Bitten off more than I can chew - Doppelbock - Karla

[GordonD1980]

I think i may be trying to run a bit soon. I've been all grain brewing for two years, custom 2 kettle setup. Mostly knocking out America IPAs, light ales and a few clones like Gamma Ray. Simple, quick and great results, I fancied something different and got the Doppelbock - Karla recipe kit, from The Malt Miller.

The guide's water bill doesn't add up - 19ltr mash. but no mention of sparging or liquor back volume and a final post boil target of 20ltr. But thats not the worry, I think i can wing that.

The bit that gets me worried is the yeast. The kit came with a single WLP 833 German Bock. so say 100b cells, from what I get from the calculators for 20ltr of 1.079 i need closer to 700b. I've only ever done a small starters to kick start, but no idea how to ramp 7x, do i really pitch 4ltr of a starter? or what the real impact on under pitching? Or have I just got it wrong.

Any tips or guides i should be reading?

Many thanks
Gordon

 

[BeerCat]

The problem with under pitching is that in can cause of flavours or simply not finish fermenting. I would make up a 1l starter. Then decant the wort and step it up to 3l. Decant again and pitch. Save a little of that for your next brew. WLP833 is a decent yeast. I presume you have temp control?

 

[GordonD1980]

Thanks BeerCat.
I've got modified fridge with Inkbird and a heatmat, although its about to have a IPA in there. Getting a second setup built this week.

As far as timing for each step of the starter, do you wait until the yeast drops out of suspension? how do you spot that if using a stir plate? How long would each step typically take?

Cheers,
Gordon

 

[BeerCat]

In a moderate temperature and with fresh yeast each step can take as little as 24 hours. I have had packs take 2 days to do anything but got going in the end. I leave mine 2 or 3 days between each step as I try not to rush and my house is cold.
You should know it's done as it will clump together at the bottom. If not sure try the starter and take a gravity reading.

 

[GordonD1980]

Thanks,
First step done a few hours ago. I pitched at 20C. For the main brew it suggests 18-20C for the first 5 hours, or until it looks under way, then to chill to the optimum for the style 8-10C. Does that matter so much for the starter? or is 18C what you class as moderate Temp?

 

[foxbat]

20C is fine for starters and is what I use. You're trying to grow yeast not make beer so warm is good to encourage the reproductive phase.

I pitch lagers as close to 10C as I can get in reasonable time - usually ends up being 12 or so the morning after brewday. Then it's 10C until I notice peak fermentation is over, then up a degree or so a day to 16C where it stays until 3 weeks after pitching.

 

[GordonD1980]

Thanks for all the help. Beercat + Foxbat.

My second step should be up at over 600B cells :-). I also got my self a stirplate.. I'd say less than 30min after pitching into the second step, the yeast was really active great seeing all the micro bubbles of CO2 thought the glass. 18hours on the Stir plate and Im now letting it settle. Brewing the Dopplebock tomorrow morning, so by the time thats down to temp the starter should be ready!.