RSW Brine Freezing Onboard Fishing Boats and Tenders
Marine refrigeration is essential to deliver top-quality product and receive top dollar from today’s discerning seafood buyers. RSW brine systems allow freedom from the need and cost of ice while providing the ability to fish longer and catch more product. The catch is chilled quickly and uniformly and the ideal temperature is maintained over the length of the voyage. RSW eliminates the slow and fatiguing work of shoveling ice and layering fish, plus the bulk and weight of the ice and the need to travel to get it are gone – conserving fuel.
A brine freezing system is similar to those used for RSW. Salt is added to the water until it becomes a near-saturated brine solution, reducing the temperature at which it freezes to below 0 degrees Fahrenheit. The salt brine solution is then refrigerated down to around 0 degrees F and the product is either immersed in or sprayed with the low temperature solution – which freezes the product, but not the brine solution. Getting the salinity of the solution is important in order to deliver quality product. Typical freezing capacities range from 7.5-ton to 60 HP. The unit can be diesel-drive, electric or hydraulic. (Look at A Ton of Refrigeration for more info.)
Brine Freezing in Processing Plants
In seafood processing plants, brine freezing is often the best way to handle certain products – like crab and shrimp – since moisture is retained and the delicate appendages tend to remain intact. After the crab, for instance, is cooked, they are usually dropped into water cooled with an RSW system to remove the heat and then to a brine tank to freeze. Sockeye salmon and other fish are also products where brine freezing is used to deliver moist, attractive-looking product to consumers.