Hans Kremmel will never forget his first trip to the city of Guangzhou in 1971 in the middle of the Cultural Revolution. Hearing a knock outside his hotel room one evening, the young Austrian businessman opened the door to find a German-speaking Red Guard ready to preach from Mao Zedong’s Little Red Book.

After enduring the same ritual several times, the 24-year-old ran into a French friend from Hong Kong in the hotel bar, who provided a neat solution. “Just open the door stark naked and they will run away.” The next evening Mr Kremmel followed the advice exactly, which sent the guard packing for good in “total confusion”.

Mr Kremmel is recounting the story over steak and wine in the canteen of a factory he co-owns in Heshan city, 70km from Guangzhou, capital of the manufacturing powerhouse Guangdong province. The bon vivant chairman of KTC, which owns the factory, visits regularly when not in Hong Kong, Austria, or on his farms in the UK and Tuscany.