Furanic compounds and furfural in different coffee products by headspace liquid-phase micro-extraction followed by gas chromatography–mass spectrometry: survey and effect of brewing procedures

Abstract

In this study, the levels of furan, 2-methylfuran, 2,5-dimethylfuran, vinyl furan, 2-methoxymethyl-furan and furfural in different coffee products were evaluated. Simultaneous determination of these six furanic compounds was performed by a head space liquid-phase micro-extraction (HS-LPME) method. A total of 67 coffee powder samples were analysed. The effects of boiling and espresso-making procedures on the levels of furanic compounds were investigated. The results showed that different types of coffee samples contained different concentrations of furanic compounds, due to the various processing conditions such as temperature, degree of roasting and fineness of grind. Among the different coffee samples, the highest level of furan (6320 µg kg⁻¹) was detected in ground coffee, while coffee-mix samples showed the lowest furan concentration (10 µg kg⁻¹). Levels in brewed coffees indicated that, except for furfural, brewing by an espresso machine caused significant loss of furanic compounds.

Furan and Methylfurans in Foods: An Update on Occurrence, Mitigation, and Risk Assessment

“…The studies published to date have shown no significant differences in furan and alkylfuran levels in caffeinated versus noncaffeinated beverages (Becalski et al., ). Instant coffees manufactured by spray drying seem to contain relatively lower amounts of furan versus more mildly freeze dried instant coffees (Chaichi et al., ). Furthermore, the manufacturing process, particularly the degree of aroma retention, will most likely be a decisive factor in final furan/methylfuran content, as the volatile coffee aroma fraction will contain a significant proportion of the furan present.…”

“…Other determinants of furan in the cup are the brewing method as well as final preparation of the beverage prior to consumption. Furan and 2‐MeF dissipate rapidly upon brewing, with more than 60% 2‐MeF “lost” when brewed with an espresso machine or by boiling (Chaichi et al., ). The same authors reported losses of around 45% when preparing commercial instant coffee (reconstituted at 80 °C with prepared product maintained at 43 °C).…”

“…In fact, substances with a furan moiety are a major chemical class in roast and ground coffees, including compounds such as, for example, 2-furfuryl alcohol, furfural, 2-methoxymethylfuran, furfuryl acetate, 2-furfuryl, 2-MeF, 2,5-diMeF, and vinylfuran (Chaichi, Ghasemzadeh-Mohammadi, Hashemi, & Mohammadi, 2015;Petisca, Pérez-Palaciosa, Farah, Pinhoa, & Ferreira, 2013;Shen et al, 2016). Several reports on the occurrence of furan and methylfurans in commercial coffees are available in the literature (Altaki, Santos, & Galceran, 2011;Arisseto et al, 2011;Becalski, Halldorson, Hayward, & Roscoe, 2016;Becalski et al, 2010;Bicchi et al, 2011;Chaichi et al, 2015;Guenther, Hoenicke, Biesterveld, Gerhard-Rieben, & Lantz, 2010). Published data show that furan is present in roast and ground coffees in the range of 0.7 to 3.45 mg/kg (on the basis of powder not on the beverage as consumed).…”

Increasing the Sustainability of the Coffee Agro-Industry: Spent Coffee Grounds as a Source of New Beverages

“…Among the aldehydes, furfural was identified at a high level in the distillates D1 and D2. This compound is formed during processes that involve heating or roasting, e.g., roasting of coffee beans and/or distillation, due to degradation of fermentable pentose sugars, caused by heating in acid conditions, and/or Maillard reaction [34][35][36]. Thus, high amounts of furfural might be attributed to the presence of high quantities of residual pentose sugars due to unfavourable fermentation conditions of the substrate.…”

Characterization of Turkish-Style Boiled Coffee Aroma by Gas Chromatography and Mass Spectrometry and Descriptive Analysis Techniques

“…Various studies regarding the effect of Turkish coffee traditions and coffee houses on social life as well as studies on traditional equipment used for preparing and serving Turkish coffee and also studies regarding the health effects of Turkish coffee, its antioxidant capacity and determination of furanic compounds and furfural in Turkish coffee have been conducted [1][2][3][4][5][6][7][8][9][10][11]. For this purpose, the headspace volatiles of Turkish-style Boiled Coffee, brewed from light, medium and dark roasted, ground Arabica coffee beans, isolated by solid phase micro extraction (SPME) were analysed by gas chromatography-mass spectrometry (GC/MS) analysis and descriptive sensory analysis was performed..…”