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View the documentMaintaining the nutritional value of vegetables: Food preparation tips

Maintaining the nutritional value of vegetables: Food preparation tips

The nutritional value in any food starts to deteriorate at the very moment of harvesting and continues with each stage of storage and preparation, resulting in additional vitamin losses Here are some preparation tips to help retain the nutritive value of vegetables

Trimming

Vegetables must be trimmed sparingly to prevent the significant waste of vitamins and minerals, as these nutrients are generally present in higher concentrations in the outer layers of vegetables, seeds, roots and fruit For instance, with the peeling of potatoes, 12-35% of the vitamin C may be discarded Peeling of carrots may cause a marked waste of vitamins B1, B2 and nicotinic acid


Trimming

Washing

If the food has not been chopped or sliced too finely, the washing of vegetables for short periods does not adversely affect nutrient losses, so wash vegetables before they are chopped


Washing

Cooking

Boil vegetables in as little water as possible to minimize losses in vitamins and minerals Serve the cooking liquids with the vegetables or make them into sauces, gravies or soups Cook vegetables until just tender and serve immediately.


Cooking

Boiling Guide for Fresh Vegetables

Vegetable

Boiling time

Vegetables

Boiling time


(minutes)


(minutes)

Asparagus:


Celery, cut up

15 to 18

Whole

10 to 20

Chard

10 to 20

Tips

5 to 15

Collards

10 to 20

Beans:


Corn, on cob

5 to 15

Lima

25 to 30

Kale

10 to 15

Snap, l-inch pieces

12 to 16

Ladyfinger

10 to 15

Beets:


Onions

15 to 30

Young, whole

30 to 45

Parsnips:


Older, whole

45 to 90

Whole

20 to 40

Sliced or diced

15 to 25

Quartered

8 to 15

Beet greens, young

5 to 15

Peas

12 to 16

Broccoli, heavy stalks,


Potatoes:


split

10 to 15

Whole, medium-sized

25 to 40

Brussels sprouts

15 to 20

Quartered

20 to 25

Cabbage:


Diced

10 to 15

Shredded

3 to 10

Rutabagas, pared, cut up

20 to 30

Quartered

10 to 15

Spinach

8 to 10

Carrots:


Squash

8 to 15

Young, whole

15 to 20

Sweet potatoes, whole

35 to 55

Older, whole

20 to 30

Tomatoes, cut-up

7 to 15

Sliced or diced

10 to 20

Turnips:


Cauliflower


Cut-up

10 to 20

Separated

8 to 15

Whole

20 to 30

Whole

15 to 25

Turnip greens

10 to 30

Reference:

Consumer and Food Economics Research Division Agricultural Research Service. 1971. Family
Fare: A Guide to Good Nutrition. USDA, Washington, D.C.