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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.

The term “fermented foods” applies to many different kinds of foods, which can be loosely classed in several different categories.

This can help you know which type of fermentation process works best, and what kind of environment is appropriate for the food you want to ferment.

Fermentation does two things: It encourages the growth of certain microbes – bacteria or yeasts (that means FUNGUS, or even MOLD – not all mold is harmful). Those microbes then CHANGE the food – imparting a different flavor, incorporating air bubbles, adding alcohol, extending shelf life, or other changes that people want to impart to their food.

So, we have foods that do really well in an open container, some that do well in open or closed container (they aren’t picky as long as conditions inside the ferment are right), and some that are easier to ferment in an airlock system (because they do best in a closed container, but they release a lot of gas, and an airlock system vents more easily). NONE of them require an airtight environment.

Some of the basic classes of fermented foods include:

  • Brine pickled foods – this includes pickled vegetables of all kinds, pickled salsa, and sauer kraut. These foods either use a salt and water brine to submerge the food, or by adding salt to the food, they create their own salt brine to cover the food. These are some of the easiest foods to ferment. They work well in either type of fermenting system as long as you keep the food under the brine.
  • More solid salted fermented foods – bean paste, hummus, mustard, ketchup, mayo, and other foods which are fermented but do not have a brine on them. These do best in an enclosed system, though you need to leave plenty of headspace, they can expand quite a bit! Many people do these successfully in a mason jar, by venting the lid periodically to keep gasses from building up.
  • Cultured Fermented Dairy – Kefir and yogurt, sour cream, and other milk cultures which are cultured using a specific bacteria or bacteria and yeast starter, and which are grown to encourage the growth of those specific microbes in the milk. These can work well in either type of system, though a closed (but not airtight) system is traditional. Kefir will gas quite a bit.
  • Sourdough – Either wild or cultured sourdough starter. This can go either way also, and partly depends upon the stage the starter is in. To begin with, some starters work best in an open fermenting environment. If reviving a dried starter given to you by someone else though, you may wish to do it in a closed airlock environment, to discourage outside contamination (this is actually NOT a huge issue from the air unless you live in a very moldy environment, most outside contamination comes from ingredients, or improperly cleaned dishes, not from the air).
  • Alcoholic Beverages – Modern brewing is done with an airlock – Traditionally done in open vats, or in a cask with a hole at the top which let out the gasses and much of the foam as the brew expanded. After the initial fermentation, it is sealed up in containers for long term aging, or in the case of ale, used right away. The goal here is to concentrate the alcohol and keep out airborne microbes that would cause it to turn to vinegar. Alcohol is usually cultured with specific microbial cultures to produce a more predictable flavor, but was traditionally done without that. There is NO direct comparison in needs between alcoholic beverages and pickled vegetables, because one has a high amount of natural sugars, and the other is fermented in a salt brine. Those two internal environments are completely different. We do not provide information on creating alcoholic beverages nor do we encourage their manufacture.
  • Water Kefir – This stuff will brew open or closed. If you want a low alcohol concentration, drain off the grains, and re-ferment the water for several days, in an open or loosely lidded container. This diminishes the alcohol content and gives it a vinegary flavor and smell. If you keep it in a closed container, it WILL become alcoholic. “Tests” which purport to show otherwise were improperly conducted, invalidating the results. It becomes most alcoholic when combined with fruit juice (you just made wine, folks!).
  • Kombucha, and Vinegar – both of these ferment best in an open fermenting container, until established. Vinegar, once it is finished fermenting, is stored in an airtight container. Kombucha is fermented in an open container until the Scoby is established, after which it can be fermented in an airlock. Kombucha is another thing which we do not ferment ourselves, nor do we provide further information on doing so (it is mentioned here because of the number of requests we get regarding which type of cap to use).

The type of environment a fermented food requires depends upon the needs of the food during fermentation, and upon the end goal.

Once you can do one food from a fermenting group, you can easily do another from the same group. Even between all of the groups, a similar set of skills and conditions are required for the majority of the tasks involved, so it is not difficult to learn to make pickles if you have made kefir, etc.

The whole argument over whether you have to have an airlock system to properly ferment foods or not is pretty silly really. Some things REQUIRE open air, some do better in a closed system, but none of them require an airlock. It is just a matter of convenience for those things which do better in a closed system but which gas a lot during the fermentation process. It helps to not have to keep venting the jar.

Frankly folks, we’d love to sell you our airlock cap. But we’d much rather give you the facts and retain our integrity than to leave out half of the truth in an attempt to persuade you to buy our product. If you want convenience, good tools can help make the process easier and a bit more predictable. But if you just need to get good food onto your table, just DO it, and don’t feel guilty because someone is trying to persuade you that you have to spend a boodle to do it right! You don’t. Just follow the longstanding rules that humanity has practiced for thousands of years, and you’ll be able to turn out healthy and invigorating foods that you and your family can enjoy for months.

Happy pickling!

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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This website is only equipped to handle orders from US customers (International shipping must be calculated for each order). International Orders are now accepted BY EMAIL from UK, AU, CA, and shipped USPS (other countries will be considered if requested). Please email a list of the items you wish to order, using our Contact page, and we will give you a shipping quote, and then invoice you from PayPal for the total.
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.)