Study on the Volatile Organic Compounds and Its Correlation with Water Dynamics of Bigeye Tuna (<i>Thunnus obesus</i>) during Cold Storage

Abstract

Volatile organic compounds (VOCs) and water play a key role in evaluating the quality of aquatic products. Quality deterioration of aquatic products can produce some off-odour volatiles and can induce water content changes. However, no previous study has investigated a correlation between water dynamics and VOCs of bigeye tuna during cold storage. The changes in VOCs, water dynamics and quality attributes of bigeye tuna (Thunnus obesus) upon storage at 0 °C and 4 °C for 6 days were investigated. The results showed that the values of ATP, adenosine diphosphate (ADP), adenosine monophosphate (AMP), T21 (trapped water) and the relative value of T1 decreased (p < 0.05), while drip loss and histamine contents increased (p < 0.05), which indicated quality deterioration during cold storage. With haematoxylin and eosin (HE) staining, muscle tissue microstructure was observed. VOCs such as hexanal, heptanal, 4-Heptenal, (Z)-, pentadecanal-, 1-pentanol, 1-hexanol significantly increased, which sharply increased the content of off-odour volatiles. T21 was positively correlated with 1-octen-3-ol, 1-penten-3-ol, while T21 was negatively correlated with hexanal, 1-hexanol. Therefore, good correlations between water dynamics and some VOCs were detected during quality deterioration of bigeye tuna throughout cold storage.

Keywords

• bigeye tuna (<i>Thunnus obesus</i>)
• water dynamics
• volatile organic compounds
• ATP-related compounds
• low-field nuclear magnetic resonance
• gas chromatography/mass spectrometry (SPME-GC/MS)