using both commercial and wild yeast

[GeneDaniels1963]

I am going to do a Raspberry ale, similar to what I did a few months ago. This time I am thinking about a mixed fermentation using the wild yeast from the raspberries and Nottingham. Should I use the wild first, then clean it up with the Nottingham?

 

[RPh_Guy]

Wild yeast is very unpredictable in beer.
I'd highly suggest adding some Brettanomyces. Give it 6-24 months to finish.

Nottingham alone might not be much help if the wild yeast/bacteria produce any amount of off-flavors or kill factor. On the other hand Brett is wonderful at cleaning up those off-flavors and will attenuate regardless of kill factor.

It's advised to add fruit within weeks of bottling though.

Cheers

 

[mashpaddled]

You probably won't have enough wild yeast and bacteria on the raspberries that can ferment malt sugars to do a good job creating a hostile environment for less desirable organisms. If you don't have a good early fermentation you are more likely to end up with foul or even unsafe metabolism by illness-causing bacteria or mold.

I'm not entirely sure what you intend to create here but dropping in the raspberries and then later Nottingham is probably not the best path.

 

[RPh_Guy]

Mold growth is prevented by standard methods of keeping out oxygen -- an airlock.

Adding Brett like I suggested will guarantee enough alcohol to kill any pathogenic bacteria.

 

[GeneDaniels1963]

I'm not entirely sure what you intend to create here but dropping in the raspberries and then later Nottingham is probably not the best path.

What I am trying to do is see what my wild yeast will do in a beer. The same yeast have made some marvelous wines. I am thinking that in a wort it might give me some funk, but
know beer wort is a very different medium. That is why I have been asking for criteque.

I am leaning toward starting with Notthingham, then adding the raspberry yeast starter in the secondary, at the same time I add the raspberries themselves. I am thinking the wort will already have enough alcohol by then to protect it from anything too bad.

 

[RPh_Guy]

The starter is a good idea and will reduce concerns for pathogens or mold.

So far I've made made 7 wort starters with wild yeast (pre-acidified and hopped @ 2g/L). 6 of those didn't attenuate very well after 2 months, only about 50-60% apparent attenuation. Unfortunately I opened them too frequently and most of them grew mold. 2 of them were foul enough to be dumped. 2 presumably have hop-tolerant lactic acid bacteria because the pH dropped.
The other 5 are currently in phase 2 testing, with no mold so far since I've been more careful. Most or all of them have nice fruity aroma. No Brett unfortunately.

 

[GeneDaniels1963]

I did a starter from muscadines a few years ago. It was wonderful! Made a really nice white wine. But this will be a first with beer, and since wort is so much harder to ferment I thought I should back up with Nottingham.

 

[RPh_Guy]

Go for it! You can add Brett later if it doesn't work out to your taste.

 

[GeneDaniels1963]

update

The starter from raspberries and sugar water rocked along for 10 days or so before fermentation completely quit. It smells really nice, very strong raspberry, but I don't know what ABV as I did not check SG at the start.

Anyway, I just poured it into 1 gal of wort made from dark DME and some date syrup, SG 1.075. I added some yeast nutrient. I will watch what it does, if it quits too soon, I will add Nottingham to finish up. But I really want to see what my wild yeast can do. And besides, its only 1 gal, the worst can happen is I have to hold my nose while I drink it

 

[RPh_Guy]

FYI
When making a yeast starter for beer, it's way better to use wort rather than simple sugar. The yeast get very lazy about fermenting wort sugars ... and the yeast in this case already have an uphill battle.

Good luck!

 

[GeneDaniels1963]

I'll let you know how it turns out