Saturday, April 27, 2013

Sauerkraut

Homemade sauerkraut is easy to make and delicious. With little in common with most commercial versions, homemade sauerkraut is bursting with tangy flavor, healthful nutrients, and friendly probiotics.

Introduction

Today's post goes over the process of making sauerkraut. This is a detailed post with lots of background. Don’t let the amount of information intimidate you; making sauerkraut is very easy and does not require a lot of precision. It does require an investment in time, however, but keep in mind that one well-planned afternoon of sauerkraut-making will provide you with delicious homemade sauerkraut for an entire season or longer.

Sauerkraut is a traditional food that is chock full of essential nutrients, healthful enzymes, and beneficial probiotics. It was first introduced to America by Pennsylvania Dutch settlers but is a familiar food to many ethnic groups from Central and Eastern Europe as well as Asia.

Homemade sauerkraut is not like commercial sauerkraut in that commercial sauerkraut is generally pasteurized and then packaged in a brine of extremely salty water.  The best way to prepare commercial sauerkraut is to rinse it well under running water while squeezing out the brine. This gets rid of excess salt and mutes the unpleasant taste of the commercial brine, which in addition to salt often has vinegar along with less pronounceable additives. This type of sauerkraut is best served cooked. Pasteurized commercial sauerkraut has none of the beneficial probiotics or enzymes of homemade sauerkraut but it still has plentiful nutrients and is a healthful food when properly rinsed and prepared.

Homemade sauerkraut, on the other hand, develops a delicious and healthful brine that should never be washed away. Also, while it can be served cooked (in which case the flavor resembles commercial sauerkraut), it is both better tasting and more healthful when served raw. As an alternative to the traditional method of cooking, which often requires hours of cooking time, homemade sauerkraut can be quickly steamed. This compromise preserves much (but not all) of the healthful probiotics and enzymes while still allowing the sauerkraut to be served heated.

Overview of fermentation

Fermentation by lactobacilli is introduced naturally, as these air-borne bacteria culture on raw cabbage leaves where they grow. Yeasts also are present, and may yield soft sauerkraut of poor flavor when the fermentation temperature is too high or if there is too much oxygen exposure.

The process has three phases, sometimes referred to collectively as population dynamics. In the first phase, anaerobic bacteria such as Klebsiella and Enterobacter lead the fermentation, and begin producing an acidic environment that favors later bacteria. The second phase starts as the acid levels become too high for many bacteria, and Leuconostoc mesenteroides and other Leuconostoc spp. take dominance. By this time, any harmful bacteria that may have been present on the raw cabbage will have died off. In the third phase, various Lactobacillus species, including L. brevis and L. plantarum, ferment any remaining sugars, further lowering the pH while developing the flavor of the kraut.

Most commercially available sauerkrauts are pasteurized but this step is not necessary with homemade versions. Fermentation is very safe and there have been no known fatalities from eating homemade sauerkraut. Indeed, the friendly bacteria that are so beneficial to our digestion are downright unfriendly to germs that cause food sickness. Properly cured sauerkraut is sufficiently acidic to prevent a favorable environment for the growth of Clostridium botulinum, the toxins of which cause botulism. Fully cured sauerkraut keeps for several months in an airtight container stored at 15 °C (60 °F) or below. Neither refrigeration nor pasteurization is required, although these treatments prolong storage life.

Pickling versus fermentation

Pickling is the processing of preserving vegetables in an acidic brine. Traditionally, this was synonymous with fermentation but lately vegetables pickled in vinegar have become quite popular. Pickling in vinegar does not involve fermentation (other than the fact that vinegar is itself a product of fermentation) so while all fermented vegetables are pickles, not all pickles are fermented.

Basic Sauerkraut Recipe

This basic sauerkraut recipe assumes that you are already familiar with the techniques required for fermenting vegetables. Use it as a handy reference after you've read this blog.

Ingredients

  • 1 head Cabbage
  • 1 – 3 TB spoons Salt
  • 1 – 3 TB spoons Caraway seeds

Procedure

Wash cabbage. Remove and reserve outer leaves. Shred cabbage using knife or cabbage shredder and layer into a large container, sprinkling salt and caraway into the mixture until all cabbage has been shredded and seasoned with salt and caraway.

Massage cabbage by wringing handfuls with clean hands. Give each handful a one-second squeeze as you simultaneously twist. Continue wringing cabbage for about 10 minutes, ensuring that all the cabbage is being massaged equally.

Allow the cabbage to sit for two hours. If possible, pressurize the cabbage by weighing it down under a plate with weights atop or with some other ingenious system. (Sealed Ziploc bags filled with brine are a popular alternative.)

Begin filling your fermentation vessel with cabbage, tamping it down firmly as you go. When vessel is 4/5 full or all cabbage is in the vessel then cover with reserved outer leaves, weigh down to push cabbage below liquid, and close your fermentation vessel.

Remember to leave the vessel loosely covered so gases can escape, or else remember to burb the vessel once or twice daily during the next week and several times a week after the first week.

Store at room temperature for a week then move to a cool basement or similar location. (If your vessel has a water seal then it's self-burping, as you will realize within the first week.)

Begin eating after three weeks. Sauerkraut can be refrigerated after three weeks but does not require it if stored in a cool location.

Materials

Gathering the materials to make sauerkraut requires advance planning and is the most difficult part of the process but is well worth it. Fortunately you generally only have to do this once (not counting the occasional equipment upgrade).

Fermentation vessel

You will need a container to hold your kraut while it ferments. It is best to use ceramic or glass as metal might react with the brine and plastic might leach carcinogens into the brine. (Stainless steel is an exception; it is safe to use in ferments and is often used in commercial operations.) I currently use a special fermentation crock; these are available online and come in various sizes with the smaller ones being quite affordable.  The larger ones can be pricey, especially the German-made Harsch pots. A good pot will have a water seal so that gases can safely escape from the pot while air, along with its unwelcome bacteria and spores, will be kept out. Even though some mold and yeast spores will inevitably make it into the vessel while you are packing it with cabbage, the gases from the fermenting vegetables will force the air out of the vessel through the water seal, creating an oxygen-free system that is inhospitable to molds and yeasts.

