If you don't plan to eat your fresh fruit or vegetables for a few days, you're better off buying flash-frozen ones. The vitamin content of good frozen green beans will be higher than those fresh ones you've kept in your refrigerator for a week. Store frozen meat at 0 degrees F or lower immediately after purchase to prevent loss of quality and bacterial growth. Outer green leaves of letture, though coarser than inner ones, have higher calcium, iron, and vitamin A content. Don't thaw your frozen vegetables before cooking.
Broccoli leaves have a higher vitamin A value than the flower buds or stalks.
There are more vitamins in converted and parboiled rice than in polished rice, and brown rice is more nutritious than white. Frozen foods that you can boil in their bags offer more vitamins than the ordinary kind, and all frozen foods are preferable to canned ones. Cooking in copper pots can destroy vitamin C, folic acid, and vitamin E. Stainless steel, glass, and enamel are the best utensils for retaining nutrients while cooking. The shortest cooking time and the smallest amount of water are the least destructive to nutrients. Milk in glass containers can lose riboflavin, as well vitamins A and D, unless kept out of the light.