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Fermenting is a science, and a bit of an art. It requires care in a few specific things, but doing it right is not particularly complicated. We provide instructions that are accurate to the best of our knowledge, and which are based on the methods we successfully practice ourselves. There are no guarantees of success or safety with fermented foods. While properly fermented foods are not only safe, but healthy to eat, it is up to you to follow instructions to ensure safety, and to trust your eyes and nose, and don't eat things that do not look or smell like food. We offer no guarantees of success with our product. We do warrant that it is as described, and will do what we say it will, but how you use it is your choice.

Sourdough starter is like having a pet (only not cuddly). You feed it and take care of it, and it gives you something back. You never have to buy yeast again, and you get awesome slow bread.

I’ve run into a number of different methods for starting sourdough starter. Some of them make it sound terribly confusing. It isn’t really, you only need two things:

  1. Flour. Whole wheat works best. The fresher the better. Wheat germ in the wheat helps. Rye, barley, oat, or rice flour may also be used, but some kinds may require more than just two ingredients.
  2. Water. Clean as you can get. Non-chlorinated is best, but low chlorine amounts won’t hurt.

Start small – half a cup flour, a little less than half a cup of water. Should be stirable, but stiff. Put it in at least a quart jar. Cover it with a cloth, or something else that lets air circulate (Fermenta Caps work great. Fermenta Lock is not for starting sourdough).

Watch it. When it gets bubbles (12-24 hours, usually), give it another half cup flour, and a little less than half a cup of water. Stir it again. Don’t worry if there are lumps, they’ll work themselves out as it fizzes.

Now, every 12 hours you need to feed it. Before you think this is going to be too much work, relax. You don’t have to do this forever, just until it is established. And it doesn’t have to be every 12 hours on the dot, just twice a day – morning and night. You can do that!

To feed it, remove half, replace with half a cup of flour and a little less than half a cup of water. Yes, it will get the jar messy. Put it in a clean jar every other day or so. That will help it not look so nasty, and keep mold from getting hold on the sides.

Keep watching it.

First it bubbles (that was your cue to start feeding it), and next it starts to grow – that is, it will expand, and then deflate as the bubbles rise and then burst and slow down again. It does this on a cycle. Once it starts to deflate, that means it no longer has enough food to keep growing. It may “peak” and reach the high point when you are not there, but you’ll see streaks on the side of the jar, and a “high water mark” where it came up to. You don’t have to feed it as soon as it starts to deflate, it will just slow down. Let it go too long though, and you’ll starve it, mold will take over, and poof, you’ve just killed it! This is why you feed it twice a day – to keep it from starving.

Second, you watch how MUCH it bubbles. It will rise more and more each day if it is happy. When it gets to the point where it is doubling each day, you can use it for bread or whatever else you want to bake.

Now, the other factor you can pay attention to is the SMELL. Sourdough starter can smell really funky at the beginning. Nasty stale stuff that does not AT ALL smell like what you are aiming for. Bear with it. It gets better, though not necessarly how you expect!

After about three days, or maybe four, it will no longer smell so funky, and will smell alcoholic instead. Bread does form alcohol when yeasts digest the flour – not a problem, because it all cooks out when you bake it. But if you’ve done baking, you’ll recognize the sharp alcohol smell of rising bread. It may take a little longer to smell yeasty – that other more comforting smell associated with yeast dough. Let it go through the phases.

Once you have it well established (give it two weeks or more), you can put it in the refrigerator for a week or two at a time. Don’t go longer than that without taking it out, feeding it, and letting it sit on the counter overnight before you put it back into cold storage.

Any time you want to use it, you need to feed it, leave it at room temp 12 hours or so, then remove what you need to use. If you need to feed it but do not want to cook, remove half, then feed it (so you have to feed it less – you should be feeding it about as much as is already in there).

Ok, so once you have that down, there are some variations which are easy to experiment with. You see, there are different ways to make sourdough, and all of them produce a slightly different end product! What you put IN it has more to do with what it IS than the air around it.

A well established sourdough is hard to budge through the influence of airborne yeasts – there is simply too much already established in it. But young ones can be easily influenced in one direction or another.

