Organic apple peel yeast?

[EO74]

Ive heard of people pealing several differant organic apples and putting each one in its own 2 liter soda bottle with a small amount of juice to try and make a natural yeast starter,using witchever one comes out best/fastest.Has annyone else heard/tried this,if so how were your results?The thought of using natural yeasties intriges me!

 

[Edcculus]

I can't say definitively, but my gut says this won't work. For it to really work, you would have to buy directly from an orchard, or pick your own. Organic grocery store apples won't work, because there is so much other wild yeast/bacteria on them from being picked, shipped halfway across the world, stored in a warehouse etc.

Second, contrary to popular belief, apple skins do not have enough of the correct type of yeast to actually ferment anything that will be near tasty. You can end up with some interesting flavors if you press the juice, don't pasteurize or use sulfites and pitch a pure yeast strain. In traditional cider making, the yeast reside in the presses, not the apples or apple skins.

 

[EO74]

Thanks for the info,i think the reason for doing more than one apple type/starter is to insure one variety still has the yeast.I was under the impression the yeast was in the skins?Im going to try it out next time i do a cider and ill post.

 

[chromedome]

Edcculus is wrong.

 

[Edcculus]

Edcculus is wrong.

Sources....??????? If I'm wrong, prove it. I'll gladly concede my point if you show me a source that says otherwise. I know its an internet forum, but its still rude and childish to make a blanket statement like that, when it is apparent that I've spent a lot of time and effort researching.

Here is MY source from Andrew Lea, a former chemist, plant biochemist and food scientist and one of the leading authorities in Cider making. Andrew Lea's Cider making site. I've quoted from the "Harvesting" section under "Fruit and Cultivation".

Before milling, fruit should be washed to remove soil, dead insects, leaves, stones, and rotten apples. It is fortunate that healthy apples float in water (pears don't!), thus providing an easy way to wash and clean the fruit. Clean water should be used to wash each batch of fruit - if the water is recycled, the dirt is recycled too! Don't be afraid of washing away the yeast - you won't! It is a popular fallacy that desirable fermenting yeasts are present on the fruit skin. There are indeed some types of yeast on the skin and in fact there can be up to 45,000 yeast cells per gram of fruit actually inside the apple itself, which get there through the open eye (where the flower petals once were). However, scientific study has shown that these yeasts (species such as Kloeckera and Candida) have only weak fermenting power and they soon die in more than a couple of percent of alcohol. They are not the Saccharomyces yeasts which are required for the successful completion of fermentation.

In a traditional cider-making operation where no yeast is apparently used, the inoculum resides on the press racks, the cloths, the vats, or even on the walls and ceiling. It persists from season to season but virtually none of it comes from the apples. Wild Saccharomyces yeasts are not very common, so this inoculum can take several years to build up but, once established, it can determine the 'house flavour' of a particular product. It is largely a matter of luck whether this flavour is desirable or not. We return to the subject of yeasts in a later section.

 

[BierMuncher]

Edcculus is wrong.

???????????????????

 

[Bluechicken]

I haven't tried this, but I have seen a youtube video that shows a guy doing exactly what you mention.

 

[kunstler]

And again we choose a YouTube video over a chemist/cider expert....seriously? You tube wins over science???

 

[Bluechicken]

Nothing wrong with a youtube video... if a guy shows how he can do something, you can watch it and decide if you agree... or not... there have been plenty of opposing viewpoints here, such as the topic of carbing semi-sweet cider in bottles, which a lot of people said couldn't be done, but others said it could. I gave it a try and it worked nicely. The video was relevant to the initial post, no one said it was better than science. But it might make someone try that technique with a gallon of cider, no harm done if it doesn't work.

 

[FrankyT]

I did this for my first batch of cider just a few weeks ago. I lucked out and it worked perfectly. It may not look like it's doing anything after a day, but soon you'll start to feel pressure. The cider is now carbonating and I'll be drinking by tomorrow.

That youtube video is what inspired me, actually, and I was very curious at the thought of natural yeast, but I was very happy. I am also using the rest for a yeast starter to make bread (I got curious) and shockingly it rose! I'm probably waiting too long to bake it, but it smells deliciously yeasty.

I got my apple from the farmer's market and made sure they didn't wash it, so just ask them! Or pick one yourself. I'd also try and use a few different apples, just in case.

