KINETIC STUDY OF QUALITY DEGRADATION OF ATLANTIC SALMON (SALMO SALAR) MUSCLE DURING THERMAL PROCESSING AND IN RESPONSE TO ELECTROLYZED WATER AND MILD-THERMAL PROCESSING COMBINATIONS

• Main Author: Ovissipour, Mahmoudreza
• Other Authors: Sablani, Shyam, Rasco, Barbara, Tang, Juming
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: 2017
• Subjects: Protein Structure; Electrolyzed water; FTIR; Kinetics; Listeria monocytogenes; Thermal processing; Agriculture engineering; Food science; Atlantic salmon; Salmo salar
• Online Access: https://rex.libraries.wsu.edu/esploro/outputs/doctoral/KINETIC-STUDY-OF-QUALITY-DEGRADATION-OF/99900581516401842; https://rex.libraries.wsu.edu/view/delivery/01ALLIANCE_WSU/12350016620001842/13350016610001842

Thermal processing is used in food industry to control the Listeria monocytogenes but unfortunately, causes food quality degradation. To find the optimum processing conditions, a kinetic study is required to study quality changes in foods. Combining thermal processing with non-thermal processing can also decrease the effect of thermal processing on food quality. Overall objective of this study was to optimize the thermal processing of Atlantic salmon (Salmo salar) through a kinetics study, and to investigate the effect of different electrolyzed water (EO) solutions, including acidic electrolyzed water (AEW) and neutral electrolyzed water (NEW), alone and in combination, with mild thermal processing (50, 55, 60, 65 °C) at different exposure times on the inactivation of L. monocytogenes in Atlantic salmon fillets. Findings indicate that cook loss, area shrinkage, and protein denaturation parameters were best fitted to a first-order reaction and color parameters followed zero-order kinetics. Fourier transform infrared spectroscopy (FTIR) showed that increasing heating time and temperature reduced the α-helix peak (protein denaturation) and increased the β-sheet peak intensity (protein aggregation). The protein denaturation activation energy from Differential Scanning Calorimetry (DSC) was 301 kJ/mol. The results of the study show that NEW has stronger antimicrobial properties compared to AEW which caused 5.6 log10 CFU/g reduction in samples treated 65 °C for 10 min. The salmon muscle secondary protein structure showed that NEW had less impact on the protein compared to AEW, as shown by a PCA model based upon FTIR spectral changes in the protein spectral region. In addition, the FTIR spectra for L. monocytogenes showed that the NEW and AEW had different impacts on the bacterial cell wall; this might be due to the form of available chlorine in NEW and AEW and to the difference in pH. In conclusion, FTIR, and dielectric properties were able to show the protein denaturation and aggregation which were consistent ...