Many recipes call for adding commercial yeast. Honestly there is no reason to do that. It just isn’t needed, and it will harm more than it helps. When I start a sourdough, I want to do it without 20th century influences if I can. I mean, why should I use 20th century shortcuts when I am trying to recreate something that is meant to produce breads in the manner in which they were baked BEFORE those shortcuts were available? I can be a bit obstinate about authenticity, but I also don’t like paying for things that should not be necessary if the truly traditional method is used, and I know that often when we take a shortcut, there is a trade-off that we didn’t really want – and this is true of using commercial yeast as well.

Baker’s Fast Rise (Active Dry Yeast) is not the same as the yeasts that grow in your sourdough. It is not symbiotic with the bacteria in quite the same way. It will tend to dominate and take over your starter, and you will never have starter that develops quite the same character as you will without it. Overblown commercial yeast tends to go dramatically sour, and tends to not taste flavorful like true sourdough. Give me the good stuff… give me the ability to control it naturally.

There are other things that are also recommended to get a faster start, and which will affect the long term sourdough that is produced, because they influence the kind of yeasts and bacteria that establish in the starter. Some of them are natural – again, they won’t give you the same kind of sourdough you’d get from just flour and water, but sometimes that may be a good thing. Other additives can affect the outcome and flavor as well.

So what are some of the variables? What can you have some fun with?

  • Milk Kefir – adding this can change the yeast balance, and affect the resulting sourdough starter. It can also help when you have stubborn flour.
  • Wheat berries – if you are using commercial flour, it can be stubborn to start. A tablespoonful of wheat berries can put some nice natural yeasts into the starter, allowing it to start without adding other things, producing a pure historic sourdough. By the time you get to the point of using it, you will have thrown most of the berries out, and the ones that are left will soften when cooked, so they won’t hurt your teeth or anything.
  • Water Kefir – if you let water kefir ferment past the alcoholic stage, you get a very bready smelling liquid. If you use that instead of water on the first mixture, it can jumpstart your sourdough starter. It will also affect the long term outcome. It can help to broaden the spectrum of available yeasts in the sourdough, and may be especially useful for low gluten grains.
  • Wheat Germ – traditional sourdough used milled flour with the germ. The components in the germ will encourage a broader complement of microbes in the starter, and make it more like “caveman bread”. If you are not able to use fresh milled wheat, a tablespoonful of Wheat Germ every other day or so can help to get a more complex flavor and more vigor in your sourdough.
  • Different types of flour – Rye flour, barley flour, spelt, durum wheat, hard red or hard white wheat, rice flour, oat flour, etc. Addition of other flour types to a starter can change the long term flavor. Alternately you can make the starter from other types and then maintain it on them also. If the sourdough starter is bubbling up nicely in the jar, then it will raise that kind of flour – which is a nice way to tell if your starter is going to raise what you want to bake. This can also help in trying to recreate a regional flavor – consider what grains they used historically in that region. Many areas used very coarse red wheat, some used barley and wheat blends, many used rye. Some used different flours during different times of the year, or according to availability and price. Many areas used blends of flours. This is a major influence on the flavor and qualities of a starter – various grains encourage the growth of different strains of yeast and bacteria, so it can affect both flavor and performance. In general, whole grains produce more sour than refined grains.

If you have a starter that is established that just isn’t quite what you want it to be, you can also separate off half, and test it with different things, and see if you can come up with something closer to what you were hoping for. Starters can be very sour, very mild, fast rising, slow rising, they can raise whole wheat or rye or white bread better than anything else, they can be gluten free or organic. They are all similar and recognizable as sourdough, but also distinctly different. Immitate one you like, or branch out with something completely new!

Have some fun with it, and feel free to experiment. That is one of the beauties of starting sourdough starter yourself – you can play with it until you get it just right.

Once you have it going, it is fairly low maintenance, as long as you are baking once a week anyway.

You, like the Yukon Sourdoughs, may find that you’d rather give up anything rather than give up your sourdough pot! But you don’t have to sleep with it to keep it warm…

The ORIGINAL one-way valve fermenting airlock! Imitation IS the sincerest form of flattery, and we have noticed that our product has been copied by other sellers of fermenting products. Remember, if you see someone else selling a one-way valve airlock for fermenting, THEY copied US, not the other way around! Fermenta Lock is still the only original invention, handmade in the US. If it isn't orange, it isn't the original!

