QUALITY DIFFERENCES ASSESSMENT IN CANNED SARDINE (SARDINA-PILCHARDUS)BY FLUORESCENCE DETECTION

Chilled (0, 2, 6, 10, 13, and 15 days) and frozen (0, 0.5, 2, 4, 8, an d 12 months) sardines were used to determine the influence of such sto rage times of fish over the quality of the final canned product. Tradi tional determinations of lipid quality (free fatty acids content, thio barbituric acid index, and polyene index) were studied and compared wi th the formation of fluorescent compounds expressed as the ratio betwe en fluorescence readings taken at two excitation/emission maxima (393/ 463 and 327/415 nm). No clear correlations were found between the comm on measurements of lipid deterioration and the time of storage prior t o canning. Satisfactory correlations were found between the fluorescen ce ratio obtained from the filling medium of cans and the time of stor age of the starting material (r = 0.90 and 0.91 in brine-and oil-canne d samples, respectively). According to the present results, fluorescen ce detection of interaction compounds can provide a rapid and sensible method to assess quality differences in the final product as it relat es to the quality of the raw material used.