Although the most common zucchini varieties are dark green and somewhat resemble a cucumber in appearance, there are also light green, striped, and yellow varieties. Other shapes and sizes of zucchini also exist, such as a round ball shape and a chicken egg shape. Zucchinis are low in calories and high in folate, potassium, and beta-carotene. They also provide fiber. A fresh zucchini is firm to the touch all over, and any softness indicates an old zucchini that is no longer good. Fresh zucchini can be stored in the refrigerator for about five days. It is best to dry them well with a towel and then wrap each one in a paper towel before putting them in a snug plastic bag in the refrigerator. This dry environment prevents spots from forming on the zucchini skin. The skin is not removed before eating. The mild flavor of zucchini allows it to be added to many different kinds of dishes.