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Immobilised cells are increasingly being used in bio-industries and may also have benefits for the brewing industry. The major challenge to applying this technology successfully in breweries is focused on the main fermentation in combination with the secondary fermentation. In particular, the control and fine-tuning of the flavour profile during the main fermentation require further investigation. In this review, the influence of immobilised cell technology on the production of the flavour-active compounds (i.e. higher alcohols, esters and vicinal diketones) is discussed. Control strategies that are based on the manipulation of parameters during fermentation such as temperature, feed volume, wort gravity, wort composition and aeration are explained. Finally, bioreactor configurations that may facilitate immobilised cells in performing the primary fermentation are evaluated.

Immobilized cell technology has shown a significant promotional effect on the fermentation of alcoholic beverages such as beer, wine and cider. However, genetic, morphological and physiological alterations occurring in immobilized yeast cells impact on aroma formation during fermentation processes. The focus of this review is exploitation of existing knowledge on the biochemistry and the biological role of flavour production in yeast for the biotechnological production of aroma compounds of industrial importance, by means of immobilized yeast. Various types of carrier materials and immobilization methods proposed for application in beer, wine, fruit wine, cider and mead production are presented. Engineering aspects with special emphasis on immobilized cell bioreactor design, operation and scale-up potential are also discussed. Ultimately, examples of products with improved quality properties within the alcoholic beverages are addressed, together with identification and description of the future perspectives and scope for cell immobilization in fermentation processes.