Each individual’s needs are very different. A family of 6 would need more fermentation jars than a single person living alone. At a minimum, starting with a 1.5 L and a 3 L jar. To decide on what jar sizes may meet your specific needs consider the following factors.
Storage space. Most ferments require 7-10 days at room-temperature (primary ferment), then 1-13 weeks in cold storage (secondary ferment) to complete all four phases of fermentation (many fermentation resources recommend much shorter times that do not work though all bacterial products). Consider your options for cold storage in an area <12 degrees: Do you have a root cellar, garage, second-fridge, or are you limited to your family’s main fridge to store your ferments. If you are limited to using your main, family fridge, then consider, how many jars could you store in the fridge while leaving space for food? The large airlock adds 4-inches to the height of each jar. For example, a 3 L jar with the large airlock inserted stands 14 inches tall. If you insert the mini airlock during cold storage, a 3 L jar becomes only 13.5 inches (a mini airlock adds 2.5 inches to the jar height).
Preserving the harvest. Are you interested in fermenting vegetables that are in-season, are freshest, and have the most nutrients? What size would be reasonable to meet your needs over the winter if you preserved the summer and autumn harvest? Often the larger jars, 2 to 5 L, are best for preserving the harvest compared to doing smaller batches throughout the year with out-of-season vegetables bought from the grocery store.
Demand vs. fermentation time. How many people will be eating the ferments you make? A family of 6 versus a family of 2 will finish ferments at vastly different rates. A family of four, who each each ~1/2 cup of sauerkraut daily would finish a 3L jar in 2 weeks. It takes 2-3 months for sauerkraut to ferment completely. While waiting for sauerkraut to finish fermenting, consider making a quicker ferment, such as beet kvass (17 days), brine-pickled vegetables (1 month), carrot juice (21 days), potatoes (5 days), etc, to fill in the gap. Planning a fermentation rotation is helpful. This would require at least 2 jars.
Examples. The bundles in the store were thoughtfully assembled based on what has served the needs of people since 2016, when I began selling jars. I’ve also considered the ferments I commonly recommend to people for various health purposes.
5 or 3 L jar for beet kvass
3 L or 5 L jar for sauerkraut
2, 3, or 5 L jars for preserving summer vegetables
1.5, 2, or 3 L for carrot juice
1.5 L jar for brined onions
1.5, 2, or 3 L jar for brine-pickled vegetables
0.5 to 1 L jar for brined turmeric, garlic cloves, relishes, mayo, other condiments
1 L for dosa
1 L for fermented porridge
No, not necessarily. “Lacto,” in the term, lacto-fermentation, simply refers to lactic acid bacteria, the main microbe responsible for transforming food into fermented products with a characteristic sour tanginess that so many people love. Lacto-fermentation is not limited to vegetable ferments, however. Lactic acid bacteria are also involved in dairy, grain, and bean ferments, as well as vinegar. For example, dairy ferments, such as yogurt, kefir, buttermilk, and sour cream, are produced through the conversion of lactose to lactic acid and carbon dioxide by lactic acid bacteria. In vegetable ferments, lactic acid bacteria utilize natural starches in vegetables to produce lactic acid and carbon dioxide.
Fermented vegetables are indeed high in sodium. In excess, sodium increase blood pressure and damages blood vessels. Weighing the exact amount of salt for a specific brine concentration will ensure the least amount of salt is used for safe fermentation.
One teaspoon of salt has 2400mg of sodium. The recommended amount of sodium for an adult 19-50 years old is 1500mg. The daily upper limit is 2300mg. Some people, such as athletes or outdoor workers, may require more than this; however, the vast majority of North Americans exceed the adequate amount through eating in restaurants and eating packaged food. Moderate salt used in home cooked meals as a flavour enhancer or at the table contribute less to the overall daily sodium intake than restaurant and packaged food.
