Yeast/Fermentation Question

[hawker831]

Hi all,

 

Just a quick question. I'm currently brewing the School of Hops ROTM which calls for the wort to be 18-20 degrees and with a different type of yeast (not the standard Coopers one).

 

It's been nearly 36 hours since I added the yeast and not much seems to be happening (yeast has absorbed liquid and turned to goo and a few bubbles. I realise that because the wort is cooler than what I usually have it (around 24) that the yeast will take longer to get started, however I just wanted to know how long I can leave it there until I start to worry that the yeast isnt doing anything?

 

Thanks

[Titan8]

What yeast did you use and how much? Dry pitch or did you rehydrate? Some yeast can be slow starters so would not be overly worried at this stage.

[hawker831]

Hi Titan,

 

It was 11.5g Safale US-05 Dry Yeast, I dry pitched didnt hydrate. Well see what happens over the next 12 hours or so. Fingers crossed.

[Corksniffer]

I'm with Titan. US05 has taken up to 2 days to show any real vigour for me, even in hot temps. If you're seeing the odd bubble for now you're set

[Quokka]

Agreed, either pitch at a higher temperature, use a starter, or wait - but I worry too much about infection if it takes more than 24 hours, so I usually choose one of the first two. That's just me.

 

[Otto Von Blotto]

Sometimes US-05 is pretty subdued in terms of visual activity. It may well be fermenting, or getting going. I often get lag times over 40 hours with lager yeasts, mostly due to pitching them at 10C probably, but never have any infection problems. I wouldn't stress too much yet, if it gets to 48 hours take an SG reading before deciding on any rescue action.

[Quokka]

Infection is less likely at 10 than 18C, but I was actually suggesting I'm a little anal about it. I do think a good starter is a good idea if fermenting at low temperatures, or starting a few degrees higher for the first 12-24hours.

 

In fact I have just built a stir plate - 30C all week, but I could stick it in the wine cooler...

[hawker831]

So its been about 48 hours now and it definitely looks like there's some action going on in there.

 

Wort is a bit cloudy and there is a 5mm layer of foam. A lot less than I'm used to but I guess I'm looking at a 'slow burn' for this one.

 

Will see how it looks in another 12 hours.

 

Thanks for your help guys.

 

[Quokka]

You'll be fine.

 

I use the SA-04 more often and I like to pitch while the wort is still quite warm when using dry yeast, but the yeast is good. What you have been seeing is most likely the yeast breeding up to the 180 billion or so it needs which has probably taken a little longer than usual due to your temperature and possibly a lack of oxygen in the wort. 48 hours to Krausen with a dried Ale yeast is not that uncommon though, and I wouldn't panic yet (well I might, but I have some Valium and I'd get over it.)

[Beefy1525229962]

It was 11.5g Safale US-05 Dry Yeast' date=' I dry pitched didnt hydrate. Well see what happens over the next 12 hours or so. Fingers crossed.[/quote']

 

Of my last few brews, I dry pitched S-05 twice, and rehydrated/pitched twice. With dry pitching it really takes off at about 48-72 hours. Rehydrating 24-36 - literally half the lag period.

 

So I strongly recommend rehydrating dry yeast - if only to speed things up, and to let you know if there is a problem earlier!

 

[tire38]

It was 11.5g Safale US-05 Dry Yeast' date=' I dry pitched didnt hydrate. Well see what happens over the next 12 hours or so. Fingers crossed.[/quote']

 

Of my last few brews, I dry pitched S-05 twice, and rehydrated/pitched twice. With dry pitching it really takes off at about 48-72 hours. Rehydrating 24-36 - literally half the lag period.

 

So I strongly recommend rehydrating dry yeast - if only to speed things up, and to let you know if there is a problem earlier!

 

Put together a brew last night and used US-05 for the 1st time, rehydrated before pitching. This morning the airlock is bubbling over. I know you guys say don't look at the airlock but in my eyes a bubbling airlock is a happy airlock!

[Otto Von Blotto]

It's underway, so you should be fine. The krausen may or may not increase in size from here; my experience with US-05 over the years is that it's not volcanic so it'll probably get a little bit bigger but you won't be cleaning up a mess.

