Micah Stanley
The tender, nutty-tasting kohlrabi is an enrichment in the kitchen and is also good for your health. The valuable roughage gets the intestines going and the numerous bioactive substances serve to prevent all kinds of ailments.
Kohlrabi belongs to the cabbage family
Like broccoli, Brussels sprouts, or kale, kohlrabi (Brassica oleracea var. gongylodes) is a variety of cabbage and, like any other cabbage, belongs to the large cruciferous family. Compared to the other cultivated forms, the kohlrabi is neither a leaf nor a flower vegetable, but a stalk or sprout vegetable.
Because what is eaten is the thickened, aboveground tuber, which thrives directly on the ground and arises from the underground part of the shoot axis. However, the almost mystical bulbous shape that characterizes kohlrabi today only developed in the last few centuries. Before, the kohlrabi bulbs were cone-shaped and much smaller.
Where does the kohlrabi come from?
The kohlrabi is anything but exotic – and yet it is a plant shrouded in mystery. Because nobody knows how long it has existed and where its origins lie. The oldest sources date back to the 16th century and were written in German.
It is therefore assumed that the tuber originated in northern Europe and may even have come from Germany. This is also supported by the fact that kohlrabi is primarily cultivated and enjoyed in this country today. In other countries, it is even regarded as such a typically German vegetable that even the Japanese, Russians, English, Spaniards, and Americans call it “Kohlrabi”.
In the eastern and southern coastal regions of Spain, for example, the tuber is considered an exotic vegetable that is only offered in really well-stocked shops or at selected vegetable stands and that was not even commercially available until a few years ago. Many Spaniards are therefore not familiar with kohlrabi and – when they see it – do not know how to prepare it either.
Curiously, the tuber is a very popular vegetable in Vietnam, India, Kashmir, Bangladesh, Sri Lanka, and Cyprus. While in Kashmiri it is prepared with leaves and served with a light soup and rice, Cypriots serve it as an appetizer, drizzled with salt and lemon juice.
Kohlrabi with many different names
In German-speaking countries, the popular tuber has many names. Translated, the term kohlrabi means nothing more than swede. But it is only called that in Vienna because elsewhere it means swede. In Switzerland, kohlrabi is called Rübkohl. The kohlrabi is referred to as upper kohlrabi or top turnip because it looks like a turnip that grows above the ground.
The Calories
A fresh, i.e. raw, kohlrabi has 25 kcal per 100 g. A cooked 20 kcal per 100 g.
The nutritional values
Like all vegetables, kohlrabi is very rich in water and low in fat. It contains the following nutrients (each per 100 g of raw kohlrabi):
- water 92 g
- Carbohydrates 4 g (of which 1.3 g glucose and 1.1 g fructose)
- protein 2 g
- Fiber 2g
- Fat 0.1g
The vitamins and minerals
In terms of the high vitamin content, kohlrabi cannot necessarily keep up with other cabbage vegetables such as broccoli or Brussels sprouts. But there is more vitamin C in kohlrabi than in lemons and oranges: If you eat a single portion of 150 g of raw kohlrabi, you can cover almost 100 percent of the officially recommended daily requirement of vitamin C.
You can find detailed information about all the vitamins, nutritional values, and minerals contained in 100 g of fresh (raw) kohlrabi in our table: Nutritional values in kohlrabi
The mustard oil glycosides
Kohlrabi is not only a good source of vitamins and minerals, but it also contains very special substances that are exclusively found in cruciferous vegetables. The so-called mustard oil glycosides are sulfur compounds that are counted among the secondary plant substances. They are actually responsible for protecting plants from voracious insects.
Each cabbage vegetable is characterized by the presence and dominance of certain mustard oil glycosides so that a fingerprint is created, so to speak. The most important mustard oil glycosides in kohlrabi include glucoraphanin and glucobrassicin.
As far as the total content of mustard oil glycosides is concerned, according to analyzes by the University of Oradea, broccoli leads the hit list of all cabbage varieties with 19 to 127 milligrams per 100 grams of fresh vegetables. But the kohlrabi also knows how to convince with 20 to 110 milligrams of mustard oil glycosides. In comparison, the total content of cauliflower is only between 11 and 78 milligrams.
However, it is not the mustard oil glycosides that are responsible for the characteristic taste and healing properties of kohlrabi, but the mustard oils that are produced from them.
Other secondary plant substances
In addition to the mustard oil glycosides, kohlrabi contains many other secondary plant substances, including carotenoids such as beta-carotene and various phenolic compounds such as catechin, quercetin, kaempferol, and anthocyanins. All of these substances act as radical scavengers, strengthen the immune system and reduce u. the risk of cardiovascular disease and cancer.
Are blue-purple tubers healthier than green ones?
Blue-purple kohlrabi is by no means a modern-day achievement. In a garden magazine from 1815, varieties such as the “Early Blue Glaskohlrabi” were already mentioned. They are not only particularly pretty to look at, but also have a lot ahead of the green variant. Anthocyanins, which are among the strongest antioxidants, are responsible for the blaze of color.
Researchers from Chonbuk National University compared green and blue-purple kohlrabi and concluded that the latter have higher phenolic content and, as a result, have significantly more potent antioxidant, antidiabetic and anti-inflammatory properties. However, you should also eat the skin, which is not a problem with young kohlrabi.
