Clean the fish properly before packaging them in vacuum sealed packages. The amount of fish packaged should not be so much that the vacuum seal is compromised. Pack the fish tightly into the packaging and use a professional grade vacuum sealer to close the packages.
Place the fish in pre-frozen refrigeration containers. These containers should be at a temperature of at least 64 degrees Fahrenheit if not colder when the fish is placed inside. Seal the containers tightly once the fish have been placed inside.
Maintain a constant and cold environmental temperature so that the fish do not spoil. Also, maintain 90 to 95 per cent variable relative humidity in the immediate vicinity of the fish to prevent spoilage. Measure the temperature and variable humidity with a hygrometer and air thermometer. Check the readings frequently throughout transport or store the containers in an area where relative humidity and air temperature will not fluctuate.
Inspect the packages upon arrival for any signs of spoilage. Generally, the deep freeze was successful if the fish thaws during transport and is left at warmer temperatures. Packages that have become unfrozen will have frost or ice crystals indicating that they defrosted and they froze again. This could indicate a potentially hazardous environment where bacteria cultivated and spoiled the fish, even if it refroze.
