Biogenic Amines as Hygienic Quality Indicators of Tuna. Relationships with Microbial Counts, ATP-Related Compounds, Volatile Amines, and Organoleptic Changes

Abstract

Changes in 10 biogenic amines throughout tuna storage at 0, 8, and 20 °C were studied. ATP-related compounds, volatile amines, microbial counts, and organoleptic assessment were also monitored. No statistical differences were found for those parameters between samples from different anatomical areas. Similar evolution profiles were observed for biogenic amines at the three temperatures, although the highest amounts were achieved, in general, in samples stored at 20 °C. Histamine was the prevailing biogenic amine throughout storage, and the defect action level of 50 μg/g was surpassed in samples stored at 8 or 20 °C before organoleptic rejection. A great increase in cadaverine and tyramine and a slight increase in putrescine were also observed. Formation of histamine, tyramine, and cadaverine seems to be related to mesophilic flora, Enterobacteriaceae and coliforms. Hygienic quality estimation by means of trimethylamine values and IMP ratio yielded inconsistent results in samples corresponding to the limit of organoleptic acceptance. In accordance with the results of this work, we proposed for tuna assessment the use of an index calculated from the sum of the contents of histamine, tyramine, cadaverine, and putrescine which showed good correlations with both time of storage and organoleptic assessment. Keywords: Biogenic amines; histamine; tuna spoilage; ATP-related compounds; volatile amines