Flavor, Haze, Foam Flashcards
(34 cards)
Which hop variety will have the most bittering potential?
Simcoe will have the most bittering potential due to the lowest iso-cohumulone.
What is “umami” in common terms?
Savory
Drinkability
What is “kokumi” in common terms?
Rich tasting
Delicious
What flavor characteristics are attributed to Sulfate?
Dryness and astringency
What flavor characteristics are attributed to Chloride?
Fullness and body
What is a flavor unit?
Total measured/Flavor theshold
(60 mg DMS/30 mg threshold = 2 flavor units)
Excess FAN results in more or less higher alcohols produced
More
Stronger wort increases or decreases ester formation
Increases
A temperature rise of 3-4 degress on fermentation will have what effect on VDKs and higher alcohols?
Will increase rate of utilization for VDKs
Will increase production of higher alcohols
What is the commercial enzyme “Maturex” (Acetolactate decarboxylase) used for?
To prevent the production of diacetyl
The Synebrychoff method is a much faster method (compared to the natural process) to remove VDKs from green beer. Why is it not used in industry?
It is too complex to use practically.
Ferment, centrifuge, heat green beer to 80C for 20 minutes, cool, flow through immobilized yeast
Which VDK is produced by pediococcus? What is often the cause of this contamination?
Pediococcus produces diacetyl but not pentanedione.
It is a contamination often caused by dirty draft dispense lines.
What reaction is methionine sulphoxide reductase enzyme used for?
Where is this enzyme found?
Converts DMSO to DMS.
It is found in both ale and lager yeasts.
Lager fermentations will convert more DMSO to DMS due to lower temperatures.
Perceived DMS increases or decreases with the concentration of 2-Phenyl ethanol (2-PE)?
Decreases
Which cereal grain does Ferulic acid come from?
Wheat cell walls
What is a better method for measuring sourness than pH?
Titratable acidity gives a better indication of sourness
What is invisible haze? How do you avoid measuring invisible haze?
Haze that can’t be seen but there are particles in solution that will deflect light to the 90 degree detector.
Detect forward scatter at 13 or 30 degrees to avoid measuring the invisible haze.
What is chill haze?
A haze that forms when beer is chilled to 0C but which returns to solution when the beer is returned to 20C.
Particle size of 0.1 to 1 micron
What is permanent haze?
Haze that is present at all temperatures.
Particle size of 1 to 10 microns
What is the method of chill haze formation proposed by Karl Siebert?
At low temps, 2 ended polyphenols will bridge between proline molecules to form long chains resulting in haze.
Once the temp increases, the molecules break apart.
Where do the haze forming proteins originate?
Mostly hordein derived
Rich in proline
Albumin and globulin also in chill haze but only after those derived from hordein
What is PVPP and what is it used for?
Polyvinylpolypyrrolidone
Binds polyphenols and tannins because it has a similar structure to proline. Removes haze as a result.
Comes as a single use powder or a regenerable sheet
What is silica gel and what is it used for?
Highly purified sand that is processed into a gel.
Selective for haze forming proteins.
Can be used as a tank dosing method or as a filter aid substitute.
What is tannic acid and what is it used for?
It increases precipitation of solids in beer to remove haze.
Dosed in-line on the way to the filter.
