The
objective of this study was to analyze the effect of chloride, citric and
ascorbic acid dip treatments in conjunction with two types of packaging films
(with high and low gas permeability) on microbial growth in samples of pejerrey
fillets (Odonthestes bonaerensis) at
three storage temperatures (4°C, 0°C and -1.5°C). Colour, pH, texture
modification and chemical changes were also studied. Psychrotrophic
microorganisms, sp. were modelled by the Gompertz’ equation. Lag phase
duration, specific growth rate and maximum population density were calculated.
The activation energy (Eµ)
was calculated reaching values of 147 and 177 kJ/mol when the low permeability
packaging films were employed. We used psychrotrophic microorganisms, sp., as a
predictor of the shelf life of product. The application of treatment with
chloride, citric and ascorbic acids, extended 1 - 2 days the storage life of
the product (time to reach 106 CFU/g) when the packaging material
used was polyethylene. The use of chloride, citric and ascorbic acids and
vacuum packaging produced shelf life values of 7.7, >25 and >25 days at 4°C,
0°C and -1.5°C respectively. The products had very good organoleptic
characteristics, maintained their colour and texture appropriate, and absence
of pathogenic microorganisms. These values indicated that the growth models
were acceptable for expressing the growth of microorganisms on pejerrey
fillets, which can be applied to ensure the safety of fish and to establish
standards for avoiding microbial contamination.