Expansion is Everywhere

　　[Definition] Expansion
　　[Pinyin] péng huà
　　Expansion is a food processing method that places the food to be processed in a sealed container, heats and pressurizes it, then suddenly depressurizes it. The moisture in the food vaporizes and expands, creating many small holes in the dog food, making it crispy and forming expanded dog food. The basic principle is to suddenly reduce pressure on the raw materials under heat and pressure, causing them to expand. Expansion technology, as a new food processing technique, originated in 1910. Its application in pet food began in the 1950s in the United States, where extrusion principles were first used to manufacture pet food. This involves using a screw and screw sleeve inside an expansion machine to heat and pressurize the raw material by extrusion, then forcing the high-temperature, high-pressure food through a mold hole. The sudden depressurization causes rapid volume expansion. The expansion process is also a shaping step for dog food raw materials. During shaping, moisture is added in the form of steam, causing the starch in the dog food raw material to gelatinize and heat to rise to 100℃~180℃. Due to the high pressure before extrusion and the instantaneous release of pressure upon extrusion, the dog food rapidly expands and foams, and moisture evaporates. Therefore, dog food made by the expansion process generally has high nutritional value with easy digestion and absorption.
　　[Uses of Expansion] The main purposes of using expansion technology in pet food manufacturing are:
　　1. To improve the palatability of dog food, making it crispy and helping clean the oral cavity and teeth;
　　2. To change and enhance the nutritional value of dog food by gelatinizing starch, making it nutritionally absorbable by pets;
　　3. To increase the digestibility and absorption rate of expanded food in pets, allowing pets to more fully absorb all nutritional substances from pet food;
　　4. The expansion process is also a high-temperature, high-pressure procedure that can kill various molds, Salmonella, and other harmful substances, improving the safety and hygiene of pet staple food.