Most crocks also come with weights designed to fit snugly inside the crock to push the vegetables down beneath the surface level of the brine. This is important since any vegetables floating on the surface will attract mold growth. The salt in the brine will prevent mold growth on submerged vegetables.

But for my first batches I just used an assortment of ½ gallon mason jars (see Figure 2). These jars are readily available online and in stores (hardware stores and supermarkets seem to have them, as does WalMart), especially during canning season. The first time I made sauerkraut I used two heads of cabbage, a bunch of carrots, and three ½ gallon jars. I would recommend that you start with just one head of cabbage and one jar, with perhaps a smaller 1 quart jar in case you need extra room. Mason jars do not have the water seal or weights so you will need to account for that. I used small shot glasses that fit inside the jars and, when pressed upon by the lid, push the vegetables down below the surface of the liquid. I then left the lid slightly loose (a quarter turn or so counterclockwise from snug) to allow gas to escape. There are stories on the internet of jars exploding owing to jars being too tightly closed so don’t use this is an opportunity to exhibit your awesome strength! Special lids are available inexpensively online that will provide an airlock conceptually similar to the water seals on the fermentation crocks but designed to work with jars.

If you are using the type of jar that clamps shut (known as a Fido jar) then this is a great jar to use but you will have to burp it every day (by gently releasing the lock then closing it again) during the first week and every few days or so thereafter. If you overfill this type of jar then brine may be released when burping. (And by "released" I mean "sprayed all over".)

In addition to mason jars and Fido jars, special jars are available on line from Pickl-It that have airlocks built into the lids. These jars are more expensive then plain mason jars but vastly cheaper then the imported crocks with the water seals. Like the water-sealed crocks, the Pickl-It jars create an anaerobic environment for your ferments. Mold and yeasts cannot grow in these jars because oxygen is forced out during the first week of vigorous fermentation and never allowed back in. Like the water-sealed crocks, the Pickl-It jars' ecology is compromised as soon as you break the seal, but, unlike the heftier crocks, you can swap the airlock lid on the Pickl-It jars with a regular and just stash it in the refrigerator.

For your first attempt, and again whenever experimenting with a new recipe or technique, I would recommend a mason jar with a wide-mouth lid, unless you happen to have a crock of some sort laying about, or a Fido jar. Even so, you will want to have mason jars on hand (or some of the less expensive, lidless American-made crocks) for purposes of experimentation with new ferments. The water-sealed crocks are excellent for larger batches but not suitable for experimentation due to the massive quantities they are capable of producing.

The more expensive fermentation vessels add value to your ferments by removing risk from the process. Risks are introduced when the substrate (cabbage in this case) is exposed to oxygen, when the Ph is too high to prevent harmful bacteria from growing, or when salinity is too low to prevent harmful bacteria from growing. Note that the vessels tend to differ only in how they deal with the oxygen problem. Yeasts and molds cannot grow without oxygen; the salinity and Ph affect only the liquid so molds and yeasts are excluded from everything below the surface of the brine regardless of how much money you've spent on your fermentation vessel. For centuries, people used crocks without water seals and just manually removed molds as needed. Nobody ever died from this.

Additional risks that you should consider arise from exposing your acidic brine to plastic for an extended period of time. Many people worry that harmful chemicals can leach from plastic into the sauerkraut over time and so prefer to use glass or ceramics, which are nonreactive. For this same reason, many people avoid the use of brine-filled plastic bags as weights.

Stainless steal is also non-reactive, unlike other metals which react with the acidic brine, but home fermenters do not seem to favor stainless steal vessels. They are used widely in commercial operations, however, because it is easier and cheaper to achieve greater scale with stainless steal. In previous eras (and possibly still today in some places) wooden barrels were also used to ferment cabbage and other vegetables.

A final consideration in choosing a vessel is the size. As alluded to above, your initial ferments should not be overly ambitious. It's best to start with a single head of cabbage, in which case most of the expensive imported crocks are overkill. Besides, you might find that you don't like making sauerkraut or (gasp!) don't care for the flavor. After you've gained some experience you may decide you want to upgrade. (My decision came when I had my first taste of homemade red sauerkraut.) Sauerkraut needs to be eaten within a few weeks after reaching peak flavor unless it's stored in a cool location. This means that if your vessel is large, you will need a basement or root cellar that's 60°F (15.5°C) or less, or you will have to offload your matured sauerkraut into jars and place them in a refrigerator. I use two water sealed crocks; one is 15 liters and the other is 10 liters. I also have an assortment of mason jars that I use for smaller batches, which are usually experimental in nature.

Weights

Fermentation occurs when the vegetables are submerged in the brine. Unsubmerged vegetables will not ferment; however they may attract undesirable molds. These molds are not harmful but they have an unpleasant taste and are best avoided. Weights are traditionally used to keep the vegetables below the surface of the brining liquid. Most fermentation crocks come with weights. When using a mason jar, you will have to develop your own solution. I use a small shot glass (or two) and let the lid to the Mason jar add pressure to force the shot glasses down against the vegetables, keeping them submerged. Other people use clean rocks or even plastic bags filled with brining solution (so that if they leak they won’t spoil your sauerkraut). If using plastic bags filled with brine then you won't need a lid as the bags will also act as a seal.

Work tray or container

After you chop your cabbage you will need to let it rest while it releases its juices. Some people put the chopped cabbage directly into the fermentation vessel but I prefer to allow the cabbage to rest in a large rectangular plastic container (see Figure 4) for a couple of hours. I don’t worry about chemicals leaching into the sauerkraut so much here because it is used for a couple of hours versus the weeks or possibly months in the fermentation vessel. I trimmed the lid on my container so that it fits completely inside the container. This allows me to place weights on the cabbage as it rests to force out the juices. I set the cut lid atop the cabbage and then stack weights on top of that. (I use food cans as weights, the heavier the better.) This however is probably not necessary as you will be forcing the juices out soon enough. Other folks use food-grade plastic buckets or tubs. Use whatever you have or can scrounge.

