The harvest of grapes has just started in France's Chablis, famous for its delicate white wines.But it's been a difficult year for the vineyards.Wine production is expected to be historically low this year after frost and mildew fungus ravaged vines.In the Yonne region where Chablis is produced, two thirds of the harvest was destroyed.Producers like Laurent Pinson found a remedy though. He burned large 'candles' - actually cans of paraffin - to protect the vines from sharp spring frosts:"The plots which we protected during the spring frost are quite nice looking so it's promising for the harvest and the quality of the wine."But many of Pinson's fields weren't so lucky.And lower overall production will force him to lift prices:"We can accept a loss of ten or twenty percent in our harvest, we can absorb it over one or two years with a little price increase. But if we have a big loss, like two thirds as we expect, we will have to dramatically increase our prices. But will our customers accept that ? That is the question."Temperatures in April plunged as low as -5°C, or 23°F, in wine regions including Chablis.Chablis produces its fruity white wine from Chardonnay grapes. Over 70% of the output is exported with key markets in Asia, northern Europe and the U.S.But drinkers may find that the wine is about to get a whole lot more expensive.