When to add second yeast?

[Pappa_Bjorn]

My first post here! Please forgive any errors!

I sort of emergency ad lib'd an elderflower mead batch since the elderberry trees were hours away from being done blooming. Afterwards I calculated the total potential ferment ABV to ~10% (OG1.070), but I pitched with Safale US-05 ale yeast (~8%ABV upper limit) since that's all I had on hand.

I'm fermenting in 2x5L primaries (abt 1.1 gallons of must in each) and realized I could do a bit of science by splitting the batch; one jug I could leave with Safale US-05 to get a sweet dessert mead, and to the other I could add a cheap dry wine yeast, and maybe even some tannin when bottling to get an extra dry and astringent mead.

My main question is:
When should I add the wine yeast? I'm thinking if I add it now, two days in, it would probably get out-eaten by the already bubbling ale yeast? But on the other hand, could it really thrive enough, fast enough, if I add it after the ale yeast dies at ~8%? And how long might that take? Also I'm sorry if I'm way off on everything here. This is my first mead after a few ales, and I haven't really researched much at all.

Anyway here's the recipe I made up, for 10L/2.5 gal must:
Steep@~72C/160F no flame, 1h:
Elder flowers, destemmed 800ml
Rose petals 400ml
1/4th bitter orange peel, whole
1 tea bag russian earl gray (quickly removed, just for complexity/tannin)
1 tea bag prince of wales (-"-)
2g crystal 2,8%AAU@60C/140F (yes...)
Blackcurrant leaves 100ml@50C/120F (very volatile scent, so low temp is compromising pasteurizing and flavour)

Then mixed with pasteurized fermentables:
700g wildflower honey
700g orange blossom honey
320g acacia honey
1L bitter-ish golden grape juice not from concentrate@14brix

Pitched w. Safale US-05 ale yeast (so far). Fed with fermaid according to this formula. Intend to 'dry hop' ~400ml de-stemmed elderflowers, 200ml rose petals, and some lemon zest in secondary. Not sure if I should add citric acid, lactic acid and/or tannin to any bottle.
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Thanks in advance!

 

[RPh_Guy]

Hey and welcome!

I'm not a mead expert. I've tried a mead recipe with a whole bunch of added stuff like this and it's not something I'd repeat.

My suggestion for the dry batch is to rehydrate and pitch a packet of Red Star Premier Cuvee, as soon as you can get some, or alternately EC-1118. Both are well behaved with high ABV tolerance.

 

[Maylar]

I can't comment on your recipe other than it looks complicated to me, but as for yeast I would wait until the ale yeast quits before adding any more. If you use nutrients you'll likely find that S-O5 will go well beyond 8%.

 

[Pappa_Bjorn]

Hey and welcome! ...

I can't comment on ...

I'm adding nutrients. I wouldn't mind the S-05 giving up a bit early for sweetness, so maybe I'll skip the 1/3rd mark nutrient add for the 'sweet' jug. Thanks for the tip!

Regarding the recipe, it's really a 3gal w/ 1L elderflower, .5L rose petals, .25L blackcurrant leaf, and bitter orange zest, fermented on a 50-50 of low flavour/orange blossom honey w/ 1L grapefruit juice for extra bitter and yeast nutrients. The goofing off with the tea & hops didn't affect the must flavour profile much.

Still not sure whether to add the wine yeast immediately or at S-05 death though...

 

[RPh_Guy]

Still not sure whether to add the wine yeast immediately or at S-05 death though...

My reasoning was just that adding wine yeast earlier would allow it to finish faster/cleaner since it has more opportunity to grow if there is more sugar & nutrients available. That said, I don't think different timing would really make much difference.

Quick math shows your additives might drop the effective OG to around 1.060 and I wouldn't be surprised if US-05 finishes dry.

Cheers

 

[loveofrose]

US-05 will go to 13% ABV in mead. Your mead will easily go bone dry without wine yeast. See here under experiments and Ale yeast experiments for more mead centric info: https://denardbrewing.com

 

[Pappa_Bjorn]

Quick math shows your additives might drop the effective OG to around 1.060 and I wouldn't be surprised if US-05 finishes dry.

Got a too high measured OG vs. recipe, and thus adjusted the recipe down a bit for assumed losses. My measured is 1.070, aka 9.7%. I guess you're right about the additives ruining the ferment potential a bit.

