"Keeping cool” is not a lightly used phrase for brewers of beer; instead, it is critical for business. Craft brewer Bell’s Brewery understands that subtle differences in batch-to-batch brewing temperatures, particularly during primary and secondary fermentation stages, can affect the taste, color and aroma of beer. The Kalamazoo, Mich.-based brewer, which has an annual production of 90,000 barrels, understands that just a few degrees too high means yeast will produce larger amounts of ester-based components. And, even when present at part per quadrillion levels, this can have a profound effect on flavor.
To ensure consistent brewing temperatures, Bell’s selected Dowfrost inhibited-propylene glycol from Dow Chemical Co., Midland, Mich., as a secondary coolant for its brewery operations. The fluid will help ensure the consistent temperature control needed in making quality beer.
For brewing beer, a 25 to 45 percent solution of Dowfrost typically is used because it provides dependable temperature control at lower temperature capabilities than water. Typically the fluid is chilled to 32°F (0°C) and recirculated through cooling coils submerged within a tank or through an external jacket surrounding the tank. This allows Bell’s to control to temperatures +/-1°F throughout the brewing process.
All the components used in Dowfrost are approved by the FDA as direct food substances and are generally regarded as safe. The food-safe corrosion inhibitor used in Dowfrost helps prevent corrosion of metals commonly used for construction of brewery equipment and helps ensure long-term thermal stability. Using a properly inhibited glycol keeps heat transfer surfaces free of corrosion deposits, which in turn helps maintain original design efficiencies. Effective corrosion protection of pipes, pumps, chillers and tanks also ensures smooth operation, reduces maintenance costs and avoids downtime to repair leaks or damage caused by corrosion.