The Method of Carbon-Dioxide Recovery in Fish-Processing Industry

There is a growing demand for rapid cooling in modern food industry. Traditional methods of fish cooling involve cold air, cold liquid, and ice. These methods have a number of disadvantages. For instance, they may have a negative effect on the appearance of the product, require a longer cooling time, or make fish absorb extra moisture. As a result, the quality of the product and its shelf life decrease, which results in demand contraction. Carbon dioxide is becoming increasingly popular in closed refrigeration systems. It is one of the most promising refrigerants, since traditional refrigeration technologies for fish cooling have a number of serious drawbacks. The paper introduces a utilization method for carbon dioxide obtained at alcohol processing plants. The authors analyzed the prospects of using carbon dioxide in combination with a binary mixture for cooling trout. A series of experiments proved the technological advantages of this technology. The paper features heat transfer in roundfish during cooling with water ice, a mixture of water ice and snow-like carbon dioxide, and snow-like CO2 in pure form. The obtained results show the effect of the concentration of snow-like carbon dioxide in water ice on the intensity of the cooling process. A higher intensity of the cooling process reduced the cooling time and the amount of water ice. The study of quality indicators of trout proved that the environment of water ice and carbon dioxide increased its shelf life by several times. The paper contains temperature graphs and duration curves at different concentrations of CO2.