Casing manufacturing at Nitta Casings starts with the corium layer. The corium layer which lies between the grain leather (hide) and the flesh and fat layer is rich in protein. Nitta works closely with only a select few suppliers to ensure that this collagen rich material adheres to the most stringent quality requirements.
The collagen layer is then reduced to its fibrillar state in our factory by grinding and then conditioning according to Nitta’s exclusive process. At this point, the collagen is mixed with specific, approved, U.S.D.A. and F.D.A. food grade ingredients that are chosen to impart key characteristics to the product benefiting both sausage manufacturers and consumers. The resulting “gel” is then homogenized to increase the uniformity of the casing size, diameter and wall thickness upon extrusion. The collagen gel is then extruded in a continuous tube. Nitta’s extrusion process aligns the collagen fibrils so that the casings can stuff, twist and link, assuring efficient production of sausage at high performance levels. The extrusion process that Nitta engineers have developed also permits precise size control of the collagen tube. This assures uniform size, weight and lengths for the finished sausage — key benefits in the competitive world of sausage manufacturing.
Once extruded, the casing tube passes through water and treatment baths to improve its pliability and machining. Then it moves through a drying tunnel that carefully controls the temperature and humidity. The dry casing is now ready to be “shirred” or pleated into “slugs” of easily handled and easily used lengths of collagen.
These shirred collagen slugs are then boxed with a further check on moisture content before being hermetically sealed and put into outer cartons for storage.
The specifications for every stage of the Nitta process have been refined over the years to allow us to produce casings for a wide range of different applications. Each casing, however, is designed to provide the sausage manufacturer the highest levels of productivity and efficiency. This is the Nitta difference!