As cooking goes, the heat of boiling (100 C=212 F) is moderate. It does not alter most foods to the point of sometimes rendering them harmful, like frying or roasting. On the other hand, boiling lasts a long time and takes place in a liquid medium, usually water. This causes many of the food's micro-ingredients to go into solution. If you throw away the water used for boiling, you may be discarding a great deal of the best this food had to offer. We know that boiling results in a 40 percent loss of B vitamins and 50 percent of folates, perhaps the entire content of vitamin C, and a variable loss in minerals. This is neither intelligent, nor thrifty, nor useful. What can you do instead? Well for one, this is a good reason for favoring soups, especially vegetable soups. For another, look under Asparagus below for an idea, but remember that this is only one example. If you are to get the most out of our foods, you must use your intelligence, imagination and native inventiveness as if your life depends on it. And make no mistake-it does.
Boiling asparagus is probably best done in the following way. Get a high saucepan in which you can stand the asparagus upright. Lacking that, arrange a bain marie, using a saucepan and a glass jar of the right size. Trim the bases of the stalks so the tops are all level. Put enough water in the saucepan or glass jar to reach to about three inches (8cm) from the tips. Boil for 20-40 minutes depending on stalk thickness, leaving the saucepan cover off. This way the edible tips are steamed, not boiled. Serve on thick toast dipped in the water the stalks are boiled. This way you get some of the beneficial compounds dissolved from the asparagus stalks.
One problem with eating beans is gas. It makes people sufficiently uncomfortable to give up eating these beneficial legumes altogether. But there are a couple of things you can do to ease the problem. First, try parboiling the beans, throw away the first water and replace with fresh water, and continue boiling till done. It is better to lose some ingredients, than stop eating these low glycemic index foods. Second, try taking some digestive enzymes, particularly special bean enzymes.
As a member of the cruciferous brassica family of plants, broccoli deserve better than being boiled. Cut to the appropriate size, and instead stir-fry these in a wok for no more than two minutes. On how to best stir-fry vegetables in a wok, see under Frying.
Cabbage, another member of the cruciferous plants, is better eaten raw as cole slaw. Mix with grated raw carrots to give additional benefits and color. If you must cook cabbage, make into a soup.
Eat carrots preferably raw, as when cooked they have a high glycemic index. Carrots, but also cucumbers, celery, cauliflower, and the hard stems of lettuce, can be used with an appropriate dip or two. Cut thin long stalks of these and use to pick up some of the dip. Taken as a snack between meals these can modify your appetite, while at the same time getting the full benefit of their ingredients.
The same remarks apply here as for broccoli. But fresh raw cauliflower has a subtle scent and pleasant taste, and can be eaten raw with a dip.
People like large fish with lots of flesh that may be plastered with sauces. But do not underestimate small fish. Finger size fish may be eaten whole, if you are not overly squeamish, when you get some of the most bioavailable calcium from the tiny bone, as well as the benefits of its long chain fatty acids. Fresh fish is incontestably best. Choose shamelessly the fattest fish, but some like belted bonito may spoil quickly. Remember, you can eat fish cold with horseradish sauce, if you are not allergic to allyl isothiocyanate, an oil found in horseradish.
Cooked potatoes have almost invariably a high glycemic index. As the potato cools, the starch retrogrades and its glycemic index is reduced. But cold baked and fried potatoes taste like recycled cardboard, and they cannot be warmly recommended. It is different with boiled potatoes or potato salad. Cold boiled potatoes with some good olive oil and a sprinkling of fresh parsley and oregano, are perfectly edible. And potato salad made with low-fat mayonnaise can only be eaten cold.
There are many kinds of rice, from the stickily gluey to the individually fluffy. But unlike most cereals that are milled into flour, rice is mostly used as the polished grain. Polishing removes the bran layer and this causes substantial losses in B vitamins. But when the unhusked rice is parboiled, the water soluble components such as its vitamins migrate into the grain together with some of the oil. In other words, the process of parboiling unhusked rice preserves the aleurone layer with the grain, and the beneficial ingredients are not lost when the bran layers are milled off.
Spinach is one of the green leafy vegetables, like parsley, dill, chervil and samphire, with strong flavors and hence often used as herbs. It has been thought that spinach is a great source of iron, but only 2 percent of it is bioavailable. To enhance its iron absorption, serve with lemon or other vitamin C source.