Using microwave distillation-solid-phase microextraction--gas chromatography--mass spectrometry for analyzing fish...

Area of Science:

• Analytical Chemistry
• Food Science
• Environmental Science

Background:

• Volatile compounds in fish tissue significantly impact sensory quality and can indicate contamination.
• Accurate identification and quantification of off-flavor compounds are crucial for food safety and quality control.

Purpose of the Study:

• To develop and validate a novel analytical technique for the comprehensive analysis of volatile compounds in fish tissue.
• To establish a quantitative method for determining specific off-flavor contaminants, namely 2-methylisoborneol and geosmin.
• To compare the performance of the developed instrumental method with sensory evaluation by human flavor checkers.

Main Methods:

• Microwave distillation-solid-phase microextraction-gas chromatography-mass spectrometry (MD-SPME-GC-MS) was employed for volatile compound extraction and analysis.
• A qualitative analysis identified 174 volatile compounds present in the fish tissue headspace.
• Quantitative analysis for 2-methylisoborneol and geosmin utilized borneol as a surrogate standard and decahydro-1-naphthol as an internal standard.

Main Results:

• The developed method successfully identified 174 volatile compounds in fish tissue.
• A linear calibration curve was achieved for 2-methylisoborneol and geosmin in the range of 0.1 to 5 ppb.
• The method demonstrated a recovery rate of 60% for these off-flavor contaminants at a concentration of 2.5 ppb.

Conclusions:

• The MD-SPME-GC-MS technique provides a robust and sensitive approach for analyzing volatile compounds in fish.
• The quantitative method is effective for determining key off-flavor contaminants, ensuring fish product quality.
• The instrumental method showed good agreement with human sensory evaluation, validating its practical applicability.