We wholeheartedly agree with Dr. Sacks that an important part of the prevention of foodborne botulism is to provide adequate "refrigerate after opening" label statements on foods that require refrigeration. With the increasing number of "new-generation," minimally processed foods, abuse of the temperature of such products by distributors, retailers, and consumers has become a public health concern. The U.S. Food and Drug Administration is currently drafting a guidance document for the food industry to address this issue. The document will respond to recommendations of the National Advisory Committee on Microbiological Criteria for Foods, the National Food Processors Association, the Association of Food and Drug Officials, and the Centers for Disease Control and Prevention and will provide guidance on various aspects of product labels, including the size and location of the print.

The adequacy of product label statements to prevent botulism outbreaks has long been questioned. A large outbreak of botulism in 1985 [1] associated with garlic in oil led to arguments for altering the product's formulation in addition to improving food labels. "Intrinsic barriers" to botulinum toxin production (such as acidifying agents) were not required until after a second outbreak caused by garlic in oil was recognized in 1989 [2]. Whether to wait until another outbreak caused by cheese sauce occurs before attempting to improve the safety of the product is a reasonable subject for debate. However, the debate must consider our inoculation studies that have shown that the cheese sauce is an excellent culture medium for Clostridium botulinum and that the microenvironment beneath the surface of the cheese sauce appears to be sufficiently anaerobic to support botulinal growth and toxin production. If the rarity of botulism is analogous to being struck by lightning, mishandling this product is certainly analogous to gripping a lightning rod in a thunderstorm. Unfortunately, it is difficult for product labels to communicate to consumers the potential hazards of mishandling certain food products.

The botulism hazard in cheeses is controlled by the interaction of several factors, including the amount of salt, moisture, phosphate salt emulsifiers, and pH. Manipulating any one of these factors might be adequate to decrease the risk from this product if it is left unrefrigerated. Additional studies are needed to determine the method of altering this product that is the most cost-effective and would be acceptable to both producers and consumers.