October 23, 2018

How to Partial Mash Homebrew

Partial Mash Walkthrough

Northern Brewer's Partial Mash Kits are an excellent way for the extract brewer to take his or her brewing to the next level. By adding a "mini-mash" to standard malt extract brewing techniques, you can create a more complex malt profile and gain access to a wider palette of grains without a big investment in all-grain equipment.

This is a very brief overview of the brewing process for a Northern Brewer partial mash beer recipe kit; it assumes familiarity with basic procedures for brewing beer from malt extract. Detailed instructions (with recipe-specific info like mash temperatures, mash rest duration, etc.) are included with each kit.

In addition to the equipment required for malt extract brewing (boiling kettle, primary fermenter, siphon, etc.), you will need the following to brew our partial mash kits:

  • thermometer with a range that includes 120°-170°F
  • A  mash kettle - a pot with a capacity of at least 4 gallons (the boiling kettle you already have can do double duty)
  • A second pot or kettle with a capacity of at least 2 gallons for heating sparge water
  • large strainer or a nylon mesh bag that can hold up to 5 pounds of wet grain (used to separate the grain from the mash liquid in Step #8)

Upon Receiving Kit:

  • Double-check contents vs. Kit Inventory.
  • Refrigerate liquid yeast.

Before you Brew

  • Prepare yeast for brewing: Incubate liquid yeast "smack packs" and/or prepare a yeast starter.

On Brewing Day:

Grain comes crushed by default, but if you requested uncrushed grain, put it through the mill now.
  1.  For every pound of grain in the recipe, collect 1 quart of water in the mash kettle. This will be the mash water. E.g, 3 pounds of grain = 3 quarts of water.
  2.  Heat mash water to strike temperature. Approximately 10°F warmer than the first mash temperature in the recipe (e.g., if the first mash temperature is 152°F, heat the water to 162°F).
  3.  Add crushed grain to the hot mash water in the pot. Stir well to thoroughly mix the grain in!
  4.  Measure the temperature of the grain-water mixture. It should stabilize within 1-2° of the mash temperature given in the kit inventory. Add cool or hot water as needed to bring it into this range.
  5.  Hold temperature for mash rest. Maintain the mash temperature for the time specified by the kit inventory.
  6.  Collect and heat sparge water. Using the second pot, collect the same amount of water used in Step #1, heat it to 170°F, and hold it at that temperature until it's needed in Step #9.
  7.  Raise temperature to next mash rest. Return the mash kettle to the stove and apply very low heat. Stop heating when the next mash temperature is reached and repeat Step #5. Mash-Out: All kits end with a final mash temperature of 168°F, or “mash-out.” After mash-out, proceed to Step #8.
  8.  Separate the grain from the liquid portion of the mash. Don't spill or waste the liquid, which is now the wort.
  9.  Sparge the grain. Slowly pour the 170°F sparge water through the grain, one quart at a time, until it's gone. Collect the sparge water along with the wort in the boil kettle. Discard the grain.
  10.  Top up the kettle (if needed). Add more water if necessary to achieve your normal boil volume.
  11.  Boil the wort. Boil the wort for 60 minutes with malt extract and hops, chill the wort, and top up in the fermenter to a final volume of five gallons, exactly as you would for an extract batch.