Influence of storage on hop-accentuated, top-fermented beers (Part 1)

Aroma stability | Based on the enormous success of US craft breweries, top-fermented, hoppy beers such as Pale Ales and India Pale Ales enjoyed significant production and sales growth, also in Germany. These beers are characterised by their specific sensory attributes created by dry hopping. As of about 2010, scientific studies initially focussed on reproducibility of dry hopping and achieving a consistent beer aroma with this process. As of about 2015, issues relating to stability of aroma and taste of these beers came to the fore.

S. pastorianus: From local obscurity to world domination

Microbial imperialism | The hybrid yeast S. pastorianus likely evolved spontaneously in the late Renaissance in the beer vats of Bavaria. Since then, it has replaced the once omnipresent S. cerevisiae in breweries throughout the world. This article traces this surprising development from its origins to the present and presents some tantalizing insights unearthed by the most recent genetic research.

Multifunctional dealcoholisation

The numbers speak for themselves | On the last International Beer Day on 2 August 2024, the German Federal Statistical Office published figures on the consumption on non-alcoholic beer in Germany. Over the last ten years, the amount of alcohol-free beer destined for sale has more than doubled (104 %). The increase in mixed beer beverages is much lower at 11 percent, with the production of beer with alcohol falling by about 14 percent in the same period [1].

Kombucha production: opportunities and challenges

Ensuring consistent quality | Kombucha’s popularity is booming due to its potential health benefits. While the production process is straightforward, consistently achieving the same flavor and quality remains a challenge. How can producers ensure consistent quality on an industrial scale?

Mixed fermentation of two yeasts for non-alcoholic wheat beer

Mixed fermentation | In recent years, innovations and process optimisations have been observed on a continuous basis in the ever-expanding market for low-alcohol and alcohol-free (< 0.5 %v/v alcohol) beers. In particular various technological processes or combinations thereof (thermal, membrane or biological processes) led to a strong diversification of the market.

Artificial intelligence in the fermenting room: predicting process data

AI in the brewing industry | The art of making beer is millennia old and in Germany looks back on a long tradition based on the Purity Law of 1516. While the fundamentals of brewing haven’t changed for centuries, industrial progress has caused the brewing sector to steadily evolve. Current developments in the most recent technological achievements, such as artificial intelligence (AI), illustrate the transition from the fourth industrial revolution (Industry 4.0) to the fifth (Industry 5.0) [1].

Age-specific fractionation of Saccharomyces using millifluidic systems

Advances in biotechnology | Yeast cells, Saccharomyces yeasts among others, are essential in biotechnological research. However, research is nowadays also directed to the question how the age of a cell has an influence on its function. Using up-to-date techniques, yeast cells can be sorted according to age. This innovative method reveals fascinating insights into age-related changes in yeast metabolism and gene activity of yeasts.

The consequences of a “Little Ice Age” and a summer brewing prohibition

The offspring wins | This is the third of a four-part article series about the historical evolution of our understanding of the nature and function of yeast in fermentation. It investigates the improbable conditions that made the unlikely hybridization of S. cerevisiae and S. eubayanus in late-Renaissance in Bavaria, as well as its subsequent survival, possible.

Fermentation, conditioning, storage: Problems and solutions

Troubleshooting | Fermentation upsets are reported increasingly frequently, e.g. primary fermentation becomes stuck, secondary fermentation does not proceed properly, yeast flocculates or remains in suspension. When trying to pinpoint the causes, the following statement is very frequently heard: “We did not change anything at all, but extract degradation is incomplete, we have diacetyl in the product” etc. So what’s causing these upsets?

Measuring the breath of beer

Yeast propagation | The thousand-year-old art of brewing is undergoing a significant transformation in our modern day and age thanks to scientific advance and technological development. The term ‘breath of beer’ refers to the volatile or fugitive gaseous components (VOCs) that are produced during beer fermentation. These volatile components, especially ethanol, can be measured to better understand and monitor the complex process of brewing.

A mysterious eucaryotic rendezvous in Bavaria

When Eubayanus met cerevisiae | This is the second part of a series about our understanding throughout history of the nature and function of yeast in fermentation. The first part (BRAUWELT International 5, 2024) dealt with the puzzling discovery of two side-by-side fermentations, “cold” and “warm”, in the small town of Nabburg, in Bavaria’s Upper Palatinate region, in 1483. It also dealt with the 2011 discovery of the wild S. eubayanus yeast in the high Andes in Argentina. A subsequent genome sequencing proved that this wild yeast was the missing second parent of S. cerevisiae. The current installment examines a few theories, some speculative, about how this South American yeast or its spores might have reached Bavaria – a question that is still not resolved, and subject of vigorous investigations.