Microstructure of fermented sausage.

A protein matrix is necessary for the desired texture of fermented sausages suitable for slicing. The formation of this network is predominantly induced by myosin and actin proteins. A change in the structure of native muscle proteins results from different technological processes such as chopping, salting, and fermentation. During chopping with simultaneous release of meat proteins, the salt brings about a change in the original structure of proteins by swelling and partial solution of myofibrils. The dissolved proteins are transformed into a thin fluid colloidal transition state, the so-called 'sol-state' with unstable coagulation bonds. During sausage ripening, as a result of denaturation by lactic-acid and due to gradual loss of water (drying), the unstable bonds are replaced by condensation bonds, and thus the sol-state is converted into the 'gel-state'. Both gel formation (condensation structure) and water evaporation (syneresis) result in the development of a matrix in fermented sausage and, consequently, in the texture of the sliceable product.

[Studies of acid-soluble antigens in several strains of the genus Bacillus for orienting purposes (author's transl)]. / Orientierende Untersuchungen über säurelösliche Antigene an verschiedenen Stämmen der Gattung Bazillus.

By acid hydrolysis (0.2 n HCl) it was possible to obtain extracts from nonsporulated cells of different strains of 5 species of the genus Bacillus which were composed mainly or solely of species-specific antigens. This was the result of experiments using the immunodiffusion technique after having prepared antisera from rabbits with the aid of HCl extracts. Cross-reacting antibodies were adsorbed easily. The species-specific reacting antisera revealed the existence of group- or strain-specific antigens. Therefore HCl extracts could become helpful in serotyping strains which belong to the taxa of the genus Bacillus.

[Studies of the purification of the exotoxin of Bacillus cereus (author's transl)]. / Versuche zur Reinigung der Ektotoxine des Bacillus cereus.

The exotoxins of Bacillus cereus show haemolytic, lethal, Phospholipase-C- and enterotoxigenic activities. The enterotoxigenic activity is regarded to be the factor which causes food poisoning in man. Efforts to purify the B. cereus exotoxins by precipitation with ammonium sulphate and subsequent chromatography on Sephadex-G-75 and Biogel-P-60 columns were partially successfull. Haemolysin and Phospholipase-C could be separated by gel-chromatography, they demonstrated partial identity on gel-diffusion agar. The lethal and enterotoxigenic activities could not be separated from the other toxins and remained heterogenous. No immunological relationship was found between Clostridium Type A alpha toxin and enterotoxin and the exotoxins of B. cereus.

[Detection of Bacillus cereus-toxins (author's transl)]. / Nachweis von Bacillus cereus-Toxinen.

During the logarithmic state of growth, B. cereus produced extracellular toxins, which could be precipitated by ammoniumsulphate. The toxins were not dialysable. 9 strains of B. cereus were tested and showed lethal, hemolytic, and phospholipase-C-reactions. The lethal toxin injected i.v., killed mice within 20 minutes. An intradermal injection of the 9 toxin-precipitates in rabbits produced skin reactions, which could be neutralized by a specific antiserum against the B. cereus strain B-4ac. Relatively high doses (50 mg/ml) of the toxin caused fluid accumulation after injection in ligated loops of rabbit gut (Tab). The hemolysin of the tested B. cereus strains was found to be thermolabile. The phospholipase-C activity withstood the temperature of 55 degrees C for a period of 10 minutes. The prepared specific antiserum, which inhibited the phsopholipase-C activity totally, had no effect on the hemolysis. Intradermal and enteropathogenic activities point to the presence of an enterotoxin. For detection of the enterotoxin, the skin-test in guinea pigs or rabbits seems to be most appropriate.