Even the high-quality wine like Pinot Noir can have different taste and colours depending on where it was produced, says a study.
Winemakers the world over that produce Pinot Noir start with the same thing -- grapes -- and end up with very different products.
"We wanted to find out what causes those differences," said Heli Siren and her colleagues from University of Helsinki, Finland.
In the study, the team analysed the chemical profiles of eight Pinot Noir wines from different regions -- the US, France, New Zealand and Chile.
They found that each wine had a different profile, affected by the processes used to make it. Winemakers add sucrose and other chemicals during manufacturing.
By looking at the acids -- the organic compounds -- in the wine, the researchers could determine which sugars had been added during processing.
They could also find out whether sulphur dioxide was added to prevent the wine from oxidising.
The processes used were different for each wine and included natural fermentation, biodynamic fermentation (using organically-grown grapes), micro-oxygenation and cold fermentation.
The results showed that the wines with the lowest organic compound levels were made using the newer processes: biodynamic and micro-oxygenation fermentation.
"When I pick up a bottle of wine, I would like to drink, I first like to read what it contains. The alcohol content is already on the label, but it might also be helpful if there was information on the sugar, organic acid and mineral content," Siren explained.
Wine bottles should carry information about what the manufacturers add during processing -- including sugars and acids, the team concluded.
The research was published in the journal Analytical Chemistry Research.