[Polysaccharide additives in foods rich in proteins. i Sample preparation for estimation, especially in fresh cheese...

Published procedures for the isolation of polysaccharides from foods rich in proteins, especially fresh cheese, proved not very useful for the concentration in question (0,01--0.2%). We, instead, propose the following sample preparation: 1. Removal of lipids by an ethanol--ethyl ether--petrol ether mixture; 2. complete hydrolysis of proteins with pepsin, pronase E and a mixture of aminopeptidase M and prolidase; 3. separation of the polysaccharides from the low molecular substances and from enzyme residues by gel filtration on Biogel P-2; 4. concentration of the polysaccharides containing fraction by freeze drying, ultrafiltration or evaporation. --The method was tested with quarg and double cream fresh cheese, it can, however, be adopted to use in other products.