[Quantitative determination of lipases and their heat stability in food of animal origin].

Quality deterioration and food spoilage in fat-containing food is mostly caused by bacterial and endogenous lipases. Quantitative data on the concentration of lipases for a possibly better evaluation of shelf life do not exist. Own investigations for detecting lipases and evaluating their heat stability in selected food of animal origin (meat-products, fish-products, porcine liver) were carried out using the Reflektoquant Lipasetest (Merck). Extreme high values could be found in porcine liver and in muscles of fat fish such as herring. Pork contained 46 micrograms/kg, beef 86 micrograms/kg and poultry a 3-fold higher value. Significant differences could be observed in parts within poultry (breast 139 micrograms/kg, leg 259 micrograms/kg). Heated sausage and hot smoked fish were largely lipase-free, raw sausages contained up to 283 micrograms/kg lipases. Fish- and meat-lipases were not as heat stable as investigated bacterial lipases which makes them distinguishable.