A retort is a piece of equipment used for ______________.

A retort is specialized equipment primarily used in the canning process. It functions as a high-pressure vessel that allows for the sterilization of canned foods at elevated temperatures. This process eliminates harmful microorganisms and enzymes that can spoil food, ensuring its safety and extending shelf life. The high temperatures and pressures help to create a vacuum seal that prevents contamination once the cans are sealed.

In contrast, the other options pertain to different cooking and food preservation methods. Frying involves cooking food in hot oil; drying removes moisture from food to inhibit microbial growth; and baking is the method of cooking food using dry heat in an oven. Each of these methods has distinct principles and equipment associated with them, which is why they do not relate to the primary function of a retort.