The highly diverse genus, brassica includes the vegetable we know as cabbage. Depending on your first cabbage experience, you will either love or hate this vegetable. Unfortunately, cabbage has been much maligned by improper handling and poor cooking. Don't let these culinary crimes put you off this noble and versatile vegetable - better yet, let's find out how to treat cabbage with the respect it deserves.
Apart from the familiar varieties of heading cabbage, there are also dozens of non-heading; leaf, stem and flower based cabbages from around the world, each with its own unique place in divergent cuisines and their methods of preparation.
History
Cabbages are an extremely popular vegetable in Europe, Africa, through Central Asia and right out to Far East Asia. The regular heading cabbage most of us would be familiar with has its parentage with the wild cabbage that is native to coastal areas of the Mediterranean. This plant would have been gathered for countless millennia, but the first record of its domestication dates to around 2500 BC. This vegetable was thought of very highly by the Romans, and was even believed to counter some of the excess to which that society was prone. According to Cato,
"The cabbage surpasses all other vegetables. If, at a banquet, you wish to dine a lot and enjoy your dinner, then eat as much cabbage as you wish...It will make you feel as if you had not eaten, and you can drink as much as you like."
It was most likely the Romans who were responsible for the introduction of wild cabbage to the British Isles.
Sometime later, after centuries of domestication and due to selective selection of forma when planting new crops, cabbages started to form heads. The regular round, white and tightly packed cabbage you see in greengrocers everywhere made its first appearance circa 1100 AD, around the area we know as Germany. Cabbage's Lilliputian cousin, the Brussels sprout was first extensively recorded in 1587, although evidence of this vegetable in Northern Europe pre-dates this by almost 1000 years.
Chemistry
When cooked, cabbages have a lot going on in the chemistry department. The cabbage group of vegetables has been thoroughly investigated by chemists, and indeed perhaps the first detailed study of what chemically occurs to a cooked vegetable was undertaken with cabbages in 1928.
There are a couple of reasons behind early scientific interest. Firstly, cabbages are a stinky vegetable - there is little avoiding this fact. They give off a range of malodiferous substances as they cook. Secondly, and more ominously, the cabbage family includes mustard and horseradish, both of which contain powerful isothiocyanate compounds that were synthesized during World War I to produce the horrific mustard gas.
Among the aromatic compounds released as cabbage is exposed to heat are hydrogen sulfide (rotten egg gas), ammonia, mercaptans and methyl sulfide. The longer cabbage is cooked, the more prodigious is the resultant gaseous output. Eventually, after a prolonged period of cooking, powerful and unpleasant tri-sulfides will be formed. To make matters worse, aluminium cookware reacts poorly with cabbages. The oxides in the metal interact in an unpleasant manner with the sulfurous material in the vegetable.
Much of this can be avoided by cooking cabbage for brief periods of time and in non-aluminium cookware. For instance, the amount of hydrogen sulfide produced by cabbages doubles from the 5th to 7th minute of cooking. If you need any other reasons to avoid long-boiled cabbage, this is it.
Varieties
European cabbage
Heading cabbage, which includes the regular white, the crinkly savoy and the vivid red cabbages, as well as tiny Brussels sprouts all belong to one diverse species, Brassica oleracea. All parts of these cabbages are edible, including the coarse white stem running up the middle of the vegetable. Any limp outer-leaves need to be removed and depending on the preparation, will either be shredded, for quickly braised dishes and salads, or in the case of stuffed cabbage, the leaves are removed whole. Owing to Brussels sprouts' small size, they are either left whole, or cut into wedges.
Flowering cabbage includes broccoli and cauliflower, as well as their faddish hybrid progeny, the broccoflower. All parts of these varieties are edible; stems, leaves and inflorescence. In the case of cauliflower, the large leaves are encouraged to grow over the vegetable during growth, thus inhibiting the production of chlorophyll that would taint cauliflower's trademark pale colour. These varieties are generally cut or snapped into individual flowering heads, known as florets, before proceeding with a recipe. The exception is some elaborate European and Indian cauliflower preparations, which require the entire vegetable to be cooked whole.
Stem cabbage is mainly represented by one strikingly presented vegetable, the kohlrabi. This cabbage varies in size from a tennis ball, up to a large grapefruit and usually sports a vivid purple exterior; apart form a pale green variety that is sometimes available. It grows in an intriguing manner - the stem abruptly swells to an alarming width, with the leaf containing branches growing upwards from the swollen stem. Generally, kohlrabi is sold minus the leaves, but they are as well edible. Due to the dense, root vegetable-like texture of kohlrabi, it is normally sliced into smaller wedges before cooking.
Leafy cabbage is an extensive group, which includes the original wild cabbage, kale and the black-leafed Italian cavolo nero. These cabbages do not form heads and thus all of the culinary action is to be found in separate leaves. They should be treated in a manner similar to spinach or silver beet, with their slightly coarser texture dictating perhaps a minute or so more cooking time. Make sure to wash these leafy cabbages well before use.
Asian cabbage
I have deliberately kept this section separate, as although these cabbages have many similarities to their Euro cousins, their treatment is sufficiently different to warrant stand-alone status.
Chinese cabbage Brassica pekinensis is also known by its Chinese name - won nga buck, as well as Peking cabbage and Napa cabbage. It is loose-headed, with white to pale green leaves and a distinctive elongated shape. They are quite large, with the average sized football making a small specimen. These cabbages are either sliced into small sections for stir-frying or soups, or more often than not - pickled. This is done in either the Chinese manner, finely shredded and subtly spiced - which some food historians believe to be the precursor to sauerkraut; or in the Korean style, kimchi. This addictive and volatile preparation is highly spiced and includes a goodly amount of fiery red chilli.
Chinese broccoli B. alboglabra is also commonly known by its Chinese name, gai larn. This variety has light green, thick stems and coarse, dark green leaves. It is commonly found in stir-fries and soups, as well as the ubiquitous dish found on Chinese menus simply as "Chinese vegetable". This is lightly steamed gai larn dressed with oyster sauce, ginger and stock.
Bok choy B. chinensis is also sometimes sold as Shanghai cabbage. It possesses wide, succulent and pale stems with uniform mid-green leaves. This cabbage is once again popular in soups as well as in famous Cantonese dishes such as mermaid's tresses and lion's head meatballs. A variation is rosette bok choy B. chinensis var. rosularis, which has deeper green, round leaves and grows in an attractive and compact rose shape.
Choy sum B. chinensis var. parachinensis is also known as flowering cabbage. It has long, pale and tender stems and mid-green leaves. This variety is often sold with compact yellow flowers, hence its common name.
Mustard cabbage B. juncea is known in Chinese as gai choy. This cabbage has coarse and thick stems, somewhat reminiscent of bok choy and dark, frilly foliage. Mustard cabbage has a pungent, slightly bitter flavour that is prized for use in strongly flavoured soups. This is the cabbage used in the powerful condiment - Szechwan pickled cabbage.