The serum of the Newborn Calf category is obtained from 3 to 10-day old calves. In comparison, Calf Serum is obtained from animals that are not more than 12 months old. Newborn Calf Serum and Calf Serum contain more immunoglobulins than Fetal Bovine Serum and have an increased protein content. They are a cost-effective alternative to Fetal Bovine Serum. Heat inactivation will inactivate the complement system, antibodies, and other active enzymes. It has to be done in a carefully controlled process to avoid damaging the cell growth-promoting properties of the serum and reducing the formation of unwanted precipitates. The process involves heating the serum in a shaking water bath at exactly +56 °C for 30 minutes. The shaking helps to avoid the formation of protein and other forms of precipitates. After 30 minutes the serum is cooled to room temperature as quickly as possible to avoid excessive exposure to heat which can damage e.g. growth factors and vitamins.