How to Identify Roast Defects in Coffee Beans Based on the Volatile Compound Profile
Robert Rusinek1, Bohdan Dobrzański2, Anna Oniszczuk3
1Institute of Agrophysics Polish Academy of Sciences, Doświadczalna 4, 20-290 Lublin, Poland.
Molecules (Basel, Switzerland)
|December 11, 2022
Summary
This study identified volatile compounds in defectively roasted coffee beans, finding correlations between roast defects and specific compounds. An electronic nose effectively detected these roasting flaws in Arabica coffee.
Area of Science:
- Food Science
- Analytical Chemistry
- Sensory Science
Background:
- Coffee quality is significantly influenced by roasting processes.
- Roast defects can negatively impact the volatile compound profile and sensory attributes of coffee.
- Understanding these relationships is crucial for quality control in coffee production.
Purpose of the Study:
- To detect and identify volatile compounds in coffee from standard and defect roasting processes.
- To determine correlations between specific roast defects (underdevelopment, overdevelopment) and volatile profiles.
- To evaluate the efficacy of an electronic nose in identifying coffee roast defects.
Main Methods:
- Utilized gas chromatography/mass spectrometry (GC-MS) for volatile compound identification.
- Employed an electronic nose for defect detection and characterization.
- Roasted Arabica coffee beans ('Typica' variety) under controlled conditions to produce defectless, underdeveloped, and overdeveloped samples.
Main Results:
- Identified distinct volatile compound profiles associated with standard, underdeveloped, and overdeveloped roasted coffee.
- Established correlations between volatile compound groups and key roasting parameters (time to first crack, drying time, bean/air temperatures).
- The electronic nose successfully differentiated between defectless and defectively roasted coffee samples.
Conclusions:
- Roast defects significantly alter the volatile chemical composition of coffee.
- Specific volatile compounds are linked to identifiable roasting parameters and defects.
- Electronic nose technology offers a viable method for detecting coffee roast defects.
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