Tool for slicing the sauerkraut

My first batch of sauerkraut came out great using just a large knife to shred the cabbage. I’ve since purchased a sauerkraut slicer as shown in Figure 6 but if that one were to break or wear out I will probably not replace it. It saves a bit of time but can be hazardous. I once sliced into a fingernail which means I was approximately a hair away from losing some finger. (The nail did not completely detach so it luckily was never part of my sauerkraut!) Use caution when using a cabbage shredder. As one wedge of cabbage gets low, use another wedge to apply pressure rather than risking your fingers. And use a knife to handle the last bits of cabbage.

Tamper

The tamper is for tamping the vegetables tightly into the fermentation vessel. I use a small French rolling pin as that’s what I had and it works really well. Other people have used two-by-fours, broom handles, potato mashers, or even wooden baseball bats. In Europe, people use their feet (or their kids'). Use whatever is handy but try to avoid metal unless you are certain that it's stainless steal, and make sure it’s clean.

Figure 1. This is a Polish-made ceramic fermentation crock. The lid rests in a trench which should be kept full of water to create a seal. A notch in the lid allows gases to force their way through the water and out but the water in the trench prevents air from coming in the same way. This prevents spoilage and insect infestations during fermentation but does result in occasional audible gurgling and bubbling, especially during the first week of fermentation.

Figure 2. Red cabbage sauerkraut with carrots fermenting in mason jars. Note that each jar rests in a dish to catch overflowing brine. (This might not have been necessary if I hadn’t overfilled the jars!)

Figure 3. In this Mason jar, a shot glass is pushing down on the cabbage, creating a layer of liquid between the cabbage and the air surface. Notice that the shot glass is also exerting some upwards pressure on the jar lid. Unfortunately, the richly colored brine hides the shot glass from view. (This jar is too full; ideally there would be at least an inch of air in the closed jar to accommodate the expansion that occurs during fermentation.)

Figure 4. A container like the one above is useful for massaging or kneading your cabbage chopped cabbage to rest and release its juices. Food-grade plastic buckets and tubs also work well.

Figure 5. A French-style rolling pin makes a great tamper. It's also useful for chasing off unwanted guests.

Figure 6. This slicer is designed specifically for slicing cabbage for sauerkraut. It produces slightly thicker shreds than commercially available sauerkraut. Mandolins are similar and also work well.

Ingredients

Once you find the materials then it’s time to gather your ingredients. Most of the ingredients can be gathered ahead of time (or will already be in your pantry) but the vegetables should be as fresh as possible to ensure the highest levels of juice.

Cabbage

Most recipes call for regular green cabbage (also known as white cabbage due to the fact that the inner leaves are white) but I’ve had the best luck with red cabbage (Brassica oleracea var. capitata f. rubra), which makes delicious sauerkraut with a rich burgundy color, full of anti-oxidants as well as vitamins, probiotics, and enzymes. There are a number of other cabbage types and subtypes. European cabbages are all cultivars of Brassica oleracea. Interestingly, broccoli, kale, cauliflower, collard greens, and Brussels sprouts are also all cultivars of this single plant species. They are like the dogs the plant world; so different yet fundamentally the same DNA.

Asian cabbages tend to be members of a different but closely related species, Brassica rapa. Nappa cabbage, a type of Chinese cabbage (Brassica rapa var. pekinensis), is famously juicy. Bok choy, another type of Chinese cabbage (Brassica rap var. chinensis) is crazy high in vitamin A and has about as much calcium as milk.

When selecting a cabbage for fermenting, keep these guidelines in mind:

  1. All types of cabbage make delicious sauerkraut.
  2. The best sauerkraut comes from fresh cabbage; select the freshest variety that you can get.
  3. There is no rule that says you may only use one type of cabbage in a given batch. I hardly ever do.
  4. The best cabbages for krauting are fall cabbages. Plan on spending some time in early November salting away a goodly batch.
  5. Fermentation is a forgiving process. If you aren't sure if those lovely cabbages are fresh enough for kraut then don't worry; they probably are, and if they aren't then you can always add extra brine to fix them. Problem solved.

The amount of cabbage you need depends primarily on the size of your vessel and also on the amount of sauerkraut you want to make. One head of cabbage is a good amount for your first attempt. If possible, use organic cabbage as other cabbage is sometimes sprayed with chemicals that inhibit spoilage (and thus fermentation).

Salt

Himalayan salt is the favorite on the internet while pickling salt is the more traditional salt variety used in making sauerkraut and other fermented vegetables. I use Himalayan salt when I have it; otherwise I just use kosher salt or whatever other kind of salt I have on hand. Any salt will work, although you may have to adjust amounts slightly because kosher salt is bulkier (i.e. less concentrated) than finely-ground table salts. Iodized salt will cause the brine to become cloudy and so its use is usually discouraged, but if that's all you have available then it will still work. Despite sauerkraut’s reputation for being high in sodium (well earned in the case of commercial sauerkrauts) you only need about one tablespoon of salt per head of cabbage. The precise amount is up to you as the recipe is very flexible. I always taste the brine as I'm making my kraut to assess the level of salt; I like to be able to taste the salt but do not want to be overpowered by it. If you omit salt entirely then you run the risk that your entire batch will spoil. If you use too much then your sauerkraut will be unpleasantly salty. If you plan on storing your sauerkraut for an extended time before eating it (as was the practice traditionally) then you will need to increase the amount of salt, but never to more than 3 tablespoons per head. Some recipes omit the salt entirely but these ferments are more susceptible to failure. 

