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Questions and Answers
Diacetyl produces a butterscotch flavor.
Diacetyl produces a butterscotch flavor.
True
Yeast does not metabolize maltose before glucose.
Yeast does not metabolize maltose before glucose.
False
Ethanol is the only type of alcohol produced during fermentation.
Ethanol is the only type of alcohol produced during fermentation.
False
A Specific Gravity of 1.072 would be considered a high gravity wort.
A Specific Gravity of 1.072 would be considered a high gravity wort.
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Ferulic acid is decarboxylated to 4-VG, producing phenolic off-flavor.
Ferulic acid is decarboxylated to 4-VG, producing phenolic off-flavor.
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Excessive filtration and clarification of beer will improve foaming properties.
Excessive filtration and clarification of beer will improve foaming properties.
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Iso-alpha acids have a negative influence on foam.
Iso-alpha acids have a negative influence on foam.
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Genetic mutation in yeast is expected after 100 repitches.
Genetic mutation in yeast is expected after 100 repitches.
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Sweetness in beers is not influenced by sugar content.
Sweetness in beers is not influenced by sugar content.
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People tend to make a decision about the quality of a beer based on the package and label.
People tend to make a decision about the quality of a beer based on the package and label.
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High ethanol content does increase foam stability.
High ethanol content does increase foam stability.
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Nitrogen gas will decrease the foam bubble size.
Nitrogen gas will decrease the foam bubble size.
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Yeast hydrophobicity influences flocculation.
Yeast hydrophobicity influences flocculation.
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The flavor threshold refers to the highest concentration at which a substance becomes detectable.
The flavor threshold refers to the highest concentration at which a substance becomes detectable.
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Proteins that are better at forming foam will keep out proteins that are more foam-stabilizing.
Proteins that are better at forming foam will keep out proteins that are more foam-stabilizing.
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A can is a package that provides 50% resistance to MBT formation.
A can is a package that provides 50% resistance to MBT formation.
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Esters are only produced when the alcohol content is greater than 10%.
Esters are only produced when the alcohol content is greater than 10%.
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Surface tension is unaffected by the amount of carbon dioxide.
Surface tension is unaffected by the amount of carbon dioxide.
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A typical bubble radius in beer foam could be 0.5 mm.
A typical bubble radius in beer foam could be 0.5 mm.
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Nitrogen gas will increase the bubble size of beer foam.
Nitrogen gas will increase the bubble size of beer foam.
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Yeast cell viability is assessed by using methylene blue.
Yeast cell viability is assessed by using methylene blue.
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Adding extra maltotetrose during the stationary phase of fermentation will increase the final sugar content.
Adding extra maltotetrose during the stationary phase of fermentation will increase the final sugar content.
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People make judgments on beer quality based on visual cues before tasting.
People make judgments on beer quality based on visual cues before tasting.
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Higher hydrogen ion concentrations are associated with a sweeter taste in beers.
Higher hydrogen ion concentrations are associated with a sweeter taste in beers.
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No yeast are able to metabolize sugars larger than a disaccharide.
No yeast are able to metabolize sugars larger than a disaccharide.
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A wort with an original gravity of 20 oPlato will speed up fermentation compared to a wort with an original gravity of 1.040 specific gravity (10 Plato).
A wort with an original gravity of 20 oPlato will speed up fermentation compared to a wort with an original gravity of 1.040 specific gravity (10 Plato).
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Fermentation temperature has no influence on the amount of esters synthesized by yeast.
Fermentation temperature has no influence on the amount of esters synthesized by yeast.
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All proteins are foam positive.
All proteins are foam positive.
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The cleanliness of the glass does not affect the foam characteristics of beer.
The cleanliness of the glass does not affect the foam characteristics of beer.
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Iso-alpha acids must bind to metal to cross-link for foam formation.
Iso-alpha acids must bind to metal to cross-link for foam formation.
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Excessive oxygen is beneficial for beer flavor and aroma.
Excessive oxygen is beneficial for beer flavor and aroma.
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Contamination with fusarium can lead to gushing in beer.
Contamination with fusarium can lead to gushing in beer.
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Proteinase A improves foam stability and is produced by yeast.
Proteinase A improves foam stability and is produced by yeast.
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Beer temperature has no influence on foam quality.
Beer temperature has no influence on foam quality.
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Adding hops at different stages during the boil does not change the hop character of beer.
Adding hops at different stages during the boil does not change the hop character of beer.
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Yeast metabolizes maltotriose more efficiently than glucose.
Yeast metabolizes maltotriose more efficiently than glucose.
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Yeast does not reproduce sexually with other yeast cells very often.
Yeast does not reproduce sexually with other yeast cells very often.
