Dry yeast less tolerant of temperature swings/heating?

[Adr_0]

Of the last perhaps 6-7 beers I've made, two have had reasonable chunks of acetaldehyde and looking back, both needed a lamp in the freezer and potentially had some temperature swings (bouncing between the lamp and freezer). One was the MJ's saison and this latest has been M44.

The saison was tasting awesome until I put the lamp in, and the M44 had a temperature dive then had a bit of up and down - basically between 15 and 18°C at times. Lots of acetaldehyde.

By comparison, liquid yeasts have at times had some temperature bounce and/or heating from the lamp and have been clean as a whistle.

I have rehydrated properly for both dried yeasts. Could I be overestimating the viable yeast and the temperature/heat is causing too much stress?

 

[ein stein]

why is your temp swinging so wildly?
im using an incandescent bulb as my heat source but i painted it with black stove paint and let it cure by leaving it on for a day (lots of fumes came off it) and i only get temp variations of 0.3c which is the minimum i can set my stc to. ive only been using dry yeast but have never had major issues with acetaldehyde.

 

[Dae Tripper]

Stright from the BJCP website (lol BJ)
Characteristic Possible Solutions
Acetaldehydefresh cut green apples Make sure fermentation is vigorous using healthy yeast. Allow full attenuation. Leave beer on yeast longer. Oxygenate wort fully. Try another yeast strain. Make sure sufficient yeast nutrients are available. Let beer age longer.p

 

[MHB]

Why are you trying to ferment at 15-18oC, Most ale yeast will be impeded below 16oC, having the temperature wander back and forward under 16oC could be quite a big stressor.
Better to ferment at >18oC and get a quick clean ferment.
The info on M44 recommends fermenting at 18-23oC, recommends sprinkling onto the wort rather than re-hydrating. So that's two things you are doing that the manufacturer doesn't recommend - try doing it their way and see if that improves the performance.
Mark

 

[klangers]

Why are you trying to ferment at 15-18oC, Most ale yeast will be impeded below 16oC, having the temperature wander back and forward under 16oC could be quite a big stressor.

I had exactly the same issue as AHB, but simply because I underestimated the self-heating effects of a cider fermentation, didn't put a heater on the controller, and it went too cold and then swung around a bit. Very sulphurous on the nose, and horrendous solventy acetalhyde.

Whereas the cider that went hotter and quicker is clean as a whistle.

 

[Adr_0]

I've used MJ's Empire Ale in a beer and it's come out great - this was a 9-10L batch and there was a bit of temperature variability but it was over summer so no heating in the freezer.

I had exactly the same issue as AHB, but simply because I underestimated the self-heating effects of a cider fermentation, didn't put a heater on the controller, and it went too cold and then swung around a bit. Very sulphurous on the nose, and horrendous solventy acetalhyde.

Whereas the cider that went hotter and quicker is clean as a whistle.

Yes, this is exactly what happened.

Why are you trying to ferment at 15-18oC, Most ale yeast will be impeded below 16oC, having the temperature wander back and forward under 16oC could be quite a big stressor.
Better to ferment at >18oC and get a quick clean ferment.
The info on M44 recommends fermenting at 18-23oC, recommends sprinkling onto the wort rather than re-hydrating. So that's two things you are doing that the manufacturer doesn't recommend - try doing it their way and see if that improves the performance.
Mark

I had set my freezer to 16.5°C expecting that M44 would be like US-05 (15-22°C) or BRY-97 (15-22°C) and so that would be an appropriate setpoint to start. Without heating it dropped to 14.8 or 15°C and then I let it warm up to 17, 18 then 19°C and it progressed steadily from there. Keep in mind my point/query is around flexibility and accommodation of some temperature fluctuations vs liquid strains.

I put a freshly brewed hefeweizen in the freezer (still 25°C or so from post chilling) and had the freezer set to 17°C, but unfortunately an IPA that was in there too got down to 12-13°C, and a couple of days later is now in the mid 18's. This was using 1275. It hiccuped in the attenuation but still tastes very clean.

The M44 ferment took 30hrs to form any sort of krausen, while the 1275 IPA had a good krausen after 6-7hrs and had a great starter, etc. I would probably put the acetaldehyde down to temperature swings/heating but the 1275 batch rode through it a lot better - which makes me think it's possibly cell count/vitality.

An MJ saison had a similar experience and was tasting excellent until having some temperature swings in the mid-high 20's where the acetaldehyde just rocketed up. Sure, that sounds pretty rough but I've had the Dupont strain do a similar thing while sitting outside and produce a stunning, clean beer - clean in terms of acetaldehyde anyway.

Brulosophy had a batch of 1056 swing from 19 to 30°C up and down a few times and got some off flavours from it but no acetaldehyde and nothing majorly horrible. I wonder if the liquid strain was a little more resistant than a dry strain - though I don't recall ever getting much/any acetaldehyde from US-05.