Caraway seeds

Some people really do not care for caraway and if that describes you or yours then go ahead and omit it. You will need about as much caraway as salt. Do not substitute with more salt but you can substitute with other spices if you’d like.

Brine

Cabbage generally has enough juices that you don’t usually have to add your own brine, but I always have some ready just in case. Besides, the sauerkraut brine is healthful and delicious so it never hurts to make extra. I use one teaspoon of salt to one cup of water and I usually make about a quart (four cups) of brine. If you have filtered water (a simple filter like Brita is sufficient) or spring water then you can make this just as you need it but if you are using tap water then you need to boil the water, salt it, then let it come back down to normal temperature before using it. Both chlorine and hot water will kill the probiotics and halt fermentation so you want to avoid using both. You can make the brine well in advance and keep it in the fridge until needed. Just don’t drink by mistake because it isn’t tasty (yet).

Starter

Many ferments require a starter, and many sauerkraut recipes call for one. Don't be fooled; you do not need a starter to make sauerkraut. In fact, Dutch scientists have determined that use of a starter can have a detrimental affect on the flavor profile of the finished sauerkraut owing to the starter's interference with normal population dynamics.

Some recipes on the internet call for the use of whey as a starter. Whey probably is harmless as a starter but neither does it have a beneficial affect. I suspect that superstition and naivety have led to the belief that you should use whey as a starter for sauerkraut. Whey is a nutritional by-product of milk fermentation and, as such, contains completely different species then those in sauerkraut. It is unlikely that those species will even survive in the salty brine of a new ferment or that they will find cabbage to be a satisfying substitute for milk.

An exception to the "no-starter" rule is for people who, for health reasons, must avoid salt. In these cases, the best course of action may be to buy commercial vegetable lactose fermentation starter from a reliable vendor. In this manner, you can greatly reduce or even entirely eliminate salt, relying on the starter to kick-start your fermentation so that high acidity (low Ph) is achieved more rapidly before unfriendly "malbiotics" have a chance to take hold. Normally, the salinity of the brine provides you with a longer window but without the salt a starter can shorten the window and increase your odds of success without salt.

Other

There is an almost infinite list of other ingredients you can include. I often include bok choy or sliced carrots. I usually also include a couple of grape leaves to ensure crunchiness. See the section on Variations for more ideas.

Figure 7. American-style fermentation pots do not usually come with lids, although wooden lids are often sold separately. Sometimes the lids actually fit inside the vessel, serving as a platform upon which to place the weights. Be careful when using wooden lids in this fashion, especially if the lid is new. Long term exposure to the brine can sometimes cause wood to expand and warp, and your sauerkraut could get trapped beneath a lid that is now firmly wedged in the pot.

Procedure

Now we can make some sauerkraut!

Start by setting up a work area. You will be chopping a head of cabbage so be prepared for little pieces of cabbage to go flying. For me this means covering the island in the kitchen with clean towels and laying newspapers on the floor around the island to catch the bits that go airborne. (Failure to follow this procedure can lead to spousal freak-out. Besides, red cabbage can cause stains.)

Rinse cabbage (and other vegetables if applicable) well. Remove tough outer leaves of the cabbage and reserve. Remove the bottom quarter inch (six or seven centimeters) of the core’s stem and discard. Slice the cabbage in quarters and remove the core. Reserve the core for later.

Slice the cabbage into shreds. Sauerkraut does not need to be sliced and thinly as slaw and my personal preference is for slices about the thickness of two stacked quarters, or perhaps a bit thinner. Other recipes call for the slices to be as thin as a dime, which helps release more liquid but the thicker slices that I produce result in crunchier sauerkraut. There are some traditions that ferment whole cabbages in brine without any slicing at all and it works just fine, so don’t be too concerned if your slices aren’t precisely within the specification.

As you slice, layer the sliced cabbage in the rectangular plastic container. When you’ve sliced about a third of a head of cabbage, sprinkle the shredded leaves with about a teaspoon of salt and a teaspoon of caraway seeds, mixing it together with clean hands. Continue slicing the next third and layer it into the container, covering it with another teaspoon of salt and another teaspoon of caraway and mixing again. Continue doing this until all the cabbage has been shredded and layered with salt and caraway.

With clean hands, mix the shredded cabbage thoroughly. Then begin squeezing the cabbage by grabbing a fistful with both hands and squeezing as if you were wringing out a wet cloth. You don’t have to wring out every drop; just twist, squeeze for one second, and release. Pick up another handful and wring it again. Continue doing this for about ten minutes, being sure to give all the cabbage equal time. Continue mixing the cabbage and incorporating the salt and caraway. If you are including other vegetables such as carrots or bok choy then knead them in with the cabbage the same way.

After the cabbage has been worked sufficiently it will become slick with its own juices and it will feel somewhat relaxed or wilted. Leave rest in the container, optionally covering it with the trimmed lid and placing weights atop. Go and rest for two hours.

Once the two hours have passed you should see a noticeable change in the cabbage. The leaves will have wilted considerably and there should be copious amounts of juice in the container. If you push down on the leaves then puddles should form in the depression.

Start filling your fermentation vessel slowly, tamping the shredded cabbage firmly as you go. Add pieces of the reserved core as you go. These pieces will become delicious pickles whose enjoyment is the special prerogative of the person who made the sauerkraut! Make sure you get all of the juices in the fermentation vessel(s); these juices are critical to the fermentation and will eventually be the tastiest part of the kraut.

Do not fill the container to the top; between 1/3 and 1/5 of the top should be available for the weight and for expansion of the liquid during the fermentation process. Overfilling your jars will definitely result in overflowing brine which is a waste, as the brine is nutritious and delicious once the sauerkraut is ready. If you have a lot of left over cabbage then start a (smaller) vessel, such as a quart mason jar. Place one or two of the reserved outer leaves over the well-packed shredded cabbage. These leaves will help keep the small pieces of cabbage from floating to the top while also acting as a barrier between the sauerkraut and the liquid’s surface in case of mold. (Mold will only form at the surface or on the sides of the vessel above the liquid.) If possible, tuck the sides of the outer leaves in between the sides of the vessel and the shredded cabbage so as to prevent pieces of cabbage from escaping.

