The New Complete Book of Food

 The New Complete Book of Food

Diets That May Restrict or Exclude This Food

Low-calcium, low-oxalate diet (for people who form calcium-oxalate kidney stones)

Low-sodium diet

Buying This Food

Look for: Fresh, crisp dark-green leaves that are free of dirt and debris.

Avoid: Yellowed leaves. These are aging leaves whose chlorophyll pigments have faded,

allowing the carotenoids underneath to show through. Wilted leaves or leaves that are limp

and brownish have lost vitamin C.

Storing This Food

Refrigerate loose leaves in a roomy plastic bag. If you bought the spinach already wrapped

in plastic, unwrap it and divide it up into smaller packages so the leaves are not crowded or

bent, then refrigerate.

Preparing This Food

Wash the spinach thoroughly under cool running water to remove all sand and debris. Dis-

card damaged or yellowed leaves. Trim the ribs and stems but don’t remove them entirely;

they are rich in food fiber. If you plan to use the spinach in a salad, refrigerate the damp

leaves to make them crisp.

What Happens When You Cook This Food

Chlorophyll, the pigment that makes green vegetables green, is sensitive to acids. When

you heat spinach, the chlorophyll in its leaves will react with acids in the vegetable or in

the cooking water, forming pheophytin, which is brown. The pheophytin turns cooked

spinach olive-drab or, if the spinach leaves contain a lot of yellow carotenes, bronze.

To keep cooked spinach green, you have to keep the chlorophyll from reacting with

acids. One way to do this is to cook the spinach in a lot of water (which dilutes the acids),

but this increases the loss of vitamin C. Another alternative is to cook the spinach with the

lid off the pot so the volatile acids can float off into the air. Or you can steam the spinach

quickly in very little water so that it retains its vitamin C and cooks before there is time

for the chlorophyll/acid reaction to occur.

Spinach also contains astringent tannins that react with metals to create dark pig-

ments. If you cook the leaves in an aluminum or iron pot, these pigments will discolor

the pots and the spinach. To keep the spinach from darkening, cook in an enameled or

glass pot.