My Kitchen Could Be a Yeast Farm


One of the many lightbulb moments for me in Michael Pollan's book The Omnivore's Dilemma came when the author harvested his own yeast to make bread. I'm always on the lookout for ways to replace items I currently pay for with free or cheaper versions of the same. But when I read about harvesting yeast, I pictured heading out to a stream in the woods, scraping fungus off wet rocks or something like that.

Turns out it's nothing so difficult. Yeast for making bread can be harvested from the air right in your kitchen or backyard.

People do it not just to save money but to develop unique bread that is a truly local cuisine. Pollan doesn't give very specific instructions for harvesting yeast from the air, but naturally, plenty of people on the Internet do.

According to this article, wild yeast is not exactly the same fungus as the dried yeast we buy in the grocery store, but it is pretty close. Every recipe I found for gathering and using wild yeast resulted in a sourdough starter -- that dish of doughy stuff credited with keeping settlers alive in the days of California's '49ers. It's not clear to me if it's possible to make bread that isn't sour with wild yeast -- but personally I don't care because I like sourdough better.

The nice thing about making your own starter is that, if it works, you only have to do it once. Here's an account of a woman who kept her starter going for 15 years. Now, I may only pay about $5 for a month's supply of yeast (I've been making my own bread in the machine several times a week), but extrapolated over a decade, I could save $500.

If you live in the Bay Area, your wild-harvested yeast may make a bread tasting very similar to sourdough you buy in the store. If you live somewhere else, you might end up with a different flavor. That is, if the yeast in homemade starters truly does come from the air; this site suggests that it really comes from yeast already present in the flour used.

As I look over various reports of experiments with sourdough, it's clear that this is a little science experiment; not a very difficult one, but one for someone more interested in the process than in tidy, speedy results. It's also an experiment that requires a little courage. I'm a food-poisoning-fearing girl, and the idea of setting out some bland, wet food product for days to encourage the growth of fungus and bacteria is a little unsettling. The experience of the top poster in this discussion did nothing to assuage my fears -- her starter turnedhe going advice online is to discard any starter that starts smelling aggressively foul or non-foodlike. An alcoholic, beery smell, on the other hand, sounds quite normal.

Instructions for getting started:

This step-by-step from the Bay Area includes helpful photos for how your starter should look, and precise instructions for when to put some of the starter into the fridge to save for a future batch.

While many sites are quite general in their instructions, The Fresh Loaf offers precise measurements, which I plan to follow when I try my own starter. This site also offers a solution to a common problem -- many first-time yeast gatherers complain that their yeast seems to "die" after a few days, but according to The Fresh Loaf, it just needs a little cider to adjust the pH and get things growing again.

Not feeling so adventurous? There's another way to get yourself a starter that you can milk for decades and never have to buy yeast again -- buy or borrow some starter from a more experienced baker and fungus farmer. Here's a site that sells the stuff (note: I haven't vetted this company), and this site will even mail you some dried starter, derived from a historical strain, free of charge.

And by the way, once you have a good starter going, you can make the bread right in the bread machine.

Further reading:

This usenet posting contains lots and lots of information on managing starters old and new.

Books with instructions on making and maintainng a starter include:

Adventures in Sourdough Cooking and Baking

Simple Sourdough

Note: This entry contains affiliate links.






Disclaimer: The links and mentions on this site may be affiliate links. But they do not affect the actual opinions and recommendations of the authors.

Wise Bread is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to

Guest's picture

It seems like it would be easier to buy a large bulk pack of yeast at warehouse clubs like Costco or Sam's Club. Much less expensive than regular supermarket yeast and saves time over making your own. You'll have enough yeast for years of use.

Guest's picture
Rob O.

My Mom passed away earlier this year and so when time to make Christmas dinner came around, it wasn't going to be the same without Mom and her homemade yeast rolls.

Unfortunately, Mom's recipe was totally memorized, so it went with her. I found a recipe that didn't seem too difficult so I summoned up lots of courage and decided to try making yeast rolls from scratch for Christmas dinner. Thankfully, the outcome was edible, but they weren't nearly as fluffy or tasty as Mom's usually were.

I don't think I'm quite ready to tackle making my own yeast nor do I think I'll be doing this often enough to get that hardcore about it (we don't typically eat a lot of bread around our house) but now that I'm past being quite so intimidated by the whole process, I would like to find a recipe that'd yield a more worthwhile result. Could you recommend a good recipe for making reasonably simple yeast rolls?

Guest's picture

If you have one batch of commercial yeast, just make a flour and water sponge with it and save some of the sponge for your next batch of bread. You never need to buy another package of yeast if you do this. Plus it will gradually gain sourdough notes as bacteria begin to populate the sponnge over time, metabolizing the starches into energy for them and lactic acid and other metabolic byproducts for the dough.

