Pitching harvested slurry + fresh starter?

[Judochop]

I’m brewing a strong lager (OG of ~1.070) 5 days from now. I have a previous fermentation from which I intend to collect the yeast slurry, and then rinse it over a few days. However, by the time I brew the upcoming strong lager, it will have been 3 weeks since I first pitched into the previous batch.

My thought was to pitch an appropriate amount of slurry (~250-300 ml) directly into my wort, and then to also add an active starter containing 1 smackpack of the same yeast strain, just for good measure. (I generally find my fermentations are better when pitching an active starter anyway).

So, thoughts on pitching a large population of yeast in sleeping slurry form, along with an active, smaller sized starter? I’m wondering if I’m looking for trouble by pitching yeast in 2 different conditions?

If that is a legitimate concern, I’m wondering if I should just put the whole population, slurry and smackpack, into the small starter together? But that seems like a lot of yeast in a small wort volume. Is there such thing as overpitching a starter?

 

[TopgunTango]

You aren't necessarily looking for trouble as the thought behind the whole thing isn't bad at all, but it is rather unnecessary to add a packet of fresh yeast. Just make a starter with the harvested, washed yeast and it will be absolutely fine.

There are no real ill side-effects to overpitching, but it will create a lot of trub at the bottom and you will lose a lot of useable beer and get undesireable (for a lager) yeasty off-flavors.

 

[edognight]

I agree with above. I repitch yeast with reckless abandon, ignoring all caution about re using yeast from a big beer, and never wash rinse or otherwise, and I have yet to have a problem.

My .02$ is repitch, get a huge dosage, and save money.

 

[solbes]

You do need an a$$load of yeast for a 1.070 lager, so a repitch will give you that. I made a maibock last winter (1.064) and did just that. Took the yeast from my Oktoberfest and washed it only once. It was almost 3 weeks in primary. The Bock took right off and was my best lager to date.

I just did the same thing with an orange pale ale into a 1.114 barleywine. That one I didn't wash, but 2 mason jars of yeast/trub right into the barleywine. I had some activity within 2-3 hours, and strong activity within 8. So there must not have been much reproduction going on. Should power through all that sugar.

No need for a fresh smack pack of yeast or starter IMO. Washing may be a good idea if you want to assure the flavor of your bigger brew does not take anything from your previous lager.

 

[Nameless_Matt]

I'm doing pretty much the same thing as you, same time scales too!

I was planning on racking my current lager off of the yeast (primary will be finished in 3 or 4 days) and then after wiping the "tide marks" away with a starsan cloth, pouring my chilled 1080 doppelbock wort right on top of the old yeast cake.

As its such a big beer, I know I'll need excessive amounts of yeast -

1.5m x °p x ml

1.5m x 20 x 22k = 660bn cells.

and with lagers whilst over pitching is still bad its not as bad as under pitching - I would rather do it this way than risk an infection by trying to get rid of the old trub.


I know it'll mean that the yeast will be unusable afterwards - but what other downsides are there to my plan?

What's the likeliness of picking up bad yeast flavours from the previous batches trub?

To what degree am I looking to be overpitching?

Cheers All

Matt

 

[Judochop]

I don't like the rack-onto-entire-cake method. Theoretically speaking, it's crazy overpitching, but even practically, I've never been pleased with the results. (eg. minor off-flavors and poor finishes). If I were to succumb to laziness and rack new wort onto a yeast cake, I would probably give the cake a thorough swirl and pour out a majority of the slurry before racking, using an eyeball's approximation to leave an appropriate amount of yeast, taking into account all the trub.

As to my original question... I already have purchased the extra yeast pack, so Imagonna use it. I think I'll just make a 1L starter with the packet and 250 mls or so of washed yeast.

 

[Nameless_Matt]

What volume is your new batch of Lager?

After a lot of reading I think I'm going to try to rinse the yeast and pitch at the correct (estimated) rate which will be about 250ml of a nice settled yeast layer.

If I can't salvage that much then I'll have to work something out

As you've already bought the pack you may as well use it if you're not planning any other brews - we can work out how much of your original yeast you'll need in addition