Portabella Mushrooms are low in sodium, and very low in saturated fat and cholesterol. They're also a good source of Thiamin, Vitamin B6, Iron, Magnesium and Zinc, and a great source of Dietary Fiber, Riboflavin, Niacin, Folate, Pantothenic Acid, Phosphor
To store mushrooms, keep them unwashed, dry, cool and dark.
Store mushrooms in a brown paper bag, or in a Tupperware type container on a paper towel in the refrigerator. Do not store mushrooms in plastic bags!
To clean mushrooms, wipe them with a damp cloth or soft vegetable brush. Because of their porous nature, mushrooms should not be washed in water, as they will absorb water like a sponge, losing nutrients, flavor and changing texture.
Three thousand years ago, mushrooms were a delicacy of the Pharaohs in Egypt, who considered them too delicate for common people to eat. They were favored in ancient Rome as a "food of the gods."