Researchers led by Helen Hopfer and her colleagues at the Department of Viticulture & Enology at University of California, Davis used chemical analyses with the help of a panel of expert tasters to analyse wine stored at three different temperatures and in different containers. California unoaked Chardonnay provided by Constellation Brands was analyzed in glass bottles with natural and synthetic corks, screw caps and two kinds of bag-in-box containers for three months for the study.
They found the bag-in-box wine to be more vulnerable to warmer storage temperatures than bottled wine. According to a Press Release by the University, while warmer temperatures were responsible for negative changes in all the wines, bag-in-box wines changes were the most pronounced.
Wine in the box temperature was varied from 20°C to 40°C; the aging was significantly faster than the bottled wine. It became darker and developed attributes like sherry, dried fruit and vinegar, according to the report. Researchers also discovered that all wines aged better when stored at 10°C.
“The largest changes were observed with the highest storage temperatures of 40°C, independent of the packaging,” authors wrote, adding that all samples showed signs of oxidation at 40°C, and were described by the sensory panel as ‘oxidized, musty and sulphur’. They were lower in lightness and green colour and higher in yellow. Moreover fruit-related compounds decreased with increasing storage temperatures.
“The way a wine looks, tastes and smells is affected by the way certain compounds react with oxygen,” reportedly said lead researcher Helene Hopfer. She added, "Those reactions speed up at higher temperatures, so differences in the way packaging systems manage oxygen in the container become critically important to aging and stability of wine."
Box wine has certain advantages over bottled wine; it’s easier to ship more quantities than the standard bottle as it takes less space. Obviously one does not need a corkscrew to open them and there are no breakages. Due to their bigger capacity of up to 4 liters or even more, they are quite useful for restaurants and homes as the oxidation is much slower. They have become quite popular in the Nordic countries like Sweden and Norway etc. where the climate is colder.
Although not totally absent, bag-in-box wines have yet to make a significant presence in India. With the temperatures being on the warmer side in most of the consuming parts of India, the study does not augur well for their increased usage as a packaging material in the coming years. |