15. Finishing and Packaging Flashcards
What is used for protein stabilization?
Fining with bentonite
How does CHARCOAL work as fining agent?
What type of wine is it commonly used for and why must care be taken?
- removes brown colors + some off-odors
- used to create Pale Cream Sherry
- eaily removes desirable aromas + flavors if over-used.
Why is oxygen management one of the most important considerations when bottling?
What happens if there is too much / too little?
- amount of oxygen in final container determines shelf-life+expected development of wine.
- too much oxygen = premature browning + oxidized characters (loss of fruit, bruised fruit notes)
- too little oxygen = reductive characters e.g. onion, rotten egg aromas.
What are the 4 ways to clarify post-fermentation?
1) sedimentation
2) centrifugation
3) fining
4) filtering
In the context of HACCP, what is an example of a specific hazard and a preventive action plan to handle it?
e.g. In a bottling line there is a hazard of glass breaking + ending up in a bottle of wine = hazardous to customer.
Preventive Action Plan = have a detection system to identify the broken bottle and push out the next 3 neighboring bottles automatically.
What are the 2 main exceptions to the overwhelmingly preferred option of glass bottles for packaging wine?
1) producer markets (e.g. France) where consumers collect wine directly from a local winery in plastic containers for early drinking.
2) bag-in-box markets (e.g. Sweden) where this packaging makes up 50%+ of consumption.
Explain how the CONTACT PROCESS works (2):
Pros (4)?
- addition of potassium bitartrate to wine speeds up crystallizing process.
- crystals are filtered out before bottling.
- quicker, continuous, cheaper, more reliable.
Explain how ELECTRODIALYSIS works:
Costs / Pros (3)?
- charged membrane is used to remove selected ions.
High initial investment, but cheaper in the long run.
Uses less energy + faster.
Removes both potassium + calcium ions
What is HACCP (3)?
- Hazard Analysis of Critical Control Points
- a process in which the company identifies all the possible hazards that could affect final wine quality
- for each hazard, an HACCP document will state how serious it is and how it can be prevented and corrected
What are advantages of bag-in-box packaging (5)?
- flexible pour size (1 or more glasses)
- protection from oxygen once opened (bag collapses around remaining wine)
- range of sizes,
- easy to store
- low environmental impact (light to transport + recyclable)
How does ISINGLASS work as fining agent (2)?
Why must care be taken when using it (2)?
- removes phenolics that contribute undesirable colors + bitterness
- protein collagen derived from fish bladders that clarifies white wine = bright appearance.
- over-use = risk of protein haze + fishy smell.
- not suitable for vegetarians.
What is bentonite?
How does it affect wine (3)?
Form of clay used as a fining agent to absorb unstable proteins/unstable colloidal colouring matter.
- minimal effect on flavor/texture of wine
- leads to some color loss in reds
- produces large amounts of sediment, so some wine is lost during racking.
What causes VA to the point that it’s a fault? (3)
How does it affect the wine?
1) activity of acetic acid bacteria
2) inadequate levels of SO2
3) excess exposure to oxygen
Results in pungent smells of nail varnish/vinegar.
What is pictured below?
What is its purpose?
- Membrane filters used for sterile filtration.
- used to remove yeasts and bacteria in order to render the wine microbiologically stable.
What can reduce the threat of VA? (5)
1) sorting fruit to exclude damaged grapes
2) improving hygiene in winery
3) keeping vessels topped up
4) careful racking (avoiding too much O2 exposure)
5) maintaining adequate SO2 levels
Why is a small amount of CO2 in finished (still) wine sometimes desired?
How can this be achieved (2)?
- some winemakers prefer a tiny spritz to add freshness, esp. for inexpensive, fresh white and rosé wines.
- either manually add CO2 or bottle wine while small amounts of CO2 remain dissolved from fermentation.
What are membrane filters?
What are PROS (2) and CONS (3)?
- filters that catch particles (e.g. yeasts/bacteria) that will not go through pore size of filter
PROS: - ensures that wine is completely clear and microbiologically stable.
