What the hell is the Diacetyl?
The diacetyl, also known as butanodione or its funny version, butane-2,3-dione, is a chemical substance that appears naturally thanks to fermentation. This naughty little one appears in the kitchen as an artificial flavoring, but it is also strained in butter and various margarines, giving an irresistible touch to certain oils that we use in our daily recipes.
The Diacetyl in the Beer World
In the brewery, the diacetyl becomes a very commented guest, and not precisely because of how well he sings! Its aroma reminds us of the melted butter, those popcorn that drive us crazy in the cinema and the toffee that we always look for at parties. The first time it was paid attention to it was in the 19th century thanks to Louis Pasteur, who, arming himself with microscopes and immense curiosity, discovered that some bacteria were causing undesirable flavors in beer.
A Walk through History
It was not until 1939 that J. L. Shimwell made a transcendental connection between the diacetyl and its mantecous flavor, while between the 1950s and 1960s it was determined that brewing yeasts are responsible for producing this component. Interestingly, many drinkers cannot detect the diacetyl until it reaches 0.15 ppm, a mystery that is still being studied.
How is the Diacetyl Born? The Three Groups of Models
The production of diacetyl is not a random phenomenon, but originates from three key factors: yeast fermentation, bacterial contamination and the revered aging process. Do not underestimate the capacity of these microorganisms, as they have been studied for years.
1. The Role of Lewdness
It all starts with pyruvic acid and acetaldehyde, which are transformed into alpha-acetylactic acid right in the heart of yeast. As this acid escapes and oxidizes, it becomes diacetyl, which can be a dilemma, especially if yeast strains with low flocculation are chosen; it is as if they wanted to party too long!
2. The Shadow of Bacteria
Later, bacteria, such as Lactobacillus and Pediococcus intruders, arrive to turn the party upside down. They produce lactic acid, and when your beer starts to smell butter with an acidic touch, it is a sign that the evil was present. However, thanks to the new hygiene technologies, microcerveserías are better equipped to avoid these slips.
3. The ‘Fabulous’ Ageing
The aging can be a deposit of surprises: if yeast strains are not properly managed, they can leave a high level of alpha-acetylactic acid, which after being oxidized generates diacetyl. So, be careful to let time go unsupervised!
Tips for Keeping Diacetyl to Raya
Establishing proper brewing practices is the key to limiting the presence of diacetyl. Here are some tips that any good brewer should take into account:
- [‘Use quality yeasts that are alive and healthy.’, ‘Make sure you maintain a good aeration after cooling.’, ‘Develop a complete fermentation before taking any step.’, ‘Control the temperature during fermentation.’, “Performs a ‘diacetyl rest’ for lagers beers.”, ‘Choose quality malts that have a high nitrogen content.’, ‘Quickly cool the must.’, ‘Maintain rigorous sanitization practices.’, ‘Minimizes oxygenation during bottling.’, ‘Monitors the pH of cold must.’]
Looking to the Future: A Brewery World Without Diacetyl
The meticulous regulation and the continuous research in oenology and microbiology are the answer to advance towards beers of exceptional quality. With each smoothie, each bubbling and every drop, the brewers seek to perfect their art. On this journey, the diacetyl is only one of the many characters that star in the unexpected work of the brewery. Cheers for that!
