Even though the inside of cabbage is usually clean since the outer leaves protect it, you still may want to clean it. Remove the thick fibrous outer leaves and cut the cabbage into pieces and then wash under running water.
If you notice any signs of worms or insects, which sometimes appears in cabbage, soak the head in salt water or vinegar water for 15-20 minutes first. To preserve its vitamin C content, cut and wash the cabbage right before cooking or eating it. Since phytonutrients in the cabbage react with carbon steel and turn the leaves black, use a stainless steel knife to cut.
To cut cabbage into smaller pieces, first quarter it and remove the core. Cabbage can be cut into slices of varying thickness, grated by hand or shredded in a food processor.
Proper cabbage preparation and cooking methods can be essential when it comes to getting the most benefits from cabbage. In one study that compared steaming to microwaving of raw cabbage, researchers found that it took 7 minutes of steaming to result in the same amount of enzyme (myrosinase) destruction that occurred with only 2 minutes of microwaving. In other words, short steaming was much better than microwaving for preserving some myrosinase activity in the cabbage. Since we need myrosinase activity to convert the glucosinolates in cabbage to cancer-preventive isothiocyanates (ITCs), preservation of as much myrosinase activity as possible when cooking cabbage seems worthwhile. Researchers have some proof that light steaming actually works because they have found higher concentrations of one particular isothiocyanate (AITC, or allyl-isothiocyanate) in lightly steamed cabbage. AITC has the ability to help lower risk of certain cancers (including bladder, breast, colon and prostate cancer). This recent research finding underscores the value of light steaming as a way to preserve anti-cancer benefits when cooking cabbage.
It's worth adding here that a little bit of bitterness in the taste of cabbage is not necessarily a bad thing when it comes to your health. Although the commercial food industry sometimes tries to remove bitter-tasting constituents from cruciferous vegetables through hybridization of different cabbage varieties, some of the bitter-tasting constituents—including sinigrin, one of the glucosinolates especially plentiful in cabbage—is the source of the anti-cancer substance AITC discussed in the previous paragraph. Rather than attempting to completely eliminate the natural bitterness of cabbage, we would be much better off from a health standpoint weaving cabbage into a recipe that included differently flavored foods in such a way that the cabbage was allowed to retain a little of its natural and noticeable bitterness but within a blended-flavor context of a delicious dish! For example, our Gingered Cabbage provides you a wonderful sweet and sour flavor.
Finally, it's important to remember that we can allow myrosinase enzymes in cabbage to do their natural work by slicing, shredding, or chopping raw cabbage and letting it sit for 5-10 minutes before cooking. Once the cells in cabbage have been broken apart through slicing, shredding, or chopping, the myrosinase enzymes in those cells can become active in converting the glucosinolates in cabbage into isothiocyanates (ITCs).