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In an experiment, people judged the quality of beers based solely on their flavors.
In an experiment, people judged the quality of beers based solely on their flavors.
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A typical bubble radius could be larger than 5 mm.
A typical bubble radius could be larger than 5 mm.
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Higher alcohols, sulfur compounds, and organic acids are all considered volatile compounds.
Higher alcohols, sulfur compounds, and organic acids are all considered volatile compounds.
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Nucleation sites are crucial for bubbles to foam.
Nucleation sites are crucial for bubbles to foam.
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You would expect significant foam formation from excessive filtration and clarification of beer.
You would expect significant foam formation from excessive filtration and clarification of beer.
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Sourness in beer is directly related to the amount of sugar present.
Sourness in beer is directly related to the amount of sugar present.
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During fermentation, one molecule of glucose produces four molecules of carbon dioxide.
During fermentation, one molecule of glucose produces four molecules of carbon dioxide.
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Yeast can produce more ethanol with increased oxygen availability during fermentation.
Yeast can produce more ethanol with increased oxygen availability during fermentation.
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Yeast can metabolize sugars larger than a disaccharide.
Yeast can metabolize sugars larger than a disaccharide.
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Zinc is one of the minerals that aids in the flocculation process of yeast.
Zinc is one of the minerals that aids in the flocculation process of yeast.
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VDKs can only be controlled by fermentation time.
VDKs can only be controlled by fermentation time.
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Proline is preferred by yeast as an amino acid during fermentation.
Proline is preferred by yeast as an amino acid during fermentation.
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The lag phase occurs at the end of fermentation.
The lag phase occurs at the end of fermentation.
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Diacetyl flavor threshold ranges from 0.1 mg/L to 1.0 mg/L.
Diacetyl flavor threshold ranges from 0.1 mg/L to 1.0 mg/L.
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Fermentation temperature will have no impact on the amount of esters synthesized by yeast.
Fermentation temperature will have no impact on the amount of esters synthesized by yeast.
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Tetra iso-alpha acids enhance the visual appearance of foam in beer.
Tetra iso-alpha acids enhance the visual appearance of foam in beer.
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A can provides 100% resistance to MBT formation.
A can provides 100% resistance to MBT formation.
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Dextrins are highly fermentable by the majority of yeasts.
Dextrins are highly fermentable by the majority of yeasts.
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In addition to proteins, bitter acids help maintain bubbles and promote foam in beer.
In addition to proteins, bitter acids help maintain bubbles and promote foam in beer.
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The radius of the nucleation site has no influence on bubble size in beer foam.
The radius of the nucleation site has no influence on bubble size in beer foam.
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Cleanliness of the glass does not impact foam properties.
Cleanliness of the glass does not impact foam properties.
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All proteins in beer possess foam-positive characteristics.
All proteins in beer possess foam-positive characteristics.
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Yeast metabolic activity will be influenced by the presence of zinc as a key mineral.
Yeast metabolic activity will be influenced by the presence of zinc as a key mineral.
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You smell beer only through direct inhalation without any retro-nasal effect.
You smell beer only through direct inhalation without any retro-nasal effect.
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Organic acids released by yeast help lower the pH during fermentation.
Organic acids released by yeast help lower the pH during fermentation.
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Dosing with carbon dioxide or nitrogen at packaging will decrease foam properties.
Dosing with carbon dioxide or nitrogen at packaging will decrease foam properties.
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High ethanol content does not affect foam stability.
High ethanol content does not affect foam stability.
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Most of the flavor of beer is detected through the nose rather than the tongue.
Most of the flavor of beer is detected through the nose rather than the tongue.
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Bitter acids promote foam and maintain bubbles in beer.
Bitter acids promote foam and maintain bubbles in beer.
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Yeast produces more alcohol during fermentation than respiration.
Yeast produces more alcohol during fermentation than respiration.
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Esters are produced during fermentation, regardless of the alcohol content.
Esters are produced during fermentation, regardless of the alcohol content.
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The CO2 range of finished beer is typically between 0.5 - 2.5 mg/ml.
The CO2 range of finished beer is typically between 0.5 - 2.5 mg/ml.
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Nitrogen gas has a negative influence on foam stability.
Nitrogen gas has a negative influence on foam stability.
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Hordeins contain a lot of hydrophobic amino acids which aids foam stability.
Hordeins contain a lot of hydrophobic amino acids which aids foam stability.
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Study Notes
Fermentation and Beer Production
- Diacetyl creates a butterscotch flavor
- Yeasts metabolize maltotriose, but ethanol isn't the only alcohol produced during fermentation
- Volatile compounds include higher alcohols, sulfur compounds, organic acids, and VDKs.
