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gatewood

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I decided to brew my own alcohol because I live pretty far away from civilization, but, because of that, my only option has been to try and catch wild yeast (through fruits and wort) and make a starter.

All of my cultures are carbonating pretty well (bubbling quite a bit), and all of them are exhibiting these big, floating chunks (they used to sit at the bottom as sediment, but now they're floating, I assume because of the CO2). Any idea of what that is?
 

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I would imagine that is the wild yeast or bacteria. Eventually, it will probably develop a pellicle - a thin membrane or film, floating at the top - if you let it go that far/long.
 

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Have you thought about just letting wild fruit ferment naturally, with the bacteria/yeast on the skin of fruit or in the air? Some wild ferment ciders can be delicious.
 
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gatewood

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I would imagine that is the wild yeast or bacteria. Eventually, it will probably develop a pellicle - a thin membrane or film, floating at the top - if you let it go that far/long.
hmmm thanks for the insight, I've just made a web search on what a pellicle is:

https://beerandbrewing.com/what-is-a-pellicle/

I guess such bacterial growth is happening due to the fact I'm using PET bottles to brew, of which I was recently made aware that they let oxygen in (damnit!).

Got any other suggestions? The wort I poured into my bottles (yes they have airlocks) did smell and tasted fermented, but do you think I have an actual colony of yeast and lactobacilli? Here I leave some more pictures of another one of my cultures.

********************************************************************************************************
Too far from civilization to get mail?
Labelpeelers will mail a pack of dry yeast for free.
I don't suppose you can mail those things to Mexico?
 

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gatewood

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Have you thought about just letting wild fruit ferment naturally, with the bacteria/yeast on the skin of fruit or in the air? Some wild ferment ciders can be delicious.
what exactly do you mean by that?
 

RPh_Guy

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Wild yeast and bacteria are everywhere. However most wild cultures don't do a great job fermenting wort. A wild mixed culture will typically yield apparent attenuation in the 50-60% range, which is a lot lower than brewers yeast. This means your wild beer probably will be more sweet, and have less alcohol.

The stuff in your photos is characteristic of wild yeast cultures. That is to say, they're unpredictable. It's nothing to be worried about. One of my wild cultures looks pretty much identical to that, with the stuff floating at the top -- however most of mine don't, so my guess is that maybe all your cultures contain similar microbes.
How did you introduce wild microbes?

Yeast can form pellicles, not just bacteria. Since your culture contains wild yeast and bacteria, the appearance of a pellicle would give you no information. Just don't be surprised if a film forms on top.

PET fermenters do not let through an excessive amount of oxygen. They're perfectly fine to use with beer regardless of what yeast culture is used.

The bubbling in your photos clearly indicates that yeast have fermented your wort. You can determine the ABV with a hydrometer, if you measured the s.g. of the wort before introducing your wild culture(s). If there's any way you can get a hydrometer, I'd strongly recommend it.

Lactobacilli? If your beer is sour, then possibly. However there are many genera/species of lactic acid bacteria so there's no way to know if there's Lactobacilli specifically without further analysis in a laboratory.

It's totally fine to use wild yeast to make beer, but you'll need to be careful when you bottle it because over time the level of carbonation may increase.
Also, it will very likely have the flavor of beer that most of us recognize as "Belgian", as opposed to non-phenolic yeast most commonly used to make beer throughout the rest of the world including the Americas.
what exactly do you mean by that?
Unlike wort, wild yeast will fully ferment any kind of fruit juice (or diluted honey or agave) up to a reasonably high amount of alcohol.

Sorry, I'm not really sure which Mexican fruits might make a good wine. If you can extract sweet juice from a fruit, it will possibly make a good wine.

Maybe give these guys a call to see if they could send you a Homebrew quantity of yeast:
https://www.difusa.mx/
Their website doesn't list any of the yeast products unfortunately.

Hope this all makes sense. I'm happy to answer any questions you may have about wild yeast or bacteria.
¡Salud!
 
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gatewood

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Wild yeast and bacteria are everywhere. However most wild cultures don't do a great job fermenting wort. A wild mixed culture will typically yield apparent attenuation in the 50-60% range, which is a lot lower than brewers yeast. This means your wild beer probably will be more sweet, and have less alcohol.

The stuff in your photos is characteristic of wild yeast cultures. That is to say, they're unpredictable. It's nothing to be worried about. One of my wild cultures looks pretty much identical to that, with the stuff floating at the top -- however most of mine don't, so my guess is that maybe all your cultures contain similar microbes.
How did you introduce wild microbes?

Yeast can form pellicles, not just bacteria. Since your culture contains wild yeast and bacteria, the appearance of a pellicle would give you no information. Just don't be surprised if a film forms on top.