You will need to feed it fresh flour and an equal amount of filtered water (or water that has stood out for 12 hours or so to dissipate chlorine) about once a week, leaving it at room temp for about 8 hours or so, and refrigerate it for most of the rst of the time.

RE: sourdough and wild yeasts:

sourdough is actually a combination of yeast organisms and bacteria (similar to the bacteria that produce yogurt).

simplistically put, the yeast organisms create the CO2 which make rise in the bread, and the bacteria produce the sourness.

It is possible to produce a wild-fermented bread dough that is not pronoundedly sour. You would do this by keeping the dough at a temperature that advantages the yeast over the bacteria.

the bacteria are at an advantage at some temperatures, while the yeast have the metabolic advantage at other temperatures. Off the top of my head I don't know them so I won't potentially mislead by specifying right now. I will say that once the dough is formed, you can put it in the fridge and let it ferment there for about 24 hours. This is a nouvelle-cuisine baking method for making old-style hearth bread. The technique is called temperature retardation (of the fermentation) and it gives a much more complex and rounded flavor than a straight room-temp. rise. Try it.

As a rule of thumb, for every drop of temp of 10F, down to about 36 degrees, yeast activity halves. So a 2 hour rise at 70F becomes a 4 hour rise at 60, an 8 hr rise at 50, and a 16 hr rise at 40F.

Guest's picture

Ok, proper starter can take up to 12 days to create.

1)1/2 cup flour, 1/2 cup water. mix. Let sit for about 24 hours. Incidentally, rye flour makes an excellent first flour for making a starter from scratch for some reason.

2) begin discarding half of the starter, then replacing the discarded amount with the same 1/2 cup flour and 1/2 cup water. do this every 8 or 12 hours over about 5 or 6 days.

It will get very bubbly. When you smell it it may give off scent of fresh paint, alcohol, plaster, or other smells, which will change as the starter gets more mature over the course of the week. This is normal and due to the byproducts of the metabolism of the starter. If it smells *BAD* then it is going off. Which has never happened to me.

Once it is able to double its volume in 8 hours, it is strong enough to leaven a loaf of bread and you can use it.

Use half of it for your recipe, and the other half to save in the fridge after refreshing it with flour and water and letting it sit at room temp for several hours.

I have personally never seen a starter turn green or red or whatever, but if it does throw it out.

If it is stored in the fridge for months and months it may get a darkish layer on top, which you can scrape off it.

Many bakers actually start a new starter every 6 months or so, as they prefer the newer starter to older ones. So keeping one going for 15 years is not necessary, even if might be fun.

Guest's picture

I thought I was doing well by occasionally baking my own bread using one of those no-knead recipes. Making my own yeast starter never even crossed my mind. I'll have to give this a try sometime since I really like sourdough.

Myscha Theriault's picture

You know, I just don't think I'm "there" yet Carrie, but this is certainly inspirational. I snag the bulk yeast from Costco or Sam's as the person above recommended. It's interesting you mentioned the old gold miners though. So, they actually grabbed their yeast out of the air to start theirs as well? OK, I've reached the point of rambling. I just wanted to say congratulations on an interesting article.

Guest's picture

I have been thinking about starting this off and on for a few years but have not tried doing it yet. A jar of yeast costs $6 and we go through them pretty quick since we bake our own bread.

Guest's picture

$5 per month for yeast is an outrageous amount of money, unless you're making a ton of bread. I make all the bread that two adults can eat, plus sell a few loaves on the side, and I use less than $3 worth of yeast per year!

Those little packages of yeast are ridiculously expensive compared to bulk yeast, either instant or active dry. I buy it in bulk, store it in the freezer, and a $3 bag (about a pound) will last me for about 18 months. No need to worry about it losing potency when it's stored in the freezer.

I won't argue the qualities of sourdough bread - it's fantastic. But I've found through experience that sourdough starter is much less predictable and reliable than having a stash of yeast in the freezer. At bulk prices, I think that reliability and consistency is *well* worth the expense.

Guest's picture

I really like this idea, I will give it a try. I also wanted to add that the cheapest way by far (that I know) to buy yeast is to go to your natural foods store and buy it bulk. I can buy more yeast that way than in those jars at the supermarket, and actually pay anywhere from one to two dollars.

Debbie Dragon's picture

Have you ever made the friendship sourdough bread from the Omish?  It's delicious.  They call it friendship bread, because each time someone makes it they end up making 4 starter loaves that can be saved or given to friends to continue the process of making bread.  I have only ever made it from a ziplock bag full of 'starter' stuff, so I'm not sure if it contains yeast at first or if it just makes it's own.  But even if you have to buy yeast to make the first batch, subsequent loaves don't require more yeast, so you could theoretically go on forever just adding milk and sugar to your starters!

