[Studies on coffee and coffee substitutes. XIX. Dependence of the quantity of a highly polymeric galactomannan on the degree of extraction coffee-extracts (author's transl)].

In extracts of Columbia Arabica Coffee the content of galactomannan precipitable with alcaline copper solution decreases slowly up to an extraction yield of 43.6%; it decreases somewhat more rapidly with higher extraction yields. An extract of Angola Robusta Coffee showed opposite behaviour. In this case the content of galactomannan increased with the extraction yield, although not evenly. Calculated on the basis of roasted coffee solids the extract of the Arabica coffee had a rather limited range precipitable polysaccharide, the Robusta coffee in contrast with rated increased amounts of galactomannan. The different behaviour of the two coffee varieties may be due to mote or less strong binding of this high-polymer carbohydrate to the cell wall.