Does anyone use wild yeasts to make mead?

Wine Making Talk

Help Support Wine Making Talk:

BernardSmith

Senior Member
Joined
Dec 27, 2011
Messages
3,481
Reaction score
1,714
Location
Saratoga Springs
I am interested in experimenting with wild yeasts to ferment my honey meads over the next 12 months. Trying to capture and then propagate yeasts from , for example, plums, from raw honey, from inchet and kitel (gesho), from figs and so forth. *** Just begun to capture these yeasts (since Sunday) and so the colonies I have in mason jars are far too small at the moment to know if they are even viable (though I used a scant pound of raw Brazilian wild flower in a gallon of water for this honey experiment and when I agitate the carboy that this is in I do get a very large amount of gas) . Anyway, is there anyone else on this forum interested in experimenting with wild yeasts rather than lab cultured varieties? Methinks that IF (and that is a very big if ) I can find a viable and tasteful fermenting culture that this might result in quite uniquely flavored meads.

*** There seems to be at least two ways that folk cultivate wild yeasts - one is to work with colonies of yeast as I am. Another more "scientistic" approach (not more scientific IMO, but an approach that has the appearance of being more scientific) is to use petri dishes to isolate and select cultures that you grow on agar and so ensure that you are dealing only with yeast and not a mix of yeast and other bacteria and fungi or mold. This second approach means that you might be able to cultivate very specific strains of yeast the equivalent of 71B or D47 and the like, whereas capturing yeast on the skins of fruit may mean that the colony is made up of a very diverse community of yeast whose make-up may change in light of the amount of sugar and or alcohol and or acidity etc that they are exposed to...
 

MDH

Junior
Joined
May 19, 2014
Messages
25
Reaction score
5
Isolating yeast isn't the same as using wild fermentation.

With wild fermentation, you are carefully monitoring must conditions to maintain a relatively low pH (ideally, less than 4.0, though most grapes are already beneath this level), a balanced gravity (not too low, or too high) and anaerobic conditions at all times during the ferment.

The idea and principle of such a fermentation is that there are thousands of different yeasts and bacteria alive within the ferment, but those the most adapt to the conditions they are subjected to will overtake and complete the ferment successfully.

Isolating a single strain and fermenting with it counteracts this: If the strain you have isolated isn't well adapted to the medium you are fermenting, you will eventually have to supplement nutrients or conditions that it needs to actually thrive.

One thing you can do is crush some fresh, unwashed fruit and put it into a ziplock bag with a bit of water. If the fruit is not acidic, add acid before doing this. Then, carefully push all the air above the fill-line in the bag out and seal it. There will be enough dissolved oxygen within the bag to allow yeast to grow sufficiently, and a strong fermentation should begin within several days.
 
Last edited:

BernardSmith

Senior Member
Joined
Dec 27, 2011
Messages
3,481
Reaction score
1,714
Location
Saratoga Springs
Thank MDH, I am not trying to isolate a single strain. That does not interest me very much. I am focused on growing colonies that I find on fruit and the like. What I am isolating is the fruit itself (so I have some cultures from plums in one mason jar and some cultures from figs in a separate jar. Not sure the advantage of using a ziplock vs mason jar.
But on a more scientific level I am not sure why I want to inhibit all oxygen. I am trying to propagate the yeast not at this time make a mead. Don't daughter cells need O2? I realize that this O2 will also encourage other non yeast bacteria but won't the level of alcohol the yeast produce inhibit the growth of those bacteria? And again, at this point I am not interested in fermenting anything. I am trying to grow the population of wild yeast - so it's not very clear why I want to crush the fruit. My thinking at this point is simply to create a sugar solution whose gravity is pretty close to the gravities I aim for when I am fermenting mead (I like session meads about 6 % ABV)
 

MDH

Junior
Joined
May 19, 2014
Messages
25
Reaction score
5
You aren't inhibiting all oxygen. As I mentioned, there is enough dissolved or fine bubbles of oxygen within the crushed fruit to allow sufficient growth. For the actual ferment of mead itself, the carboy's headspace should also provide enough oxygen for the first several days after you pitch the living jar or bag into it.

Having a limited supply of oxygen during the actual ferment is essential because of course, you want lots of yeast and bacteria to produce alcohol, and some of the acids that esterify as it ages - but on the other hand some of the other microbes in a wild ferment will use air, sugars/ethanol and nutrients from autolyzing yeast/bacteria to produce very strange smelling and tasting compounds you definitely don't want - and to answer your question, no, ethanol does not inhibit all of them.

So, it is better to have yeast performing the ferment at a slightly slower pace, than to have oxygen available during all times during the ferment in order to build a high number of cells, and end up providing a space in which some non-saccharomyces strains and bacteria will form a pellicle and do things you don't like. It's also of course delicate balancing act, as if you don't have enough oxygen at the beginning, you have a new set of risks, such as a bacteria that can create new cells by substituting oxygen with something else (or derive it from a sugar) and will outperform the yeast.

Regarding the ziplock: A ziplock is merely a simpler version of, say a mason jar (like you are using) with an installed airlock. It will allow gas to build in such a way that it signals an alive ferment, without allowing air in. A ziplock can be disadvantageous when you forget to allow the gas out (for pretty obvious reasons).
 
Last edited:

BernardSmith

Senior Member
Joined
Dec 27, 2011
Messages
3,481
Reaction score
1,714
Location
Saratoga Springs
But you are stages ahead of me. I am simply trying to propagate the colony of yeast on the fruit. At this stage I am totally - 100 percent disinterested in fermenting anything. I am simply allowing the yeast to eat sugars and provide them with nutrients in order for the colony to bud and grow. The "actual fermentation" will begin once I have enough suitable and viable yeast and after I have decanted any and all liquor above the yeast and after I have washed the yeast and that I assume will take several feedings and decantings...
 

