Industrial depuration may provide a means of removing domoic acid toxin from blue mussels (Mytilus edulis). Mussels containing up to 50 μg domoic acid∙g−1 were transported from a Prince Edward Island estuary into controlled laboratory conditions to test the effects of temperature, salinity, mussel size, and feeding upon depuration. Fifty percent of toxin was eliminated within 24 h. After 72 h, mussels were either clean or contained, on average, only residual levels of toxin (< 5 μg∙g−1), regardless of conditions. Exponential depuration curves were fitted to the domoic acid concentration data. To evaluate differences in rate of depuration under various conditions, statistical comparisons were made between slopes of the clearance curves. Rates of depuration were faster in small (45–55 mm) than in large mussels (60–70 mm) and more rapid at 11 than at 6 °C. There was no significant difference in depuration rate at 18‰ salinity as opposed to 28‰ or in starved versus fed mussels. Because of their relatively large digestive glands, meats of small mussels contained more toxin per unit weight than meats of large mussels. The bulk of domoic acid appeared to reside in the gut lumen. However, the presence of small amounts of domoic acid in intracellular compartments cannot be ruled out.

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The clinically important serotypes of Yersinia enterocolitica were shown to be highly heat sensitive, and none of the strains of serotypes 0:3; 0:5;27; 0:6,30; 0:8 and 0:9, ATCC 23715, and ATCC 27729 used in this study could survive high-temperature short-time pasteurization at 71.8°C for 18 s at 108 cell/ml. D62.8 was found to be 10.53 and 10.35 s in skim milk and whole milk, respectively. Destruction of the viable cells of Y. enterocolitica under freezing-thawing and constant freezing conditions at −20°C was more rapid in distilled water than in milk. Constant freezing at −20°C for 30 d had a negligible effect on the survival of Y. enterocolitica in milk.

The combined effect of nisin and moderate heat to increase the killing of Listeria monocytogenes in cans of "cold-pack" lobster was investigated. Adding nisin at a level of 25 mg/kg of can contents to the brine surrounding the lobster, in combination with a heat process giving internal can temperatures of 60 degrees C for 5 min and 65 degrees C for 2 min, resulted in decimal reductions of inoculated L. monocytogenes of 3 to 5 logs, whereas heat or nisin alone resulted in decimal reductions of 1 to 3 logs. Such a reduced heat process to that currently commercially used (65.5 degrees C for 13 to 18 min, depending on the can size) results in significant reduction in drained weight loss, thus allowing considerable cost savings to the lobster-processing industry.

1.[12SI]iodoinsulin-binding studies in the presence of a concentration range of bovine insulin were conducted to establish specific insulin-binding levels in skeletal muscle plasma membranes and isolated hepatocytes of rainbow trout (Salmo guirdnert) reared on control, high-protein or high-carbohydrate diets.2. Negative co-operativity was observed and receptor concentrations and apparent dissociation constants established for each preparation.3. No differences of specific binding attributed to diet were detected in skeletal muscle plasma membrane preparations; however, the receptor concentration of isolated hepatocytes from highcarbohydrate-reared trout was increased. This contrasted to comparable mammalian studies.