PET fermenters do not let through an excessive amount of oxygen. They're perfectly fine to use with beer regardless of what yeast culture is used.

The bubbling in your photos clearly indicates that yeast have fermented your wort. You can determine the ABV with a hydrometer, if you measured the s.g. of the wort before introducing your wild culture(s). If there's any way you can get a hydrometer, I'd strongly recommend it.

Lactobacilli? If your beer is sour, then possibly. However there are many genera/species of lactic acid bacteria so there's no way to know if there's Lactobacilli specifically without further analysis in a laboratory.

It's totally fine to use wild yeast to make beer, but you'll need to be careful when you bottle it because over time the level of carbonation may increase.
Also, it will very likely have the flavor of beer that most of us recognize as "Belgian", as opposed to non-phenolic yeast most commonly used to make beer throughout the rest of the world including the Americas.

Unlike wort, wild yeast will fully ferment any kind of fruit juice (or diluted honey or agave) up to a reasonably high amount of alcohol.

Sorry, I'm not really sure which Mexican fruits might make a good wine. If you can extract sweet juice from a fruit, it will possibly make a good wine.

Maybe give these guys a call to see if they could send you a Homebrew quantity of yeast:
https://www.difusa.mx/
Their website doesn't list any of the yeast products unfortunately.

Hope this all makes sense. I'm happy to answer any questions you may have about wild yeast or bacteria.
¡Salud!
I wanna begin by saying, thanks a lot for the input! :) I was driving blind here (its my very first batch), so no idea if I caught yeast or if I was growing a culture of cholera or something.

Well, you can guess I've got tons of questions (you'll have to forgive my ignorance):

1. What is attenuation? (I think it has to do with the rate of sugar converted into alcohol right?)
2. Why is wild yeast bad at fermenting wort? (the cultures that I left with some fruit pulp bubbled the most)
3. About PET fermenters, what are their pros and cons?
4. What is an ABV?

5. "you'll need to be careful when you bottle it because over time the level of carbonation may increase" why is that different from commercial yeast?

6. "Unlike wort, wild yeast will fully ferment any kind of fruit juice (or diluted honey or agave) up to a reasonably high amount of alcohol." Hmm, so should I mash/blend it first and put it into an airlock and ta-ra?

"How did you introduce wild microbes?"

Just cooked some wort and put it outside for until it was bubbling a bit, which took about 2-3 days. I found that, immediately airlocking the culture after just a day or so, took a lot longer to bubble and develop yeast colonies, better let if breathe for a while so it can reproduce more quickly.
I also used some fruit juice I forgot about, that started fermenting.

"I'm not really sure which Mexican fruits might make a good wine"

We've got pretty much the same fruits as in the US.

"Salud!"

Thanx :)
 

RPh_Guy

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1. "Attenuation" means lowering. In this context, yeast lower the amount of sugar by turning it into alcohol. Most brewers yeast will apparently attenuate around 65-85% of wort, which means the yeast eat that much of the sugar.
2. Wort contains some simple sugars (e.g. glucose), but mainly complex sugars like maltose, maltotriose, and dextrins. Brewers yeast typically ferments everything but the dextrins. Wild yeast usually struggle to ferment the maltose and/or maltotriose, and also typically can't ferment the dextrins.
3. PET pros:
  • Clear
  • Lightweight
  • Somewhat inexpensive
  • Fairly durable
  • Not dangerous
  • Available with spigot and wide mouth
PET cons:
  • Flexible
  • Less durable than stainless steel
  • Can't be heated over 125°F (52°C)
4. ABV = alcohol by volume
5. Commercial yeast is a single strain, and it will reach its maximum attenuation in a short time. Wild cultures will contain a blend of numerous stains and species of yeast. Some stains in the blend may ferment quickly and others more slowly, over a period of months.
6. When making a wine, in most cases you want to first extract the juice. Then just put the juice in a container with an airlock and in a couple weeks you have a dry wine.

If your wild yeast makes a good beer or whatever, you should save some of it for the next batch. Just put some of the sediment in a jar in the fridge. Check on it periodically to make sure it doesn't build up pressure.
We've got pretty much the same fruits as in the US
We commonly use apples to make cider. I don't think apples grow in a tropical climate, but if you can get a bunch of them, then go for it. It's easy to make great cider with wild yeast. You can also use store-bought juice without preservatives, but you will need to introduce yeast.
 
