How to Cultivate Your Own Yeast

Some of the links in this post may contain affiliate links for your convenience. As an Amazon associate I earn from qualifying purchases.

how to cultivate yeastWheat berries tend to be a large part of most peoples’ food storage plans, with the assumption that the wheat will become bread. Wheat is an excellent food storage candidate because it keeps its nutrition for a very long time – up to 30 years under the right conditions. You can’t make bread with only wheat, though! Ideally you will have at least some salt and some kind of fat – oil or butter. But the crucial ingredient that makes bread bread is yeast.

Most commercially available yeast is one particular strain of Saccharomyces cerevisiae. Anyone who bakes is probably intimately familiar with it – it comes in beige granules and is generally kept in the fridge or freezer for long-term storage. Yeast is a live organism – in its dry form it is kept in a dormant state. Keeping it at low temperatures will extend the life of the yeast dramatically. (Note: if you try to make bread from yeast inherited from your grandmother that has an expiration date of 11 years previously, prepare for disappointment.) 

When all is said and done, however, cultivated yeast like S. cerevisiae is a consumable product. And when it comes to consumable products, the question on every prepper’s mind is “What will I do when I run out?”

You can make your own yeast

It is not only possible, but quite simple, to produce your own yeast for bread-making. Off the top of my head, I can think of four methods.

All of these can be considered “sourdough,” because you are cultivating strains of wild yeast for bread making. Sourdough is extremely useful, but it is not a passive kitchen ingredient that can be kept quietly in your refrigerator, forgotten until needed. A healthy sourdough starter must be cared for and treated almost like a pet: woken up in the morning and put to bed at night, and fed regularly.

Caring for and using sourdough involves something of a learning curve. If sourdough yeast is a part of your long-term emergency preparedness plans, don’t procrastinate becoming familiar with it. Be aware, also, that any method of procuring sourdough (short of getting a bit of starter from a friend) will take several days.

It took me several tries to figure it out. The first time, I thought I could keep it in a mason jar, but it “escaped,” as it were, and made a glorious mess in my kitchen. The second time, I tried keeping it in my fridge and it died on me. The third time, I had it for a whole week before the yeast stopped metabolizing the sugars in the flour and started eating the protein. I could tell because it started smelling like paint. No, I am not making that up. I don’t currently have a live sourdough starter, but I know I could obtain one should the need arise.

Method One: Put Your Starter Underneath an Apple Tree

This was commonly used in medieval times. It sounds like an old wives’ tale, but actually can be very effective. Many fruits have yeast cultures growing on the skins. Apple growers refer to the yeast on apples as the “bloom.” When bread dough is placed underneath an apple tree, bits of the bloom flake off and fall into the dough, allowing it to rise. The disadvantage to this method is obvious: if yeast can get into your dough when it’s outside in glorious nature, so can less tasty items like sticks, leaves, dirt, and bird droppings.

But if you like the idea of using apples, you can try this other method which uses just the skins in the relative safety of your kitchen. Organic fruit is best, because the micro-organisms on the skins haven’t been sprayed and/ or washed off.

Method Two: Raisin Yeast Water

Raisins are another fruit that have yeast growing on the skins. This is very similar to the apple skin method; just use raisins instead of apple peelings. You’ll find instructions for making yeast out of raisin water here. The advantage of using yeast obtained by this method is that it doesn’t give your baked goods any residual flavors. Sourdough bread can be, well, sour. And some can be really sour.

Method Three: Potatoes and Hops

Here’s an unusual method taken from Housekeeping in Old Virginia, copyright 1879:

Boil one quart of Irish potatoes in three quarts of water. When done, take out the potatoes, one by one, on a fork, peel and mash them fine, in a tray, with a large iron spoon, leaving the boiling water on the stove during the process. Throw in this water a handful of hops, which must scald, not boil, as it turns the tea very dark to let the hops boil.

