Suggestions for my inventory - Pale ale and stout

[Mariton]

I have some bits and pieces laying around I would like to use up. I have 2 tins of Coopers Aussie Pale Ale (just past use by date) and a Muntons Gold Imperial Stout. I also have 1kg of LDME (Muntons also) and some Lactose. I have 3 yeasts - Safale S04, the Pale Ale kit yeast and the Muntons Gold kit yeast.

I was thinking of doing the following:

- 2 can Pale Ale brew using the Safale yeast. Maybe add a little extra LDME to this brew in case it is too bitter.

- Then pitch the Muntons Gold Stout onto the yeast cake of the finished Pale Ale afterwards. Again adding a little LDME plus about 100g of the Lactose.

So my questions are:
- Is it ok to pitch the stout onto the pale yeast cake?
- Has anyone tried using a combination of yeasts (ie. the Safale and the Coopers kit yeast into same brew)?

Cheers.

[timmy]

Hi,

You should be fine re-pitching the stout onto the previous yeast cake provided your sanitation is good. The combo of yeasts probably won't do what you're expecting - one will generally take over (at least that's what the consensus is around here).

Cheers,

Tim

[Jacko_NZ]

When you pitch on to an existing yeast cake do you have to do anything special with the cleansing? Usually once I finish bottling a brew there is a ring of scum around the top of the fermenter where the krausen was, is it ok to leave that or does it have to be cleaned? If so don't you risk cleaning products getting into that yeast cake?

[warra48]

I have repitched straight onto the yeast cake on a number of occasions, and do it without cleaning the fermenter.

Alternatively, you might be better to scoop out a sanitised jar or two of the cake from the bottom of the fermenter, then clean and sanitise your fermenter. Once your wort is in there, then pitch the harvested yeast.

Some brewers will say that pitching onto a full yeast cake is effectively overpitching, which problem you'll avoid if you harvest it first, and then repitch.

[Trough Lolly]

...Some brewers will say that pitching onto a full yeast cake is effectively overpitching, which problem you'll avoid if you harvest it first, and then repitch...

I've seen this line a few times and I personally have a problem with the logic behind this comment. Overpitching implies that too much yeast has been made for the wort to support and possibly results in unintended flavour consequences. Why?

The yeast cake was ok for the previous batch, so it should be fine for the next batch (I'm ignoring the infection argument here as it's not relevant when we're talking about overpitching, not sanitation).

Sure, there will be some tired/stressed and possibly mutated yeast that may not be too good but rather than plating out the cells and trying to avoid those cells, our micro levels of brewing should be fine for the yeast in the fermenter. The overpitching argument would be further supported if the fresh wort resulted in the yeast going back into an adaptive phase and further generated additional yeast cells. This logically could result in an excessive cell count in the wort. The problem I have with this theory though is that all of my repitched worts take off in minutes, not hours. This very low lag is due to the vast majority of cells in the fermenter being active, viable and ready to attenuate anything within cooee of them that has sugar present. It's this theory that has allowed breweries all around the world to use the same yeast for decades in their fermentation process.

The main reason why we have avoiding repitching more than 3 times is the substantially increased risk of cell mutation and infection from the substantial trub levels in the yeast cake, not excessive quantities of fresh yeast in the fermenter. If you have a healthy yeast cake, there's no need to aerate the wort at all - the yeast are ready to commence anaerobic fermentation of the sugars from the moment you pitch the fresh wort onto them. I don't have scientific evidence to support my comments, but I do repitch regularly, and every time the second batch is better than the first and (touch wood) I have not had an infection in 13+ years of brewing.

I have avoided going into "geek mode" on this but I'd be happy to hear from those who are certain that the yeast cake from one batch of beer is excessive for another batch of wort...

Cheers,
TL

[drsmurto]

Yes and no.

I have done both and it depends entirely on the yeast in question.

Sorry to continue to drag this topic way off track but...

A lager i am happy to repitch onto the entire yeast cake, particularly as i like to pitch at ferment temps so i need more yeast if you pitch at say 22 and slowly cool to ferment temps over 24-48h.

For an english ale i am more inclined to split the yeast cake into 3rds. i find that if i 'overpitch' for lack of a better definition the esters that i really want the english ale yeasts to produce can be a tad muted.

But then if i start on a low grav bitter and ramp it up to an ESB or old ale or porter etc i will happily repitch onto the entire yeast cake.

Just my experiences to date.

Cheers
DrSmurto

p.s. I dont repitch onto dry yeast cakes as they are just too cheap except for the US05 cake i was given just before xmas which was used to ferment a barleywine. Someone has to take on GMK in the barleywine category at SABSOSA and ANAWBS!

[Mariton]

Well I have gone ahead and put down the two cans of coopers pale ale with no additions. Ended up using the Safale s04 - pitched at around 22 degrees and been bubbling away nicely for two days at around 20 degrees. Once I bottle this I will give it a shot - that is pitching the Muntons gold 3kg stout kit onto the yeast cake and see how it goes. Still might add a little LDME and Lactose to the stout to use up some of my old gear.

Cheers

[Trough Lolly]

Someone has to take on GMK in the barleywine category at SABSOSA and ANAWBS!

I have a stubbie of Kenny's first ever barleywine in my cellar - I'll put on the asbestos gear and try it out one day!!

[Mariton]

Just bottled the toucan Coopers Pale Ale. Tasted bloody good out of the vat - not too bitter at all. 14 days @ 18c.

Put the muntons gold imperial stout straight down on about half the S04 yeast cake (scooped half out with brew spoon). It was one of those 3 kilo kits and just added a little lactose and 200g LDME. Fingers crossed she goes ok.

Cheers