Frozen Yogurt

With always having egg whites in the freezer and not really keen on meringues I found this great recipe for frozen yogurt. I make my own yogurt so that makes this even nicer.
4 servings
Ingredients 2 cups Yogurt cheese ½ cup Sugar 1 tablespoon Vanilla 4 Egg whites 1 cup Fresh strawberries or mixed berries, roughly chopped	Preparation One cup of yogurt makes about 1/2 cup of yogurt cheese. But scientists don't know how much calcium is lost straining off the whey, so 1/2 cup yogurt cheese could contain nearly a cup serving's worth of calcium. The calcium in this recipe is figured according to this formula. To strain, place a colander lined with cheesecloth in a bowl. If the colander has legs, it can stand right in the bowl. If it doesn't, rest it on the bowl edge so there is room for the whey to drain off. Weight the yogurt down with empty glass jars. Straining takes at least six hours. Don't stop until the remaining cheese is about the consistency of cream cheese. Mix yogurt cheese, sugar and vanilla. Whip egg whites until stiff, fold into yogurt cheese-sugar mix. Fold fruit into mixture. For best results let the mix stand overmight in refrigerator. Freeze according to ice cream maker instructions. Note: If you don't have an ice cream maker just partially freeze, take out break up ice crystals with a fork and beat lightly and refreeze.