When vegetables are least plentiful, it is particularly important that they should be carefully cooked to avoid losses of vitamins and minerals.
By a happy chance, those vegetables richest in vitamins and also provide the highest amount of minerals-iron, copper, calcium, potassium and phosphorus.
Be careful of cooking the vegetables to conserve vitamins also reduces losses of these valuable nutrients.
Briefly the results of recent research can be summarized for the cook as follows:
- All vegetables should be served fresh-straight from the garden or as soon after purchase as possible, because vegetables tend to lose their vitamin during storage.
- The outer leaves of all green vegetables are rich in vitamins, so reduce the waste in preparation to a minimum. The very tough outer leaves can be put in the boiling cooking water for a few minutes to enrich the water, and then be removed before the more palatable parts are put in. These are then cooked in water already containing some vitamins, which reduces the tendency to further extraction.
- Potatoes should be baked or boiled in their jackets for full food value, as there is no loss of vitamins unless the skin is broken. Frying in hot fat is also a good method of cooking potatoes to conserve the vitamins.
- Cook vegetables as quickly as possible and avoid keeping them hot. Slow cooking destroys the vitamin, plunge vegetables into quickly boiling water and cook them for as short a time as possible. All green vegetables, in any case, have a much better texture and color if cooked for only 10 to 15 minutes.
- Use the water in which vegetables have been cooked for soups, sauces and gravies, because vitamin dissolves very readily in the water.
- Serve vegetables immediately after cooking. As green vegetables and mashed potatoes lose a great deal of vitamin when kept hot, time the cooking process carefully so that vegetables are ready to serve at the right moment. Don’t use bicarbonate of soda with greens.
- Fine shredding of vegetables increases the destruction of vitamin. If you chop parsley or watercress for a garnish or shred cabbage for a salad, do it just before serving. Root vegetables however lose more vitamins if they are cooked in large chunks, because of the slower penetration of the heat. They should be sliced and cooked in quickly-boiling water.