Ever since the invention of thermal processing as a method of preserving packaged foods by the Frenchman Nicolas Appert in the early 19th century, there has been a relentless search to reduce the amount of thermal damage to the quality of food products.
Today, however, the consumer demands much more than just safe and shelf stable food, including, primarily, higher quality food with greater convenience in the end use.
And food processors look for more energy-efficient, cost effective and high-speed processing technologies. Numerous methods exist for thermal processing of foods. Some of these techniques include the use of steam injection, stem infusion, tubular heat exchangers, shell and tube heat exchangers, plate heat exchangers, scraped surface heat exchangers extruders, ohmic heaters, infrared heaters, radio frequency heaters, microwave heaters and variations, combinations of these.
High temperature, short-time (HTST) techniques have primarily involved to minimize the severity of heat treatment and promote product quality.
Whatever the material and its shape or the food product it is necessary to apply a suitable process, i.e. given time at a specified temperature, to ensure that the products do not pose a public health problem, e.g. food poisoning.
Continuous aseptic processing, also called continues flow processing and packing further minimize the heat severity by quick heating and cooling of the food, prior to packaging, under aseptic conditions.
Product must be heated to a set temperature for a set time in order to achieve a commercially sterile product.
This profile, thermostable, microwavable packages have been developed for promoting faster heat transfer rates, which minimizes the heat damage to product quality while adding the convenience of package microwavability.
Rotary and continuous cooker for canned food have been based on product agitation during processing to accelerate the rate of heat transfer in order to promote better quality in processed foods.
Thermal processing of food
