Coffee is a popular drink and its consumption is constantly increasing. A large amount of coffee consumed significantly contributes to the total content of acrylamide, caffeine and other methylxanthines and trigonelline in the diet. The aim of this master's thesis was to determine the content of acrylamide, caffeine, theobromine, theophylline, xanthine and trigonelline in different coffee samples. We explored the effect of roasting parameters (temperature (220 and 240 °C) and time (17, 19 and 21 min)) and different methods of coffee preparation (moka, espresso and cold brew) on the content of the analyzed compounds. We analyzed 3 samples of green coffee, 18 samples of roasted ground coffee and 54 samples of prepared coffee drink. A higher content of acrylamide, caffeine and xanthine was determined in the roasted coffee of the C. canephora species, while a higher content of theobromine and theophylline was determined in the coffee of the C. arabica species. The highest acrylamide content was determined in samples roasted at a temperature of 220 °C and a time of 17 minutes. In all roasted coffee samples, the acrylamide content was below the reference value (400 ppb) set by Commission Regulation (EU) 2017/2158. In prepared coffee drinks (moka, espresso and cold brew), the highest contents of acrylamide, caffeine and xanthine were determined in the species C. canephora, while the highest contents of theobromine and trigonelline were determined in the species C. arabica. The content of acrylamide was higher in moka and cold brew coffee than in espresso coffee. We determined a higher caffeine content in moka and espresso coffee compared to cold brew coffee. We determined the highest contents of theobromine, xanthine and trigonelline in espresso coffee. In the case of theophylline, however, the differences between individual methods of coffee preparation were very small. We also analyzed 16 coffee samples from the market and some of them exceeded the reference value for acrylamide.
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