A Review of Flavour Formation in Continuous Beer Fermentations*

Abstract

The attractive prospect of a continuous beer fermentation system consists mostly of the accelerated transformation of wort into beer. Although continuous beer fermentation has been studied as a promising technology for several decades, the number of industrial applications is still limited. The major obstacle hindering the extensive industrial exploitation of this technology is the difficulty in achieving the correct balance of sensory compounds in the short time typical for continuous systems. This paper offers an integral view on the particularities of continuous systems, which may impart beer a sensorial character distinct from conventionally fermented counterparts. The main groups of flavour active compounds are discussed from the perspective of possible control strategies by means of process parameters and strain selection.

Application of Non-Saccharomyces Yeasts Isolated from Kombucha in the Production of Alcohol-Free Beer

“…Wort aldehydes form mainly during mashing and boiling, but are also partially formed during fermentation by the yeast. They can originate from oxo-acids via the anabolic process, and from exogenous amino acids via the catabolic pathway [53]. Ethanol plays a significant role in the reduction of the worty character of the beer.…”

Fermentation Efficiency of Cells Immobilized on Delignified Brewers' Spent Grains after Low- and High-Temperature Thin Layer Thermal Drying

“…Many researchers have focused on alternative uses of this agro-industrial by-product, including evaluation as raw material for food or feed production, energy production, and other biotechnological applications [10,11]. Specifically, the use of fresh (nontreated) or delignified BSG (DBSG) as solid supports for yeast immobilization led to the production of biocatalysts highly efficient for alcoholic fermentation processes, even at very low temperatures [8,9,12,13]. Therefore, to combine the need for both utilization of BSG and production of commercial biocatalysts efficient for alcoholic fermentation processes at extreme conditions, an investigation on a simple technique for low-temperature thermal drying of yeast immobilized on DBSG was conducted.…”

Influence of Mashing Profile Curve and Addition of Proteases on the Composition of the Wort and Beer

“…These amino acids are assimilated by yeast during the fermentation process, 8,28 being used to produce active compounds of the beer flavor. 29,30 The validated method was linear in the range of 50-1000μg ml -1 for Cys and Lys, 25-1000μg mL -1 for His and Arg, 10-200μg mL -1 for Trp and 2.5-100μg ml -1 for Phe, with correlation coefficients greater than 0.9998. In addition, the proposed method demonstrated good accuracy and recovery of amino acids in sweet worts (83.1-96.2%).…”