Brewer Brewing Process & Techniques Flashcards

What is the primary purpose of a vorlauf (recirculation) step during lautering?

Answer: To clarify the wort by filtering it through the grain bed

Vorlauf recirculates cloudy initial runnings back through the grain bed to establish a clear filter layer of husks before collecting wort.

During wort boiling, what is the primary chemical reaction responsible for malt-derived flavor development?

Answer: Maillard reaction between amino acids and reducing sugars

The Maillard reaction between amino acids and reducing sugars during the boil produces melanoidins and complex flavor/color compounds.

Which technique is used to achieve a cold break during wort chilling?

Answer: Adding Irish moss late in the boil and rapidly chilling to below 60°F

Adding fining agents like Irish moss late in the boil and then rapidly chilling promotes aggregation and precipitation of proteins (cold break).

What is diacetyl rest and when is it performed?

Answer: A brief temperature rise near the end of fermentation to allow yeast to reabsorb diacetyl precursors

A diacetyl rest raises beer temperature to 58–68°F near terminal gravity, allowing yeast to reabsorb acetolactate and convert it to off-flavor diacetyl and then reduce it.

In all-grain brewing, what is the typical ratio range for water-to-grain (mash thickness) expressed in quarts per pound?

Answer: 1.25–2.0 qt/lb

A mash thickness of 1.25 to 2.0 quarts of water per pound of grain is the standard range, balancing enzyme activity and lauter efficiency.

Which type of hop addition contributes primarily to bitterness rather than aroma?

Answer: Bittering hop addition at the start of the 60-minute boil

Bittering hop additions at the beginning of a full boil undergo maximum isomerization of alpha acids, contributing most of the beer's measured IBUs.

What is the function of a whirlpool step after the boil?

Answer: To concentrate hop oils, proteins, and trub into a central cone for separation

Whirlpooling creates a vortex that deposits hop material, proteins, and trub into a compact cone at the kettle center, facilitating clear wort runoff.