Filteration, pasteurization, packaging, storing

Stability

• micro-biological stability: yeast and bacteria
• non-biologial stability(colloidal stability): chill haze, permanent haze
• flavor stability: keeps fresh, pure flavor, against stale flavor
• foam stability

Filtration

• aim of filtration: remove of suspended particle
• suspended particle:
• micro organism(yeast and bacteria)
• organic haze material(carbohydrate particle and trub-> chill haze, permanent haze)
• non organic haze(calcium oxalate, filter aid)
• disadvantages: 

1. loss of extract, bitter, color, mouthfeel, foam
2. intake of oxygen, component of filter material

• surface filtration vs. depth filtration(industry's favorite)

Types of filter 

• frame
• candle - big company's favorite, use DE coated pipe
• horizontal - use DE coated disk

Filtration media 

• granulated - Kieselguhr(diatomaceous earth), perlite. not eco-friendly
• fibrous(cloth of frame filter) - cellulose
• additives - PVPP(polyvinylpolypyrrolidone), silica gel
• filtration additive: 

1. PVPP forms similar bond to peptidic bond(protein), precipitate tannins the same way as proteins do
2. Silica gel binds haze forming protein 
3. can not use PVPP and silica gel at the same time
4. ishing glass: active with protein and tannins
5. irish moss: active with protein
6. papain: proteolytic enzyme, break down protein

• colloidal instability: the main cause is the interaction between haze forming polyphenols and haze giving proteins(derived from malts and hops)

Alternative filtration

• cross flow: progressed. eco-friendly. not using DE
• separator(centrifuge): micro brewery's favorite. cheap. keep small particles with less loss and more tastes
• Darcy's law=means filter area is the most critical factor

Pasteurization

• pasteurization unit(PU): a dead amount of microorganism when a beer is exposed for 1min at 60 degree Celsius. generally 10~15PU link
• PU=t*1.3932^(T-60)
• t=time in minutes, T=holding temperature
• (ex. 30sec at 72'c) PU=0.5*1.3932^(72-60)=53.48/2=26.74 link
• higher temp with short time=low temp with long time(oxygen warning!)
• flavor: bread like, oxidized, cooked, paper like
• pasteurization accelerates the beer aging
• flash pasteurization=HTST
• highly effective for heat delivery, easy temperature control, automatic system, minimize the risk of flavor, aroma change, energy saving but disinfected and sterilized bottling equipment needed.
• tunnel-microbrewery's favorite. 

Packaging

• glass: re-usable, mechanical stability, inert, no permeability, transparency(for easy inspection), high hygienic quality but hardness, light strike, thermal stress
• plastic: light weight, stability, safe for breaking but permeation, closure, label
• can: light, unbreakable, easy to store and print, no light strike at all but expensive(poorly recycled)
• packaging line: need at least 10 mins gap between each process 

1. dispalletiser
2. unpacking machine
3. bottle cleaning machine
4. empty bottle inspection machine
5. filling machine
6. tunnel pasteurizer
7. labelling machine
8. pacing machine
9. palletiser

Storing

• dark=no skunky 
• cold
• no oxygen=no cardboard
• no move