- One glucose molecule yields two ethanol and two carbon dioxide molecules during fermentation.
- Lager yeast can be used to create ale.
- Many ways exist for using dried yeast.
- Saccharomyces yeasts are primarily responsible for beer alcohol fermentation.
- Brewers use multiple Saccharomyces species for ales and lagers.
- Proline is the least preferred amino acid by yeast.
- Yeast doesn't process maltose before glucose.
- Tips for maintaining pure yeast cultures for repitching include regular microbiological assessment, storing at 4°C, acid washing between pitches, and water sedimentation.
- Calcium and zinc aid in yeast flocculation.
- Genetic mutations in yeast are expected after 100 repitchings.
- Diacetyl flavor threshold in beer is 0.1-1.0 mg/L.
- Specific gravity of 1.072 indicates high-gravity wort.
- Fermentation can produce alcohol content exceeding 8%.
- Pumping oxygen into the fermenter increases ethanol production.
- Ferulic acid decarboxylation forms phenolic off-flavor (POF).
- Most yeasts reproduce asexually.
Fermentation Processes and Factors
- Ethanol production isn't continuous throughout the fermentation process.
- Yeast cells, carbon dioxide, alcohol, and aroma increase during fermentation.
- Ethylhexanoate has a pineapple-like aroma.
- Yeasts don't metabolize glucose and maltose simultaneously.
- Yeast respiration doesn't produce more alcohol than fermentation
- Excessive filtration and clarification do not improve beer foaming properties
- Iso-alpha acids positively impact foam.
- Free fatty acids don't enhance foam.
- Serpin (protein Z) is a foam stabilizer and serine protease inhibitor.
- Foam-stabilizing proteins are effectively kept out by proteins at higher foam-stabilizing capacity.
- Surface tension is dependent on carbon dioxide levels.
- Proteinase A enhances foam stability.
- Relationships between protein content and foam stability are approximately exponential, not linear.
- A typical bubble radius is 0.5 mm.
- Albumin improves beer foam but is rarely used due to allergens.
- Nitrogen reduces beer foam bubble size.
- Foam needs a nucleation point.
- Beer temperature impacts foam.
- More protein creates more foam bubbles.
- Nucleation sites increase beer foam replenishment.
- Hydrogen ion concentration correlates to beer sourness.
- Carbon dioxide creates a tingling mouthfeel.
- Bitterness is due to iso-alpha acids.
- Beer smells via direct and retronasal pathways (through the throat).
- Oxygen levels in beer packaging are minimized to prevent flavor instability.
Yeast, Quality, and Other Factors
- Adding hops affects the character of the beer.
- Yeast cell viability is measured using methylene blue.
- Maltose is the most abundant sugar in wort.
- Yeast can't metabolize sugars larger than disaccharides;
- Extra maltotetrose during stationary fermentation won't improve final content.
- Lipids contribute to yeast cell formation.
- Yeast flocculate at fermentation's end.
- Yeast are more closely related to animals than bacteria.
- Organic acids decrease pH during fermentation.
- Nitrogen/Carbon Dioxide usage during packaging doesn't reduce foam.
- Nitrogen positively influences bubble size,foam color and stability .
- Nitrogen reduces foam size
- Miller Coors uses tetrahops to improve stability.
- Iso-alpha acids and manganese positively influence foam.
- Peptides and propylene glycol alginate may influence foam.
- CO2 levels in finished beer are typically 1.0-5.0 mg/ml.
- More than one foam-positive protein exists in malt.
- High ethanol content does not improve foam stability.
- Beer styles such as Wine can vary by the vintage.
- Beer flavor often comes from the aroma
- Sweetness doesn't correspond directly with sugar content.
- Flavor thresholds impact how significant a flavor is in a beer.
- A can has 100% resistance to MBTs.
- Water, hops, malt, adjuncts, and yeast contribute to beer flavor, as ascertained by lecture.
- There are four main tastes in beer (salty, bitter, sour, sweet)
- Fusarium contamination leads to beer gushing.
- Methyl butanoate leads to a skunky aroma.
- Excessive oxygen in beer has a negative effect.
- Iso-alpha acids bind to peptides to create foam.
- Glass cleanliness impacts foam properties
- Beer quality is defined by consistency and consumer preferences.
- Mouthfeel is impacted by factors that include, nitrogen, saltiness is due to sodium and potassium presence.
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Description
Test your knowledge on the process of fermentation and its crucial role in beer production. This quiz covers various aspects, including yeast metabolism, flavor compounds, and brewing techniques. Understand how different factors influence the brewing process and the characteristics of different yeast strains.
