| Introduction |
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Many hundreds
of thousands of BetterBottle's unique PET carboys have been sold
since their introduction in July of 2003. Already widely available
in the US, Canada, Europe, Australia, and New Zealand and
distributed by all the major suppliers of premium wine kits and
wholesalers of home winemaking and brewing supplies, BetterBottle
carboys are clearly performing extremely well.
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| Discussion |
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BetterBottle
PET carboys are made of plastic; however, they are not like
other plastic carboys. First of all, they are made of a special PET
and secondly they are made in a manner that packs the plastic
molecules very tightly and creates a delicate balance between
microcrystaline and amorphous regions.1 They are especialy well suited for
home winemaking and brewing. So, why do rumors that no
plastic is acceptable persist here and there? In the first
place, many people have experienced failures attempting to use
carboys made from types of plastic that are known to be too
permeable to oxygen and to scalp flavors (see
Flavor Scalping). Secondly, the mistaken belief that all plastics are
the same is occasionally reinforced by sporadic reports of failures
involving BetterBottle carboys. Making a good wine or beer is an art
and results do not always meet expectations, regardless of whether
the winemaker or brewer uses a glass carboy or BetterBottle
carboy.
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Yes, BetterBottle PET carboys are
slightly more permeable than glass; however, it would be a
mistake to assume that using a glass carboy will necessarily
guarantee superior results. The minute traces of oxygen that
penetrate BetterBottle PET carboys are incredibly difficult to
measure and insignificant when compared with the amounts of
oxygen diffusing through, or leaking past, many types of
carboy caps and stoppers (especially silicone stoppers),
liquid-filled air locks, and many types of flexible
tubing. Moreover, oxygen diffuses into, and reacts with, wine
and beer so quickly that removing a closure from a carboy,
even briefly, for testing and making adjustments can allow a
relatively large amount of oxygen to enter. Wine and beer
essentially suck up oxygen. And racking from one open carboy
to another open carboy with a siphon, a pretty standard
approach when glass carboys are used, will add a great deal of
oxygen in an uncontrolled manner.
Breakthrough Technology - Exciting new
instrumentation, has made it possible to measure oxygen
concentrations from 0.001% to 25% in closed spaces,
quickly and easily. BetterBottle technicians used
this technology to determine how permeable or leaky
a wide variety of closures and air locks are. Many,
perhaps even most, home winemakers and brewers have been
fermenting and aging under conditions involving considerably
more oxygen than they imagined. Click HERE to
view the report (1.5Mb
PDF). | The uncontrolled, excessive entry of oxygen is
the real problem, because the addition of the micro amounts of
oxygen, depending on the wine or beer, is can be
beneficial.2,3,4 Wineries that ferment many hundreds of
gallons of wine in a single tank may actually prefer polyethylene
tanks, because the volume of wine is so huge compared to the surface
area of their tanks. Polyethylene, or other similarly permeable
material, cannot be used to make fermenters for small batches of
wine and beer, because the volumes are small compared to the surface
area of the fermenters. Using a BetterBottle fermentation system,
even a novice will find it easy to rack or bottle cleanly under
conditions that control oxygen exposure (Use the
Products tab at the top of page to access How-To
Tips).
1 Liu, R Y F.
et al. Crystallinity and Oxygen Transport Properties
of PET Bottle Walls. J. Applied Polymer Science. 2004 Vol.
94,671-677 (Accessed 01/15/12) 2 Kelly, M. and Wollan,
D. Micro-oxygenation of Wine in Barrels. The Australian & New
Zealand Grapegrower & Winemaker 2003, Technical Issue
3 Flecknoe-Brownn, A. Oxygen-permeable polyethylene vessels: a new
approach to wine maturation. Grapegrower & Winemaker March
2005(Accessed 01/15/12) 4 Davis, K., Science trumps tradition at Napa wine-making
facility. Napa Valley Register 10/01/10 (Accessed
01/15/12) | |