 

[CvilleKevin]

I believe this might work if you use a fresh picked apple from an orchard, although if you are going out to an orchard, you'd be better off IMHO getting a gallon or five of unpasteurized juice. There will be plenty of the same natural yeast in the juice. Then all you have to do is slap an airlock on it and keep it cool. One step and you're done.

OTOH, if you use some random apple from the grocery store, you're more likely get whatever random fromunda yeast lives in the store. Yeast are everywhere. I'm not sure that I buy Lea's explanation because I've done a couple dozen natural yeast ferments with same press and equipment and they have had very different flavor profiles. Some were very good, some not. The best ones were done at low temps (several months at 45-55 F)

OTOOH, you never know, you could discover some new grocery store fromunda yeast that likes to settle on the apples, and which also turns out to decent for making cider. either way, good luck

 

[chainsawbob]

I have tried the technique in the video. I used an organic Gala Apple from Chile. I stripped the skins off and placed it in a bottle with the rest of the macerated apple. I put brown sugar, water, and unsulfured Molasses in it. I shook it every couple of hours to oxygenate it. I got a really good strain from it. Not sure what it is, but it smelled good and has been one of my best performers for cidering. I washed the yeast and now I use it quite often.

 

[chainsawbob]

I think what Edcculus is trying to say is that the molds/yeasts don't originate in or on the apple. They are really a carrier. It acts as a catalyst, or breeding medium. It is a place where most people are able to find them after the fact. It is nature's petri dish.

 

[WVMJ]

Organic doesnt mean not sprayed for funguses with an organic antifungicide like lots of sulfur. Lots of stuff living in the core of an apple after all the flower is exposed to the outside world with bees crawling all over it. Did the guy who picked that organic apple wash his hands No telling where these things come from as the picking bags, collecting bins, sorting tables are used over and over and can be colonized by yeast. The best way to do this I think would be to find an old wild tree and be the one to pick the fruits yourself and crush the whole thing up and dont add anything extra, not even sugar which could stress the wild yeast used to living in a lower sugar environment. Somebody could have squeezed a grape and then fondled your apple before yous showed up and put your dirty hands all over it Anyone really serious about this has to go to a wild tree and not use their regular equipment to process the juice to really select out a wild yeast, otherwise you are just getting whatever is setting around at the farmers market with a lot of other fruit and little kiddie hands touching everything! WVMJ

 

[Mojzis]

For my micro class last year I made this my project. I wanted to see if you can harvest wild yeasts from either organic fruit or non organic fruit. I used copper sulphate as a bacterial inhibitor and left no head space to reduce mold growth.

I used two apples and grapes from South America. One apple was organic, the other and the grapes were not. I skinned each and put them into a nutrient solution out of my yeast book in 15ml vials. Anyway I only got yeast from the organic apple. The grape vials were contaminated by gram neg bacteria, and the non org apple showed a mixture of bacteria and mold if I remember right.

I plated out the organic yeasts and found numerous strains based on colony morphology alone. I then went through and selected the strongest colonies and the ones that produce co2. I was trying to use media testing to identify species but I didn't have enough time. Also spore staining is difficult I found out. I did limit it to a few species though.

I have the write up and microscope pics somewhere.

 

[Warthaug]

Here is MY source from Andrew Lea, a former chemist, plant biochemist and food scientist and one of the leading authorities in Cider making. Andrew Lea's Cider making site. I've quoted from the "Harvesting" section under "Fruit and Cultivation".

I'm afraid that Edcculus is, indeed, wrong. As is his source. FWIW, I'm a working microbiologist/immunologist, and if you follow the link to my blog you'll find many posts on harvesting wild yeasts (including one from cider apples, though-be-it, not Saccharomyces).

In the wild yeasts are typically found growing on plants, where they survive off of the sugars and other materials that are produced by the plants. As you would imagine, this means that yeasts tend to be concentrated on those parts of the plants which are highest in sugars - fruits, nectar, etc. There are a large number of yeast species that you'll find on fruits, including apples, amoung which are our good friends Saccharomyces and Brettanomyces.

If you use fruit as a source of a 'wild' ferment a fairly predictable series of organisms will come to occupy the wort. Again, I have an extensive post about this on my blog, but the coles note version would be:

• Week 1: Enterobacteria & oxidative yeasts (Kloeckera, for example).
• Week 2-4: Saccharomyces becomes more prevalent. The organisms from week 1 will begin to die off as the fermentation conditions become less amenable to their survival
• Weeks 5+: Predominantly Saccharomyces, but Brettanomyes will become ever more prevalent once Saccharomyces has completed the bulk of fermentation.

