What is the Still Retorts?
Still Retorts are used in canning plants for heating foods in glass containers or different sizes of cans. These retorts are usually cylindrical in shape and may be oriented vertically or horizontally with a heavy lid or door on top or at one end. Containers are loaded in layers into perforated retort baskets or crates. This may be done manually or by machine. Filled crates are placed into the retorts, the lid is closed and steam is introduced. Water with steam injection is used for glass containers since they cannot handle the heat stress. An overriding air pressure maintains enough pressure so that the water does not "boil" at temperatures greater than 100°C. Temperature in a retort is regulated by means of a steam automatic valve. At the end of the "cook" cycle, the retort is showered/flooded with cold water (metal cans) or injected with cold water just below the surface of the hot water (glass jars). The containers are removed once they are cooled. The sequence of operations employed in canning are highlighted in the next section. This will give you a good idea as to what canning as a procedure involves.