Effect of modified atmosphere storage, cetylpyridinium chloride, and X-ray irradiation on pathogens and quality of catfish fillets.

摘要

The effect of carbon dioxide (CO2) and gaseous ozone (O 3) atmosphere, cetylpyridinium chloride (CPC), and X-ray irradiation on Listeria monocytogenes (Lm), Salmonella Typhimurium (ST), psychrotrophic bacteria (PPC), lactic acid bacteria (LAB), anaerobic bacteria (AA), water holding capacity (WHC), surface color, instrumental texture, oxidative rancidity (TBARs), cooking loss, pH, and sensory evaluation (appearance, texture, odor, and overall acceptability) of raw and baked catfish fillets were studied.; Both Lm and PPC were reduced by CO2, but not ST, LAB, and AA of catfish fillets. Ozone lowered PPC, but did not affect Lm, ST, LAB, and AA. All treatments did not affect most physicochemical characteristics of raw and baked fillets. However, WHC and hue angle of raw fillets varied with treatment, with no clear trend. Ozone increased TBARs of catfish fillets, but the value was lower than the objectionable levels for fish. Sensory ratings of raw and baked catfish fillets were not affected by CO2 or O 3, except odor scores for O3 fillets were lower. Shelf-life of catfish fillets was extended by 150% and 50% by CO2 or O 3, respectively.; At ≤1%, CPC slightly reduced Lm, ST, PPC, LAB, and AA of catfish fillets. Surface color of raw fillets was changed by CPC. Adverse effects on appearance and overall acceptability of raw fillets were also produced by CPC. Surface color of baked fillets was changed by CPC, but not sensory ratings.; Irradiation at 2 or 3 kGy reduced 4.8 log CFU/g Lm and 4.7 log CFU/g ST inoculated on catfish fillets. Using 2 to 3 kGy irradiation reduced PPC, LAB, and AA of catfish fillets by 40 to 60%. Irradiation produced minor effects on physicochemical characteristics of raw and baked fillets, but produced adverse effects on sensory ratings. Irradiation caused excessive superficial exudate and produced irradiation-induced off-odors. Irradiation at 2 or 3 kGy extended shelf-life of iced catfish fillets by more than 24 d with the added safety of possibly eliminating pathogens.