March 3, 2019 - 8:48am
Wild yeast on fruits and vegetables
In The Sullivan Street Bakery, Jim Lahey describes harvesting wild yeast from the waxy coating on some fruits and vegetables. The pictures showed a dark-leaved kale with a whitish coating.
But where did the yeast on the leaves come from?
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It's everywhere, just floating around.
More from soil and water than from air. Yeast doesn't have wings. ☺️
It's not particularly useful to "harvest" yeast from vegetables & fruits, and it may actually set back your progress - in the same way that you don't "harvest" the chess club to get new football players. ? Where do you find football players? Look for the football. Where do you find yeast for baking? In flour and on grain. Forget the so-called harvesting. Lahey is either doing something that he finds entertaining and educational, or else he's wrong - but one thing he's definitely not doing with that method is improving his baking.
Yeast is certainly in the soil and water, but it moves via air currents. Consider how airborne yeast is collected in making Lambic beer. The brewers simply expose the unfermented beer to the atmosphere in ventilated sheds and let it supply the yeast. And as you know, beer is just liquid bread and vice versa.
That is indeed what the brewers claim is happening. It sounds like a good guess. I don't believe they've tested their guess, though, by actually trying to prove it wrong - which is the only sane way to test that kind of guess.
Microorganisms travel in tiny amounts through the air. But most of that is insignificant as they don't tend to survive on the random environments where they land and they compete with all the other microorganisms travelling the same way.
What happens in plants (yeasts on rye flour, yeasts on cherry or apple blossoms, yeasts on fruits, etc) is that the yeast is symbiotic or parasitic (not sure which classification) with the plant during its entire life cycle, and is passed to the next plant on the surface of the seed.
Us humans have plenty of bacteria on our skin that is always associated with humans (we are never without it), such as the Limburger cheese bacteria that inhabits our belly buttons. It's the same kind of way with fruits.
Yeasts in sourdough come from the seeds/berries via the flour, and not from the air in your house as many have apocryphally claimed. It's been proven by making a starter in a sealed sterile environment.
Mike, during the winter months when mant fruits and vegatables are not readily avilable in the yard, what would be a good source os yeast for a yeast water. Either to start a new one or maintain an existing YW?
Danny
This whole idea of using yeasts different from the ones naturally present in the flour is new to me. So I have no idea. My guess is that the only way to maintain such a strain of yeast is to continually feed it its natural food source where you got it originally. Is that how it works?
I remember reading that the yeast used for certain whiskey was originally harvested in spring from blossoms in bloom, but then maintained commercially like any other commercial yeast. Can't find that via google right now, but that's how I remember it.
I would expect concentrations of yeast during the winter would be very low.
In all honesty, I really don't know what I'm talking about. So I'd better stop talking before I lead someone to believe a falsehood.
I have no long term experience with yeast water. But in reading your reply, I may have learned something.
I have had a YW in the frig for probably 6 months with no attention. It still bubbles, but I thought that it needed more blossoms, fruit, etc to bring it back to max health. But maybe the yeast are alive and well and all that is needed to strengthen it is a little unprocessed sugar for feed.
Can anyone help with this?
to your query Dan but there are so many observations above that I won't try to address them. I started my apple yeast water over 6 years ago. All it took was one week and a NON-ORGANIC apple in some water from the faucet. I cut up the apple and added it to enough water in a quart jar to keep it floating. I then put it in my Miele oven with the light on. I took it out a couple times a day and stirred it and recovered it loosely with the metal lid on the quart canning jar. It was bubbling after a couple days and smelled like cider.
I added 50 g of it to 50 g of white flour and it bubbled up. I have been making bread with it ever since.
If you see folks adding sugar or honey it isn't necessary....the fruit is enough sugar..MORE than enough. If you see folks keeping it in a tightly closed container ...THEY ARE WRONG ! It isn't an anaerobic process...you DON'T want alcohol ...you want to obtain yeast growth...there fore you need air . Leave it loosely covered . Never seal the jar.
Your yeast is just fine with no fruit in it while it is stored. I have a thick " mother" in the bottom of my jar of apple yeast water. It gets mixed in when I pour off some to use to bake. It then settles again. You will feed with fresh fruit and put your YW somewhere warm for a few hours and it will be good to go. Excellent as a matter of fact.