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gatewood

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1. "Attenuation" means lowering. In this context, yeast lower the amount of sugar by turning it into alcohol. Most brewers yeast will apparently attenuate around 65-85% of wort, which means the yeast eat that much of the sugar.
2. Wort contains some simple sugars (e.g. glucose), but mainly complex sugars like maltose, maltotriose, and dextrins. Brewers yeast typically ferments everything but the dextrins. Wild yeast usually struggle to ferment the maltose and/or maltotriose, and also typically can't ferment the dextrins.
3. PET pros:
  • Clear
  • Lightweight
  • Somewhat inexpensive
  • Fairly durable
  • Not dangerous
  • Available with spigot and wide mouth
PET cons:
  • Flexible
  • Less durable than stainless steel
  • Can't be heated over 125°F (52°C)
4. ABV = alcohol by volume
5. Commercial yeast is a single strain, and it will reach its maximum attenuation in a short time. Wild cultures will contain a blend of numerous stains and species of yeast. Some stains in the blend may ferment quickly and others more slowly, over a period of months.
6. When making a wine, in most cases you want to first extract the juice. Then just put the juice in a container with an airlock and in a couple weeks you have a dry wine.

If your wild yeast makes a good beer or whatever, you should save some of it for the next batch. Just put some of the sediment in a jar in the fridge. Check on it periodically to make sure it doesn't build up pressure.

We commonly use apples to make cider. I don't think apples grow in a tropical climate, but if you can get a bunch of them, then go for it. It's easy to make great cider with wild yeast. You can also use store-bought juice without preservatives, but you will need to introduce yeast.
Hello again!

First of all, sorry for the very belated response (they fixed and re-fixed my internet and took ages), I just recently saw your reply... thanks a lot once more for solving all my queries, I'm getting a clearer understanding of how to make and run a fermenter (6 lt. PET bottles work pretty well as vessels, I even had to make my own airlock :p ).

Following on the 2nd and 5th point, 8 of my 10 captured cultures slowly lost vitality and just refused to continue fermenting and died off (or remained utterly stagnant), no matter the amount of sugar (plain glucose) added. The product of my remaining 2 colonies has been slowly improving but its still no where near commercial level, though I'm definitely getting some alcohol to get drunk (I've been distilling some of it), but its not that appetizing. Furthermore, the colonies now keep sinking to the bottom, no matter the bubbling.

I suppose, the next step is to eliminate the remaining bacteria that are spoiling (and maybe poisoning) my wort, by separating pure strains (like saccharomyces).

Got any suggestions on where to begin? I've been applying some of my moonshine on my test cultures, to increase alcohol concentration, but its a very blunt tool, only workable through trial and error, though I've been getting some improvements (I've become quite engaged with the fermentation science, trying to cook some agar as we speak).
 

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RPh_Guy

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Furthermore, the colonies now keep sinking to the bottom, no matter the bubbling.
Sinking to the bottom is normal.
I suppose, the next step is to eliminate the remaining bacteria that are spoiling (and maybe poisoning) my wort, by separating pure strains (like saccharomyces).
Pathogenic bacteria are generally not a problem. A combination of factors (mainly alcohol and low pH) kills pathogens or prevents their growth.

Got any suggestions on where to begin?
If you want a pure culture, isolation on a plate of agar is the way to do it.

If you don't even have access to basic beer yeast I'm surprised you be able to get materials to isolate yeast!

This should help:
https://suigenerisbrewing.blogspot.com/2015/03/new-video-casting-agar-plates.html

http://www.milkthefunk.com/wiki/Wild_Yeast_Isolation
 
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gatewood

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If you don't even have access to basic beer yeast I'm surprised you be able to get materials to isolate yeast!
Making pottery, flintknapping and casting aluminum is pretty easy business, I recommend you give them a try. I could have gone to the store by now for sure, but it has, thus far, become more of a challenge to me, besides, getting a more in-depth understanding of the science, will help me brew and experiment a lot better (I intend on brewing different types of drinks).

oh yeah! I just stumbled across the same dude:


Seems I have some more work to do... but just one more thing, what you've told me so far, is that commercial strains will help me:

1. Speed up fermentation
2. Ferment tougher sugar polymers

Any other advantages/possibilities to it?
 

RPh_Guy

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Commercial yeast generally produces predictable results, and in most cases more clean flavor.

You may (sooner or later) find a wild yeast strain/culture that performs equally well or better than some commercial strains in terms of speed, attenuation, flavor, and even predictability.
 
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gatewood

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Commercial yeast generally produces predictable results, and in most cases more clean flavor.

You may (sooner or later) find a wild yeast strain/culture that performs equally well or better than some commercial strains in terms of speed, attenuation, flavor, and even predictability.
Have you found/isolated any such strains yourself?
 
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RPh_Guy

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Not so far. All of my wild cultures have had relative poor attenuation (as I described above) or were really slow.
Most did smell nice, but I didn't make a batch with any of them.
 
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