Modern blood plasma volume expanders consist of water‐soluble polysaccharides that are compatible with the human body. They are more effective for the treatment of intravasal volume deficiency compared to synthetic polymers. These colloidal blood plasma volume expanders, for example pullulan, dextran or hydroxyethyl starch (HES) are used in blood isotonic electrolyte solutions. HES has the lowest tendency to remain in the liver or other organs of the human body in comparison to other expanders.The knowledge of the molar mass and coil dimensions as well as their distribution are essential, since products of low molar masses do not have the desired effect and parts of large molar masses can lead to an anaphylactic shock. Injection of HES enhances the microcirculation and leads to a better oxygen transport into the tissue and the muscle. Because of this, HES was identified as a doping agent in 02/2002. In addition to this it will be shown that starch acetates have an even better physiological compatibility and are an interesting alternative to HES. We will present investigations on the shelf life of a new acetyl starch, which may be an alternative to the blood plasma expanders used to date.