US-05 will go to 13% ABV in mead. Your mead will easily go bone dry without wine yeast.

Interesting indeed...

Well, I have made up my mind then! I'll immediately add a rehydrated pitched wine yeast ('cause why not), keep giving that jug a little bit extra nutrients, 'dry hop' it all with some elderflower and lemon zest, and possibly bottle with citric acid, lactic acid and/or tannin, depending on how the fresh mead tastes upon bottling.

Thanks for the input y'all! I'll return with the results and comparison between adding wine yeast vs. not.

 

[AZCoolerBrewer]

Hops have a antiseptic quality that allow dry hopping with no risk. Other things may not be as risk free. Be sure to figure a way to sanitize post fermentation additions to avoid unexpected outcomes. I have personal experience with US-05 fermenting beyond 8%.

 

[Maylar]

"Why not" is because some yeasts don't play well together. Ale yeasts are sensitive to the competitive 'kill' factor, and some wine yeasts possess that factor. I dunno what happens if you pitch a killer yeast into an active ferment. The advice you've been given is to let the S-05 finish and see what you get.

 

[RPh_Guy]

"Why not" is because some yeasts don't play well together. Ale yeasts are sensitive to the competitive 'kill' factor, and some wine yeasts possess that factor. I dunno what happens if you pitch a killer yeast into an active ferment. The advice you've been given is to let the S-05 finish and see what you get.

The US-05 has to stop somehow, whether it's kill factor, chemical stabilizers, alcohol poisoning, or running out of sugar.

 

[Pappa_Bjorn]

...Be sure to figure a way to sanitize post fermentation additions to avoid unexpected outcomes. I have personal experience with US-05 fermenting beyond 8%.

Haven't 'dry hopped' any additional elderflower/rose petals/lemon zest yet, but it's all in the freezer atm. I'll 'pickle' in a minimal amt of 96%/190° and let it melt (sealed 'cause volatility) to room temp for a few hours before adding in boiled hop bags. If there's still a living organism to infect my batch in there after that, it has earned it's right to do so.

"Why not" is because some yeasts don't play well together. Ale yeasts are sensitive to the competitive 'kill' factor, and some wine yeasts possess that factor.

I'm concerned there'll be a lot of autolysis/bad fermentation since the two strains aren't selected to be friends. I did split the batch and only pitched S. Bayanus in half and kept S-05 solo in the other, so it'll be an interesting piece of science.

The US-05 has to stop somehow.

Aye. An unpredictable death too since my calculated final ABV will be ~10% so I can't really tell if it will die from starvation or alcohol poisoning. Two dry meads @10% with the same ingredients but different yeasts, or one sweet and one dry. Time will tell.


Anyway general update for future readers and future me:
+18d since first S-05 pitch. +15d since S. Bayanus pitched in half. +8d since final nutrient feed (+1d, 2d, 3d, 7d). Aerated +3d. No pH adjust. ~-1d to 'dry hop' w/ frozen elderflower, rose petals & lemon zest, sterilized gingerly in 96%/190°. ~-10d? until bottling w. sugar, (oak-)tannin, and possibly lactic acid. Neighbours moved whole batch from cold (18°C/64°F) to room temp (22°C/72°F) ferment at ~+7d. Not sure how it'll affect flavour but the ferment rate increased a LOT. Neighbours made me mix up which half is which but I'm assuming S. Bayanus is currently cloudier, bubbling way more, and has a white mineral-ish sediment vs. pure S-05 which looks like a clean brewed weiss with only slight activity and sediment.

Tasted amazing at +7d. The strong elderflower taste in must reduced to virtually nothing though (like the elder ales I've tasted; no discernible elder!). I guess elder is too volatile to ferment. Will be interesting after dry hop add though. That might survive into the bottles. Tasted A LOT like rose petals in a very pleasant way (more than the must did!). At +18d both airlocks smell a lot like rose petals, and quite yeasty. A little bit sour, but no discernible off scent (yet).

I'm thinking my next and second mead will be following Bray's method (cause holy f*** does mead ferment slow!) and go fully rose petal, blood orange/blood grape instead of golden, more (added) tannin, more tea leaf, more flavour intense honey, dry hopped oak chips, and still some blackcurrant leaf. I'm hoping it'll be red, dry, fresh, astringent, icy cold, and not too slow to ferment.