We invented Fermenta Lock, Fermenta Free, and the valve used for Fermenta Fido and other Fermenta Airlock products. We invented Fermenta Dunk Extender. Patents are prohibitively expensive, and designed by the government not to protect the rights of individuals, but to provide another source of revenue and control for the government and lawyers. We are good at what we do. We have endless ideas and endless creativity, and competition does not scare us. Impatient thieves do not scare us - they are too busy taking shortcuts to make a success of it anyway, and they won't want to take the effort to actually MAKE a product and fill orders.

So if you want to copy our idea, go right ahead. If you want to market and sell a competing product, you are welcome to do so, as long as you do not patent our idea - we had it first, and our posts on FaceBook announcing the invention and launch of it will prove that. This idea is officially in the public domain, placed there by us. We will NOT release supply sources, or part names unless you want to buy them - we'll be happy to sell you an instruction kit. If you buy our product, or look at the images and figure it out for yourself, good on you. Compete with us if you like, just don't screw us, and we'll get along just fine. Big companies who might want to screw us may have more money, and more lawyers than we do, but we have more to gain by suing the pants off a big company, and believe me, we will be well motivated to do so if anyone patents our idea and claims it as their own - this is a free idea. Everybody now owns it.

Published June 23, 2012

Wholesale, Export, and Manufacture of this product by other companies is an option. International distributorships are available for those wishing to export. Please email us to inquire about access to our wholesale website, or in regards to manufacturing any of our products.

Business Building Services Are Available - If you are wanting to build a business like this, where you make things in the home and sell them direct to the customer, or if you want to build a business that you can sell to other people as a complete business package, Firelight Heritage Farm is now offering Cottage Industry Services to aid small business owners in building a successful product or service business from the home. Don't know what you want to do? We can help you figure that out too (something original, and just yours, not a canned business). You get the wisdom and uniquely successful perspective and experience of people who have been business, marketing, and website professionals for more than a dozen years. For more information, visit Why copy someone else's business when you can do something uniquely you and enjoy it so much more?

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Uses of Fermenta Lock

Fermenta Lock is a compact airlock cap for mason jars, to help in making old fashioned brined pickles, and other lacto-fermented foods. Use Fermenta Lock for:

Pickles (all kinds)
Sauer Kraut
Milk Kefir
Bean Paste/Hummus
Sourdough Starter (if started with culture or yeast)
Anything which needs gas release without a lot of air circulation.

Customer Comments

“Living down in Guatemala, we have quite a lot of dampness in our houses and mold is an ongoing battle. After a long dose of antibiotics due to a parasite, I absolutely required probiotics to get my gut back in order and I know homemade sauerkraut has more probiotic content than anything else I could find here. I wasn’t able to make my beloved sauerkraut or even Kombucha in my kitchen because mold would start growing immediately on the top. Your Fermenta Locks have literally been a lifesaver for me! No more mold, and PERFECT Kraut EVERY time!!! Thank you for creating such a wonderful product!!!”

A. Kratzert

“Oh how I wish I had found you first!! Too many experts and too many bucks later I discovered your “Lock” and the sheer elegance and simplicity of your system.Thank you for your help and affordability, it makes healthy food attainable.”


“I came back to order more FermentaCaps. A wonderful innovation. I have not lost a single batch of sauerkraut since I started using the original Fermenta Locks.”


“Please continue your good work on producing such a great product. I’ve tried lots of other kinds of airlocks- the 3 piece water lock, pickle pipes, fermilid, boss pickler, and I think yours is the best design and quality. I’d like to order another 100 of them right now, but I’ll have to wait a bit. I’ve had lifelong health challenges. I’m 38 and about 20 years ago my health was so bad I didn’t feel like living most of the time. Now my health is the best it’s ever been and it wouldn’t be possible without fermented vegetables, they have made a huge improvement in my health.”


(Last names omitted to protect customer privacy.)