MDH

Junior
Joined
May 19, 2014
Messages
25
Reaction score
5
The problem with your approach, is that a wild culture occurs in stages: First you start with non-saccharomyces yeast and higher pH bacterial strains. Then finally, saccharomyces strains take over. When they run out of simple sugars to consume or can no longer tolerate the alcohol content, other strains such as brettanomyces or mutations of saccharomyces take over.

What this means is that if you wait until you have a wild culture that has fully performed and finished a ferment, and then pitch it into a new ferment, you may unintentionally end up fermenting something largely, or almost entirely with the "last microbe standing", the last one to dominate your ferment in large numbers, which could not be what you want.

I would recommend you crush some fruit in a 18-20 brix medium of honey and water, at a pH below 4 and in a warm room. When a fermentation is very active, add it to the carboy of mead at similar specs - pH <4, reasonable S.G., etc and allow it to ferment out at a decently warm temperature. When your S.G. runs very low, chill and rack the mead (if your wild strain is low flocc definitely use a clarifying agent), and sulfite it sufficiently to prevent secondary before bottling.
 
Last edited:

BernardSmith

Senior Member
Joined
Dec 27, 2011
Messages
3,481
Reaction score
1,714
Location
Saratoga Springs
My approach - and where I am in the process is very similar to the following:
http://mutedog.beer/blog/harvesting-yeast-from-honey
[FONT=&quot]http://mutedog.beer/blog/how-to-harvest-wild-yeast

The key difference is the next step as most folk who work with wild yeast seem to be brewers and not mead or wine makers. Since I routinely make one gallon batches (I like the freedom that single batches afford me since I can treat every batch as an experiment or a learning experience) making a less than enjoyable single gallon of a mead is not a terrible loss...
[/FONT]
 

BernardSmith

Senior Member
Joined
Dec 27, 2011
Messages
3,481
Reaction score
1,714
Location
Saratoga Springs
Just checked the gravity of the batch of Brazilian honey must with my refractometer. On 7/23 the must had a gravity of 1.032; 7/31 the gravity had dropped to 1.025 and this afternoon (8/7) the gravity was at 1.019 so it is certainly slower than lab cultured colonies but there seems to be enough yeast (and other beasties) to drop the gravity 13 points in 14 days.
 

MDH

Junior
Joined
May 19, 2014
Messages
25
Reaction score
5
Hi Bernard,

How has this worked for you so far?
 

BernardSmith

Senior Member
Joined
Dec 27, 2011
Messages
3,481
Reaction score
1,714
Location
Saratoga Springs
Good question. Have been away on vacation almost a week but before I left I measured the gravity of a near pound of honey I had dissolved in a gallon of water (starting gravity was 1.030) and it had dropped to about 1.015 with only the yeast that was in that honey. Hadn't tasted this yet but the smell was good and there was about 1 or 2 mm of sediment at the bottom of the carboy. My aim is to collect this sediment - I assume that almost all of it is yeast - and use it to ferment another batch of honey and if that works and provides me a pleasant batch of mead to use the yeast from this second batch to see how it will ferment a third batch.
At the same time I have growing a similar colony of yeast that I collected from some marjoram flowers and this seems also to have resulted in what looks like a usable colony of yeast - again the smell is very pleasant but I have yet to taste the "wine" it has made from the must it is growing in. If this tastes OK I will wash that yeast and see how it deals with another small amount (1 lb ) of honey...
 

BernardSmith

Senior Member
Joined
Dec 27, 2011
Messages
3,481
Reaction score
1,714
Location
Saratoga Springs
I am familiar with Zimmerman but his approach (he says) takes about a year before his meads are drinkable. These days, you can make very drinkable meads (albeit low alcohol - session meads, if you like) in a month or two. It should (can) take about a week to ferment the sugars dry ... and another three or four weeks - perhaps a month and a half before the mead is very delicious. - Check out Groennfell Meadery. They don't use wild yeast but they do publish their recipes and protocols. :b
 

Keith1940

Junior
Joined
Aug 29, 2017
Messages
25
Reaction score
12
In my link he does say to wait 9-12 months before bottling so the bottles don't explode when capped. I checked out GM, some good recipes and they look very simple. The time to drink them is much quicker with the GM methods vs the viking way. Now I know what GM means around here!
 

BernardSmith

Senior Member
Joined
Dec 27, 2011
Messages
3,481
Reaction score
1,714
Location
Saratoga Springs
If Zimmerman is afraid of exploding bottles that suggests to me that he bottles before all sugars have been fermented out and /or he assumes that simply because the gravity has not fallen for a few days or weeks - or even months , the yeast has given up the ghost. Not necessarily true and so if there is any residual sugar it is possible that without stabilization (or filtering) the yeast can suddenly become active again and the gas build up is enough to either pop corks or burst bottles (if you use crown caps and beer bottles).

For the record, the Brazilian honey I fermented using yeasts that were in the honey seems to have fermented bone dry. I started with an SG of about 1.030 and using my refractometer it looks as though I am below 1.010 which when converted using Morewine's refractometer calculator indicates that the mead is now below at .998.

My next step is to rack the mead off the flocculated yeast and add a new batch of honey to the lees (the yeast) and see what happens to this batch and how well (or not) it tastes. But this time the starting gravity of the must will be about 1.050.
 
Last edited:

MDH

Junior
Joined
May 19, 2014
Messages
25
Reaction score
5
Do keep us updated Bernard, and perhaps try cold stabilizing the racked mead and using a clarifying agent. Cheers
 

Latest posts

Top