- initial invenstment of machinery is low
CONS: - slower than depth (pores are smaller)
- wine must be pre-filtered to not clog
- cartridges are expensive to replace.
Why can a (still) wine have visible bubbles or spritz in the bottle (3)?
- re-fermentation caused by unfiltered yeasts + RS in bottle.
- conscious stylistic choice e.g. Muscadet sur lie or Vinho Verde.
- conscious producer decision to preserve/enhance freshness.
Describe briefly the Chain of Certification from ISO to Consumer (5):
1) ISO sets the internationally recognized standards.
2) Certification body conducts the audit.
3) Wine company conducts its own audit to ensure conformity.
4) Retailer buys wine with assurance from external audit.
5) Customer buys wine with assurance.
What is the total package oxygen of a wine a combination of? (4)
1) amount of dissolved oxygen in wine
2) oxygen in head space
3) amount of oxygen in cork/other closure
4) oxygen transmission rate (OTR) of cork/closure
What is diatomaceous earth (2)?
2 AKAs?
How does it add cost to a wine?
- most common form of depth filtration
- soft sedimentary rock that is processed into pure silica, and therefore inert.
AKA “DE” / “Kieselguhr”
DE must be disposed of responsibly = additional cost.
What is the difference between DEPTH FILTRATION and SURFACE FILTRATION?
DEPTH: method of filtration that traps particles in the depth of its material that forms the filter, e.g. Diatomaceous earth, Sheet filters.
SURFACE: method of filtration that stops particles that are bigger than the pore size of the filter from going through, e.g. Membrane filters and Cross-flow filters.
How does EGG WHITE work as fining agent (3)?
What type of wine is it commonly used for and why?
What consideration must be taken when using it?
- Removes phenolics that contribute undesirable color + bitterness.
- used in fresh/powdered form
- high protein content removes harsh tannins + clarifies wine.
- used for high-quality reds because of its gentleness.
- must be noted on the label if sold in the EU due to allergen reasons.
Explain the mechanics of Bag-In-Box packaging:
What considerations must be considered by the manufacturer (3)?
What is the shelf life of a wine packaged this way?
Where are wines packaged this way most successful?
- Flexible, very thin aluminum foil bag (lined w/plastic) housed within a cardboard box.
- needs slightly higher SO2 level to counter oxidation.
- v. low CO2 to avoid bag bulging/bursting.
- high-quality tap is needed to reduce oxygen ingress.
Shelf Life = 6-9 months.
most popular in Australia (where it was pioneered) + Sweden
What influences the number of rackings carried out for a wine (2)?
How does this affect the price of the wine?
What styles of wine are suitable for multiple rackings?
- Depends on size of containers + availability of labor.
- Larger the vessel = more rackings needed
- This adds cost to the wine (sedimentation takes time = wine can’t be sold for a while / labor$$$)
- Therefore, sedimentation/racking is usually only suitable for premium/super-premium wines.
What are advantages of using a natural cork (4)?
What about its image?
- light, flexible, inert, comes from natural/renewable source
- mainly has a positive image in eyes of consumer; opening a bottle w/a corkscrew is seen as part of the enjoyment.
Where and when did bottling wine at the winery become an important means of quality control?
Why did this change happen?
How was wine trasported before this?
Began in Bordeaux in the 1920s as a means of quality control.
This way, the producer could guarantee that the final wine was as intended, not at the mercy of possible blending/alteration.
Before this, wine had been transported in animal skins, terracotta pots and wooden barrels.
What is a drawback of using sorbic acid for microbiological stabalization in wines?
- Some people can smell the effects of sorbic acid at very low levels.
What is surface filtration?
What are they often referred to as?
What are the two types?
- Method of filtration wherein a wine passes through a “surface” w/ a porous membrane to stop particles that are bigger than the pore size from going through.
- referred to as “absolute filters”
- membrane filters and cross flow filters
How does the proportion of wine shipped in bulk compare to that shipped in bottle, both in terms of volume and value?
