there are hundreds of tomatillo varities, there are two main types:
green and purple. Purple tomatillos, Physalis ixocarpa, are a member of
the nightshade family, Solanaceae. They are the fruit of a bushy perennial sprawling vine that grows low to the ground. Description
Purple tomatillos are similar in shape to a tomato, though rounder with an average diameter of generally only two inches at maturity. The Purple tomatillo is encased in a paper thin heart-shaped husk which is green in coloring when young. The husk will eventually split and become burlap toned as the fruit matures. The fruit itself, when young develops a lime green color that fades and becomes violet purple with white markings at each end as it ages. A mature tomatillo will have filled its husk, have a firm, waxy exterior and a moist, cottony seed-bearing flesh. Though, the fruit resemble the look of a tomato, their flavorings are starkly different. As tomatoes sweeten with maturity, the Purple tomatillo is fruitier and truly sweet-tart with citrus flavors of lemon and lime and sub-acid flavors of plum and pear. Purple tomatillos are less tart than their green counterpart and cooking them will enhance their flavor while also imparting a greater depth of sweetness.Nutritional Value
The presence of Anthocyanins, responsible for the coloring of the purple tomatillo, has led to medical studies discovering that the Purple tomatillo is a good source of antioxidants and cancer fighting compounds.Cullinary use
Tomatillos are a staple in Mexican cuisine and cooking 101 with tomatillos equals salsa. The tomatillo's role in the kitchen does not end with salsa, though. Purple tomatillos can be substituted for recipes calling for green tomatillos, though they are considered more exceptional for their coloring and their sweeter flavor. Purple tomatillos lend themselves to many different cooking methods. They can be stewed, fire roasted, grilled, broiled, blanched, puréed, chopped fresh and utilized as an ingredient in applications both hot and cold. Traditional and authentic accompanying ingredients include corn, tomatoes, garlic, chiles, avocado, red, white and black beans, tortillas, fresh and aged cheeses. Tomatillos can heighten the flavor of pork, chicken and seafood in Latin recipes as well as seasonal and regional recipes throughout the months of late Summer and Fall. Herbal companions include cilantro, basil, mint, epazote, cumin and oregano. As Purple tomatoes deliver more sweetness, they can also be utilized to make marmalades, jams and preserves. Once tomatillos are removed front their husk, they should be washed to remove the slightly sticky film from the skin's surface. Fresh tomatillos in their husks will stay fresh refrigerated in a paper bag for up to two weeks. Cooked tomatillos can also be preserved by canning them or freezing them for later use.
Also see Tomatillos
Read More At Wikipedia