Take your weight and place it on top of the cabbage. Press firmly so that liquid completely covers the cabbage. If you are using a fermentation crock then the liquid should cover the weights. If you are using a different vessel then you will have to use your own judgment but keep in mind that the cabbage must be covered with liquid at all times during the fermentation process.

Using a clean damp towel or a moistened paper towel, wipe the interior of the fermentation vessel above the level of the liquid to remove all food particles stuck to the sides. This is important, as mold will grow on any vegetables left unsubmerged, even if they’re little itty bitty teeny weeny tiny itsy bitsy small pieces

Close your fermentation vessel, ensuring that the gases produced during fermentation can escape. Some recipes call for the vessel to remain open but covered with a cloth if the vessel does not have a water seal but I find that a loosely closed mason jar lid allows gas to escape. If your vessel has no lid then use a double or thicker layer of cheesecloth. Use string or a fat rubber band to secure the cloth over the vessel so that insects can’t sneak in.

Place the fermentation in a safe place at room temperature. It’s best to place something under the vessel in case some of the brine bubbles out. (It happens often, so it’s best to just be prepared.) If your vessel has a water seal, now is the time to fill to the brim with water to seal off the interior. For the next week, the initial fermentation will begin. This phase is the most active phase of the fermentation process. After one week, the brine will have become acidic enough for the next population of probiotic bacteria to begin their part of the process. At this point you can move the fermentation vessel into a slightly cooler area, such as a basement or wintertime garage. If you don’t have a location like this, then leave the fermentation vessel where it is. During the first week, expect to hear bubbling and gurgling noises as your vegetables ferment.

During fermentation, you should monitor the progress regularly. If using a vessel with a water seal or other airlock, monitoring simply involves checking the seal to make sure the water has not evaporated out of the seal. You may need to top off the seal with additional water from time to time. You should use tap water for the seal. Do not open the vessel until the sauerkraut is ready or you will compromise the ecology of your ferment and will have to regularly check the interior for mold and yeasts.

If using another type of vessel then you will also have to check for mold. Mold will only grow on the surface of the brine, or along the sides of the vessel above the water line if food particles are stuck to the sides. You should carefully remove mold whenever you see it developing as it can impart an unpleasant taste to your sauerkraut if left to grow unchecked.

If you are using a vessel with a wire clamp over the lid then you will have to burp it periodically, especially during the first week when it will need to be burped once a day or more. Failure to do so in a timely manner will cause the jar to act like a shaken can of carbonated cola once you eventually do try to burp it. This can cause quite a mess and lead to spousal freak-out.

After two to three weeks of fermentation you can begin tasting the sauerkraut. If you started a second smaller vessel then open that first. If you used a large fermentation crock and several heads of cabbage then you will need to offload some into a mason jar and refrigerate the jar. When you’ve finished the jar then refill it from the fermentation crock, but try to avoid opening the fermentation crock too often as each time you break the seal you risk compromising the ecology of the fermentation vessel. Each time you open the vessel (except for the first) you will need to skim off molds and yeasts from the surface of the brine before decanting the sauerkraut.

If you are using a crock with a water seal, you can wait several months before breaking the seal as long as you are diligent about keeping the seal full of water. I personally prefer to transfer my sauerkraut from the water-sealed crock to mason jars after initially breaking the water seal. This is because once the seal is broken, then oxygen will get into the vessel and mold and or yeasts will grow on the surface of the brine as well along the unsubmerged sides of the vessel.

If using mason jars with an airlock, you can just swap the airlock lid for a regular lid and transfer the jar as-is to the refrigerator once you've has a taste and decide the sauerkraut is finished fermenting. If you are using a mason jar or some other type of jar with a regular lid then you can just transfer the whole jar to the refrigerator once fermentation has completed to your satisfaction. I usually remove the shot glasses, whole cabbage leaves, et cetera at this time so that the refrigerated jars are ready to eat.

Something went wrong

Sometimes something will go wrong with your sauerkraut and you will feel tempted to toss it. There are very few times when this is really necessary so please don’t panic.

Mold growth. Sometimes mold will grow on top of the sauerkraut, especially if the cabbage has not been weighed down properly or if liquid was lost and the kraut is no longer completely submerged. If this happens, carefully remove the mold from the top. If you covered your cabbage with whole outer leaves then often only these leaves are affected; you can wash them well and reassemble. Add brine using the 1 teaspoon per cup ratio if necessary to augment the amount of brine in the fermentation vessel.

Insects. I have heard tales that sometimes flies will actually lay eggs in your fermenting cabbage. This cannot happen if you use a sealed fermentation vessel but some sauerkraut traditions call for covering the fermentation pot with a cloth which can sometimes slip aside enough to allow flies in. If this happens, remove the top inch or so of sauerkraut and discard. The larvae don’t go any deeper than this and the deeper sauerkraut will be fine.

No fermentation occurs. This can happen if your water was chlorinated, too hot, or if you somehow introduced some other antimicrobial compound into your sauerkraut. (Occasionally the cabbage itself will be sprayed with something that inhibits fermentation, which is why organic cabbage is preferred.) This problem is very rare, though, if you take precautions to avoid chlorine in your water (small amounts of chlorine, such as that from the water used to rinse your vegetables, are harmless).

It stinks! The fermentation process produces gases including methane gas so some aroma is unavoidable. The odor during the first week is not indicative of the final flavor. After the first week, the second wave of bacteria begin their work and the kraut begins to develop its sour flavor. During this time the kraut may smell distressingly gastric in nature from a distance but if you hold the open vessel to your nose you should detect a pleasantly tangy aroma. There is a scientific explanation for this; the “long distance smell” is caused by the methane gases trapped inside the vessel; when you open the vessel these gases are released. They smell distressingly like flatulence. However, the sauerkraut does not contain these gases nor does it have this smell. It has a fresh, tangy smell that is sharp but clean and pleasant.

