Mash Infusion and Strike Water Calculatorv1.0.0

Strike water hits a target mash temperature by mixing hot water with room-temperature grain, and Palmer's infusion equation models that thermal exchange to return the water temperature and volume you need. The calculator also handles multi-step infusion mashes, where boiling water is added to raise the mash to each successive rest temperature.

• Select your preferred Unit System from the three options: US Quarts/Pounds/Fahrenheit, US Gallons/Pounds/Fahrenheit, or Metric Liters/Kilograms/Celsius. All inputs and outputs update to reflect the chosen units.
• Enter the total Grain Weight for your recipe. The calculator accepts decimals (10.5), fractions (21/2), and mixed numbers (10 1/2).
• Choose a Water Volume Entry method. Select Mash Water/Grain Ratio to enter a ratio (common values range from 1.0 to 2.0 quarts per pound or 2.0 to 4.0 liters per kilogram). Alternatively, select Strike Water Volume to enter an exact volume directly.
• Set the First Rest Temperature to your target mash temperature. Common saccharification rest temperatures range from 148 to 158 degrees Fahrenheit (64 to 70 degrees Celsius).
• Enter the current Grain Temperature, which is typically room temperature (around 68 to 72 degrees Fahrenheit or 20 to 22 degrees Celsius).
• Adjust the Boiling Temperature if you are brewing at altitude. At sea level, water boils at 212 degrees Fahrenheit (100 degrees Celsius). Reduce by approximately 1 degree Fahrenheit per 500 feet of elevation.
• Open Settings to adjust Mash Tun Heat Loss, which accounts for heat absorbed by your mash tun walls. A typical value is 2 to 5 degrees Fahrenheit. Set to 0 if you thoroughly pre-heat your tun. Enable Show step-by-step formulas to view the derivation of each calculation.
• For multi-step mashes, click Add Rest Step to add additional target temperatures. The calculator determines how much boiling water to add at each step to reach the new target. Remove any step by clicking its Remove button.
• The underlying formula is: Strike Water Temperature = (0.2 / R) x (T_target - T_grain) + T_target + TunLoss, where R is the water-to-grain ratio in quarts per pound and 0.2 is the specific heat of grain relative to water.

Mash schedules depend on hitting each rest temperature precisely, and strike water that is a few degrees off shifts the enzyme activity that sets a beer's fermentability and body. A single-infusion ale and a multi-step lager both start from the same calculation of how much water at what temperature to add.

• Single Infusion Mash: Determine the exact strike water temperature for a straightforward saccharification rest at 152 degrees Fahrenheit with 12 pounds of grain and a 1.25 quarts-per-pound ratio.
• Multi-Step Infusion Mash: Plan a traditional German-style mash with a protein rest at 122 degrees Fahrenheit, a beta-amylase rest at 146 degrees Fahrenheit, and a mash-out at 168 degrees Fahrenheit. Calculate the boiling water additions needed at each step.
• Brew in a Bag (BIAB): Use a higher water-to-grain ratio (such as 2.0 quarts per pound or higher) and set the mash tun heat loss to 0 since the kettle is already heated. Find the precise strike temperature for your full-volume mash.
• Altitude Brewing: Adjust the boiling temperature downward for high-altitude locations and see how it affects infusion step calculations. A brewer at 5,000 feet would set the boiling temperature to approximately 202 degrees Fahrenheit.
• Decoction Alternative: Instead of pulling and boiling portions of the mash, use infusion additions to step through temperature rests. Compare the required water volumes to decide between infusion and decoction techniques.
• Recipe Development: Test different water-to-grain ratios to understand how thinner or thicker mashes affect strike water temperatures and total mash volume. Optimize ratios for your specific mash tun capacity.
• Homebrew Education: Enable the step-by-step formula display to study Palmer's equation and understand the thermal relationship between grain, water, and target temperature. Use the calculator as a teaching aid for new brewers.