Potential using of infrared thermal imaging to detect volatile compounds released from decayed grapes

Area of Science:

• Food science
• Analytical chemistry
• Spectroscopy

Background:

• Fruit spoilage involves changes in volatile compound composition.
• Infrared spectroscopy offers a potential method for analyzing these volatile compounds.
• Discriminating fruit decay states is crucial for quality control.

Purpose of the Study:

• To develop and validate an infrared spectroscopy method for discriminating grape decay states.
• To simplify feature spectra extraction and visualize volatile compound gas plumes.
• To propose semi-quantitative indicators for analyzing volatilization gradients.

Main Methods:

• Utilized infrared spectroscopy on volatile compounds from decayed grapes.
• Employed a custom-made wavelength filter with an infrared thermal camera.
• Developed feature spectra extraction and gas plume visualization techniques.
• Proposed accumulated gray value and imaging area as semi-quantitative indicators.

Main Results:

• Successfully discriminated fresh, slightly/moderately decayed, and seriously decayed grapes.
• Achieved high classification ratings: 100% for fresh, 93.3% for serious decay, and 90% for slight/moderate decay.
• Demonstrated the method's effectiveness in analyzing alcoholic volatiles.

Conclusions:

• Infrared thermal imaging is a viable, rapid technique for assessing grape decay.
• The proposed method allows for semi-quantitative analysis of volatile compounds.
• This approach has potential applications in food quality and safety monitoring.