Green beer

Great Salt Lake Greek fire Green acids Green beer... 

Fig. 12. Fermenting and storing (1 = fermenting tank 2 = centrifuge (green beer separator) 3 = green beer cooler and, 4 = storage tank).

The system developed by Cultor (Finland) is industrially available and has been operational at industrial scale (1 million hi per year) since 1993. This accelerated maturation system is based on heat treatment of green beer (10 min at 90 °C for complete conversion of a-acetolactate to diacetyl) followed by reduction of diacetyl to acetoin during maturation with a continuous immobilized yeast system operating at a retention time of 2h (Pajunen, 1996). This packed-bed immobilized yeast bioreactor system has found industrial application also in continuous alcohol-free beer production (Mensour et al., 1997). 

Green beer Freshly fermented beer that has not been conditioned or matured. 

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