Chow Line: Try kiwi for burst of nutrients, color (for 7/13/08)

July 3, 2008

I like kiwi in fruit salads I enjoy at potlucks and other gatherings, but I've never purchased one myself. Any tips on selecting and preparing it?

Good for you. Kiwi is chock full of nutrients and, thanks to chlorophyll, its bright green interior color adds spark to fruit salads and other foods.

Ounce for ounce, kiwi has more vitamin C than an orange -- one medium-size peeled fruit (about 2.5 ounces) has less than 50 calories and contains 70 milligrams of vitamin C, nearly what you need for an entire day. (The recommendation is 75 milligrams of vitamin C per day for women and 90 milligrams a day for men.)

Kiwi also a good source of vitamin K and offers a respectable amount of vitamin E, potassium and fiber. Plus, it contains a variety of flavonoids and carotenoids that act as antioxidants, offering the potential for additional health benefits.

Selecting ripe kiwi isn't difficult -- but you can't go by color. The tan skin looks the same whether it's ripe or not. All you have to do is squeeze the fruit gently; ripe fruit will yield slightly but won't be soft. You can ripen firm kiwi by storing it at room temperature until it softens -- maybe three to five days. You can speed up the process by placing kiwi in a brown paper bag with an apple. The apple gives off ethylene, which helps kiwi ripen.

According to the U.S. Department of Agriculture's publication "How to Buy Fresh Fruits," some kiwis may appear be "water-stained." Don't worry about it -- it's a normal coloration and does not affect the fruit's quality. However, avoid kiwis that are excessively soft or that have signs of shriveling or mold, all of which indicate spoilage.

Just before cutting, rinse kiwi under running water. Most people peel kiwi with a paring knife, but the fiber-rich skin is edible. If you want to try it, gently rub the excess peach-like fuzz off the skin with a clean cloth while rinsing.

Most experts recommend adding kiwi to a fruit salad or other foods at the last minute. That's because kiwi contains an enzyme, actinidin, that digests protein. Although there's not much protein in most fruit you might put in a fruit salad, there's some, and actinidin can cause the other fruit to soften.

The same enzyme also prevents gelatin from setting. If you want to include kiwi in your favorite gelatin dessert, cook it for a few minutes first to inactivate the enzyme. Some suggest pureeing kiwi and using it as a meat tenderizer -- in 30 minutes, the enzymes can tenderize meat or poultry (and it won't end up tasting like kiwi).

Chow Line is a service of Ohio State University Extension and the Ohio Agricultural Research and Development Center. Send questions to Chow Line, c/o Martha Filipic, 2021 Coffey Road, Columbus, OH, 43210-1044, or filipic.3@cfaes.osu.edu.

Editor: This column was reviewed by Lydia Medeiros, nutrition specialist with Ohio State University Extension and the Ohio Agricultural Research and Development Center; and professor of human nutrition in the College of Education and Human Ecology.

 

Author(s): 
Martha Filipic
Source(s): 
Lydia Medeiros