Anyone who thinks that only flour and water combinations give you viable yeast to bake are mistaken. Yeast is everywhere . I will say that in a kitchen where much baking and cooking activity is going on the presence of more yeasts is likely. But one isn't going to plate them to see what is what...at least I am not. I am satisfied that my flour /rye levain that is almost 10 years old is distinct in many ways from my apple yeast water....and similar in others.
Dan you would be making a mistake to give your YW anything but fruit...whatever kind you like and no it doesn't have to be anything but clean. Don't use any sugars...stick with half and apple or half of a banana etc....c
"Sourdough is a dough containing a Lactobacillus culture in symbiotic combination with yeasts. It is one of the principal means of biological leavening in bread baking, the others using cultivated forms of yeast. It is important in baking rye-based breads, where yeast does not produce comparable results"
Thanks, Caroline for the thorough reply.
You wrote, “Don't use any sugars...stick with half and apple or half of a banana etc....” I assume the yeast is on the outer skin. Is it correct that the skin supplies additional yeast and the insides of bananas and apples provide sugars (fructose)?
I have been keeping mine sealed and gave it unprocessed sugar every once on a while. I started the YW months ago with very little information. They seem very easy to start and maintain.
Thanks for the help.
Danny
you are only supplying food for the yeast population that exists in your YW that is currently in storage. It gains strength and multiplies from the feedings of fruit/vegetable/herb etc. You don't need peeling for that. I found with my YW that sugar and or honey made it get weaker so that is why I say not to use any form of additional sweetener , use only fruit or vegetable. I think what happens if you use sweetener is it speeds up the processes much like you eating a teaspoon of honey vs eating the equivalent in real food. I am not a food scientist...don't even play one in the movies LOL ! Vigorously stirring aerates the yeasts as well and giving it food strengthens and helps the population multiply. I have never put banana peel in my YW only the fruit. I do leave the skin on any other fruit I use but I wash it before I put it in the YW. My hands and the air in my kitchen are covered with yeasts from all the activity in my kitchen . There is no shortage of population I am sure in your kitchen and on your person so there is no need to concern yourself with adding to the population. All you are doing is changing the original flavor profile of the YW by changing the fruit/vegetable /herb etc that you give to your YW or feeding it the same fruit is just maintaining the original. When I want to change the flavor I just take out a few ounces of my AYW, after stirring up the mother, and put it in a new container and add the new flavor and more water. That 's it. In a few hours I have a new YW to work with. My YW when mixed with flour grows astoundingly fast ! Triples at least in a few hours. I use it very young when I am making a levain with flour/YW. If I am using just my basic apple YW and not making a levain then I just take out my original container and feed it and wait a couple hours and use out of it. My breads with YW rise almost as fast as they do with regular yeast. I have to be careful not to over proof. I hope this all makes sense. I know you love to delve into the whys and wherefores. I'm no help with that. I just mix things up and they do what I want them to do....or occasionally NOT....but I have a loose grasp of why :) I'm mostly lucky I guess ! Hope you will post back with your results. c
Yes! I can definitely help.
For baking bread, a good sourdough starter made only from flour and water is superior. Commercial bread yeast is also superior to the yeast water, in every way except one - novelty value, being able to say you did it.
If your yeast water is for non-baking purposes, then go according to those purposes.
since you have no experience with yeast water I think for you to speak to its efficacy is of no value. I have been baking all our breads since the mid ‘70’s. There isn’t much I haven’t tried. The quality of YW breads is very much improved over commercial yeast and straight sourdough. The flavor, texture of the crumb and the length of time it stays fresh are all greatly enhanced.
my tuppence. Ive made both apple yeast water and raisin yeast water. Both were non-organic. very easy to make and i made lovely breads with them. I love the idea of making yeast waters from different plants, etc - theres a baker in England who uses flowers however i already have a rye mother and a barm mother in the fridge and if i keep it up ill be a broken man from all the feeding. So as i understand yeast is everywhere - makes sense to me, especially if youre baking all the time. the problem as i see it is having endless avenues of exploration. But then thats the joy.
so many breads so little time! I keep minimal amounts of two starters... one with YW/ flour and one with my original SD culture and then a jar of YW. If/ when I want something specific for another adventure such as my chocolate SD culture I use it all so no extras left to deal with. Thank you for chiming in and happy exploring!