|Walker, Hannah - Eastern Mennonite University|
|Lehman, Katherine - Eastern Mennonite University|
|Siderhurst, Matthew - Eastern Mennonite University|
Submitted to: Journal of the Science of Food and Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/26/2018
Publication Date: 11/7/2018
Citation: Walker, H.E., Lehman, K.A., Wall, M.M., Siderhurst, M.S. 2019. Analysis of volatile profiles of green Hawai'ian coffee beans damaged by the coffee berry borer (Hypothenemus hampei). Journal of the Science of Food and Agriculture. 99:1954-1960.
Interpretive Summary: Coffee berry borer (CBB) damage is known to cause a distinct off-flavor in coffee brewed from infested beans. Some properties of coffee flavor are attributed to small volatile compounds, therefore, the volatile profiles of coffee beans can provide valuable insight into their flavor and quality. In this study, an automated head space, gas chromatography, mass spectroscopy analytical method was developed for the study of volatiles in green coffee beans exhibiting various levels of visible damage by coffee berry borer. The relative concentrations of eight prominent volatiles were determine as potential markers for CBB damage. Volatile profiles of green coffee beans were differentiated from undamaged samples at three levels of damage.
Technical Abstract: Damage caused by the coffee berry borer (CBB), Hypothenemus hampei, leads to off-flavors in coffee. Automated headspace sampling (AHS) and gas chromatography/mass spectrometry (GC/MS) were used to investigate changes in the volatile profiles of CBB damaged green coffee beans. Green coffee from three coffee farms on the Island of Hawaii were sorted into three levels of CBB damage: non-damaged, slightly damaged (1-2 pinholes/bean), and heavily damaged (>2 pinholes/bean). Distinct differences were found between coffee samples based on the amounts of eight prominent volatiles. Increasing CBB damage was particularly correlated with increases in both hexanal and 2-pentylfuran. Principle component analysis showed clustering of non-damaged green beans, which did not overlap with the slightly or heavily damaged clusters. Good separation was also found between a mixture of 50% slightly and non-damaged coffee. However, 20% slightly damaged and non-damaged coffee clusters showed strong overlap.