explaining the biology behind why their yeast's ideal rehydration temp is 80F, but on my follow up email I dropped that question entirely.

So rehydrating 05 ruined your IPA, huh?

 

[boydster]

Please don't take this the wrong way, I'm not trying to be inflammatory. It looks to me like the answer was straightforward (although breathy) - that the stated directions on the package are the best ones, for this brand of yeast. I'm wondering what answer you're really looking for to be satisfied? I doubt very much they will provide you with their lab analysis data.

They gave an answer, and it was good that they took the time to respond, I am happy about that. It's where he says "The explanation is that we recommend this hydration temperature based on exhaustive tests at temperatures more comfortable with the brewing process" that made me wonder more specifically about what harm or benefit would come from hydrating at higher temps and I feel like he went out of his way not to answer that. If you get 80% viability at 80F (for instance, I'm not saying that is a fact), then that's pretty darn good and certainly higher than the 6x10^9 cells per gram guarantee he mentioned in the email. However, I still don't know from what they told me if I would potentially get a higher viability if I used a higher temperature even if that temperature is higher than what they consider "comfortable with the brewing process," and that was the question I really wanted an answer to. It's fine, either way I know 05 is a great product and from other people's results we can see we get a lot of very healthy cells by hydrating in 80F water and once i get set up with some yeast lab equipment I can test some things myself.

 

[sablesurfer]

Ahhhhh, but WHAT temperature did you use? (just kidding - couldn't resist)

I used countertop temperature.

Basically I boiled water at some point when boiling kettle. Water in measuring cup with aluminum foil top. It kinda sat there until I got around to putting wort in fermentor. I pitched it then in boiled water...prolly in the low 80s as I test by measuring cup is slightly warm. I shake areate my wort for ten minutes on a timer. Then pitched rehydrated into fermentor, so it probably sat in water close to 15-20 min total.

So super scientificy.

 

[Puddlethumper]

I love US05.
So rehydrating 05 ruined your IPA, huh?

LOL, all this discussion has gotten me curious. I've been using BRY-97 for all my American ales lately so will have to go back to US-05 for a batch or two to see how it does for me now. The last times I used it I got a very vigorous fermentation and a decent brew followed. I only switched to the Danstar yeast because it yielded a little drier beer.

What I have learned since then is that I get my best results when I rehydrate per the package instructions, cool the wort to a few degrees below fermentation temperature, then gradually temper the hydrated yeast down to within 10F of the wort temperature. Pitch the cooled yeast and let everything warm to fermentation temperature from there.

 

[sablesurfer]

So rehydrating 05 ruined your IPA, huh?

I have problems with 05 that no one else in the world seems to have. No idea why. Other yeasts come out clean in my house, 05 always leaves some weird garbage/vegital aroma taste. (However, I know I am not the only one, because I have found two micro/nanos where their beer makes me thing..."Oh, I brew this at home"...LOL)

So yeah, I attempted a rehydration step. This time appears worse.

Already planning next steps to find a solid IPA yeast for my place. 5gal brew, simple recipe, split between three 1gal fermentors. Will pitch 'half' a dry yeast packet from...05, bry-97, and if I can't get Mangrove Jack's West Coast then I will try Nottingham/Windsor for some British comparison. I figure half a package into ~1gal wort will be a big pitch.

Have to get this worked out. I love big fruity DIPA's, but just can't get anything I am happy with for a base IPA recipe yet.

 

[boydster]

Bummer. I wonder why it does that for you? I really like Notty for IPA's if you can control the temp to the lower end (I start at about 60, I've heard from others that start a little lower than that even with good results, like 58F). Haven't used BRY-97, mostly out of sheer laziness because it's available at my LHBS so I really have no excuse I never seem to like the attenuation of Windsor for hop-forward beers, it seems like it leaves more malt character and a higher FG than I want in those beers. That's just my .02 though, and the current exchange rate puts the value at about 1/10 of that

 

[sablesurfer]

Notty vs windsor - good feedback. I have liked them both in other beers. Don't want to be losing any more hop character.

 

[thefost]

I'm not sure if you've seen this, but there were some experiments with yeast viability conducted here:

http://seanterrill.com/2011/04/01/dry-yeast-viability/

Strangely, he found that rehydrating at 64F yielded higher viability than 91F. Since both tests yielded viability within 4%, this mainly proved to me that simply rehydrating in water rather than wort is much more important than the rehydration temperature. I would love more experimental evidence on this though.

 

[Puddlethumper]

Already planning next steps to find a solid IPA yeast for my place.

You might like the way -97 turns out. Be aware though that it doesn't have a big rolling fermentation like -05 or Notty. I ferment at 66F and get a slow, soft bubbling in the airlock after 36-48 hrs that continues for quite a while. It attenuates like it should and drops out cleanly. After 8 days +/- it has reached FG and is ready to cold crash for a couple days then package. I have left the beer on the yeast for as much as a couple weeks with no change in gravity and no noticeable change to the flavor of the beer.

And +1 on the suggestion for Nottingham if you can keep it cool enough.

 

[Beenym88]

I know this thread is super old but I’ve never rehydrated 05 and if my wort is above 1.05 I pitch two packs. I’ve always had bubbling within 12 hours. I know it’s supposed to be better to rehydrate but when using one that is specifically made so you don’t have to online to just skip it.