It's a hypothesis. I'm not saying that dry yeast with rock solid temperature will produce acetaldehyde, I'm wondering if due to the drying process, due to perhaps being optimistic about cell count, dry yeast - or just MJ's? - is not as resistant to non-ideal conditions as liquid strains.

why is your temp swinging so wildly?
im using an incandescent bulb as my heat source but i painted it with black stove paint and let it cure by leaving it on for a day (lots of fumes came off it) and i only get temp variations of 0.3c which is the minimum i can set my stc to. ive only been using dry yeast but have never had major issues with acetaldehyde.

Yeah I've got a Keg King controller. It's got an SS thermowell which creates a bit of lag in picking up the temperature. When it's just heating or just cooling it's fine, but I've probably had the hysteresis set too finely when freezer and heating are both on.

Stright from the BJCP website (lol BJ)
Characteristic Possible Solutions
Acetaldehydefresh cut green apples Make sure fermentation is vigorous using healthy yeast. Allow full attenuation. Leave beer on yeast longer. Oxygenate wort fully. Try another yeast strain. Make sure sufficient yeast nutrients are available. Let beer age longer.p

Thanks.

 

[MHB]

Couple of points
First up please don't read/quote Brulosophy, they aren't a reliable source and that's putting it very gently.
Yeast is temperamental, if you are going to brew Ale and you don't have good temperature control pitch and ferment around 18-20oC, nearly all Ale yeast will preform well in this range, couple of exceptions being Saison and Kölsch.
Put a small fan in your fermenting fridge, it will keep the temperature more consistent, provide some gentle heating at need, and will keep your ferment closer to the set point. remove all other heaters (belts, plates, light globes...)
Always look up the manufacturers recommendations for pitch rate, fermenting temperature and how/whether to re-hydrate. Poor re-hydration practice can kill or cripple a lot of the dry yeast, if you off half the dry yeast, no surprise if preforms worse than a liquid yeast.
In my experience/opinion both Dry and Liquid yeasts preform equally well if treated appropriately. The only reason to chose one over the other is available strains, I don't think there is a dry Hefeweizen as good as some of the liquid cultures, so would choose a liquid for a heffe, same for Saison and Kölsch. For most production beers quality dry yeast is fine I use a fair amount of S-04.

Odds on from what has been posted so far the problem is really a lot closer to home than the yeast maker.
Mark

 

[Adr_0]

You're absolutely right on all of those points Mark. MJ's do recommend rehydration, one pack for 23L of (presumably standard wort) and both packs were rehydrated together to form a nice bubbly cream - so I think the rehydration went well - and pitched into 23L of 1.040 wort. Dechlorinated tap water, "not cold" and stirred frequently. I'm not denying my poor practices are 90% of the problem - in the last few years I've only really had acetaldehyde 3 times, and each time has been dry yeast using the heating lamp - but most of the time the beers are fine.

I'm basically saying that yes in these instances I've had bad practices, but I've used a heating lamp at other times and have had no such problems making me think that these yeasts aren't as tolerant of poor practice as liquids. You said "both Dry and Liquid yeasts perform equally well if treated appropriately" which is no doubt true but perhaps dry yeasts need a little more than just rehydration to get on a level playing field? I'm keen to try it again starting at 18.5 up to 21/22 as I've heard good things about it.

 

[MHB]

If you are going to re-hydrate, make sure you get the temperature right (have a good thermometer) they (Mangrove Jacks) recommend re-hydrating Ale at 30-35oC, in 100mL of water and stirring for 8-12 minutes.
It is also a very good idea to "Attemperate" your yeast to the wort temperature in steps of not more than 5oC at 5 minute intervals (some people say 10oC steps, 5oC is safer).
If you had 100mL of yeast cream, add a little wort (say 10mL at 20oC), stir, wait 5 minutes, add another 10mL, stir... I use my glass lab thermometer to do the stirring and measuring at the same time. Prevents another case of yeast shocking that can kill or inhibit the yeast.
I'm often bemused (well was going to say amused... but not the right word) by people saying "they re-hydrate properly" when what they appear to mean is "chuck the yeast in some water... and cross their fingers".
Look after your yeast and it will make good beer.
Mark

 

[Adr_0]

That's an interesting point. Both dry and liquid packets I leave out for a few hours and then sit in a water bath either with starter wort or just water, then make up the starter or the rehydration mix. But only the liquid yeasts do I draw off wort from the batch and buzz it on the stirplate - the dry yeasts I just pour straight in. I of course make sure that the temperatures are close - comfortably within 10°C - but perhaps I should be rehydrating in a small flask then adding some wort.

Incidentally I'm not sure how accurate your glass thermometer is when it's only submerged an inch or two - unless you're making 1L rehydration mixes and have it 2/3 submerged as required.

 

[MHB]

Most thermometers are either total immersion or 76mm immersion, mine is the latter so it isn't hard to get 76mm of it into the yeast slurry.
Where do you get the 2/3 from, sort of thing those wholly educated on Brulosophy could come up with, wrong for both sorts of thermometer and misleading, without any foundation in fact.

