In April 2019, the Rahr Technical Center completed a study on mill settings for customers who purchase pre-milled malt from RahrBSG. The study was first carried out in both lab and brewery settings, and ultimately in commercial brewery trials. Results indicate that – as expected –  a finer grind potentially provides more extract yield; however this may not be beneficial to all breweries in overall terms.

Some key takeaways from the results:

• Brewery tests showed that tightening the mill settings from the equivalent of RahrBSG’s standard spec (34/32) to a narrower setting (34/20) gave approximately 5-6% more brewhouse yield, but also extended the lautering time by more than 20 minutes per batch.
• The increase in extract yield is not necessarily all fermentable sugars.
• No significant difference was observed in the triangle sensory test between brewery wort samples from the two different mill settings.

Find the full results here on the Brewing Techniques page of our Resources section.