Rosalee Brown

Last time, we spoke about choosing the best vegetables based on textures and flavours. Today, let's look at cooking vegetables of various colours.

Add lemon juice

The pigmentation of vegetables is very important as they contain different phytochemicals which are beneficial to health preservation. The pigments in vegetables react very differently to acids and other agents in the cooking process. Vegetables such as cauliflower and other white pigment vegetables can get an off colour or 'yellowish' in an alkaline medium, such as your tap water, but will maintain their white colour in an acid medium.

So, adding a small amount of acid such as lime and lemon juice to the veggies before or during cooking will do the trick. Remember though that acid can toughen the vegetable, so do not add too much. Cooking for a short time or in a steamer helps to maintain the colour, but the vegetables should be served immediately.

Red pigments such as those found in purple cabbage, beets and blue berries react both to acids and alkalis. Acids will make the reds more brilliant and alkalis will turn them bluish. A very small amount of acid or an acid fruit will enhance the colour during cooking. Use the smallest amount of water necessary and cook for a short time. Cook beets in their skin to preserve colour. Do not steam red cabbage with other vegetables. To prevent discoloration, steam in an unperforated steamer to maintain colour.

Green and yellow

Green vegetables react strongly to acids (such as tomato products) as with long cooking. Cook green vegetables uncovered to allow acids to escape, cook for a short time and cook and serve immediately.

Yellow and orange pigments are found in yellow vegetables but also in tomatoes and red peppers. They are quite stable and are not easily affected by acids or alkalis. Long cooking, however, will affect the brilliance in the colours, so the rule of cooking for a short time is important in colour preservation.

Short cooking time

One reason vegetables are important, is for their nutritive quality. They are rich sources of vitamins and minerals. However, some of the vitamins can be destroyed by heat or can dissolve in water. Therefore, proper cooking methods should be chosen to reduce this.

Depending on the texture of the vegetable and the intended final product, choose a cooking method that uses minimum water, the shortest cooking time and serve vegetables immediately. If vegetables are steamed in water, re-use this liquid in sauces, soups or for cooking rice dishes. It can also be frozen for later use. Try to cut vegetables in uniform sizes so cooking of all pieces is completed at the same time, to prevent overcooking.

Vegetables can be enjoyed when cooked if good quality vegetables at the peak of freshness are chosen, the cooking method and other cooking conditions are maintained, and they are served immediately after cooking. For busy families, do not pre-cook the vegetables long before meal time but pre-prepare them by shredding or cutting and storing in a covered container. Cook by steaming, stir-frying or microwaving just in time for the meal.

Enjoy the flavours and the nutritive benefits of vegetables.

Rosalee M. Brown is a registered dietitian/nutritionist who operates Integrated Nutrition and Health Services; email: yourhealth@gleanerjm.com.