 

[MHB]

PS I really hate Brulosophy
M

 

[technobabble66]

I'd be guessing the issue is the small starting population plus the temp variance.
If the temp is held relatively stable in the right range, the amount pitched from a sachet (11g?) should be fine and produce a good, clean result (even though 11g of dried yeast is a relatively small starting population for a ~23L, ~1.045 beer; i think it needs to double its population a few times to reach the "appropriate" population number).
If you had a large/"appropriate" population, you'd probably be able to withstand some temp fluctuations without flaws developing in the beer.
Unfortunately i'd suspect it that you've had the combination of both a small (though well primed) starting population plus the substantial temp fluctuations.

Admittedly that doesn't necessarily explain why the liquid was fine (i'm assuming you're pitching from the (relatively fresh) vial, whereas the dry was flawed. I can only assume the additional stress of rehydrating (in general, not the specific step the manufacturers recommend) & coming back to life is what makes the difference compared to liquids.
So maybe it's that latter point that really means the other 2 variables when occurring together can produce a flawed beer.

2c

Obviously you need more practice and simply have to brew more.

 

[manticle]

PS I really hate Brulosophy
M

But haven't you read the one where they did something and no-one could tell the difference? There were like, six people, all drinking beer and NO-ONE could tell the difference. That proves it.

 

[Adr_0]

Most thermometers are either total immersion or 76mm immersion, mine is the latter so it isn't hard to get 76mm of it into the yeast slurry.
Where do you get the 2/3 from, sort of thing those wholly educated on Brulosophy could come up with, wrong for both sorts of thermometer and misleading, without any foundation in fact.

I'm unfortunately lumped with a total immersion thermometer - but have found no visible change in reading when it's 2/3 immersed vs full and which tends to work better for me when measuring mash temperatures. My wife has temperature resistant hands but mine are very delicate. Anyway, while I was being a smartarse I was thinking we're getting into the few % level with starting to critique my rehydration method.

PS I really hate Brulosophy
M

I hope you're a fan of irony. 90% of the time I'm having a go at those guys - typically wrong recipe for what they're testing, though I think in 100% of cases their tasting group is too inexperienced - but I've floated one article here for discussion.

I'd be guessing the issue is the small starting population plus the temp variance.
If the temp is held relatively stable in the right range, the amount pitched from a sachet (11g?) should be fine and produce a good, clean result (even though 11g of dried yeast is a relatively small starting population for a ~23L, ~1.045 beer; i think it needs to double its population a few times to reach the "appropriate" population number).
If you had a large/"appropriate" population, you'd probably be able to withstand some temp fluctuations without flaws developing in the beer.
Unfortunately i'd suspect it that you've had the combination of both a small (though well primed) starting population plus the substantial temp fluctuations.

Admittedly that doesn't necessarily explain why the liquid was fine (i'm assuming you're pitching from the (relatively fresh) vial, whereas the dry was flawed. I can only assume the additional stress of rehydrating (in general, not the specific step the manufacturers recommend) & coming back to life is what makes the difference compared to liquids.
So maybe it's that latter point that really means the other 2 variables when occurring together can produce a flawed beer.

2c

Obviously you need more practice and simply have to brew more.

I pitched 20g and from what I could tell of the foamy rehydration I had fairly good viability. Meanwhile the 1275 was 8-9mths old, but was built up carefully. I'm not a total idiot and do have some degree of experience - good thick krausen after 6-7hrs and fast, clean ferment hopefully reflecting that.

I absolutely take a good chunk of the blame for temperature swings but I do raise the question of cell counts in the MJ's packets. Somebody somewhere - I'll dig up the post/article - took some counts and found they were a bit short.

And I definitely need more practice with dry yeasts. Luckily the hefeweizen I've just done has perfect temperature rise and is a good liquid strain so that might turn out ok.

 

[technobabble66]

20g into 20-25L?
If so, you're right: should've been fine to resist a little temp fluctuation, I would've thought.

If 20g into, say 40L, I think my point still stands.

Edit: oh, and the liquid was carefully built up? Again, backs the idea the liquid yeast would simply be in more optimal health by the time it hits the FV.

 

[Danscraftbeer]

On swinging temp control I wonder If I've gone overboard. Thermowell in 50lt kegmenter I really do control temps now.
That means literally resisting the brew from rising itself in temp. That almost seems unnatural but that's what the commercials do?
Dry versus Liquid Yeasts I've found the dry yeasts are more hardy (if hydrated carefully). Liquid yeasts you have to build up more, more vulnerable to transport temp variations so its harder to transport with much shorter life but you get a much broader and exotic range.

 

[MHB]

But haven't you read the one where they did something and no-one could tell the difference? There were like, six people, all drinking beer and NO-ONE could tell the difference. That proves it.

Is that the one where someone shat in the kettle......
Mark

 

[paulyman]

But haven't you read the one where they did something and no-one could tell the difference? There were like, six people, all drinking beer and NO-ONE could tell the difference. That proves it.

Must have missed that bit. I only read the part of the article where they analysed the results looking for some deeper meaning anyway.

 

[contrarian]

But the plural of anecdote is data, everyone knows that!