starch and other complex carbohydrates. Raw bananas are richer in potassium than cooked
bananas; heating depletes potassium.
Diets That May Restrict or Exclude This Food
Buying This Food
Look for: Bananas that will be good when you plan to eat them. Bananas with brown
specks on the skin are ripe enough to eat immediately. Bananas with creamy yellow skin
will be ready in a day or two. Bananas with mostly yellow skin and a touch of green at either
end can be ripened at home and used in two or three days.
Avoid: Overripe bananas whose skin has turned brown or split open. A grayish yellow skin
means that the fruit has been damaged by cold storage. Bananas with soft spots under the
skin may be rotten.
Storing This Food
Store bananas that aren’t fully ripe at room temperature for a day or two. Like avocados,
bananas are picked green, shipped hard to protect them from damage en route and then
sprayed with ethylene gas to ripen them quickly. Untreated bananas release ethylene natu-
rally to ripen the fruit and turn its starches to sugar, but natural ripening takes time. Artificial
ripening happens so quickly that there is no time for the starches to turn into sugar. The
bananas look ripe but they may taste bland and starchy. A few days at room temperature
will give the starches a chance to change into sugars.
Store ripe bananas in the refrigerator. The cold air will slow (but not stop) the natural
enzyme action that ripens and eventually rots the fruit if you leave it at room temperature.
Cold storage will darken the banana’s skin, since the chill damages cells in the peel and
releases polyphenoloxidase, an enzyme that converts phenols in the banana peel to dark
brown compounds, but the fruit inside will remain pale and tasty for several days.
Preparing This Food
Do not slice or peel bananas until you are ready to use them. When you cut into the fruit,
you tear its cell walls, releasing polyphenoloxidase, an enzyme that hastens the oxidation of
phenols in the banana, producing brown pigments that darken the fruit. (Chilling a banana
produces the same reaction because the cold damages cells in the banana peel.) You can
slow the browning (but not stop it completely) by dipping raw sliced or peeled bananas into
a solution of lemon juice or vinegar and water or by mixing the slices with citrus fruits in
a fruit salad. Overripe, discolored bananas can be used in baking, where the color doesn’t
matter and their intense sweetness is an asset.
Bananas