Slow start to fermentation?

[benna]

Hello,

Haven't been on here in ages, I'm a bit of an occasional brewer I'm afraid! So I made some beer yesterday, cooled it down to about 28c and pitched the yeast, some of this M79 from Mangrove Jacks (https://goo.gl/69rJCX). I've never used it before, I normally stick to S04 and US05 but thought I'd try something different as it seemed like a good fit for the brew. Anyway I must have pitched the yeast at about 5.45pm (not started off just sprinkled straight in, as I normally do) and still no signs of any activity almost 18 hours later. What should I do? Just wait or should I get some more yeast and pitch that. I can't imagine it was too hot but maybe it was a duff batch, does that even happen? Either way I really don't want it to get infected, it smells so good!

Thanks in advance for your help!

Ben

[Jocky]

I'd leave it. Yeast without a starter can take up to 36 hours to show signs of activity.

[Rhodesy]

As Jocky said, it can take some time. I seen a big different to sprinkling in dried yeast to rehydrating. There is a lot of reading on it however it is recommended to always rehydrate dried yeast as it allows quicker growth. I know the panic you can get when 12 hours later there is no activity but give it another peek tonight then again tomorrow, should hopefully see activity then.

[benna]

Yep OK. thanks for the advice! You've put my mind at rest, for now! It seems as though the yeast is kinda gathering together. Next time I will rehydrate the yeast to begin with. I'll let you know how it progresses...

[Rhodesy]

Always learning in this game which is part of the enjoyment. Making sure the wort is well aerated prior to pitching also makes a big difference.

[benna]

Ah yeah that could be an issue, I didn't aerate it. Normally I run it from the boiler into the fermenting bin from quite a height which seems to aerate it quite a bit but yesterday I put some hose on the end of the tap so that it siphoned better, this would have minimised the aeration. Should I stick a paddle on the drill and aerate it now or is it best just to leave it now??

[rpt]

Just leave it. Aeration not necessary when using dry yeast.

[hazelbrew]

Just leave it. Aeration not necessary when using dry yeast.

?!

leave it now because the growth phase is over and it is presumably fermenting away.

when you do another brew make sure to
1. aerate the wort...
2. rehydrate the dry yeast.

[Padalac]

There are quite a few brewers who believe that, if you are using dry yeast, you don't need to aerate. Myself included. Relax - this a good thing - it makes your job easier!

The explanation is simple - dry yeast is propagated aerobically, whereas wet yeast is propagated in wort. You definitely do need to aerate with wet yeast. If aerating is not necessary with dry yeast then why do it? All you're doing is introducing whatever extra bacteria, spores and wild yeasts floating around in your environment into the beer.

From personal experience, I've had better results NOT aerating when using dry yeast. I'm currently brewing a monster high gravity porter, with an OG of 1.096. Did I aerate? Absolutely not. I'll let you know how it turns out. As far as I'm concerned, if that thing ferments out to 80% or so, and tastes clean, then you can just forget aerating with dry yeast. The ones I've tried without aerating so far have turned out great up to around 1.060 OG, but I haven't tried any higher gravity until now.
Rehydrating dry yeast on the other hand... Absolutely worth it in theory and in my experience.

[benna]

Thanks for the info re. aeration, I didn't know that about dry / wet yeast before. As I say the only aeration I've ever done before is in the transferring of the wort from the boiler to the fermenter and it's always worked alright for me in the past. It's still not really going for it yet, 24 hours later, but as I say the yeast has all clumped together and it does seem a bit co2ey. What happens after 36 hours if it doesn't get going? Pitch more yeast?? Hydrated this time...

[MTW]

Just leave it. Aeration not necessary when using dry yeast.

There are quite a few brewers who believe that, if you are using dry yeast, you don't need to aerate. Myself included. Relax - this a good thing - it makes your job easier!

The explanation is simple - dry yeast is propagated aerobically, whereas wet yeast is propagated in wort. You definitely do need to aerate with wet yeast. If aerating is not necessary with dry yeast then why do it? All you're doing is introducing whatever extra bacteria, spores and wild yeasts floating around in your environment into the beer.

From personal experience, I've had better results NOT aerating when using dry yeast. I'm currently brewing a monster high gravity porter, with an OG of 1.096. Did I aerate? Absolutely not. I'll let you know how it turns out. As far as I'm concerned, if that thing ferments out to 80% or so, and tastes clean, then you can just forget aerating with dry yeast. The ones I've tried without aerating so far have turned out great up to around 1.060 OG, but I haven't tried any higher gravity until now.
Rehydrating dry yeast on the other hand... Absolutely worth it in theory and in my experience.

That's not always the case. In beers above 5% ABV, it is recommended that you aerate, when using dry yeast. The aeration doesn't hurt, so if it's close, I would aerate.

[rpt]

As pointed out, aerating can do harm. So can rehydration. If you can't do these in a sanitary way (and at the right temperature in the case of rehydration) then you shouldn't do it.

What happens after 36 hours if it doesn't get going? Pitch more yeast?? Hydrated this time...

To know if anything is happening, you must use a hydrometer. Lack of visible activity doesn't necessarily mean nothing is happening, especially if you aren't familiar with that particular strain.

[BrannigansLove]

Doesn't seem to have been mentioned previously, but 28c seems a bit high to be pitching yeast into. It probably hasn't killed the yeast, but I always try and get down to at least 22c (maybe a bit higher for saison yeasts) before I pitch.

[Fil]

Doesn't seem to have been mentioned previously, but 28c seems a bit high to be pitching yeast into. It probably hasn't killed the yeast, but I always try and get down to at least 22c (maybe a bit higher for saison yeasts) before I pitch.

It should be fine, when growing yeast populations up in a flask/starter warmer than optimum fermetation for flavour temps are common, and if the wort is cooling down pitching into warmer wort with a sprinkle of dry yeast is fine imho,

when fermenting in my jerrycans with limited headroom i pitch dry yeast onto a minimally aerated wort, it does limit the initial kraussen but in the brewfridge fermentation will still complete in 5days with a OG 1044-1055

[benna]

Well the OG was 1047 and it seems to be down to 1043 now so it's obviously doing something, maybe it is just the strain, but it's weird because it just seems to have these big blobs of yeast. I have it in a standard fermenting bin with an airlock and the airlock is basically doing f all, but it's definitely air tight and pressured because when I put the lid on it bubbles and it does occasionally bubble. Anyway we'll see what's going on tomorrow. I need to stop bloody looking at it! I had a batch go off before infact two brews ago, I was a bit slack with sterilising a sieve I needed in an emergency when the hop strainer came off, it was so depressing because it is a lot of work. I just need a permanent set up and no kids (!) so I can brew more often - and drink more often.