Coffee aroma – the best part of the coffee extract – is volatile. In order to avoid loss of the aroma when the coffee extract is evaporated before spray drying or freeze drying, the aroma fraction must be recovered and added to the coffee concentrate.
The aroma fraction from the FIC™ extraction plant is passed through an aroma recovery plant where the aroma is stripped off by heating the coffee extract to a temperature of higher than ° ̊C. As it passes a flash chamber operated under vacuum, the aroma rich vapour is separated, distilled, and concentrated in a distillation column and then condensed and cooled. Further concentration of the aroma can be done in a membrane filtration (reverse osmosis) plant. The liquid aroma is collected and stored in a tank. From here, the aroma is added to the concentrated extract before further processing – either sold as final coffee extract – or spray dried or freeze dried. All flowsheet animations are available in the GEA Niro download area.