Diacetyl Production, Reduction and Control in Beers Brewed with Raspberries and Other Adjunct Sugar Sources
- Research Date
- 2021
- Authors
- Nichole Shriner, Donald Morelli
- Priorities
- New Varieties, Product Development
- Crop Categories
- Fruit
- Beverage Categories
- Beer
The usage of fruits in beers is one way that craft breweries in Michigan can create their individual identity while embracing Michigan made products. While fruits can be grown in many states, the climate, soil and growing methods vary based on location and thus each produce slightly different varieties of fruit. As Michigan breweries being to expand their beer brands and hopefully their use of local raw materials, it is important to be aware of the implication ingredients can have on the final product. In conversation with several breweries, it was made clear that the use of fruit or fruit puree can have an impact on total VDK production and degradation by yeast. Diacetyl and total VDK is an industry standard indicator of a beer’s quality and readiness. Moreover, the total Vicinal Diketones (VDKs) are a group of flavor components in beer, most notably 2,3-butanedione (generally referred to as diacetyl) and 2,3-pentanedione. The formation and degradation of total VDK is dependent on many factors including fermentation temperature, aeration level, nutrients including protein and amino acids, bacterial contamination, and yeast strain. It was seen through experimentation that total concentration of VDK and VDK degradation were both decreased when beers were brewed with raspberry puree. Additionally, the type of puree and the use pesticides on raspberries indicated variability in the presence of diacetyl in the raw materials themselves. It is suggested for every brewer who intends to use raspberries or other fruits, to discuss with their fruit grower or raspberry producer the methods of which the fruit is grown or puree is produced. Work should be directed into minimizing diacetyl production and brewers should be made aware of unexpected VDK concentration behavior.