Bavarian Hefe as a starter for a Weizenbock

As summer is coming up, and I'm pretty well stocked with Blondes, Pales, IPAs, and IIPAs....it's time to get some wheat beers moving!

My question is this: Is it a bad idea to kick things off with a bavarian style hefeweizen and then pitch a much bigger weizenbock onto the cake after primary is over?

The reason I'm even asking is because I am sure that a lot of the banana / clove / phenolic flavor of a bavarian wheat is due to the yeast being stressed. Overpitching would provide a much less stressful environment and probably reduce the yeast flavors significantly and possibly even detrimentally...right? Maybe I should wash the cake and pitch only a portion into the new batch?

Here are the recipes I'm planning, and they're basically my (over?)simplified versions of Franziskaner (my favorite bavarian hefeweizen) and Aventinus (my favorite Weizenbock):

Bavarian Hefeweizen
Size = 5.5 gal
OG = 1.049-1.051
FG = 1.010-1.012

8.5 lbs. Wheat Malt
3.5 lbs. Pilsen

12 IBUs from Hallertauer

Ferment with Wyeast 3068 @ 64F for two weeks


Weizenbock
Size - 5.5 gal
OG = 1.073-1.075
FG = 1.018-1.020

9 lbs. Wheat Malt
6 lbs. Pilsen Malt
2 lbs. Munich Malt
1/2 lb. Crystal 80L
1/2 lb. Chocolate 350L

25 IBUs from Tettnanger and Hallertauer

Ferment with the cake from above at 64F.

I plan to mash both at 152F for 90 min. Is that a decent temp for wheat? Higher? Lower?

Thanks in advance for any help!

I have never been a fan of re-pitching onto an entire yeast cake. An ale yeast will typically replicate to 3x the initial number of yeasts, so unless you are going from a small to really huge beer (or 5 to 10 gallons) you are almost always overpitching.

What I would do and have done is brew the hefe, then harvest the yeast in a container (preferably sterile) and then use this calculator to calculate the correct amount of that yeast to re-pitch.

I think mashing at 152 should work just fine, probably do not need to extend it to 90 minutes though. 60 minutes should be more than sufficient.

I would do what berrific suggested, wash the cake and save some/pitch the rest in the WeizenBock. I just brewed a Hefe Saturday and will do exactly this for a Dunkleweizen in a couple of weeks.

Yep, I'm doing the exact same thing the OP is doing. I brewed a 'Rye'zen beer (thanks DB) w/ 3068 last thursday, and I'm going to just scoop a good amount of the yeast at bottling and pitch to a 1/2 batch of Weizenbock.

The moderating team should be proud of me. I was thinking the same thing as the OP and went and found this thread all on my own accord.

So… there’s a small consensus here that the entire yeast cake from a 5-gallon batch is overpitching for a 5-gallon, 1.075 Weizenbock. Would half the yeast cake be more appropriate? More than half? Less?

Also, what is meant by ‘washing’ the cake?

I’ve got two brew days planned on back-to-back Saturdays coming up. This weekend I’m brewing the Hefe. I’m expecting it to have finished initial fermentation by the following Saturday and then transferring it to the secondary right as I finish up brewing the Weizenbock beer. If ‘washing’ the yeast is a process that takes a little time, I’m wondering if I need to do my transfer earlier. (Brew days cannot be shifted. Their destinies have been predetermined.)

Here's the stickied, epic HBT thread Yeast Washing Illustrated that explains yeast washing.

What I do is go to the Wyeast Pitch Rate calculator and enter in the 'starter' info (the starter I made with the White Labs vial or Wyeast Activator smack pack). Then in Step 2 I enter a volume of wort added such that the Total Volume in Fermenter equals the volume in the fermenter for the first brew (this is less than the actual batch volume because the Wyeast calculator ADDS the volume of the starter and I decant the starter liquid). Then in Step 3 I enter a really tiny volume, like .125 gal, and the Final Pitch Rate should show an approximation for how much yeast you have (you can then easily convert that number to yeast cell count if desired).

