Green vegetables contain many vitamins, they also contain many parasites. Cooking is a way to kill the parasite but how to remain vitamins is what the housewife should know.
To eliminate worms' eggs, must rinse by water flowing each vegetable's stalks, hand strokes on the leaves, stalks. Cabbage leaves should be washed leaf-by-leaf without worry about leaves will re-roll, looking white but without any eggs. Should not buy more vegetables then clean and stored in the refrigerator. To keep vitamins, vegetables must be washed fully stalk and leaves and cut them only when cooking.
Studies showed that clean washed vegetables in the refrigerator are also perishable, while if leave them outside one day, the loss of vitamin C will be 26%; vitamin loss when washing is 1% but small cut and preserve longly will take 14%.
When boiling vegetables, you put a little salt into the water, boil the water with higher fire until hot boiled then ínẻt the vegetables into, put the cap tight. According to many studies, little salt could keep the green of the vegetables, cap covering only make 15% vitamin loss, cap opening will take 32% depreciation. Quickly stir once then pick vegetables out, nice taste if the vegetables are rather raw.
There are habits by housewives that put the vegetables into the pot while the cap is open with their opinion that the vegetables would be green. But the studies results point out that vegetables would lost 42% of vitamins if put into cold water, boil them when cap is opened would lost an additional 32%, so the vitamins almost lost but you still think that natural vitamins ate! Should not boil as vegetables carefully as the temperature will make vitamins lost. The "noble" vegetables like broccoli steamed and raw eating will be the best method. For best vegetables soup, also await the water boiled then cut and put vegetables into the pod.
For vegetables stir-fried, we found that the cooks stir fry quickly for a disc, then, serve hot. Why hot food? Because frying, boiling then eating only make about 15% vitamin lost, after 1 hour exposure will lose 25%, after 2 hours from 34-57% vitamin loss. If you are prepared, each subject waited for the husband, bring up the kitchen, then reheated they will make upto 90% vitamin loss.
LÊ THÚY TƯƠI Ph.D
Quoted from Tuổi Trẻ newspaper