Reusing US-05

[Bridges]

Wild yeast is everywhere. I thought it was all about making sure that the yeast we want is the dominant strain in the fermenter. The biggest kid in the schoolyard so to speak.

 

[damoninja]

Well, I just harvested a pint of US-05 slurry (swirled the fermenter after kegging) from a 1.045 OG apa fermented at 18.5C and pitched it into a new batch of 1.055 apa (21L in a 30L fermenter) and in under 24 hours the krausen was gushing from the airlock. A good litre has bubbled out.. madness.

I'm glad I didn't pitch half the slurry! I do however think it might have something to do with the fact that it was out of the fermenter in 8 days (i needed beer damnit) so was probably extra lively.

Al

Sounds like there's a fair chance of my fridge having a big mess in it!

Would it be wise to start the temp a little lower say 16-17 degrees?

 

[of mice and gods]

I can't really comment damoninja, i'm not really au fait with yeast pitching.. I mainly just kick in a pack of safbrew something. The pro-yeast rinsers and cell counters would probably be able to give a more comprehensive answer.

What I do know is I've previously pitched cubes straight onto the entire slurry of previous US-05 batch and had big krausen at 18.5C but nothing like this. Maybe if I'd left it to ferment or cold condition for longer then 8 days the yeast response would have been less dramatic. I'm sure the other times I re-pitched the existing yeast had been in the fermenter for about 2 weeks.

Al

 

[hoppy2B]

Why? Just because the hops have been pelletized I shouldn't think that removes the wild yeast/dust/spores that would have been present as whole cones.

Yeah, the point I was trying to make is that they must treat hop pellets in some way so as to avoid bringing hop diseases into the country because I doubt that just pelletizing the hops would kill the organisms responsible for hop blight etc.
Which is to say that T90 pellets either have chemicals added or they are irradiated or something.

 

[hoppy2B]

And as a hop specialist I thought Yob might know of these things. :unsure:

 

[damoninja]

I can't really comment damoninja, i'm not really au fait with yeast pitching.. I mainly just kick in a pack of safbrew something. The pro-yeast rinsers and cell counters would probably be able to give a more comprehensive answer.

What I do know is I've previously pitched cubes straight onto the entire slurry of previous US-05 batch and had big krausen at 18.5C but nothing like this. Maybe if I'd left it to ferment or cold condition for longer then 8 days the yeast response would have been less dramatic. I'm sure the other times I re-pitched the existing yeast had been in the fermenter for about 2 weeks.

Al

Oh - entire yeast cake... Think this is what the guys were previously referring to as a runaway fermentation.

I'm taking Yob's advice and using considerably less ^_^

 

[Alex.Tas]

although a completely different yeast strain, I started a topic yesterday about reusing wyeast 3068, i got the consensus that reusing the whole yeast cake for an identical brew gave far less flavour. Would the same apply to this strain of yeast?

 

[DJR]

Yeah, the point I was trying to make is that they must treat hop pellets in some way so as to avoid bringing hop diseases into the country because I doubt that just pelletizing the hops would kill the organisms responsible for hop blight etc.
Which is to say that T90 pellets either have chemicals added or they are irradiated or something.

They are not chemically treated or irradiated. Just go through a pelletizer, which compresses them (therefore heating them up and killing anything) and I think then they basically are rapidly chilled as they get turned into pellets, which then keeps them that way, then they are packaged and stored under CO2 so no oxygen for nasties to live in.

Go ahead and make a beer and see how you go, AFAIK hops have anti bacterial properties, yeasts might still be around in pellets/whole hops but remember they might not be saccharomyces type yeasts, could be candida, brettanomyces, etc. Either way, I think it's better just to use the very wide variety of good brewing yeasts available than waste money and time making hop wild yeast beer.

 

[DJR]

although a completely different yeast strain, I started a topic yesterday about reusing wyeast 3068, i got the consensus that reusing the whole yeast cake for an identical brew gave far less flavour. Would the same apply to this strain of yeast?

Yep, thats because yeast needs to grow to add flavour particularly for wheat beer style flavours e.g. iso amyl acetate (banana), clove (4VG), these are generally formed by yeast growth/lag phase and if the yeast is already high enough in cells then the yeast will go straight to attenuative phase, not grow, and not add much flavour at all. That's why you only take 1/3 or a 1/2 of the yeast cake and repitch. In a commercial brewery they'll use the racking port to remove a lot of the yeast from the bottom or all, and then repitch with fresh yeast even though you'll hear of them repitching over and over.

Repitching onto a whole cake might be useful sometimes though, e.g. pitching huge beers >1100 OG and if you want to do really lager-like ales

 

[Byran]

I think that reusing slurry is great its just a timing thing.

