FLUORESCENCE FORMATION BY INTERACTION OF ALBACORE (THUNNUS-ALALUNGA) MUSCLE WITH ACETALDEHYDE IN A MODEL SYSTEM

The role of acetaldehyde (AcH) in producing fluorescent compounds as a result of interaction with food constituents was studied. A model system consisting of albacore (Thunnus alalunga) muscle and AcH in 0.1 M phosphate buffer (pH 7.0) was used. Fish muscle was submitted to three different temperatures (5, 15, and 30-degrees-C) and four different concentrations of AcH (0, 1, 2, and 5%) during 1 month. Resulting fluorescent compounds were analyzed in the aqueous and organic extracts at three different excitation/emission maxima wavelengths: 327/415, 393/463, and 479/516 nm. Brown color formation was also measured in organic extracts at 420 nm. A strong relationship between fluorescence formation as a function of AcH concentration, time, and temperature of reaction was evident. An augmentation in all three variables produced a significant shift of fluorescence to higher excitation/emission maxima wavelengths which was accompanied by a marked increase in browning.