Shelf stable heat products must be safe, and be in no way hazardous to the health of the consumer. They should be nutritious while tasting good. The sterilization must be designed to fit those demands. First priority of course, is the product safety, but the retention of high quality is almost equally important.The sterilization value is calculated to determine the precise heating process to be applied (temperature and time) which is necessary to provide shelf stability to a food product inside a hermetically sealed container. A key factor in this, is the ability of the organisms in the products to withstand the heat. A basic requirement for the application of the clasical HTST sterilization (High Temperature Short Time) is the ability of the products to transfer the great heat input rapidly to the cold spot like UHT (Ultra High Temparature) sterilization technique applied to the milk.The term shelf-life denotes the time span for thermal processed food products to be stored at ambient temperatures without ill effect, or relevant quality loss.

Thermal processed foods are those products which being vegetable or animal in nature, and thus perishable, have been made shelf-stable by the combined application of three measures:

• The products is sealed into an airtight container
  
• Heat treatment is applied in order to destroy or inhibit all enzymes and microorganisms and their spores and toxins, since their continued growth, poliferation or activity would render the product unsuitable for human consumption.
  
• The heat treatment must be designed and controlled in such a manner as to provide the required sterility and inactivation and, at the same time, leave the product’s valuable nutritional values as well as its sensory characteristics undamaged to the highest possible extent. HTST food products have the following advantages;
• No “canning” taste or smell; the product has a natural flavor,
  
• No browning or yellowing; retention food’s natural colours;
  
• Very little or no fat and jel seperation;
  
• Homogenous appearance of finely textured products;
  
• Structure and consistency stay intact, meat chunks do not fall apart;
  
• Improved shelf stability and quarenteed sterilization effect;
  
• Longer storability because of less initial cooking damage