Heavy-Metal Contents and the Impact of Roasting on Polyphenols, Caffeine, and Acrylamide in Specialty Coffee Beans

Abstract

The aim of this study was to determine the effect of roasting on the contents of polyphenols (PPH), acrylamide (AA), and caffeine (CAF) and to analyze heavy metals in specialty coffee beans from Colombia (COL) and Nicaragua (NIC). Samples of NIC were naturally processed and COL was fermented anaerobically. Green beans from COL (COL-GR) and NIC (NIC-GR) were roasted at two levels, light roasting (COL-LIGHT and NIC-LIGHT) and darker roasting (COL-DARK and NIC-DARK), at final temperatures of 210 °C (10 min) and 215 °C (12 min), respectively. Quantitative analyses of PPH identified caffeoylquinic acids (CQA), feruloylquinic acids, and dicaffeoylquinic acids. Isomer 5-CQA was present at the highest levels and reached 60.8 and 57.7% in COL-GR and NIC-GR, 23.4 and 29.3% in COL-LIGHT and NIC-LIGHT, and 18 and 24.2% in COL-DARK and NIC-DARK, respectively, of the total PPH. The total PPH contents were highest in COL-GR (59.76 mg/g dry matter, DM). Roasting affected the contents of PPH, CAF, and AA (p < 0.001, p < 0.011 and p < 0.001, respectively). Nickel and cadmium contents were significantly higher in the COL-GR than in the NIC-GR beans. Darker roasting decreased AA content, but light roasting maintained similar amounts of CAF and total PPH.

Acrylamide: impact of precursors concentration, origin, post‐harvesting process and roasting level in high‐quality arabica and Robusta coffee

“…AA levels were lower than those presented by the EFSA Scientific opinion on AA in food of 2015 (the mean level, independent from the roasting degree, is 185 μg kg −1 vs 249 μg kg −1 ). Additionally, more recent scientific works (Bertuzzi et al ., 2017; Schouten, Tappi, Angeloni, et al ., 2020; Várady et al ., 2021) provided with AA higher than ours, except for the study by (Lachenmeier et al ., 2018) which reported comparable data. However, the number of samples involved in this study was less representative (only 2 samples).…”

Evaluation of heavy metals in Roasted Coffee powder in Iran and Turkey

“…The quantity of heavy metals (Copper, Lead, Chrome, Cadmium, Nickel, Aluminum, and Mercury) in roasted coffee beans from Colombia and Nicaragua was evaluated by ICP-MS (Várady et al, 2021). Nickel and cadmium in Colombian samples were higher than other samples but in the standard range.…”

Ethnopharmacological study of the genus Coffea and compounds of biological importance

“…On the other hand, the contents of polyphenols and phenolic acids are higher in organic crops (Table 3) because they act as a natural protection for plants (Górecki & Hallmann, 2020;Król et al, 2020). The content of chemical compounds in coffee beans also depends on the processing and storage of the beans, the time and level of roasting of the beans, and the type of preparation and extraction used to create beverages (Hutachok et al, 2020;Jeszka-Skowron et al, 2016;Várady et al, 2021). During the roasting of coffee beans, some of the chemical components in the beans are degraded; for example, the decrease in the content of phenolic compounds is correlated with the roasting temperature and time, and it has been reported that the CGA content is lower than 6%.…”

“…Another species studied due to its importance and high demand in the market and widespread consumption is C. canephora; both green and roasted beans of this species as well as soluble coffee have been studied, highlighting the presence of CGAs and caffeine (Table 5). Sangta et al, 2021 and aspartic acid and the carbonyl groups of reducing sugars such as glucose and fructose, giving rise to compounds such as melanoidins and acrylamides (Endeshaw & Belay, 2020;Várady et al, 2021). Melanoidins give the beans a brown pigment and flavor and color to the beverage.…”

“…The consumption of coffee beverages is based on their ethnopharmacological uses and biological properties attributed to their chemical components. In the Coffea species, the concentrations of chemical components vary among species and cultivation places; besides, some compounds are degraded during the roasting process, and some of them can be toxic pollutants (Farah & Donangelo, 2006;Ruiz-Palomino et al, 2019;Castaldo et al, 2020;Várady et al, 2021).…”