Lagers like Stella Artois are bottom-fermented while classical Belgian beers are top-fermented. Lagers are more transparent and look “cleaner” in a transparent glass. Perhaps because of this, demand shifted to lagers. The share of lager beers in Belgium went from 15% before WW1 to 70% after WWII.
Bottom fermentation requires more equipment to cool the beer during fermentation and maturation. Hence, it gains from greater scale. Greater demand plus cost economies led to the market shifting towards a few large breweries. These set a lower price than smaller breweries and drove them out of business. Add to this the costs of advertising and scale advantages multiply….
For this and and more on Lambics and Abbey beers see Belgian Beers: Where History Meets Globalization
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March 3, 2011 at 2:45 pm
azmyth
That explains why so many craft breweries make ales, since that is their comparative advantage compared to the larger breweries.
March 3, 2011 at 4:22 pm
Sandeep Baliga
Yes. One more fun fact from paper: As abbey beers gained international sales, some big breweries produced “abbey” beer using names of defunct abbeys. Now, there is some stamp of authenticity to stop this practice.