Example:
Step 1
1 Activator (or vial)
Stirplate: No
.875 gal. Volume of Starter

Step 2
4.625 gal. Volume of Wort Added 1st (this yields a Volume in Fermenter of 5.5 gal. which was the size of the first batch).

Step 3)
.125 gal. Volume of Wort 2nd (this yields a Total Volume in Fermenter of 5.625 gal which is what the volume will be for the second batch).

The result is 52.93 million cells per mL.

You could just use that number or if you want your answer in 'total number of yeast cells' just multiply the cells/mL by the volume in mL.

So:
5.625 gal. = 21,293 mL

52.93 million cells/mL * 21,293 mL = 1127 billion cells (1.127 trillion)

That's a lotta yeast.

I read the first couple pages of that sticky, and it looks like yeast washing is more about collecting than it is 'washing'. Meaning, I'm not understanding why the yeast on the bottom of my previous primary would be any less clean than it would be after all that seperating and settling and packaging. The real advantage seems to be saving on yeast packet costs.

Yeast washing looks like something I'd be interested in doing when the kids are in college and I'm able to brew twice a month. As it stands, I don't have kids (just one), and she's not even in pre-school yet. My time is worth the $8 I'm spending on new yeast packets.

Assuming the previous batch has not been corrupted in any way, what are the downsides of dumping a new wort directly onto the yeast cake?

Judochop said:

My time is worth the $8 I'm spending on new yeast packets.

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Agreed. I've pretty much stopped washing yeasts that I can easily get for $7 at the LHBS, and I get at least two uses out of $7 by top cropping or pitching onto the cake. Top cropping is easy, especially for varieties that produce alot of krausen and I plan on using shortly. That's what I'd do for the original question about weizenbock. This is made easier with a Better Bottle's wide mouth, but can be done with glass carboys too.

Judochop said:

Assuming the previous batch has not been corrupted in any way, what are the downsides of dumping a new wort directly onto the yeast cake?

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If you get characteristic flavors from the yeast (Hefe, Belgian, etc), you might get a much cleaner (less flavor) ferment using the whole yeast cake, and I can attest to that personally.
I pitch onto the whole yeast cake all the time with US-05 and lagers, and I'm quite happy with the results. Fast clean fermentations, and no off flavors.
If you are worried about over-pitching, it's simple enough to swirl up whats left in the fermenter and pour some out.

gxm said:

If you are worried about over-pitching, it's simple enough to swirl up whats left in the fermenter and pour some out.

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Yeah, I plugged in some of my best guesses into Mr. Malty's calculator and it told me I need about 200ml of (relatively dilluted) slurry to get working on a 1.072 OG beer.

So, that's what I'm going with; 200 mils. The rest goes down the storm drain.

gxm said:

If you get characteristic flavors from the yeast (Hefe, Belgian, etc), you might get a much cleaner (less flavor) ferment using the whole yeast cake, and I can attest to that personally.

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Going back to this point for a sec. Are the flavors of the new beer more clean because of the high pitching rate? Like, in layman's terms, "there's so much yeast, they rip through the ferment and don't have time to produce those extra esters and flavors."

So, by using a smaller amount of slurry, I should get those classic hefe yeast flavors?

Or, is it just the fact that I'm using 'used' yeast the reason for the cleaner flavor profile?

Judochop said:

Going back to this point for a sec. Are the flavors of the new beer more clean because of the high pitching rate? Like, in layman's terms, "there's so much yeast, they rip through the ferment and don't have time to produce those extra esters and flavors."

So, by using a smaller amount of slurry, I should get those classic hefe yeast flavors?

Or, is it just the fact that I'm using 'used' yeast the reason for the cleaner flavor profile?

Click to expand...

I'm certainly not an expert, what I've heard is that stressing the yeast can create certain flavor profiles. I've heard that some German breweries intentionally underpitch to create the flavor of their hefes.
On the two occasions that I've overpitched beers where I'd expected distinct yeast flavors (one belgian & one hefe), I didn't get nearly as much flavor as from pitching smaller amounts with future beers with the same yeast. YMMV, etc.