Add to the mashed potatoes a heaping teacupful of powdered white sugar and half a teacupful of salt; then slowly stir in the strained hop tea, so that there will be no lumps. When milk-warm add a teacupful of yeast and pour into glass fruit jars, or large, clear glass bottles, to ferment, being careful not to close them tightly. Set in a warm place in winter, a cool one in summer. In six hours it will be ready for use, and at the end of that time the jar or bottle must be securely closed. Keep in a cold room in winter, and in the refrigerator in summer. This yeast will keep two weeks in winter and one week in summer. Bread made from it is always sweet.

This method is not exactly sourdough, per se, because one of the ingredients is yeast. I have not tried this method because, wouldn’t you know, I’m always fresh out of hops at my house. Like most things, hops and brewer’s yeast also, if you feel so inclined, is readily available from specialty retailers.

Housekeeping in Old Virginia has several methods for procuring yeast, and all of them involve yeast as an ingredient. For more specific instructions for making yeast out of potatoes, click here.

Method Four: Capture Yeast From The Air

This is the most traditional of all the traditional methods of obtaining yeast. Make a thin batter of flour and water (freshly ground flour is considered to be best) and let it stand in a warm place until it ferments and bubbles form. If you have a squeaky-clean house with no micro-organisms or anything present, you may have some difficulty with this. Because I am kind of a slob, this has never been a problem for me. Some people advocate spitting into the starter to “jump start it,” but the general consensus is that this is gross and a demonstration of poor hygiene.

I like keeping my yeast mixture outside when the temperatures are warm enough but not terribly hot as there is naturally more yeast in the outside air than inside my home.

The very best resource I know of with information about the care, keeping, and use of sourdough can be found at Sourdough Home.  There is so much more to sourdough than merely obtaining your yeast. No matter what method you use to gain your starter, you’ll want to spend some time reading up on how to sustain it. Sourdough is more than a kind of bread – it’s a way of life.

how to cultivate yeast

19 thoughts on “How to Cultivate Your Own Yeast”

  1. Pingback: Prepper News Watch for October 19, 2015 | The Preparedness Podcast

  2. Now I’m going to have to plant apple trees, or buy brown bread in a can. To go with my cheese whiz in a can, if I don’t get canned cheese. I appreciate the history touch.

  3. Hahaha… Fresh out of hops! Made me chuckle! I must attempt sour dough again soon. The “gotta treat it like a pet” syndrome definitely turns me off. But, the yummy bread…. might be worth it! Thanks. Great article.

  4. But how do you use it? Do you have a recipe for the flour yeast? I can make the yeast, but no clue how much to how much of the other ingredients. Doesn’t work like regular yeast. Help

    1. I’m glad you asked, Kathy! All of this yeast can be used as any sourdough starter. It’s not like the dormant granule yeast that you only need 2 1/2 Tbsp for a batch of bread. If you take a look at an average sourdough recipe, you’ll see that it calls for “1 c sourdough starter.”

      Don’t assume that bread is the only thing you can make out of sourdough, either – I’ve seen recipes for donuts, pancakes, biscuits, scones, muffins, and many more.

  5. i just have to tell you that i LOVE your “commercial” about preparedness utilizing clips from WW Z. very ingenious!! on another note, i have been nursing a sourdough starter for several months now and it’s hung on!! one very valuable lesson i learned… NOT store it covered with cheesecloth if you have a batch of kombucha in the same room. the kombucha scoby kills the sourdough, don’t ask me why. i used the method from king arthur flour (freshly milling my rye flour to start it), and store it in a glass jar with a plastic lid, and it’s quite happy 🙂 i’ve yet to bake with it, but that’s my goal…..someday….hopefully soon 🙂

  6. Before I was diagnosed with Celiac disease I had a sourdough starter that I called Gladys. Gladys made some wonderful bread and pastries but she ended up going bad after about 6 months. I have read that I can make a sourdough starter with non-wheat flours but have yet to try it.

    1. If you have success using non-wheat flours, please do let us know! That would be exceedingly good information to have.

