Exploring solution composition and vacuum pulse effects in the osmotic processing of sole (Paralichthys sp.) fillets

The study investigates the osmotic dehydration (OD) of sole fillets and its mass transfer kinetics. Brine (S10), brine+sucrose (S10Az), and brine+sucrose+acetic acid (S10AA) solutions were used, with treatments conducted under atmospheric pressure (control) and with vacuum impregnation pulses (VI) for 7 hours. A positive mass change was observed over time in S10 and S10Az, leading to increased processing yields, while a decreasing trend was noted in S10AA. VI had a significant effect on NaCl content in S10AA, resulting in a 45 % processing time reduction. The Peleg model accurately fitted the solutes content dynamics, suggesting that VI shortens the time it takes to reach equilibrium for NaCl and sucrose. Product texture characteristics were affected by the solution composition, with increased hardness in S10AA, but not by VI treatment. These findings enhance the understanding of fish pre-treatment operational variables and suggest the VI potential for streamlining processes in the fish industry.