For health-conscious eaters who make fermented vegetables a regular part of their diet, sodium intake can accumulate easily. Still, sodium aside, the nutritional and probiotic benefit of fermented foods is astounding. Avoiding fermented vegetables due to its high sodium content is unnecessary even for people with hypertension. Consuming a moderate amount of a few ferments, daily, is a better approach than eliminating fermented foods due to sodium. Try having one ounce of beet kvass, 1/4 cup of sauerkraut, and a 1/4 cup of brine-pickled vegetables, daily, for gut health and disease prevention.
The only scenario for complete restriction of fermented vegetables is when a therapeutic low-sodium diet is ordered by a doctor to manage ascites or fluid overload. Still, 1 ounce of beet kvass at 0.5% brine may be approved by the physician after weighing the pros (microbes) and cons (minimal sodium).
Microbes, of course! Canning eliminates microbes and deactivates enzymes with heat; fermentation encourages the growth of specific microbes while discouraging others. These preservation methods also differ in how acidity (drop in pH) is reached. Canning lowers pH by adding vinegar, lacto-fermenting by organic acids, primarily lactic acid, produced by lactic acid bacteria. Fermentation relies of microbes and the resulting by-products to preserve vegetables. Some fermented foods have vinegar added to adjust flavour, although it is not necessary to ensure safety.
Fermentation is a non-sterile process that depends on microorganisms to transform vegetables in a controlled environment. Salt, temperature, pH, and an anaerobic environment are hurdles to harmful microorganisms while selectively promoting the growth of lactic acid bacteria, the players of fermentation.
Instead, prepare the jars and equipment by washing with non-antibacterial dish soap and hot water, then rinsing. Lightly rinsing with distilled water or filtered water rather than tap water is a good habit, but not essential. Finish by drying the jars and equipment with a clean cloth.
Optimally, vegetables and salt are weighed to create a specific brine based the brine concentration recommended in your recipe. Vegetables come in all shapes and sizes. One head of cabbage, for example, may range from the size of a softball to a basketball or larger. Salt can be kept to a minimum when you know the exact weight of vegetables.
If you do not have a weigh scale at home, ask your neighbours to borrow theirs. Alternatively, weigh your vegetables at the grocery store. Account for the parts of your vegetable that will be discarded, e.g external cabbage leaves, cabbage core, ends of vegetables.
Keep in mind one level teaspoon of Redmond Real Salt equals 4 grams, one level tablespoon is 17 grams. This changes with the type of salt used – coarse vs. fine, wet vs. dry, and refined vs. unrefined – because volume measurements don’t account for air pockets or density. Weighing salt is more accurate than measuring. That said, some famous fermenters (e.g. Sandor Katz) judge the amount of salt needed by taste and by brine formed at the bottom of the bowl. Get into the habit of sampling your salted shredded vegetables before packing to associate brine concentration with taste, texture, and brine.
Temperature is really important for yielding fermented vegetables with a desirable acidity and flavour. The optimal temperature for the first phase of vegetable fermentation – the first 7-10 days – is 18-21°C. Ensure that the temperature is kept stable during this period, as much as possible. Although many people keep their fermentation jars in the kitchen, temperatures often vary considerably throughout the day depending on heat generated from cooking and applicances.
After this initial phase, ferments should be transferred to a cooler temperature to reduce fermentation rate. Ideally this is <10°C in a root cellar or fridge (keep the airlock inserted through the lid). Safe products are still possible between 10-18°C, yet the product may have inferior texture and taste.
Keep your fermentation jar away from direct sunlight, and in an area where you can keep an eye on the activity. UV rays kill lactic acid bacteria, the key players in fermentation. Wrap a dark, thickly woven towel around each jar to reduce UV’s from penetrating through the glass. Avoid covering the airlock.
If you put your jar in a closet, ensure the proper temperature range is upheld. Also, have a reminder note in case you forget about it. The airlock system takes the babysitting out of fermentation; however, it still requires attention in the event of brine overflow in the first week.