Philip Brewer's picture

Once you get a starter going (whether you harvest wild yeast, get some from a friend, or buy some dried starter from one of the many places listed above), keeping it going is so fun and easy, I don't understand why everyone doesn't do it.

We bought a starter culture from some place out in San Francisco, and have had the same one going for years now.  She's really a pet.  (We call her Bubbles.)

We used to buy bulk yeast, which is cheap enough to not be a burden--but since rasing Bubbles is free and easy, it seems like a no-brainer.

Anytime we want to make something with yeast, we take Bubbles out of the fridge and put her in a big bowl.  We add as much water as is needed for our recipe, and then add in a bit less all-purpose flour than we added water.  Then we let Bubbles feast on that for a while (typically all morning, but 20 minutes is long enough if you're in a rush).  Then we pour Bubbles back into the jar where she lives (wash the jar while it's empty) and put her back in the fridge.  What we didn't pour back goes on to make our bread or whatever--you can just about follow an ordinary recipe at this point, adjusting for the fact that the liquid already contains the water, the yeast, and some of the flour.

Besides being free, we never run out--one less thing to keep track of.  Besides, she's kind of a member of the family.  On top of all that--wonderful sourdough flavor!

Guest's picture

Just a note about buying "historical" starter:
As the culture grows, it will gradually become completely local, as yeast and bacteria from the air where you live will out-compete the foreign ones from the original starter. So (unless you live in San Francisco), you won't be making San Francisco sourdough after the first few loaves.

Guest's picture

I'm convinced that we capture wild yeast from the air. I've been baking bread for longer than I suspect you've been alive, both "regular" and sourdough. Several years ago, after always having lived in old houses, we moved into a brand new condo and I couldn't figure out why my sourdough wasn't behaving as I expected. It took several months before I could turn out a good sourdough loaf.

So, there's my anecdotal evidence to support that theory.

Guest's picture

A friend, who is a baker, brought back a yeast/sourdough culture from a well-known Parisian bakery (Poilane, I think). He is still using the "offspring" of that culture, but he said that over time it has changed. The change was fairly rapid at first, and it's pretty stable now, years later. Apparently the yeast & bacteria in the original culture either adapted to his conditions or (more likely, imho) they were gradually replaced by local strains.

Buying a culture still gets you past the possible "pink and green" phase, and that in itself might be worth it.

Guest's picture

Any beer lovers out there already know that the Lambic style of beer is characterized by it's use of "wild" yeast, or frankly, whatever is floating around in the air wherever you happen to be making said beer. The regional differences between the strains produce different flavors. Most commercial brewers jealously replicate "their" yeast strains under carefully controlled conditions so that they may achieve consistent results.

Here's an example, going back 500 or so years:

Guest's picture

I highly recommend the King Arthur Cookbook to learn about sourdough. There’s a day-by-day instruction section on starting a sourdough. Sourdough for dummies if you will. Also, the recipes are suburb. I use the recipe for sourdough waffles when I feed the starter that way nothing goes to waste.

Guest's picture

Wow, I learned a lot from the post and comments. Will have to explore sourdough and maybe even the starter.

I thought I was doing good with my frugal pancake recipe. This takes the cake.

Guest's picture

As we have become more cautious in my family over the things we eat, eating non processed foods and leaning more to all natural things, I noticed the yeast that we use to make our bread... small round uniform circles, not exactley "natural" U could never figure out how they were made either. So I have been scratching my head wondering how can I do this without using that stuff? Here it is! Very Interesting, the answer was in my backyard!

Guest's picture

You inspired me. I haven't had a sourdough starter for years, since I forgot to put mine back in the fridge before I went away for the weekend. It was a very healthy starter and ran rampant all over my kitchen counter and down onto the floor. It was lost in the cleanup, and I was strongly encouraged not to start a new one. =D But now there is a new, happy, bubbly Herman in my kitchen, almost ready to go into the fridge. Thanks for reminding me.

Guest's picture

As I understand the situation, there are three kinds of yeast I might be interested in raising:

* baker's yeast, which you describe here. This yeast produces abundant CO2, needed to cause bread to rise;

* brewer's yeast, used for making beer, which produces Ethanol up to about 6%, at which point the yeast is killed by its own waste (the Ethanol);

* wine yeast, used for making wine, which thrives producing Ethanol up to 20%. This is quite expensive;

Do you know if brewer's or wine yeast can be similarly maintained?

Thanks. I love Wisebread!