Coffee is a well-known beverage being processed from coffee beans of either Arabica and/or Robusta. Observational and experimental research on coffee shows positive health impact. Coffee often relates with dyspeptic condition (i.e. Gastric release) and manifest Gastro-esophageal Reflux (GERD) and peptic ulcer (PU) diseases. Despite much contradictive results, epidemiological studies were inclined towards debunking the possible relationship between coffee and gastrointestinal diseases. Putative compounds were experimentally found to be chlorogenic acid (CQA), caffeine (CAFF), βN-alkanoyl-5-hydroxytryptamide (C5HT), N-methylpyridinium (NMP), chlorogenic acid lactones (CQL) and hydroxybenzenes in coffee that leads to gastric release. The type 2 bitter taste receptors (TAS2Rs), were physiologically involve in the gastric acid secretion. These contrarily results need much considerations involving genetic, types of coffee used and the compounds in coffee that might interact causing gastrointestinal problem
Gastrointestinal health

Introduction: This study was carried out to quantify the selected bioactive compounds (i.e., chlorogenic acids, caffeine, and N-methylpyridinium) in instant coffee and to analyze its correlation with the gastric release effect of the HGT-1 cell line. Methods: Selected bioactive compounds in regular (REG), low sugar (LS), low fat (LF), white coffee (WC), white coffee low acid (WCA), decaffeinated (DC), and instant black coffee (BC) were quantified using HPLCDAD (high-performance liquid chromatography diode array detection) system and flow cytometry analysis for its gastric release effect when treated with HGT-1 cell. Results: The HPLC data showed the content of caffeine (60,212 ± 212 µg/ml) and chlorogenic acid (35,779 ± 3027 µg/ml) were significantly high in BC while the lowest caffeine value was found in DC coffee. Chlorogenic acid in other instant coffee samples showed insignificant content distinctions. As for N-methylpyridinium (NMP), the highest content was found in BC (565 µg/ml) and the lowest value was detected in WC (52 µg/ml) coffee. Gastric release activity by HGT-1 cells was significantly higher in DC and REG coffee treatment. Pearson correlation showed no significant correlation between the quantitative data and gastric release activity by HGT-1 cells. Conclusion: The selected bioactive compounds contained in instant coffees were unable to stimulate gastric release.