Disgruntled consumers who maintain the vanilla ice cream they purchased did not contain real vanilla do not have a case against the product’s manufacturer, a federal judge held.In a written opinion, U.S. District Judge Elaine E. Bucklo of the Northern District of Illinois dismissed a proposed class-action lawsuit accusing Prairie Farms Dairy Inc. of violating consumer fraud laws by including purportedly deceptive statements on the labeling of its Premium Vanilla ice cream.The plaintiffs argue that the ice cream&rsquo …