 

Yeah, I make starters for all my batches now because I prefer to pitch the recommended amount of cells (approximately anyway), and I also harvest yeast from them for re-use. The lag time is actually longer when there is more oxygen because the yeast are using it up before they get going. I oxygenate my wort these days and I've noticed the lag times increase from about 8-12 hours up to 20ish hours. The fermentations are done quicker though.

 

In reality it should have been pitched with 180-200 billion cells, which would multiply to 4 or 5 times that to ferment the batch. Dry pitching allegedly kills up to half the cells, so depending on how viable the yeast were to begin with, that probably explains the long lag time. If you're killing up to half your starting cells before they've even had a chance to do anything then it's gonna take longer for the ones that survived to multiply to the numbers needed. I can't say I've ever experienced a lag time that long with US-05 before, even before I was making starters, regardless of whether it was pitched at ferment temps or pitched warmer.

 

I only dry pitched it once, on my first ever AG batch. It got going in about a day, but I decided to re-hydrate after that because I didn't like the idea of the dry yeast sitting on top of 6 inches of foam for however long that took to subside. I figured it was better to get the yeast in there more quickly.

 

Cheers

 

Kelsey

[headmaster]

After more than ten generations of re-using my US05, I used a new packet for my current brew, a US pale ale, all grain OG1050 late addition only cascade centennial based, dry hopped with cascade centennial and a bit of galaxy.

 

I rehydrated it using the exact method prescribed by Fermentis, and pitched into wort that had been chilled to exactly 18c in a brew fridge (while in the cube) then poured from a height into the Coopers FV.

 

So the re-hydration method was, sprinkle yeast onto cooled boiled water about 150ml, in small coffee plunger beaker (that I used to boil the water in, foil over top, stir bar in) water at 27c. Let sit for 30 mins, then put on stir plate for another 30 mins, stirring very slowly.

 

Poured a few litres of wort into FV, then poured in yeast, then poured in the rest of the wort, approx 23 litres in total, about 10pm last tuesday evening. Next day in the morning no real sign of activity apart from condensation under lid. By about 2pm though there was 1mm krausen so 16 hrs. By 24 hrs was 1cm krausen. was at 1010 friday morning, almost finished.

 

US05 pack expiry date was out to something in 2018 from memory so quite fresh.

 

So this is generally not as quick as my re-use of harvested liquid yeast but still not bad.

 

 

[Otto Von Blotto]

Interesting that they'd recommend re-hydrating for an hour when most other literature says that you don't really want to go over 30 minutes, as the yeast begin to consume the trehalose reserves (the same as letting chilled yeast warm up for hours before pitching it) and end up just as vulnerable to osmotic pressure as they are when de-hydrated.

 

In any case, it fermented the brew in 2 or 3 days so obviously it was pretty happy in there!

[headmaster]

 

Yeah the rest says 15 to 30 mins, so I guess it's 45 to 60 mins total for the procedure:

 

From Fermentis US05 datasheet:

 

Rehydration Instructions

Sprinkle the yeast in minimum 10 times its weight of sterile water or wort at 27°c ± 3°C (80°F ±

6°F). Leave to rest 15 to 30 minutes. Gently stir for 30 minutes, and pitch the resultant cream

into the fermentation vessel.

Alternatively, pitch the yeast directly in the fermentation vessel providing the temperature of the

wort is above 20°C (68°F). Progressively sprinkle the dry yeast into the wort ensuring the yeast

covers all the surface of wort available in order to avoid clumps. Leave for 30 minutes, then mix

the

wort using aeration or by wort addition.

 

[Otto Von Blotto]

Yeah, I have read that in the past. Most other instructions in relation to it suggest letting it rest for 15 minutes then stirring for no more than 15 minutes before pitching it into the wort. In reality it doesn't need to be stirred any longer than it takes to evenly mix it up. I like to use wide, shallow containers for re-hydrating dry yeast too so that more of it comes in contact with the water surface rather than it being a big dry mound on top of it.