If at any point however the sauerkraut smells like dead animals or dead fish then this could be a warning sign. Carefully check the brine surface and clear away any unwanted growth. If the submerged contents likewise smell unpleasant then throw away the batch. This has never happened to me but I have read about it on the internet. Its cause is usually attributed to too little salt.

The sauerkraut disappears from the fermentation vessel. This is most likely to happen if you live with other people, who will sometimes eat all of your sauerkraut behind your back. Make more next time; get the rest of the household to help with the chopping and tamping. (If they refuse to help but continue to eat all your kraut then you’ll have no choice but to move.)

It's too mushy. The most common cause is unwanted yeasts. This can be controlled by keeping your sauerkraut in a cooler location, or by refrigerating it after 2 or 3 weeks of fermentation. You can also try adding grape leaves or some other source of tannins to your kraut. (Oak leaves are said to preserve crunchiness when making lacto-fermented pickled cucumbers.) Finally, if you cannot control the room temperature then you can try increasing the salt, which will create an environment with too much salinity for most yeasts. However your kraut will also taste saltier so step up the salt gradually.

It's slimy. This is an unfortunate problem because it may also signal a ruined batch. The consensus on the internet seems to be that waiting a while will usually solve this issue. If you've waited several weeks after first noticing the sliminess and it hasn't cleared up then you should remove the top layers and discard. If the cabbage underneath smells tangy and is not slimy then just reseal. If the sliminess penetrates to the depths then you will have to discard the batch.

Discarding A Failed Batch

It is rare to have to discard a batch of sauerkraut; I have never had to do it. However, if you do discard a batch of sauerkraut, the best method of disposal is to drain the liquids into the sink and then discard the solids in a plastic bag. Alternatively, you can bury the solids in the yard or, if the amount is not overwhelming, use your garbage disposal. You should never compost sauerkraut as the salinity, acidity, and flora all act to interfere with the ecology and population dynamics of your compost (which is itself a type of fermentation process that relies on completely different dynamics).

Variations

The variations are endless and this section will barely scratch the surface. However, the simple version presented here is delicious as is so you don’t need to experiment further if you don’t’ want to. If you are adventurous, though, here are some suggestions:

  • Add juniper berries to the brine. This is a traditional combination popular in Germany.
  • Add sliced apples. This is another traditional sauerkraut admixture. Typically sour green apples are sliced thinly and layered into the fermentation vessel along with the cabbage.
  • Add chili peppers and garlic. This is very traditional in Korea, where they make a Korean version of sauerkraut called kimchee. You can add your own combination of chilies and peppers to the brine or search for kimchee recipes. Contrary to popular belief, not all kimchee recipes are spicy; in fact, not all of them use cabbage. Kimchee is the national dish of Korea, and it has even more variations than European sauerkraut. Many people believe that sauerkraut was first introduced to Europe by Genghis Khan and the Mongol horde, who are known to have relied upon a kimchee-like version of preserved cabbage as a staple food item using fermentation techniques acquired in Asia.
  • Add carrots. Carrots are chock full of healthful nutrients and are easy to add. Slice your carrots in whatever manner pleases you and add to the cabbage mixture. They do not alter the flavor noticeably but can improve the nutritional profile of your sauerkraut.
  • Add sea vegetables. Give your sauerkraut a nutritional boost by adding seaweed or other sea vegetables. These vegetables are chock full of unusual trace minerals and antioxidants. Use sparingly as their taste quickly becomes overwhelming.
  • Add grape leaves Grape leaves are often added to fermented cucumbers to keep them crunchy. (The procedure for fermenting cucumbers is not much different from making sauerkraut, except that they are submerged entirely in a saltwater brine instead of in their own juices.) I like to add grape leaves to my sauerkraut because I like it to stay crunchy. My sauerkraut is crunchy even when I get to the bottom of the crock, which can be several months after I first made the batch. I used grape leaves from a jar (see Figure 7) and I just place a few on the bottom of my crock before I start adding the shredded cabbage.
  • Add something else. I usually add bok choy for flavor, vitamins, and calcium. You can add whatever you want (within reason). There is an entire village in Poland where mashed potatoes are added to the sauerkraut to obtain an interesting texture and flavor.
  • Use collard greens instead of cabbage. This is common in the Southern U.S., where collard greens are plentiful. Many people call this “collard kraut” which is technically incorrect as it would translate to “collard cabbage”. I prefer to call fermented collard greens “sour collard greens". When soured, collard greens have a minty flavor and chewy texture that I find particularly pleasing. The recipe is basically the same as for sauerkraut. However, the procedure is a slightly different. I wash the leaves, then remove the thick part of the stems and set them aside. I then sliced the leaves with a knife to the same thickness as kraut. (I just roll up a bunch of leaves into a cigar shape and then slice the cigar.) I then chop the reserved stems into small segments and mix together before kneading, resting, and fermenting as with kraut.
  • Pickle something else. Once you have mastered the basic technique of making sauerkraut then why not try fermenting something else? Virtually any vegetable can be fermented. Those vegetables that do not produce enough juice to make their own brine can be fermented in a solution of 4 teaspoons salt for each quart of water (or one teaspoon of salt per cup). Remember to use de- or non-chlorinated water at room temperature. (Chlorine can be removed by filtration, boiling, or evaporation. It will also dissipate if the water is left out in the open for a day. Or you can buy non-chlorinated water or use well water.)

Figure 8. Sweet potato roasted on a bed of sour collard greens then brushed with coconut oil and sprinkled with cinnamon.