Throughout the fermentation other yeasts will be present, but in smaller amounts. They can contribute quite a bit of flavour.

Strongly-fermenting yeast do tend to build up in the presses & other equipment used to prepare cider - these are, after all, the ones which thrive best in the environment created when cider is pressed. This is what others were referring to when they mentioned the yeast coming from elsewhere. But that said, the initial source of that yeast is still the materials that pass through the press.

And since people asked for citations (other than my blog, I assume):

• This study assessed yeasts in spontaneously fermented cider musts. Various yeasts were found to dominate musts after two different types of pressing. While the amounts of Saccharomyces varied greatly at first, in both cases Saccharomyces dominated in the end.
• This older paper, using a lower-sensitivity method of detecting yeast, found Saccharomyces living on most of the cider apples they tested. The Saccharomyces were outnumbered by oxidative yeasts, but would be expected to out-grow those yeasts in the relatively anoxic environment of a cider must.

Bryan

 

[chainsawbob]

I tried it again from my neighbor's apple tree, and got the same results. medium flocc, fairly good attenuation. As the sample started to wind down, I hit it again with more fresh cider, and sugar syrup/molasses, etc. It took off again. I repeated this until I got a quart-sized jar of active culture. When this finally went dormant, I cold crashed it in the fridge for a week. I hen washed it out and bottled it in jelly jars. Some, I put glycerine in the culture and put it in the freezer. Some I put in distilled water and left it at room temperature, in a dark place. The rest is in refrigeration and I have been using it rather successfully.

 

[aellis]

how's it taste? sour/funky at all?

 

[chainsawbob]

That's why you streak them in petri dishes. You select the colonies from the dish to purify the strain. Where it comes from, or who touched it doesn't matter in the end if it is a purified strain. By the way, most apples, organic or not are sprayed for "Apple Scab." Without these treatments, apples would be useless to eat. The fungicides that are used are generally non-toxic to humans, but inhibit certain fungal growth, such as scab.

 

[chainsawbob]

Depends how you brew your cider. I put no sugar in the cider before inoculation. I let it ferment fully, then place it in secondary. At this point, it is very tart, and not very sweet. But it does taste very apple'y I then bottle with a cider sugar I make myself. It only takes 2 or 3 days for full carbonation. Then I bottle pasteurize and crash in the fridge. What I get is a really sweet/apple flavor with some tart/after tones, like an apple pie.

 

[chainsawbob]

WVMJ, Get Real Man!!! Do you not pasteurize your ciders at all? The whole universe of fermentation is about germs!!!!!!!!!!!!!!!! you have to be smarter than that. Who gives a damn if their are germs in there from whoever's hands? Do you not understand microbiology? Or do I have to explain that too?

 

[chainsawbob]

WVMJ, You are preaching complete bull****!!!!

 

[MarkKF]

It is my understanding that if the ABV is over 4% bacteria cannot survive.

 

[Warthaug]

It is my understanding that if the ABV is over 4% bacteria cannot survive.

No. Many bacteria survive and thrive in alcohol concentrations much higher than that. The current record holder is Mycobacterium nonchromogenicum which can survive over 75% ethanol. Most common beer-spoilage organisms (lactobacillus, Zymomonas, Pectinatus, etc) easily survive in worts of less than 10% ethanol.

Bryan

 

[WVMJ]

Always a possibility, we dont pasteurize, just drop in some KM to knock out the micros in our ciders. Maybe you can explain jerms to us WVMJ

WVMJ, You are preaching complete bull****!!!!

 

[chainsawbob]

Well, yes you can use these. But is that not a chemical? Are you not adding adjuncts? A lot of people I know don't use these,nor are they very popular in Europe. Personally, they make my joints ache when I drink them in any wine or cider. I believe the original post was about fermenting from wild yeast, trapped from the skins of apples. The answer is "YES". But not only apples. To date, I have wild yeast from apples, pears, strawberries, blueberries..... all acquired by the technique listed in the other post. If you are worried about where and who touched them, then you shouldn't be fermenting. Farming is a dirty business. It's full of germs, bacteria, pathogens, and a whole list of possible nasties. I just resent the previous post, and continual excuses for acquiring yeast stock from the wild in this manner. People have done it this way since before any of us were born. I have no problem with whoever touches my apples before I get them. That just sounds really insulting to people who labor to bring these fruits to market. If you are so paranoid about growing your own trees and such, then you shouldn't be eating anything from a store.

