Master Brewer Certification Brewer Raw Materials & Ingredients 2 — Questions and Answers
Question 1: Which barley variety is classified as a two-row type and widely preferred for American lager production?
- Maris Otter
- Harrington (Correct answer)
- Golden Promise
- Triumph
Correct answer: Harrington
Harrington is a two-row barley cultivar developed in North America and long favored by American craft and commercial lager brewers for its clean fermentable profile.
Question 2: What is the primary role of beta-glucanase enzyme activity during mashing?
- Converting starches to fermentable sugars
- Breaking down beta-glucan gums that cause lautering problems (Correct answer)
- Denaturing proteins to clarify wort
- Producing ferulic acid for downstream yeast use
Correct answer: Breaking down beta-glucan gums that cause lautering problems
Beta-glucanase degrades beta-glucan cell wall polysaccharides found in undermodified or high-adjunct malt, preventing viscous wort and stuck lautering.
Question 3: A brewer notices persistent haze in finished beer traced to high-molecular-weight proteins binding with polyphenols. Which malt parameter most directly predicts this risk?
- Diastatic power
- Kolbach index (S/T ratio) (Correct answer)
- Free amino nitrogen (FAN)
- Wort color (Lovibond)
Correct answer: Kolbach index (S/T ratio)
The Kolbach index measures the degree of protein modification; a low S/T ratio indicates poorly modified malt with excess high-MW protein prone to chill haze formation.
Question 4: Myrcene, linalool, and geraniol are important hop oil compounds. Which one is most associated with a floral, citrusy aroma surviving dry hopping?
- Myrcene
- Linalool (Correct answer)
- Farnesene
- Caryophyllene
Correct answer: Linalool
Linalool is a stable, water-soluble terpene alcohol that persists through fermentation and dry hopping, contributing floral and citrus notes to beer.
Question 5: Crystal/caramel malts develop their characteristic sweetness and color through which process during production?
- Kilning at high temperatures without prior steeping
- Stewing wet green malt then kilning to fix sugars (Correct answer)
- Extended cold steeping followed by rapid drying
- Drum roasting fully dried base malt
Correct answer: Stewing wet green malt then kilning to fix sugars
Crystal malt is made by stewing green (undried) malt at 65–75°C to convert starches inside the kernel, then kilning to caramelize those sugars in place.
Question 6: Which water ion at elevated concentrations most strongly accentuates hop bitterness perception?
- Calcium (Ca²⁺)
- Magnesium (Mg²⁺)
- Sulfate (SO₄²⁻) (Correct answer)
- Bicarbonate (HCO₃⁻)
Correct answer: Sulfate (SO₄²⁻)
High sulfate levels (above ~150 ppm) accentuate and dry out hop bitterness, making it more assertive and crisp on the palate.
Question 7: Corn grits used as a brewing adjunct must be gelatinized before mashing. What is the approximate gelatinization temperature range for corn starch?
- 45–55°C (113–131°F)
- 62–72°C (144–162°F) (Correct answer)
- 72–80°C (162–176°F)
- 85–95°C (185–203°F)
Correct answer: 62–72°C (144–162°F)
Corn starch gelatinizes in the range of approximately 62–72°C, which overlaps with normal mash temperatures only if a cereal mash or pre-cooking step is used.
Master Brewer Certification Brewer Raw Materials & Ingredients 2
Which barley variety is classified as a two-row type and widely preferred for American lager production?