If a closet or north-facing room or dark storage area is too cool for your ferment, consider creating a dark environment instantly by putting your jar in a cardboard box. Don’t forget a catch plate for brine inside the box. Cut a “V” in any box flaps that obstruct closure. Prop up your jar so that the bottom of the airlock barrel is flush with the top of the box. Don’t let anything push the airlock sideways or this may affect the seal.
Thawing vegetables softens the texture. If you ferment vegetables that are limp to start with, your product will be limp and soft; that is, don’t expect crunchy sauerkraut if you start with frozen cabbage.
Freezing also reduces the microbial count, which may affect lactic acid bacteria out competing spoilage microbes in the first 72 hours. It is best for successful results to use fresh, preferably organic and local, produce.
Cooking vegetables requires heat. Heat kills microbes; thus, fermenting previously cooked vegetables is not a common practice. However, there are some cooked vegetables, such as roasted potatoes, that have been fermented successfully.
No, cultures or starters, such as whey starters for vegetable ferments are not needed for home-scale fermentation. ByDesign Nutrition & Health supports traditional wild fermentation, meaning fermentation that uses microorganisms native to foods being fermented. Microbes exist on the outside and inside of plants and other foods. Given the right conditions, microorganism follow a particular sequence of growth as fermentation progresses, yielding a safe and completed product without a starter culture. In contrast, culturing introduces isolated organisms to initiate fermentation, lending to reproducible results for commercial sale.
Commercial yogurts use pasteurized milk, which is heated to destroy native microbes. Specific microbial cultures are reintroduced for milk to ferment into yogurt. Some yogurt companies have patents on yogurt cultures to brand a specific flavour or health appeal. For example, Activia has a patent on Bifidobacterium lactic CNCM 1-2494 (on the label it reads B.L. RegularisTM).[
Submerging vegetables – shredded or whole – under a brine is important in fermentation. The brine level in brine-pickled ferments should not fluctuate greatly when transferred from room temperature to cold storage. The brine level in shredded vegetables, such as sauerkraut, will, however, fluctuate with this temperature shift. At times, the brine level may fall below the vegetables.
If this occurs, open the jar lid and press the shreds with a wooden spoon or cabbage tamper to reinstate a tightly packed ferment. Shredded vegetables expand during at room temperature as bacteria produce carbon dioxide. As this gas surfaces, pockets form between the shreds, causing the ferment to expand. These pockets contract in cold storage with reduced bacterial activity. Brine from the headspace is drawn into the shreds to fill the pockets. By tampering the shreds, you force the pockets out, pushing the brine to the top.
If the brine level still remains below the vegetables, pour 1/4 cup of 2.5% brine over the ferment. You can also pour brine, which was drawn into the airlock, back into the ferment. Restrain from disrupting the ferment any further if the brine level still seems low. Provided you have not lost too much brine in the first phase of fermentation, your kraut should not be dry.T he top inch of shredded vegetables may turn grey over long storage periods. Simply discard that layer once you are ready to eat your ferment. The layer beneath that is fine to eat
Over long storage periods, very small amounts of brine will evaporate from the airlock or be pulled into the ferment. I’m not entirely sure. Remember to keep the airlock topped with water to the fill line.
Brine is drawn into the airlock if the jar is packed too full. This is more of an issue with shredded fermented, i.e self-brining. For most shredded ferments, a rough guideline is to pack vegetables 1-inch below the shoulder of the jar, leaving the remainder as headspace. The ferment will expand as bacterial activity increases.
Sometimes packing isn’t the issue, but rather, using vegetables that brine well. Some varieties of cabbage, for example, are poor-brining (e.g. winter cabbage) while other varieties are quick briners. It is easier to loose brine with quick-brining cabbage. It will be pushed out of the jar through the airlock.