As far as germs are concerned, you need to learn how to purify your wild yeast before you use it. Then its not an issue at all is it?

 

[WVMJ]

So I see why you are having such a problem with my post, so lets see where they wild yeasts come from in pure form. If anyone, a picker, a packer, a supermarket shelf stocker or a customer touches your apples its contaminated with yeast or bacteria that were not on the original fruit. THis is not saying any of these people are dirty or unwashed, just that if you touch something you transfer some bugs from your skin to the fruit. If you want TRUE SOURCE wild yeasts from an apple, you almost have to go out and pick it yourself, otherwise you have no idea where the yeast came from. If there are some grapes in store and people fondle the grapes and then walk over to your apples and fondle them and put them back and you come along wanting to harvest wild apple yeast then really you are possible getting grape yeast. You can harvest "wild" yeast off of almost anything, but do you want random wild yeast or apple specific yeasts? I have many wild apple trees on our farm, unsprayed with anything, if anyone wants to harvest some true wild apple yeasts you are more then welcomed to pick some and give it a try with a true source. Yes KM is an additive, but yeast also produce it, its a chemical but so is water, apple juice is just a mix of chemicals. Go all natural if that makes a good cider for you great, just dont think that you are getting a real apple specific yeast in a supermarket environment with so many sources of contamination from other fruits and people touching everything. WVMJ

 

[Mojzis]

I don't want to get into the argument but I thought I'd add my thoughts on the yeast contamination issue.

Yes everyone is a walking petri dish of microorganisms. There are undoubtedly numerous species of microorganisms on the grapes, apples, etc. When someone touches the apples that does not mean they are now contaminated with foreign yeasts. We aren't talking about sterile nutrient rich substrate untouched by other microorganisms. There is going to be an established community much like on our skin or in our digestive tract. These communities don't just allow foreign organisms to take hold. The same reason why we don't get sick everyday from eating who knows which pathogenic microorganisms in our food.

My point is the belief that once a fruit is touched it is contaminated by foreign yeasts is likely not true. Not to say it isn't possible, but just unlikely. Also who cares anyway? Yeast is yeast no matter where it came from (mostly, but lets not go there).

 

[WVMJ]

That is probably very true when the apple is on the tree, its even the goal of Hollistic apple growers. But in the store their enviornment has changed, they have been handled and in contact with each other. The old one rotten apple spoils the whole bushel is very true. My take from the OP was wanting to find a wild yeast just from the apples, an apple specific yeast, looking for it in a store is not the optimum place to find it, going to an orchard is better, finding an old wild apple tree that hasnt been sprayed by anyone, organic or not, would be the most likely to produce an apple specific yeast. And no, yeasts are not just yeasts. WVMJ

 

[MarkKF]

I read the best way to harvest wild yeasts is to pick a few yourself, chop them up and make a starter. If you get a viable yeast and desirable profile then you pitch the starter into your next batch.

 

[Mojzis]

I think thats where the confusion lies: the idea of an apple specific yeast. Yeast by nature are not specific.

Yeast inhabiting your wild apples isn't necessarily going to produce the profile you are looking for. Your chances of finding this profile is just as good by collecting yeast from your beard, from the leaf of a tree, etc. I'm with you on the sprayed vs not sprayed debate. The same yeast that ferments sugars on the sap of a tree will ferment your bread, your cider or your beer. If it will make a pleasing profile to you is a matter of attempts and hoping you find a pleasing strain/community, not necessarily the surface on which it was found.

 

[BeerLoverHere]

I read the best way to harvest wild yeasts is to pick a few yourself, chop them up and make a starter. If you get a viable yeast and desirable profile then you pitch the starter into your next batch.

