OK. Here are the article details and abstract....
Adrian C. North, David J. Hargreaves, and Jennifer McKendrick (1999). The influence of in-store music on wine selections. Journal of Applied Psychology, 84, 271-276.
This field study investigated the extent to which stereotypically French and German music could influence supermarket customers' selection of French and German wines. Music with strong national associations should activate related knowledge, and be linked with customers buying wine from the country concerned. Over a two week period, French and German music was played on alternate days from an in-store display of French and German wines. French music led to French wines outselling German ones, whereas German music led to the opposite effect on sales. Responses to a questionnaire suggested that customers were unaware of these effects of music on their product choices. The results are discussed in terms of their theoretical implications for research on music and consumer behaviour, and their ethical implications for the use of in-store music. They put equal numbers of French and German wines of the same sweetness level (8 types of wine in all) on 4 shelves at the end of a supermarket aisle. Here are the numbers of wines sold when each type of music was played:
French music - 40 French bottles - 12 German ones
German music - 8 French bottles - 22 German ones
So the percentge of French bottles bought from that display was 83% in the case of French music, and 35% in the case of German music. The claim that 77% of customers bought French wine when French music was being played is completely wrong, but interestingly enough that happens to be the proportion of the total number of French bottles being sold when French music was being played
Personally I think it is also interesting, and perhaps not surprising, that less wine in total was sold when Bierstube music was being played. I bet it did wonders for beer sales at the supermarket though!
The relatively high proportions of German wine being sold are probably due to it being given equal weight on the display to French wines - the customers were not selecting from the proportions normally being offered today. Note also the research is from 1999, when I think German wine was probably more popular.