Serving Suggestions

The best way to eat homemade sauerkraut is raw. You may be used to rinsing your sauerkraut before using it; this is a useful step when eating commercial sauerkraut because it reduces the amount of sodium and some of the unpleasant commercial brine. The homemade brine is delicious and healthful, however, and should not be rinsed away.

Homemade sauerkraut can be heated just as commercial sauerkraut is heated and if you prepare it that way then the taste will be more like the commercial version. You will also kill off most of the beneficial probiotic bacteria and destroy the healthful enzymes, so you should not make a habit of cooking your sauerkraut. A compromise method is to steam the cabbage just until hot. This preserves most of the probiotics and enzymes.

Homemade sauerkraut is delicious served as is, right from the fermentation vessel. The brine can also be served as a tonic. It is a delicious beverage but unfortunately it is difficult to make it in quantities sufficient for drinking regularly. A shot of it though goes a long way towards calming an upset stomach and can help bolster your immunities if you feel a cold coming on. Sauerkraut juice is an old but effective folk remedy for ulcers and other digestive ailments.

Another favorite way of mine to serve raw homemade red cabbage is to drizzle it with sesame oil and mirin (a Japanese condiment made from sweet rice wine) and then sprinkle with sesame seeds and chia seeds. This healthful little salad is packed with essential fatty acids, vitamins, minerals, and of course probiotics and enzymes. (See Figure 9.) Only a small amount of sesame oil is needed as it has a very powerful flavor.

Figure 9. Red sauerkraut drizzled with sesame oil and mirin and sprinkled with sesame seeds, served with a cup of coconut kefir.

18 comments:

  1. I have just purchased a sauerkraut pot and I'm enthusiastic to get started. The only problem is that we have found it very difficult to locate organic cabbage locally. We have a small garden space, so growing our own isn't very practical and this one point is really blocking us right now.

    Obviously organic cabbage is preferable but is there a way to ensure that normal shop bought cabbage will ferment properly? I've heard you can use a little juice from existing sauerkraut to start the fermentation process. I don't know if non organic sauerkraut is really that useful though from a health perspective.

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  2. Hi, Ashley. I have never had any problems with store bought cabbage, even when not organic.

    I advise you not to use juice from existing sauerkraut. The process you describe is called "backslopping" and Dutch scientists have shown that it produces cabbage that is inferior in taste and consistency. The reasons are several:

    1) the juice you use as your starter is probably from finished sauerkraut, so the bacteria in that juice is representative of the last stage of fermentation. Sauerkraut relies on a different population of bacteria in the beginning phase to produce the correct lactic acid environment for later stages.
    2) if the juice you use as your starter is from commercial sauerkraut then it might also include other additives that inhibit bacteria growth.
    3) if the juice is from an earlier batch of homemade sauerkraut then you should be drinking it!

    I have bought cabbages from the supermarket, from Asian markets, and from several local farmers' markets. Just get the freshest cabbages you can find. If the cabbages are not fresh enough then you may have to add extra brine (made with 1 teaspoon salt per cup of water) but that is all you should need to add. I have never added any type of starter (neither cultures nor sauerkraut juice nor whey) and have always had great results. I am sure you will too!

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  3. Thanks Dave, that all very useful to know and I'll avoid using the existing sauerkraut juice. We had a little left over from some organic unpasteurised sauerkraut bought at a nearby health store. Needless to say it's more fun and much cheaper to make your own.

    We live in the English countryside with lots of local farms, so I'm a little surprised it's proving so tricky to find organic cabbages but it looks like they are all predestined for larger markets. The main objection I've heard to using cabbages from supermarkets is that they are often sent to market long before they are properly ripe and contain the proper nutrients. This is common among a lot of fruit and vegetables these days that are shipped very early to ensure maximum shelf life in the store.

    I shall try making a couple phone calls to see if we can find some organic cabbages locally but if not we may be able to find some via a farmers market. Recently we found some locally produced spinach at a grocers store and the taste is just so much better than when it has been transported across the world.

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  4. Hi, Ashley. If you are near a lot of local farms then you should be able to find fresh cabbage more easily than organic ones. And unfortunately organic doesn't necessarily mean fresh, and vice versa. Also, at this time of year local growers might not have a lot of cabbage on hand. You might want to make smaller batches until fall when the best cabbages are available.

    If you can get the red cabbages then I suggest those; they make a delicious sauerkraut!

    Cheers,
    Dave

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  5. Hi Dave,
    We are sandwiched between the world famous Eden project and the lost gardens of Heligan, so the struggle to find organic cabbage was almost surreal but we started our first batch four days ago using the newly acquired sauerkraut pot from Germany and armed with a printout of your blog post 8-)

    I think it went pretty well and after a day bubbles started to emerge every 30 seconds through the water funnel around the lid, which I guess means the fermentation process has begun. We used a mixture of red and white cabbage with sea salt, so we'll see how it works out and by the sound of it we can just leave it alone now for about a month before putting it straight in the jars and sidestep the whole fridge stage. I really think these pots could do with a peep hole so you can see what is happening in there but we've felt it better to leave alone so far.

    One slight point I wondered about was earlier today when I noticed the water outside the pot was rising to almost spill over the top and I figured this might mean we had put in too much water and or cabbage at the outset. I'll keep an eye on it.

    Thanks

    Ashley

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  6. Hi, Ashley. If the water along the rim is rising then you almost certainly overfilled your pot. Shame on you! (But if it makes you feel any better I make the same mistake almost every time. I just can't help myself!) Your sauerkraut will still be delicious, especially given that you've got some red cabbage in there. The red cabbage adds a lot of flavour and you'll love the results. But you should gently lift the pot into a larger container if possible to catch that overflow.

    I totally agree with the peep hole idea. One alternative to the peep hole that might also help your compulsion to overfill your pot is to put some into a mason jar. You can watch the mason jar and get a feel for what's going on inside the pot. They even sell airlock lids for the mason jars but I've made delicious sauerkraut with 100% scrounged and scavenged components (such as a shot glass to push the cabbage down as in the photo). I've been doing this lately and then I open the mason jar first, making sure the pot maintains its water seal.

