Quantitative Validation of the In-Bean Approach in Coffee Roasting

• Published in: Journal of agricultural and food chemistry 2020-04, Vol.68 (17), p.4732-4742
• Main Authors: Poisson, Luigi, Pittet, Jonathan, Schaerer, Anja, Mestdagh, Frédéric, Davidek, Tomas
• Format: Article
• Language: English
• Subjects: Coffea - chemistry; Cooking - methods; Flavoring Agents - chemistry; Gas Chromatography-Mass Spectrometry; Hot Temperature; Odorants - analysis; Seeds - chemistry; Volatile Organic Compounds - chemistry
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/acs.jafc.9b05436

The representativeness of the so-called biomimetic “in-bean” technique was studied by following the formation of target aroma compounds during the roasting course (10 points from 0 to 400 s) in recombined coffee beans and non-treated green coffee reference beans. For this purpose, the water-soluble fraction was replaced by a biomimetic recombinate in reconstituted beans prior to roasting. The targeted analysis of key aroma compounds was performed by means of the stable isotope dilution assay and solid-phase microextraction–gas chromatography–mass spectrometry of roasted and ground coffee samples. The results were compared to the quantitative data on a green coffee reference roasted under the same conditions. The results showed similar formation kinetics for most of the evaluated volatiles, such as Strecker aldehydes, alkylpyrazines, or α-diketones. In addition, the final quantities of key odorants in both types of samples were quite comparable. Hence, the refined biomimetic approach was validated as a valuable tool in studying different aspects of flavor formation upon coffee roasting.