12. 19, 2019
The traditional pelleting process includes pelleting, cooling, crumbling and screening. This process is usually used to produce livestock and poultry feed or other low energy feed, usually the product is relatively loose. Nowadays, the pelleting process in some factories is much more complicated, including the following processing steps:
The conditioning promotes the starch gelatinization and protein denaturation, which not only improves the nutritional value of the feed, but also improves the granulation performance of the material, thus improving the processing quality of the pellet product. Water, temperature and time are the three factors of starch gelatinization. The conditioning makes the raw material contacting the steam. With the enhancement of conditioning conditions, starch gelatinization increased. After gelatinization, starch changed from original powder to gelatinization. Ungelatinized raw starch, like the sand, has a great resistance when passing through the die hole, which reduces the pressing yield, consumes more energy for granulation, and affects the working life of the die. After the product into pellets, raw starch and other components do not adhere to each other, resulting in loose pellets and high damage rate. After tempering, starch is fully gelatinized, gelatinized starch plays a lubricating role in the die hole, when forming pellets, the gel fills in the gap between components, and binds each component together, making the product compact and solid. The main function of post-curing is to improve the water resistance of fish and shrimp feed, and to do the hydro-thermal treatment to particle surface through steam, so as to change the surface structure of the pellets and prevent the pellets from breaking up in water. To do the post-curing treatment for common feed pellet, the steam treatment time is 0, 30, 60 and 90s, and the static water resistance time is respectively 0.2, 6, 16 and 18h. The effect is very significant.
The introduction of extruding, conditioning and post-curing has a positive effect on improving the quality of pellet feed. However, heat treatment has been adopted in all these three treatments. Some of the heat-sensitive nutrients contained in the feed break down when heated. Vitamin C, for example, is largely inactivated during processing. In addition, some high energy feed contains more grease. If the grease is added before pelleting, it will lead the pellet loose and fragile. The coating technology is an effective way to solve this problem. FDSP (Liangyou stock) has many years of experience in feed mill construction and old plants transformation, can customize according to the actual requirements of customers, to solve all kinds of professional problems for you. Welcome to consult: firstname.lastname@example.org