Ingredient of the Month 15: Kale

L-R: Purple curly kale, cavalo nero, ragged Jack

Jersey Cabbage, a traditional kale from the Channel Islands

Ragged Jack, another heritage kale from the UK

Kale, or "borecole",  is without doubt one of the most nourishing foods you can eat: there's something about its vibrancy when you see it growing that kind of tells you that anyway. (The photos of our own kale above were taken with my mobile phone a couple of years ago in Spring and I hope they illustrate this.) Kale is a member of the brassica family (which includes cabbages, collards and broccoli), being different from cabbage in that its central leaves do not form a "head". It seems to be able to grow anywhere, from Congo and Kenya, Scandinavia and Ireland to China and Japan, and was once called "hungry gap" as it grows well in Winter, when there is little or nothing else available in field or garden. -In fact, kale is more sweet and tender after it has been touched by a frost, and you will also find that it keeps really well in the freezer. In Scotland, kale was traditionally grown in "kaleyards", protected from the wind by stone walls.  We grow several kinds of kale in our allotment, in a cage to stop the pigeons from eating it all. We have trendy cavalo nero (aka Tuscan black kale), tender Chinese Kailan, frothy-leaved curly kale, colourful Ragged Jack and tall (and somewhat tougher) Jersey kale. They make an attractive Winter display; a lush island of greenery amid brown, bare soil.

Nutrition:

This is where kale really comes into its own, as it has been hailed as a "superfood" for its outstanding nutritional profile. It contains high levels of beta carotene, vitamin K,vitamin C, lutein, zeaxanthin and calcium. It even contains some protein, vitamin E, iron and omega 3 oils, amongst numerous other nutrients.

• There are 45 different flavonoids in kale, which include kaempferol and quercetin. These are both antioxidant and antinflammatory and great for preventing/ alleviating chronic inflammation and oxidative stress (the damage that free radicals do). 
• One of kale's more well-known and researched benefits is that it contains a double whammy against cancer: first up is sulphoraphane, a chemical with potent anti-cancer properties. Chopping the kale finely will bring this out more, but boiling will decrease the sulphoraphane levels. (It has been found, however, that steaming or stir-frying kale don't result in much of a loss.) Kale's anti-cancer weapons number 2 are isothiocyanates (ITCs) which can significantly lower the risk of cancer of the bladder, breast, colon, ovary and prostate.  One of these is indole-3-carbinol, which actually detoxes and repairs the body at DNA level, and appears to block the growth of cancer cells.
• We all know that green vegetables are a great source of fibre, but did you know that the fibre-related components in steamed kale can also lower chloresterol levels? They do this by binding together with bile acids in the digestive tract to excrete them more effectively. (Raw kale also does this, but not quite as well.)

Cooking:

Teamed with black or cannellini beans, cavalo nero makes a delicious healthy Italian soup, although I must confess to liking kale better raw or dehydrated than cooked. I don't really like its texture if it's served up to me as a plain steamed vegetable, and find it quite difficult to chew and swallow. (The kids, however, love it that way and take great delight in telling me to eat up my greens!) Kale is great in stir fries. If, like me, you find it a little tough, it can be shredded finely; this not only renders it much easier to eat, but also activates the cancer-preventing compounds (see above). I think it would also be great shredded and baked in soy sauce to make "crispy seaweed", although I'm not sure to what extent baking would adversely affect the nutrients in it. (Let me know if you have tried this.) When faced with a bag of enormous Jersey kale leaves, I tend to steam them in the pressure cooker, blitz them in the food processor and turn them into a sag-style Indian dish with spices and a little oil. My husband also chops and pressure-cooks them with halved fresh tomatoes. The acid in the tomatoes seems to tenderise the kale leaves somewhat. Apart from munching the young leaves raw in the garden, my new favourite way with kale is to make kale chips- Yummy and crispy, and packed with all those health-giving substances...