Spray drying is a proven safe production method. 

To produce plasma proteins, for example, the liquid plasma is sprayed into a sterile chamber at 200 ºC or above. It is present in the chamber for a short period that is sufficient to ensure the fine spray droplets dry but not so long that the nutritional value is reduced. The temperature comes down to around 80–90 ºC where the dried powder is taken out and packed, still within sterile conditions. The high temperature and sterile packing contribute to the safety of the final product. 

Spray dried blood products have been used as feed ingredients for more that 20 years and there are no reports or suggestions that they ever have communicated a disease or toxin.

The risk of infection from OIE-list A diseases*, such as classical swine fever, being present and persisting in the blood products is regarded as negligible. All these diseases have clear clinical signs that are apparent to veterinary authorities. The pre-slaughter veterinary inspections conducted at the slaughterhouses where blood is collected are therefore an important safeguard. Additionally, combining the blood from many animals would greatly dilute potential contamination and spray drying at high temperature inactivates the viruses and bacteria that cause such diseases. 

Many analyses have been performed on plasma samples, haemoglobin and blood meal samples and have never shown detectable amounts of dioxins. This is to be expected as dioxins accumulate in fat and the fat content of these products is extremely low. In plasma proteins, for example, it is lower than 0.3%. 

*(OIE=Office International des Epizooties/The World organisation for animal health)