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Extending the shelf life of commercial canned wines through manipulation of transition metals content
Neil Scrimgeour, Kieran Hirlam, Eric N. Wilkes1 The Australian Wine Research Institute, PO Box 197, Glen Osmond (Adelaide) SA 5064, Australia
Corresponding author’s email: [email protected]
Summary Commercial canned wines commonly display
reductive characters from hydrogen sulfide (H2S; ‘rotten egg’) and methanethiol (MeSH; ‘cooked vegetable’), often within 3-6 months.
Transition metals, such as copper (Cu), can speed up the formation of these stinky aromas, especially in a low oxygen environment.
Aluminium (Al), released from the can interior during storage, may also affect sulfide formation.
Finding a practical solution to the problem
Copper is often found bound to sulfides in commercial wines.
Cross-linked polymers (CLPs) can be used to lower copper concentration.
This could result in lower levels of residual sulfides in the wines.
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0
2
4
6
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cont
rol 2
w
cont
rol 4
w
cont
rol p
H 3.
8 2w
cont
rol p
H 3.
8 4w
Al fo
il 2w
Al fo
il 4w
Al fo
il - h
igh
TPO
2w
Al fo
il - h
igh
TPO
4w
Al F
oil +
Cu
2w
Al F
oil +
Cu
4w
Al fo
il pH
3.8
2w
Al fo
il pH
3.8
4w
pero
xide
+ A
l foi
l 2w
pero
xide
+ A
l foi
l 4w
strip
ped
+ Cu
2w
strip
ped
+ Cu
4w
strip
ped
+ Al
foil
2w
strip
ped
+ Al
foil
4w
strip
ped
+ Cu
+ A
l foi
l 2w
strip
ped
+ Cu
+ A
l foi
l 4w
Conc
entr
atio
n (µ
g/L)
Average of hydrogen sulfide Average of methanethiol
Testing the theory with bench-scale trials
Addition of aluminium (metal) to wine elevates H2S levels within four weeks.
Impact of aluminium on H2S formation appears to be less when pH is higher, oxygen (TPO) is higher and SO2 is lower.
Resulting H2S levels are lower when copper is removed using CLP treatment, even when aluminium (metal) is present.
Minimal impact is seen on MeSH levels following the CLP treatment in this environment.
Evidence of aluminium exposure from the can interior surface
Future work
Confirm impact of lowering copper concentrations in a range of wine matrices
Evaluate extent of impact when oxygen and SO2content are varied
Matched funding for this work has been provided by Food Innovation Australia Limited, Industry Growth Centre for Food and Agribusiness.
Food Innovation Australia Limited (FIAL) is an industry-led, not-for-profit focused on growing the share of Australian food in the global marketplace.
