Biochemical, microbiological and sensory assessment of freshness in ice stored flounder (Paralichthys patagonicus).

MASSA, A. E.; PALACIOS, D.; PAREDI, M. E.; CRUPKIN, M.

Río de Janeiro. Brasil.

Congreso; 2nd Mercosur Congress on Chemical Engineering - 4th Mercosur Congress on Process Systems Engineering (ENPROMER); 2005

Quality characteristics of flounder (Paralichtys patagonicus) kept in ice were evaluated by monitoring changes in biochemical, microbiological, and sensory parameters over a 12-day storage period. During this study ATP and ADP were not detected. The initial content of AMP was 2.36 ± 0.45 µmoles/g, afterwards this value lowered rapidly to zero. The initial IMP concentration was 10.50 ± 0.20 µmoles/g. This value decreased 55% during the first two days of storage and then descended gradually. The HxR content was barely detectable (< 0.1 µmol/g) at all sampling times. The levels of Hx and the K-value significantly (p<0.01) increased until the seventh day and then remained approximately constant. The pH of muscle fluctuated between 6.6 and 7.0. Ice stored flounder was considered microbiologically acceptable for 7 days with aerobic plate counts reaching < 107 CFU/g. The sensory evaluation was made by the Quality Index Method (QIM) that linearly increased (r2=0.96) with keeping time on ice. The members of the panel considered fish unacceptable after 7 days. All the parameters analyzed indicate that the shelf life of iced flounder was of 7 days.