2nd midterm Flashcards
cold bottles entering tunnel pasteurizier is used to cool the
water that is used to cool the bottles at the discharge end
flash pasteurizer is heated to
70 C for a very short amount of time
cooling section of a flash pasteurizer
has no impact on the heat up section of the in-coming beer
cooling section of a flash pasteurizer
has no impact on the heat up section of the in-coming beer
hollow fibre hydrophobic membranes both
add and removes gasses from beer
total pressure equals the sum of partial pressure of individual components.
Daltons Law
At a constant temperature(for a given mass of gas) volume is inversely proportional to pressure.
Boyle’s Law
Nitrogen is 120x
less soluable than CO2
solution for long draft lines are
Installation of beer pump
Mixed gas of nitrogen and CO2
balanced draft system is when
resistance to the flow from keg to tap is appox equal
Properly adjusted system should pour at
1 gal/ min
In a flash pasteurizer as much as ____% of the heat content is recovered
94-95%
The last heating zone in a tunnel pasteurizer before the holding section is
Superheat Zone
Henry’s Law P=H*X
p=pressure of gas
h=henry;’s constant for a given gas
x=molar fraction of gas
Henry’s law defines in which a gas distributes itself between the gas phase and the solution phase
true
At a constant pressure (for a gven mass of a gas) the volume of gas is directly proportional to the temperature.
Gay-Lussac’s Law
Nitrogen is significantly
less dense than CO2
The purpose of a choker line is
to equal the gas pressure and distance to make pouring a beer easy/ without foam
properly adjusted draft system should take ____sec to fill a 1.89L growler
30 seconds
Peak production temperature achieved in a tunnel pasteurizer is
around 60 C
failure pressure for tunnel pasteurizer with small packages
non return bottle=10 bar
Cans= 6 bars
Returnable bottle=12 bar
P x V = n x R x T
Combined gas law
Decimal reduction time(D) is the time needed at a given temperature to
inactivate 90 % of the viable microbrail population
why things can’t grow in beer
anaerobic environment
beer spoilage orangisms are
not pathogenic
rank the pressure drop in common beer lines from low to high
1=Barrier tubing
2=polyethylene
3=polypropylene(vinyl)
two main componets to tunnel pasteurizers
- water spray and circulation systems
- package transport
cold spot in a bottle and can is
the centre bottom quarter
two transfer systems for tunnel p
- walking beams(used in the past)= lift move forward and down. less common due to the containers stability to stay upright
- continuous belt= plastic polypropylene conveyor, more precise control
pasteurizer prone to
corrosion and slime growth
advantages of tunnel pasteurizer
most reliable and efficient, minimal effecot on product, no risk of reinfection
adverse effect of flavour
high internal pressure
high operating cost(energy and water)
high capital and installation
large floor area
Disadvantage to tunnel pasteurizer
flash P= bread like flavour can develop when
high temperature occurs
Design of Flash P
Heat regeneration
heating
holding cell
final cooling
Plate failure can occur and you must protect…
pasteurizer from un pasteurized, use of pump to increase pressure on the pasteurized side is possible (0.5 bar higher min)
typical range to keep gas in solution is
1-1.5 bar
Wetting pressure is
2-8psi
BBT for nitro beer require at least
2 bar or 30 psi
beer must be stored and served at the
right temp and idela gas pressure to provide correct carb level
