The Brewer

The Ultimate Guide to Brewing Hefeweizen

Hefeweizen: The Bavarian Breakfast Beer

Hefeweizen (literally “Yeast Wheat”) is arguably the most distinct beer style in the world. Pouring a cloudy, glowing gold with a towering head of foam, it smells of bananas, cloves, bubblegum, and fresh bread.

It is a style defined by yeast character. Unlike IPAs driven by hops or Stouts driven by roasted malt, the soul of a Hefeweizen is created during fermentation.

This guide will teach you how to manipulate chemistry to control the balance between Isoamyl Acetate (Banana) and 4-Vinyl Guaiacol (Clove).

The Guidelines (BJCP 10A)

  • Original Gravity (OG): 1.044 – 1.052
  • Final Gravity (FG): 1.010 – 1.014
  • ABV: 4.3% – 5.6%
  • IBU: 8 – 15 (Very low)
  • SRM: 2 – 6 (Straw to Gold)

The Grain Bill: Wheat is King

German law requires a Weissbier to contain at least 50% malted wheat. The rest is typically Pilsner malt.

A Typical Bill

  • 50-70% Wheat Malt: Provides protein for the massive head, cloudiness, and a bready/creamy texture. Wheat has no husk, so beware of stuck mashes (use Rice Hulls!).
  • 30-50% Pilsner Malt: Provides the enzymes needed to convert the starches in the wheat.
  • Optional: A touch (1-2%) of Melanoidin malt or CaraMunich can simulate a decoction mash flavor, but traditionalists avoid crystal malts.

The Secret Sauce: Ferulic Acid Rest

To get the signature Clove flavor (4-Vinyl Guaiacol), you need a precursor called Ferulic Acid. Ferulic acid is bound to the malt structures. To release it, you must perform a specific mash step.

  • The Rest: Hold the mash at 109°F - 113°F (43°C - 45°C) for 15–20 minutes.
  • The Enzyme: This temperature activates ferulic acid esterase.
  • The Result: Higher levels of ferulic acid in the wort, which the yeast will later convert into clove phenol.

Tip: If you hate clove and want a “Banana Bomb,” skip this step and mash in directly at 152°F (67°C).

Yeast Management: Banana vs. Clove

This is where the magic happens. The yeast strain and fermentation temperature dictate the profile.

The Strains

  • Weihenstephan 3068 (Wyeast 3068 / White Labs WLP300): The gold standard. Perfectly balanced, vigorous, and creates that classic “cloud.”
  • WLP380 (Hefeweizen IV): More phenolic (clove/spice), less banana. Good for darker Weizens.
  • Danstar Munich Classic (Dry): Surprisingly excellent dry yeast that mimics 3068 well.

Controlling Esters (Banana)

Isoamyl Acetate (Banana) is an ester. Stressing the yeast promotes ester production.

  • To INCREASE Banana:
    • Underpitch slightly (stress the yeast).
    • Ferment warmer (68°F - 72°F / 20°C - 22°C).
    • Use an “Open Fermenter” (reduced hydrostatic pressure promotes esters).
  • To DECREASE Banana (and increase Clove/Cleanliness):
    • Pitch a healthy starter.
    • Ferment cooler (62°F - 64°F / 17°C - 18°C).

The Mash: Infusion vs. Decoction

Single Infusion (The Easy Way)

Mash at 152°F (67°C) for 60 minutes.

  • Pros: Fast, simple.
  • Cons: Less malt complexity, lighter body.

Decoction (The Traditional Way)

This involves removing 1/3 of the thick mash, boiling it, and returning it to the main tun to raise the temperature.

  • Why do it? The boiling creates Maillard reactions (caramel/toasty notes) and breaks down protein for better foam.
  • Flavor: It adds a “richness” that is hard to define but easy to taste.

Water Profile

Water should be fairly soft, but not distilled.

  • Calcium: 50-75 ppm (for yeast health).
  • Chloride: Moderate (helps mouthfeel).
  • Sulfate: LOW (<50 ppm). You do not want to accentuate hop bitterness.
  • pH: Critical. Mash pH should be 5.2–5.4.

Hops: The Silent Partner

Hops are an afterthought in Hefeweizen. You just need a small bittering charge at 60 minutes to balance the sweetness.

  • Varieties: Hallertauer Mittelfruh, Tettnanger, Perle.
  • Schedule: Just one addition at 60 min. No flavor or aroma hops.

Fermentation Schedule

  1. Pitch at 64°F (17°C).
  2. Free Rise: Allow the temp to rise to 68°F (20°C) over the first 48 hours.
  3. Finish: Hold for 5-7 days.
  4. No Secondary: Do not transfer to secondary. You want the yeast in suspension.
  5. Packaging: Keg or bottle immediately. Hefeweizen is best drunk fresh (within 6 weeks).

Carbonation: The Sparkle

Hefeweizen needs high carbonation.

  • CO2 Volumes: 3.0 – 3.5 volumes.
  • Effect: The high gas levels drive the aromatics out of the glass and provide a sharp “bite” ( carbonic bite) that cuts through the creamy body.
  • Bottling: Use heavy bottles (traditional Weizen bottles) to handle the pressure.

Troubleshooting

  • Too Sour? You might have picked up a lactobacillus infection (common since wheat beer has no hop preservative). Or you mashed too long at low temps.
  • No Banana? Fermented too cold or pitched too much yeast.
  • Stuck Sparge? You forgot the Rice Hulls!

Summary Recipe: “Bavarian Dream”

  • Grain: 55% Wheat Malt, 42% Pilsner, 3% Acidulated Malt.
  • Mash: Ferulic Rest (110°F/20min) -> Sacch Rest (152°F/45min) -> Mash Out.
  • Hops: Hallertauer to 12 IBU at 60 min.
  • Yeast: Wyeast 3068.
  • Ferm: 64°F rising to 68°F.

Brewing a great Hefeweizen is a test of process control. Master the Ferulic Rest and fermentation temperature, and you’ll have a beer that rivals the best of Munich.