RIS with yeast slurry, still waiting for takeoff

Northern Brewer General
1

I harvested a Wyeast 1728 yeast cake from my Scottish 70 (1.04 OG) on Monday (sterilized the jars by boiling before and then let them cool but didn’t use Star-San) and pitched approx 8-10oz into my RIS wort at 68F. As it’s in a swamp cooler the temp of the water is stable at 59F.

By all accounts I have read, with a RIS (1.09 OG) and re-using freshly harvested yeast slurry I should have had minimal lag time and an explosive fermentation so I attached a blow-off tube. Now 36 hours later, and there are no signs of activity in the bucket (krausen or blowoff).

Is the high OG a cause for this delay? Or did I cause the yeast to go dormant/die (thermal shock?) by pitching at 68F when they were around 78F air temp and are now roughly 59F?

Should go out and buy some dry yeast and re-pitch? Will using two different yeast strains (the 1728 and a dry yeast like S-04 or Notty) create problems?

Thanks

2

[quote=“tj218”]

Is the high OG a cause for this delay? Or did I cause the yeast to go dormant/die (thermal shock?) by pitching at 68F when they were around 78F air temp and are now roughly 59F?

No

Should go out and buy some dry yeast and re-pitch?

I don’t think so.

Will using two different yeast strains (the 1728 and a dry yeast like S-04 or Notty) create problems?

No

Thanks[/quote]

How long was the yeast in the other fermenter? Even though it’s “fresh”, if it sat for 2 weeks after active fermentation you could see some lag time.

3

Thanks for the quick reply!

The yeast sat in that primary for 3 1/2 weeks (pitch date: 7/13) and active ended about 2 1/2 weeks ago.

How much lag time should I expect then? I just swirled the fermenter to see if that will help.

4

Lag time can be up to 72hrs or so. I bet it starts showing signs today… tomorrow at the latest.

RDWHAHB :cheers:

5

This is literally the exact scenario, albeit with different beer and yeast, that I had this weekend. The fermentation eventually took off after a while, but never got explosive. Let it ride. It’ll be fine.

6

This is why I always make a yeast starter even with my slurries, not matter how long they have set. I have never had good luck just pitching a slurry.

7

At 51 hours and the OG hasn’t budged. I was under the impression fresh slurry didn’t need a starter. :frowning:

If I don’t have anything tomorrow I am going to the LHBS to buy some dry yeast. Would S-04, S-05, or Notty be better for a RIS? Should I pitch two packets or do I risk the slurry yeast also waking up and causing a massive overpitch?

8

At 51 hours and the OG hasn’t budged. I was under the impression fresh slurry didn’t need a starter. :frowning:

If I don’t have anything tomorrow I am going to the LHBS to buy some dry yeast. Would S-04, S-05, or Notty be better for a RIS? Should I pitch two packets or do I risk the slurry yeast also waking up and causing a massive overpitch?[/quote]

62 hours in, still nothing. Gave it a shake. I can’t believe all that yeast is dead. I’m now also worried about the Scottish 70 (where this slurry came from) and whether or not there was enough yeast left for carbonation…

9

Woke up this morning still had nothing. I decided to shake it (basically picked it up twice and lightly jostled it) since I realized I didn’t shake it after I threw in the slurry. Within 30minutes I had bubbles in the airlock, one every 6 seconds. This continues 12 hours later but the pace has picked up. Could just be a coincidence but the fact the rate has sped up is promising.

Holding off on the dry yeast for the next day.

10

The yeast did their job with the last beer and went into dormancy.

They had to wake up, regroup and get back to work. Unfortunately it doesn’t happen over night.

If you can time a starter to be finished, or something small like 2-3 cups for a slurry, so you can pitch it right away you then could see fermentation starting within a few hours.