Who knew Old Engine Oil could be so delicious?

Fifty grams of cheese, says Alexander Macdonald as he presents three British dairy beauties, is perfect for the human diet.

As an American who still struggles with the metric system, I close my eyes and try to imagine if I've hit the quota. Very likely, says Macdonald, sparing me the exercise.

"Many Americans eat more than a kilogram of cheese!" he says, spreading his arms as the mostly Chinese audience draws a collective breath of amazement - or downright horror. "That's why they are so ... big."