Jens Magnus Eiken, Global Product Manager Brewing, DuPont Industrial Biosciences
Long hot summers cause many people to dream of drinking a nice cold beer. Unfortunately, heat and drought reduce harvest yield leading to higher prices for malting barley. High temperatures and lack of rain also cause structural changes in the barley kernel such as higher protein levels, higher Free Amino Nitrogen (FAN) levels, lower limit dextrinase levels and the risk of reduced final wort and beer fermentability. Challenges for brewers can include finding measures to overcome higher gelatinization temperatures, lower speed of mash separation and higher costs. DuPont™ Laminex® and Diazyme® enzymes help brewers to overcome these obstacles to maintain high production output and quality while reducing costs and CO2 emissions.
The summer of 2018 was hot and dry with record high temperatures across Northern Europe, as well as significantly reduced rainfall and drought in many countries. Although a larger area of spring barley was planted in 2018, the heatwave and accompanying drought have led to reduced harvest yields of malting barley across the region with yields in some areas down by as much as 50%.
Initial analysis of the 2018 malting barley harvest indicates exceptional health. The kernels are fewer and larger. Levels of fungal infections such as fusarium are very low which means reduced risk of gushing. Due to the high temperatures, the harvest has high average levels of protein (>12%), with a consequent reduction in the level of starch.
The long hot summer has led to high protein levels, lower starch content, and higher starch gelatinization temperatures in the barley kernel (this year approximately 64°C vs 61°C in 2017). Subsequently there is overall reduced enzyme activity and a reduction in starch conversion and therefore yield.
Higher gelatinization temperatures can reduce the speed of mash separation and lead to lower wort fermentability. Brewers can overcome these filtration issues by using our Laminex® and Diazyme® ranges of enzymes.
Higher protein levels in malt normally signify high levels of alpha-amylase enzymes, but lower levels of the debranching enzyme limit dextrinase which breaks down alpha-1.6 glucosidic bonds and secures desirable wort fermentability. Lower levels of limit dextrinase can also lead to higher levels of unfermentable starch and reduced mash filtration speeds. This reduction in fermentable sugars in the mash leads to lower wort fermentability and poor beer attenuation. Failure to convert dextrins into fermentable sugars can lead to dextrin haze, altering the appearance and body of the beer. DuPont Diazyme® brewing enzymes help brewers with these issues by maximizing the conversion of starch to fermentable sugars and minimizing residual carbohydrates. This maximizes yield and reduces levels of dextrin haze.
Higher protein levels can also lead to excess levels of FAN potentially causing off flavors and reduced shelf-life. This issue could be solved with higher mashing-in temperatures or by increasing adjunct levels.
Harvests and weather are unpredictable. DuPont brewing enzymes give brewers a competitive edge, delivering optimal extraction and cost-effective production. With brewing enzymes that ensure consistent mashing, improve filtration and maximize the use of raw materials, DuPont enzymes ensure excellent beer – whatever the weather.
If you have questions about this year’s harvest, or how DuPont can help you, our brew masters would love to hear from you.