Yep, this is what I did when harvesting persimmons from a tree this past fall: Picked the persimmons, placed in clean/sanitized container, chopped up most all the skin from the persimmons on a sanitized cutting board, placed in a growler, made a starter, and added some hops to ward off any bacteria. Worked well

 

[WVMJ]

Of course there are specific yeasts for specific fruits just like there are specific forms of powdery mildew for different fruits, the yeasts adapt to better take advantage of the fruit they evolved with. That is not to say a grape yeast wouldnt work well in an apple ferment, they do, but apple yeasts might not have evolved to ferment the higher levels of sugar in grapes so they might not work well in a grape must. Just like yeast that evolved on wheat also might not be able to fully ferment a grape must since they have never seen such high levels of sugars just as examples. Who knows if anyone has actually searched professionally for an apple cider specific yeast, some are sold as cider yeast but they never seems to be a story about where they came from. WVMJ

I think thats where the confusion lies: the idea of an apple specific yeast. Yeast by nature are not specific.

Yeast inhabiting your wild apples isn't necessarily going to produce the profile you are looking for. Your chances of finding this profile is just as good by collecting yeast from your beard, from the leaf of a tree, etc. I'm with you on the sprayed vs not sprayed debate. The same yeast that ferments sugars on the sap of a tree will ferment your bread, your cider or your beer. If it will make a pleasing profile to you is a matter of attempts and hoping you find a pleasing strain/community, not necessarily the surface on which it was found.

 

[Warthaug]

Of course there are specific yeasts for specific fruits just like there are specific forms of powdery mildew for different fruits, the yeasts adapt to better take advantage of the fruit they evolved with.

If you have evidence of this I'd love to see it, because your claims fly in the face of pretty much all work done analysing Saccharomyces natural niche. There has been a fair amount of work done on wild Saccharomyces yeasts living on sources such as apples (see some of my earlier posts in this thread for some example links) and none of them were able to identify fruit-specific yeasts. In fact, Saccharomyces on fruit are relatively rare (even on grapes and berries) - for example, Saccharomyces is found colonizing less than one percent of apples in an orchard. The primary environmental niche for Saccharomyces appears to be the bark of trees - especially oaks.

The mechanisms by which these yeast then spread to fruit is also fairly well understood - namely, insects such as wasps which feed on sugars from treebark and fruit.

There is one exception to this - vineyards - where humanities >10,000 years of cultivating grapes has led to selection of grape-specific yeasts which appear to survive via spread between grapes, soil & farming equipment.

Who knows if anyone has actually searched professionally for an apple cider specific yeast, some are sold as cider yeast but they never seems to be a story about where they came from. WVMJ

I know - as would anyone who read the earlier posts in this thread. This is an area of intensive investigation, and we're quite aware of where these yeasts came from, as indicated in the various links I, and others, posted at the beginning of this thread.

Bryan

 

[WVMJ]

Interesting, that would fly against the way nature usually works, might be they need to look where apples originated to find the wild source. WVMJ

 

[siletzspey]

The primary environmental niche for Saccharomyces appears to be the bark of trees...

Any speculation on the merits (and hazzards) of using say oak bark to seed yeasts into a batch of pasteurized cider? Could it be a more consistent and/or concentrated source of yeasts?

Its also interesting to consider that old farm houses and press equipment become fine environmental homes for the yeasts.

--SiletzSpey

 

[MarkKF]

Its also interesting to consider that old farm houses and press equipment become fine environmental homes for the yeasts.



--SiletzSpey

I've read that the old Belgian breweries used open fermenters with vents in the barn to let in wild yeast. They did this for centuries.

But modern science has found that while it may have worked early on later the yeast actually lives in the barn itself.

 

[Warthaug]

Any speculation on the merits (and hazzards) of using say oak bark to seed yeasts into a batch of pasteurized cider? Could it be a more consistent and/or concentrated source of yeasts?

Its also interesting to consider that old farm houses and press equipment become fine environmental homes for the yeasts.

--SiletzSpey

I've isolated a number of wild yeast strains from a number of sources, including various tree barks including maple & oak bark. So long as you follow good practices (e.g. not drinking/tasting until at least a month of fermentation has passed, using 10-15 IBU wort @ ~1.040 for yeast collection, etc) you should be safe - that's no guarantee that the yeasts you isolate will be worth using, but they won't kill you.

Its a shameless self-plug, but on my blog I have a bunch of articles (and videos) on capturing, testing and using wild yeasts.

As for presses/etc harbouring yeast, it makes perfect sense - you're starting off with an ideal home for the yeasts (wood) and ten providing repeated dosings of sugar-laden food for them to eat.

Bryan