Cabbage is a challenging vegetable. By that, I mean eating a whole head of cabbage could be a competitive sport. Buying half heads of cabbage might give an advantage to eliminating food waste. If you still find left over cabbage hiding in your refrigerator, sauerkraut could be the solution. It takes three simple ingredients: cabbage, water, and salt.
So what is sauerkraut?
Even though sauerkraut is considered a staple of German cuisine the origins are more likely Asian. Think of it as a less spicy kimchi. Eating fThey are considered living foods because they contain bacteria or probiotics that have been shown to improve digestion and the function of the GI tract. Sauerkraut contains dietary fiber, vitamin A, vitamin C, vitamin K, and B vitamins. It is also considered a good source of iron, manganese, copper, magnesium, and calcium.
Fermentation (Cabbage + Salt) x time = Suerkraut
Fermentation is a natural way to preserve food. Fermented foods such as sauerkraut have an expected shelf life of 1 to 2 years. Cabbage is transformed into sauerkraut by friendly bacteria known as lactic acid bacteria (LAB). They are the workforce involved in transforming perishable foods into shelf-stable products. Cabbage naturally contains bacteria such as Leuconostoc mesenteroides and Lactobacillus plantarum. If these names sound familiar, it is because they are also found in dairy products such as yogurt and cheese, and sourdough starters.
So let’s take a closer look at what happens when cabbage water and salt get together.
Cabbage, salt, and water get comfortable in an airtight jar or fermenter. Since fermentation is an anaerobic process, the LAB or probiotic workforce wake up and begin to consume sugars (aka carbs) naturally present in the cabbage. As the worker’s break down sugars, lactic acid, alcohol, and carbon dioxide are produced. Fermentation of cabbage has a gaseous and nongaseous stage.
The initial stage is considered gaseous. The rapid production of C02 causes something known as gaseous brine upheaval. Heaving is caused by gas bubbles getting trapped in the sauerkraut. At this stage, you may notice the volume of the kraut has increased and has risen to the top of the container. The kraut should be weighted to keep it submerged preventing exposure to air. Exposure to air may cause an off flavor in the finished sauerkraut.
During this stage the growth of LAB L. mesenteroides increases, lactic and acetic acids increase, the pH is reduced, LAB produces ethanol and mannitol, and sugar is consumed.
The second stage is considered a nongaseous stage. The brine upheaval that marks the beginning of fermentation stabilizes, there is little to no production of CO2, the growth of LAB L. plantarum begins, lactic acid increases, all remaining sugar is depleted, and a gradual decrease in pH is observed.
The sour, salty, crunch characteristics of sauerkraut are influenced by the fermentation temperature. It should be fermented at 64-76°F/ 18-24°C for 1 to 6 weeks. Higher fermentation temperatures increase the growth of lactic acid bacteria which will give a sharper sour flavor.
Turning cabbage into sauerkraut is an easy way to give cabbage a second life. It can be made in quantities ranging from a small mason jar all the way up to a large vat. The equipment needed to make sauerkraut is inexpensive and easy to find. Kits are available that can simplify the process if you are just getting started. Glass and ceramic are preferred over metallic containers, and a cylinder shape with a large opening will make pressing the cabbage below the water level much easier. Leftover cabbage can easily be made into sauerkraut extending the shelf-life up to 2 years in as little as two weeks.
For more information on fermentation and turning cabbage into sauerkraut check out these resources:
- A detailed study fermentation that explores the process of making sauerkraut – Fleming, H. P., R. F. McFeeters, and Ervin G. Humphries. “A fermentor for study of sauerkraut fermentation.” Biotechnology and Bioengineering 31.3 (1988): 189-197.
- An overview of the health benefits associated with consuming sauerkraut. https://www.organicfacts.net/health-benefits/other/sauerkraut.html
- Recipes, troubleshooting, and everything else related to sauerkraut visit www.wildfermentation.com
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