At NKG Kala Hamburg (KALA), the largest and most modern green coffee centre for storage, production, goods handling and logistics in Europe, the steaming process for green coffee has been part of the service portfolio for 40 years. In 2006, Neuhaus Neotec built a new, modern green coffee silo with coffee steaming plant for NKG Kala Hamburg, in addition to many other coffee processing facilities. In the spring of this year, NKG commissioned a steaming plant delivered by Neuhaus Neotec for small batches to enable its customers to carry out trials on a trial scale before moving on to green coffee treatment with large throughputs.
To optimise different green coffee qualities before roasting, the process of vaporisation with water vapour is often used. This so-called "steaming" of the green coffee offers a wide range of applications: It is used for Arabicas to produce a milder cup by removing irritants and bitter substances. Contaminants can also be reduced. The coffee waxes on the surface of the green coffee can thus be reduced, which in turn has suggestively a positive effect on the digestibility of the coffee.
Steam treatment can also be used to optimise the taste of flat Arabica coffees. It is also possible to create an interesting acid profile in rather low-acid Robusta coffees by means of steaming.
Pure saturated steam is used for the process, the water for which comes from KALA's own well, which supplies water from a depth of 330 metres.
By varying the different parameters of steam pressure, amount of steam and time, it is possible to achieve a wide variety of results in green coffee treatment. To enable roasters to test the vaporisation of their green coffees on a small, manageable scale of 30 kg per batch on site in Hamburg, KALA 2022 acquired a steaming test plant from Neuhaus Neotec, which its sister company DEVEX had developed.
With this plant, the optimal processing parameters for roasting can be developed with customers for individual components or also mixtures. The plant is set up like the large industrial plants, only on an experimental scale. Through many tests and trials, Alexander Jank, head of the steaming plant at NKG Kala Hamburg, has done the elaborate preliminary work so that the parameters can be transferred from small to large and so that the products on the large plants are identical to those tested on the test plant.
Roasting customers of Neuhaus Neotec can also have trials with the steaming of their green coffees carried out at NKG Kala Hamburg, because the two companies work closely together in this area.
