Maybe this is why Europeans don’t like Hershey Chocolate.
“Hershey process” milk chocolate is popular in North America. It was invented by Milton S. Hershey, founder of The Hershey Company, and can be produced more cheaply than other processes since it is less sensitive to the freshness of the milk. The process is a trade secret, but experts speculate that the milk is partially lipolyzed, producing butyric acid, which stabilizes the milk from further fermentation. This compound gives the product a particular sour, “tangy” taste, to which the American public has become accustomed, to the point that other manufacturers now simply add butyric acid to their milk chocolates.”
“Butyric acid is found in butter, Parmesan cheese, and vomit, and as a product of anaerobic fermentation (including in the colon and as body odor).”