Which method of food preservation commonly uses heat?

Canning is a method of food preservation that commonly uses heat to enhance shelf life and safety. This process involves sealing food in cans or jars and then heating them to destroy microorganisms and inactivate enzymes that may cause spoilage. The heat treatment also creates a vacuum seal, which further protects the food from contamination after sealing.

In contrast, other methods such as freezing rely on low temperatures to inhibit microbial growth, while salting draws moisture out of food, effectively creating an environment that discourages microbial activity. Dehydration focuses on removing moisture from food, thereby reducing the potential for spoilage, but it does not involve heat in the same way canning does.

Thus, canning stands out as the method that specifically incorporates heat for preservation, making it the correct answer.