Master Brewer Certification Brewer Quality Control & Testing 2

Question 1

Which method is most appropriate for detecting wild yeast contamination in a commercial brewery?

Accepted Answer

Lysine medium plating

Answer

Lysine medium inhibits Saccharomyces cerevisiae but supports wild yeast growth, making it selective for detecting wild yeast contaminants.

Question 2

A brewer notices haze formation in a filtered bright beer that was initially clear. What is the most likely cause?

Accepted Answer

Protein-polyphenol chill haze development

Answer

Protein-polyphenol complexes form chill haze when beer is cold, appearing as haze that may be reversible or permanent depending on the degree of bonding.

Question 3

What does a Forced Fermentation Test (FFT) allow a brewer to determine?

Accepted Answer

Terminal gravity a wort will achieve when fully fermented

Answer

An FFT uses excess yeast under warm conditions to rapidly ferment a wort sample to its terminal gravity, predicting the final attenuation before the main batch is complete.

Question 4

Which unit is used to express the bitterness level of a finished beer?

Accepted Answer

IBU (International Bitterness Units)

Answer

IBU (International Bitterness Units) measures the concentration of isohumulones in beer in parts per million (mg/L), representing perceived bitterness.

Question 5

What is the purpose of a beer flavor stability test using Electron Spin Resonance (ESR)?

Accepted Answer

Measuring free radical levels to predict oxidative staling shelf life

Answer

ESR measures free radical concentration in beer, providing an early predictor of oxidative staling potential and estimated flavor shelf life.

Master Brewer Certification Practice Test

Master Brewer Certification Practice Test

Master Brewer Certification Brewer Quality Control & Testing 2