Physicochemical changes induced in carp (Cyprinus carpio) fillets by high pressure processing at low temperature

Raw carp fillets (Cyprinus carpio) were vacuum packed and pressurized at 100, 140, 180 and 200 MPa at 4 °C for 15 and 20 min, and then monitored for changes in the lipid fraction, color and electrophoretic profiles. The values of thiobarbituric acid (TBA) reactive substances in the samples increased with pressure and pressurization time. Similar results were obtained for free fatty acids (FFA) levels formed as a result of pressure treatment. The CIE color values, i.e., L⁎ (lightness), a⁎ (redness) and b⁎ (yellowness) of the carp fish fillets also increased with pressure and pressurization time, and the results obtained attest to the importance of establishing treatment conditions for various fish species when processing these food products in order to minimize changes in their appearance and flavor characteristics.Industrial relevanceHigh pressure processing is finding increasing use in the food industry because of its relative advantages versus other food processing methods in eliciting minimal changes in the flavor and nutritional qualities of the final product. High pressure treatment is able to achieve this via its effects on the two causative agents of food spoilage, namely autolysis as well as microbial growth and metabolism. High pressure processing has been used commercially to produce food products such as raw oysters, guacamole, and ham and fruit juices in the US; and to produce jams, jellies, fish and meat products, salad dressing, ham, fruit juices and yogurt in Europe and Japan. However, in spite of the notion that high pressure processing results in minimal changes in food products, it is also common knowledge that the technology induces important changes in the texture and appearance of raw fish would be influenced by temperature at which the pressurize treatment was conducted. This paper illustrates the changes induced in raw carp flesh by pressurization at different temperatures.