With pressure steamers, the steam gradually builds within the compartment during the cooking process, allowing food to cook at temperatures up to 250°F. The pressurization of the cooking compartment can range between 5 and 15 PSI. Because the pressurization can build to intense heights, there is a risk of damaging or overcooking delicate products, as well as flavor transference between dissimilar items.
Pressure steamers are ideal for high volume batch steaming and are sometimes referred to as “lazy steam” because they cook food from the outside in. This is a great way to cook fresh, defrosted or loosely packed frozen products quickly; however, it’s best to avoid cooking frozen block products because the outside will become overcooked before the inside even thaws.
High pressure and low pressure steamers are available. Low pressure cookers operate at around 5 or 6 PSI and are ideal when cooking single items in large volume. They are popular in schools, institutions, large cafeterias, etc., and come equipped with gas or electric boilers built into the cabinet base. Some are also available with direct steam hookups, or with a steam coil heat exchanger.
High pressure steamers can build steam up to 15 PSI. Though they are capable of a higher output and faster cooing times, high pressure steamers are still not recommended for delicate foods or frozen block products.
In addition to high and low pressure steamers, there are also countertop and floor steamers and countertop models. Countertop steamers are available in gas, electric, or direct steam operation requiring no water or drain connection. They are manually filled with water and then drained through a petcock, which is then easily drained into a pitcher. Floor steamers are available for direct steam or outfitted for a boiler.