Marjority of exported wine, both by volume and value, is transported in bottle (60-70% of volume.)
What are the 3 categories of common fining agents?
Give a specific example of each:
1) those that remove unstable proteins (ex. Bentonite)
2) those that remove phenolics that contribute undesirable colour/bitterness (e.g. egg white)
3) those that remove colour and off odour (ex. charcoal)
What are advantages of using a can (5)?
Why does the inside of the can have to be lined w/plastic?
- lightweight,
- robust,
- easy to open,
- impermeable to oxygen,
- recyclable
Plastic is needed to prevent the wine’s acidity from attacking the aluminum.
What are some PROS (2) and CONS (2) of using screwcap closures?
PROS: - Ease of opening, no special tools required.
- No chance of cork taint.
CONS: - Different markets view w/different levels of acceptance (e.g. Australia/NZ/UK are more on board)
- Still seen as synonomous w/cheap wines by some (e.g. USA/China)
Explain the 2 pictures below:
1) Sacks of diatomaceous earth that can be wetted and used as a filter medium.
2) A rotary vacuum filter; wine is sucked by a vacuum from outside the drum => passes through DE to the inside of the drum
What are 3 different circumstances in which wines should/shouldn’t receive post-bottling maturation?
What are the costs involved with post-bottling maturation at the winery?
- Many wines, e.g. Veneto PG based on fresh, fruity flavors, are best consumed within a year of bottling. This is because maturing them results in a los of primary fruit flavors.
- Others (e.g. German Riesling, Vintage Port, First Growth Bordeaux) develop positively for many years and are at their best after a number of years following bottling.
- Some PDOs have bottle-maturation requirements before sale is allowed e.g. Chianti Classico Riserva DOCG.
Post-bottling maturation at the winery increases insurance and storage costs (having/building suitable facilities).
Explain how COLD STABALIZATION works (2):
Costs / Considerations (3)?
- wine is held at cold temps (-4 C / 25 F) so that tartrate crystals form.
- crystals are filtered out before bottling.
Requires equipment and energy$$$ for refrigeration.
Only removes potassium bitartrate, not calcium tartrate.
Fining must occur because colloids can prevent from crystals from forming.
What is the advantage of shipping wine in bottle?
The entire product (wine/bottling/labelling/external packaging) is controlled by the producer.
The ideal closure for a wine bottle has these properties (4):
5 e.g.s of wine bottle closures:
- protects from rapid oxidation
- is inert (doesn’t affect quality of wine adversely)
- easy to remove + re-insert
- cheap, recyclable, free of faults
Natural Cork / Synthetic Cork / Technical Cork / Screwcap / Glass Stopper
Explain how CARBOXYMETHYLCELLULOSE (CMC) works:
Costs / Considerations (3)?
- cellulose prevents tartrates from developing to a visible size.
- widely used on inexpensive whites + rosés
- not suitable for reds due to reaction w/tannins + causes haziness.
- much cheaper.
What is pictured below?
How does it work (2)?
Wine passing through a Sheet Filter.
- wine passes through a sheet of filtering material.
- the more sheets in the filter, the quicker the total amount of wine can pass through because any portion of wine only passes through 1 sheet.
What is depth filtration (2)?
What is the most common form?
- method that traps particles in the depth of the material that forms the filter
- small particles become trapped w/in irregular channels of the filter.
- most common is diatomaceous earth (DE)
Explain what is happening in the picture below (4):
1) A fining agent is added to an unfiltered wine.
2) The fining agent has an opposite charge from the wine colloid, so they attract each other and form a larger solid.
3) This new solid is heavier and falls to the bottom.
4) These solids can now be removed by racking/filtration.
How does a cross-flow filter work?
What are PROS (3) and CONS (1) of using one?
- allows wine to pass through filter while uniquely cleaning surface of filter as it works
PROS: - can filter wine with high load of particles very quickly
- does not clog as quickly as membrane filters.
- no replacement sheets / cartridges / DE to buy or dispose of.
CONS: - machinery is expensive; only suitable for large/well-funded wineries.