I have found that if storing yeast slurry in the fridge you will end up with autolysis after a given period of time. ( The yeast cells eat themselves away due to lack of nutrients I think? eg vegimite flavour). I have found that healthy stored slurry can benefit greatly from adding sterile wort to the container instead of water before storage in the fridge. I reuse Whitelabs vials for this because they can handle the pressure, just crack them every week or so to let out the gas pressure. Ive have stored tiny amounts of yeast for months and months in the fridge with no degradation to the startup quality or ferment flavours when making a starter in the future. Sort of like simple yeast slant stuff without all the bullshit.

Ive repitched every yeast ive ever used many times over from slurry and it seems to work quite well if you use the basic 50mls ale slurry for 23l 1.050 wort, 100mls lager slurry for 23l 1.050 wort rule. Mr maltys calculator shows this quite clearly and I have had heaps of trouble with over under pitching until I took this into serious consideration.

I reused a 1469 slurry for about 12 batches over about a year with no probs at all. I just wanted to try a new yeast so i turfed the remainder. That yeast was probably isolated from a brewery in England where they were reusing it for a long, long, long time without a lab.

Bottom line is if it doesn't taste nice as a slurry, it might not be right to reuse.

 

[wbosher]

I like Nick JD's method (am I allowed to say that? h34r: ) of pouring 600mls slurry into a PET bottle. Will eventually sink to the bottom covered with beer. Then pour off and drink the beer before pitching yeast.

 

[of mice and gods]

Oh - entire yeast cake... Think this is what the guys were previously referring to as a runaway fermentation.

I'm taking Yob's advice and using considerably less ^_^

If you look more closely bro I only used about 500mls this time and had a krausen volcano. Where as previously I've pitched on to the whole yeast cake and never had a volcano. So the point I was trying to make was maybe leave the beer in primary for more than a week before harvesting your slurry.

Al

 

[damoninja]

So, I've pulled ripped the cake outta the FV and put into some sterile bottles (there was SHITLOADS).

It's been sitting for about an hour and hasn't really produced the strata I expected.....




Should I pitch any parts of this? Or one of the whole bottles? Or abandon and use a fresh pack?

I've got 18 minutes left on my boil, then chill and whack it in the FV.

 

[technobabble66]

What happened? What did u do?

Looks like a great amount of reclaimed yeast cake. Bit odd it's all white!? Did it settle out & stratify?

 

[damoninja]

What happened? What did u do?

Looks like a great amount of reclaimed yeast cake. Bit odd it's all white!? Did it settle out & stratify?

It's veeeery slowly settling to form a thin layer of lighter yeast on top... But pretty thin...

I've spread it out into a few smaller bottles and I'm putting it in the fridge (no point wasting it) see if it's salvageable

 

[technobabble66]

Sorry - of no help. Never done the yeast cake thing. Hoping to do it with the cake when bottling in the next few days.
At a guess the bottle on the left or right might b ok to pitch straight in.
What's Yob estimate? 200ml cake slurry into each bottle. That equates to vaguely enuff yeast slurry in the rinsed bottle to pitch straight into the FV. Sound right?

 

[damoninja]

No worries - I don't doubt that pitching part of this might have been OK but I don't want to go overkill this one with trub, I can see it producing a lot being a slightly bigger beer than I have been brewing.


:icon_offtopic: 155 grams of hops in 25 litres is nuts! As they're setting there's like a foot of thick hoppy goodness ^_^ will have to be like a half inch of hops when it's done.

 

[Yob]

The bottle on the left looks to have almost the right volume of slurry ratio, is it being done at room temp?

I find that the taller and thinner the jar, the better the separation. I've got to rinse some Greenbelt in the next day or so And will make sure to take a couple of relevant piccies for you.

 

[damoninja]

The bottle on the left looks to have almost the right volume of slurry ratio, is it being done at room temp?

I find that the taller and thinner the jar, the better the separation. I've got to rinse some Greenbelt in the next day or so And will make sure to take a couple of relevant piccies for you.

Room temp, kitchen was 22 degrees at the time... I've started collecting passata jars but way underestimated the amount of trub that I would have...

This was my first cold crash, so I'm assuming there's sediment caused by this?

 

[Camo6]

I keep a collection of pasta sauce jars for the same reason. I bought a $50 electric pressure cooker from Aldi and can sterilise around four jars at a time. Then tip one or two onto yeast cake and recover into the same jars. Top up with another jar, rinse, repeat etc etc. I've also been sterilising the odd jar of starter wort for topping up stepped starters without having to do a small boil first. Just got to remember to leave all the lids loose in the cooker and wear protective gear when handling. And let them cool slowly.