Some vegetables contain more sugar depending on when these are harvested; other vegetables contain more sugar than other vegetables in general. More available starch, such as in carrots, beets, and other root vegetables will make for active ferments. Active ferments usually expand more, potentially driving more brine into the headspace
With experience comes better awareness of how full to fill jars, depending on the vegetable used and the time of the year, thus temperature.
Wait until your ferment is ready to transfer to cold storage before cleaning the airlock. If you clean it out while the ferment is still active, it may become dirty again.
It’s easiest to have a second cleaned and filled airlock ready to replace the dirty one. Do a quick swap to minimize exposure to oxygen. Alternatively, remove the dirty airlock, insert the plug, clean and refill the dirty airlock with clean water, then remove the plug and insert a fresh airlock. Now your ferment is ready for cold storage. Opening the lid is not necessary for this process.
The liquid phase of ferments is actually the richest source of nutrients, phytochemical and microbes. Losing brine makes for drier ferments, especially shredded vegetables like sauerkraut. Even though oxygen is displaced by CO2 inside the Airlock Fermenter, it is still good practice to ensure vegetables are submerged under brine. Brine should always cover brine-pickled vegetables. Brine may not cover topper leaves in sauerkraut, but it should cover the shreds.
Botulism spores grow at a pH of 4.6 or above. All the resources I have read recommend waiting to eat the ferments after pH has dropped below 4.6 below consuming.
Testing the acidity of your ferments may give you peace of mind, but it is not 100% necessary. The time guideline included with my recipes are sufficient to produce this acidity drop. Initially, testing pH with test strips may help you understand how changing variable in fermentation like the vegetable, temperature, or brine concentration affects acid development. Of course, if your ferment smells off, has visible mould or yeast, a slimy texture, or an off-colour than expected, error on the side of caution and toss the batch.
Testing by the Agri-Food Laboratories at the University of Alberta showed my Leek Pepper Sauerkraut had a pH of 3.89 and my Tarragon Beet Kvass had a pH of 3.56. If you follow the guidelines outlined in my recipes, fermentation is extremely safe -safer than eating raw vegetables according to some microbiologists.
Buy salt that is unrefined, non-iodinized, and does not have any anti-caking agents or chemicals added. Iodine in fortified salts can darken vegetables and is an anti-microbial agent – something to avoid when trying to encourage specific types of microbes for fermentation. The trace amount of iodine inherent in sea salt is okay. Anti-caking agents turn brine very cloudy and form white sediment. A dusting on brine-pickled vegetables, especially, cucumbers is a normal by product of lactic acid bacteria, yet anti-caking agents results in cloudy brine.
Ideally, salt used in fermentation should have a wide range of minerals and trace minerals. This type of salt often comes in dry or wet forms, indicating its origin from land or from sea, respectively. Redmond Real Salt and Himalayan Crystal Salt are dry salts; whereas, Celtic Sea Salt and French Grey Salt are wet salts. Both give the end product different tastes. Wet salts can harbour more potential for mould growth, so my preference is dry salts especially in open fermentation systems. All ByDesign fermentation workshops use Redmond Real Salt.
At all costs, avoid using commercial pickling salt because it is usually iodized, coarse ground, and has a different ratio of sodium chloride to minerals.
Insufficient salt may result in low brine formation in shredded vegetables and end products that are mushy/limp. Early stages of fermentation may progress too quickly, causing off flavours.
Excess salt will undoubtedly make the ferment difficult to stomach! Brine concentration greater than 2.2% for sauerkraut starts to reduce lactic acid bacteria. These microbes are salt-tolerant though only to a point. Some people rinse ferments, including sauerkraut, before eating, yet rinsing excess salt also sends probiotics down the drain. In addition to saltiness, excess salt lends to more sour ferments. Ferments made in the summer usually require more salt to temper the high fermentation rate due to higher temperatures. For sauerkraut, stay between 1.8-2.2% brine concentration. Depending on the vegetable, brine-picking brine concentrations range from 0.5% to 10%. Consult your recipe.