The healthy fiber in kohlrabi
Cabbage has been known for its digestive properties for thousands of years. For this are u. a. the dietary fibers contained are responsible. It’s no longer a secret that people who eat a diet rich in fiber are less likely to develop chronic diseases. Kohlrabi and other cabbage vegetables contain far less fiber than legumes and cereals.
According to various studies, however, the protective effect against diseases primarily applies to high-fiber vegetables such as kohlrabi. This suggests that the fiber interacts with other substances in the collard greens. An English study has shown that the risk of colon cancer is reduced only through the interaction of roughage, mustard oils, and polyphenols.
A wonderful anti-stress vegetable
The kohlrabi contains interesting amounts of magnesium. For example, if you eat 200 g of turnip greens, you cover 40 percent of your daily magnesium requirement. Since magnesium is also considered an anti-stress mineral, one could now also call kohlrabi an anti-stress vegetable.
Because magnesium dampens exactly those messenger substances that are released as a result of stress. As a result, magnesium-rich foods such as kohlrabi also have a protective function in relation to restlessness, irritability, migraines, depressive moods, and sleep disorders.
In addition, a study at American University in 2018 showed that magnesium can even have a positive effect on mental illnesses such as depression and phobias and neurological conditions such as Parkinson’s and Alzheimer’s.
Where is kohlrabi grown?
In Germany, most kohlrabi is not only eaten but also cultivated. Around 50 varieties are cultivated in an area of approx. 2,300 hectares and around 40,000 tons are harvested annually. The main growing areas include Bavaria, Baden-Württemberg, and North Rhine-Westphalia.
Kohlrabi is available all year round. The regional vegetables come from the greenhouse from April to June and from outdoor cultivation from July to November. Basically, the finer and more delicate green varieties usually come from greenhouses, while the spicier and stronger blue-violet varieties are mainly cultivated outdoors.
Other growing countries are the Netherlands, France, Poland, Romania, Austria, and Switzerland. The kohlrabi grown in southern and south-eastern European countries is almost exclusively exported to Germany.
You should pay attention to this when buying
If you buy kohlrabi with leaves, they give you information about the freshness of the tubers. Because if the leaves are crisp and green (or blue), the tuber itself is usually of good quality. When buying, make sure that the outer skin of the tubers is undamaged and smooth. The smaller the tubers are, the more tender they taste. Large kohlrabi bulbs, on the other hand, can be woody on the inside.
However, there are also very large kohlrabi varieties, e.g. B. the so-called super melt – giant kohlrabi of buttery quality. Therefore, in the case of large tubers, ask for the variety if it is not already listed.
Is kohlrabi heavily contaminated with pesticides?
Analyzes by the chemical and veterinary investigation office in Stuttgart showed again in 2018 that organic kohlrabis are preferable to those from conventional cultivation. Because of 19 conventional samples, 16 (84 percent) were contaminated with residues. Of these, 7 samples showed multiple residues.
In 4 samples, the permitted maximum amount was even exceeded. These included chlorate, which according to the Federal Institute for Risk Assessment inhibits iodine uptake and, in higher concentrations, can damage the red blood cells, and the neurotoxic active ingredient omethoate, which is actually no longer permitted in German-speaking countries.
Dimethoate, which is toxic to bees, butterflies, and even small mammals, is classified as particularly problematic. This insecticide was already banned in France in 2016 due to health concerns, as it e.g. can damage the nervous system. The Federal Office for Risk Assessment announced that an extension of the approval for dimethoate beyond 2019 would be problematic.
Kohlrabi can easily be frozen
You can easily freeze kohlrabi. First cut the tuber into slices or pieces, blanch them for a few minutes and shock them in ice water. You can then put the vegetables in portions in suitable containers and freeze them. Frozen kohlrabi will keep for about 9 months, but won’t be as crisp after that.
Should the kohlrabi be peeled?
While young, small kohlrabi can be eaten with the shell, the outer skin of larger specimens is quite hard or even woody. In this case, it is better to peel kohlrabi.
However, this has the disadvantage that valuable bioactive substances are also removed since these are located in or directly under the shell. Analyzes by Korean researchers have shown that the carotenoid content in the skin is much higher than in the interior of the vegetable.
This is how the kohlrabi is prepared
Before you prepare the kohlrabi, you should remove the leaves and clean the tuber thoroughly under running water. Now you can cut off the lower end generously with a sharp knife and cut away any fibrous or woody parts.
You can then peel the kohlrabi, if necessary, and then cut it into slices, cubes, sticks, or strips. If you would like to enjoy the tuber raw, you can grate it wonderfully on a kitchen grater or cut it wafer-thin with a mandolin.
How is stuffed kohlrabi prepared?
Boil the whole bulb in salted water as above, hollow out the inside, and place your favorite filling inside. Fill a casserole dish with some liquid, put the stuffed kohlrabi on top, and bake them in an oven preheated to 200 °C with top and bottom heat for about 25 minutes. In the end, you can taste the kohlrabi vegetables again.
How are kohlrabi chips prepared?
Cut the tuber into slices as thin as possible, dry them with a kitchen towel and put them in a dehydrator or dry them in the oven at 50 degrees.
A conventional but far less healthy method of making chips would be this: Roll the thin slices of kohlrabi in cornstarch. Then put oil in your fryer or in a saucepan and heat it to 180°C.
Then you can put the kohlrabi slices in small portions in the hot oil and fry them until they are golden brown. Remove the chips from the fat with a slotted spoon and drain well on a plate lined with paper towels.
