Each of these food businesses requires a variance from the health department EXCEPT when?

In the context of food safety regulations, certain practices are considered higher risk and thus require a variance from health departments to ensure they are handled safely. A variance is essentially a permission granted by health authorities that allows food establishments to implement alternative methods that don't strictly follow the established food safety regulations.

When it comes to serving undercooked steaks, this practice often does not require a variance when it's done in compliance with specific guidelines, such as meat being sourced from approved suppliers and the risks being adequately communicated to consumers. Many establishments are allowed to serve steaks cooked to a lower internal temperature as long as they inform patrons about the associated risks of consuming undercooked meat, particularly in relation to foodborne illnesses.

In contrast, the other options—packaging fresh, unpasteurized juice, smoking meats, or using additives to preserve food, and serving live shellfish—are practices recognized as necessitating a variance due to the increased risk factors involved with food safety. These methods could potentially lead to unsafe culinary practices or health risks if not managed properly, thus requiring formal approval from health authorities.