    Once you've opened your pot you can either transfer all the sauerkraut into jars and begin refrigerating, or else just seal up the pot again. If you choose the latter then you will almost certainly get mold growth on the liquid's surface. You will also see mold on the sides of the pot above the liquid level unless you are scrupulous about cleaning the bits and pieces from those sides before sealing it up. Despite the disadvantages of leaving the kraut in the pot, this is what I usually do out of sheer laziness. The mold is unsightly but it's harmless, relatively easy to remove, and nobody else needs to know. ;-) Too much mixed into the kraut though will give it an off flavour so take care to remove as much mold as possible if you do get mold growth. (Or do you still spell it "mould"? I cannot remember...)

    I am a little envious; red cabbage is out of season here and my latest batch is nappa cabbage plus something called "Korean cabbage" which looks like a giant white cabbage that's been sat upon by a large person and thus slightly squashed in shape. The sauerkraut is good but not as good as the red cabbage. The juice (and thus the cabbage) is noticeably fizzy though. And nappa seems to make a lot of juice. And I mean a LOT. I not only got juice overflowing into the rim but into the plastic container that I had sat my pot in. (I told you that I often overfill my pot and I wasn't kidding, but I always put the pot in another container to catch the overflow. The same rectangular plastic container that I use to catch the cabbage as I slice it is also large enough to set the pot in while it's fermenting so that's what I do.)

    Anyway, after a week to ten days you will notice that the bubbling stops or at least slows down significantly and you will probably not overflow any more.

    Enjoy your sauerkraut and remember to drink the juice!

    Cheers,
    Dave

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  7. This comment has been removed by the author.

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  8. Hi Dave,
    I waited to give you an update until we opened the sauerkraut crock today after 18 days fermenting. Fortunately my wife had already taken the step of placing a plastic tray underneath to catch any liquid overfill but we needn't have worried.

    Opening the crock was a bit of a scary moment and I was fearing the worst because we had seen bits of mould appearing in the water seal outside but when we opened it there was only a really small amount around the lid opening that wiped off and none inside the actual sauerkraut. We tasted it and I'd have to say it's a real triumph. The red cabbage definitely has as a stronger taste but the jars with a nice red/white balance are really good and we've managed to pull out over 2 gallons from our first attempt. Best of all it's all unpasteurised so we should get the full benefits.

    We bought some half gallon jars from a store that specialises in this kind of thing and added a layer of olive oil on top so it all stays nice and airtight in there. It has all been transferred to the now but I've uploaded a picture for you to see here http://www.sunnymede.net/screenshots/sauerkraut.jpg

    Thanks

    Ashley
    PS Next time we want to try white cabbage, carrots and garlic.


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    1. Hi, Ashley. Congratulations on your first batch! It looks perfect. I'm glad you have plans to test all manner of other ferments; I do the same thing and have a bunch of pictures in my camera waiting to be blogged about. Once you get used to the mechanics you'll find you can ferment all manner of veggies, using your own brine if the veggies don't give up enough juices. The little bit of mould is not a problem. It's quite harmless and also unlikely to thrive in your fermenting pot until after you've opened it for the first time (at which point you let out the carbon dioxide and replace it with fresh air which gives the mould a chance to grow).

      And I see you've decanted all the kraut in your pot and readied it for longer term storage which is great because it will allow your kraut to keep longer and also frees up your pot! BTW those mason jars also work well for small experiments; I use them with the lid a quarter-turn counterclockwise from tight and then check them regularly for mould, removing it as soon as I see it. The mason jars don't have the air-tight seal so mould can grow but you also can open them up throughout. They do overflow easily though so be ready for that. You can save your "good" pot for larger batches of proven recipes.

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  9. Is it a really bad idea to add a fresh head of cabbage to a existing crock? I have had great success with my last attempts uninterrupted. I started a new batch exactly one week ago and today received another huge beautiful head of cabbage. Is it possible to add the fresh head?

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  10. Hi, Ryan. I would start a new batch. Use a mason jar if you don't have another crock. The reason is the phenomenon known as population dynamics. Basically, different bacteria take a lead role during different stages of fermentation. By the second week your sauerkraut has entered the second stage, so adding new cabbage now would interrupt that cycle. Also, the sauerkraut's juices will have diluted the salt by now thus allowing for the possibility that the whole batch will go bad due to the combination of lower salinity levels and newly introduced unfriendly bacteria.

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  11. Found your blog excessively interesting indeed. I really enjoyed studying it.
    homemade sauerkraut

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  12. Hi Dave,

    Thanks for your article! I've made my first batch sucessfully two days ago, it tastes great but as soon as I put it into the fridge for storage, the brine almost disappeared over night. I tried to press down the sauerkraut in order to release the brine out again, the brine did re-appeared but still not quite enough to cover all the sauerkraut. Should I add an inch of salted brine to it or just leave the sauerkraut expose above the surface of the brine in the fridge?
    Your advise would be very much appreciated. Thanks.

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  13. I would I can this or pickles to have through the winter

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  14. I have made my sauerkraut a month ago. I tried to taste it right out of the jar and it's way too salty and it's same as the brine in it. Did I have too much of the salt (1 cabbage with 3/4 tbsp salt) or do I need to rinses the salt out before eating it? I just don't know how to eat it. Thanks.

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  15. I have made my sauerkraut a month ago. I tried to taste it right out of the jar and it's way too salty and it's same as the brine in it. Did I have too much of the salt (1 cabbage with 3/4 tbsp salt) or do I need to rinses the salt out before eating it? I just don't know how to eat it. Thanks.

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  16. I just made my second batch of kraut. I felt that I used too much salt in the first one. I used less than half on the second. It had a white film that I skimmed off. The juice is a little milky after 2 weeks but I pulled up my big girl britches and grabbed a bite. It was still crunchy and tasted fine. Is it ok?

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