  7. For many years, I have made and enjoyed my grandmother’s recipe for “Salt Rising Bread”. The cultivated yeast for this bread comes from potatoes and does not need to be fed or maintained. This has never failed to rise for me.
    1. At noon the day before baking, slice two medium potatoes in a quart jar.
    2. Add 2 tablespoons of white cornmeal, 2 tablespoons of white sugar and a small “pinch” of baking soda.
    3. Pour 2 cups of boiling water into jar, put on cap but do not seal tightly.
    4. Set in a warm place until morning, when about 1 inch of foam should be on the top of the fluid. It should have a distinctive odor.
    5. Scald 1 quart of milk and cool to room temperature.
    6. Add to the milk, 2 tablespoons of white sugar, a small pinch of baking soda and 1 cup of the liquid from the quart jar of potato slices.
    7. Add enough white flour to make a batter and set this in a warm place to double.
    8. When batter doubles, add 2 teaspoons of salt, shortening the size of a small egg, 1 tablespoon of sugar and enough white flour to make dough.
    9. Knead for 20 minutes.
    10. Make into four loaves, placed in greased pans (41/2″ x 81/2″) to rise.
    11. Let rise in warm place til double.
    12. Bake at 350 degrees for one hour. Delicious!

    1. I have one question – do you need to also peel the potatoes, or just slice them? I will have to make this soon; I am re-reading the Little House books, and salt-rising bread is one of the delicious foods mentioned. I can’t wait to try it!

    2. Thanks for this recipe Susan. Sourdough and my tummy do NOT get a long, so this would be a great way for me to make my own yeast and bread! I will definitely give this a try.
      And thank you Beth for such great information! I’ve made homemade breads many times, and yet have never made my own yeast and have lately been wondering about this very topic.

  8. Beth, I peel my potatoes and sliced them thinly. I never tried scrubbing and then slicing them. Next time, I will prepare two quart canning jars of the mixture. One with peeled, slice potatoes and one with scrubbed, sliced potatoes.

    We cleaned the chimney this morning. Will soon lay a fire for the season and our mantel will become our dough rising location.

  9. sometimes I am too hurry so I decided to use a little drop of dry yeast, I put in water + sugar + warm place and in 1 hour I had enough yeast to cook a bread.
    I use sourdough too(collected from air), when I am planning to cook a bread for next day.

    To keep the sourdough for long in a passive kitchen, my grandma was selecting a part of the path (before bake!! ) and do a very thin “paper” of this and dry it. In several hours is dry, so you can break with hands ( is like dried bread + flour ) and put in a paper bag. When you need just re-hydratate 2-4 days before, and feed like usual every 12 hours

    These solutions stopped to be used in the last 100years because of the commercial yeast, but here is expensive ( around 25 cents for fresh yeast, used for a bread), and I calculate : 2 weekly breads x 0.25 x 50 weeks …. I can save some money every year.

  10. Pingback: Breaking Through Writer’s Block – Part 1 | Beth Buck, Author

  11. I’m a very novice baker and have some questions. when you refer to “sourdough starter” does this only make sourdough bread or can it be used to make any type of bread?

    if your bread recipe calls for 1 TB yeast (store bought) how much homemade starter is that equal to?

    some info says when kneading dough to flour your surface, others say not necessary. Which do you prefer?

    Thanks for the help. I need all I can get.

    1. The Survival Mom

      Linda, use sourdough starter only for sourdough bread recipes. I recommend using the sourdough recipe link in my article. For other yeast bread recipes, use either the potato or raisin/fruit yeast mixtures.

      There’s not an exact equivalent with store bought yeast and the starter yeast. In my instructions I suggest trying 1 cup of the yeast starter liquid in place of 1 cup of liquid called for in the bread ingredients. Read my instructions again since there’s a lot of trial-and-error for your first couple of loaves.

      I do like to use a lightly floured surface when I knead my bread dough.

Leave a Comment

Your email address will not be published. Required fields are marked *