CFPS Brewing Ingredients and Process 1 — Questions and Answers
Question 1: What is the primary purpose of the mash in brewing?
- To convert starches in malted grain into fermentable sugars using amylase enzymes (Correct answer)
- To boil the wort and sterilize it
- To add hops and extract bitterness
- To pitch yeast and begin fermentation
Correct answer: To convert starches in malted grain into fermentable sugars using amylase enzymes
During mashing, crushed malt is mixed with hot water, activating alpha- and beta-amylase enzymes that break down starch chains into fermentable maltose and dextrins.
Question 2: What is the role of humulone (alpha acids) in hops?
- Alpha acids are isomerized during the boil to produce bitterness in beer (Correct answer)
- Alpha acids provide floral and citrus aroma directly
- Alpha acids act as a preservative without contributing bitterness
- Alpha acids are responsible for the orange and red color in IPAs
Correct answer: Alpha acids are isomerized during the boil to produce bitterness in beer
Humulone and other alpha acids are converted to iso-alpha acids during wort boiling, and these iso-alpha acids are the primary source of hop bitterness in beer.
Question 3: What does 'attenuation' measure in fermentation?
- The percentage of fermentable sugars converted to alcohol and CO2 by yeast (Correct answer)
- The total bitterness units contributed by hops
- The color depth of the finished beer
- The rate of CO2 production per hour
Correct answer: The percentage of fermentable sugars converted to alcohol and CO2 by yeast
Attenuation (specifically apparent attenuation) measures how much of the original extract (sugars) has been consumed by yeast, calculated as the drop from original to final gravity as a percentage.
Question 4: Which water mineral most directly influences hop bitterness perception, making it seem sharper and drier?
- Sulfate (SO4) (Correct answer)
- Chloride (Cl)
- Calcium (Ca)
- Magnesium (Mg)
Correct answer: Sulfate (SO4)
Sulfate ions accentuate and sharpen hop bitterness, making it seem drier and more crisp, which is why Burton-on-Trent water (high sulfate) is famous for producing assertively bitter pale ales.
Question 5: What is the Maillard reaction in brewing?
- A non-enzymatic browning reaction between amino acids and reducing sugars that creates color and complex flavors in malt (Correct answer)
- The enzymatic conversion of starch to sugar during mashing
- The isomerization of alpha acids to iso-alpha acids during boiling
- The reaction between yeast and oxygen during fermentation
Correct answer: A non-enzymatic browning reaction between amino acids and reducing sugars that creates color and complex flavors in malt
The Maillard reaction occurs during malting kilning and wort boiling, producing melanoidins that contribute amber-brown color and complex bready, toasty, and caramel flavors.
Question 6: What is the primary difference between 'top-fermenting' and 'bottom-fermenting' yeast?
- Top-fermenting ale yeasts work best at warmer temperatures (60–75°F) while bottom-fermenting lager yeasts prefer cold (35–55°F) (Correct answer)
- Top-fermenting yeast produces no alcohol
- Bottom-fermenting yeast is always wild
- Top-fermenting yeast sinks during fermentation
Correct answer: Top-fermenting ale yeasts work best at warmer temperatures (60–75°F) while bottom-fermenting lager yeasts prefer cold (35–55°F)
Saccharomyces cerevisiae (ale yeast) ferments at warmer temperatures and rises to the top, while Saccharomyces pastorianus (lager yeast) works at cold temperatures and settles to the bottom.
CFPS Brewing Ingredients and Process 1
What is the primary purpose of the mash in brewing?