An analytical distinction between untreated and steam-treated roasted coffee

Up to now, no possibility exists to distinguish analytically between untreated and steam-treated coffees after the roasting process. In this paper, a method is proposed for this using the contents of carbohydrates in the gel chromatographic fraction of the coffee melanoidins with the highest molecular weight. This method was developed by the analysis of eight regular coffees, bought in different shops in Hamburg. Three equations are proposed, each with the carbohydrates galactose, rhamnose, glucose and mannose, that allow the aforementioned distinction equally well. Which of these three equations is the most suitable has to be proven by analysis of more coffees.