After criticising it in a newspaper piece as having"no great nutritional value", Dr Briffa found the Quorn company in touch with keen to explain the nutritional and "natural" nature of their product. In a great post on his blog, Dr Briffa reproduces the email exchanges. It is science versus dogma and marketing and very revealing!
Wikipedia has an interesting bit on Quorn referring to some of the controversies associated with this weird product quoting:
complaints with advertising and trading-standards watchdogs in Europe and the USA, claiming that the labelling of Quorn as "mushroom based" was deceptive. The CSPI, observing that while a mushroom is a fungus, fusarium is not a mushroom, and they quipped, "Quorn's fungus is as closely related to mushrooms as humans are to jellyfish."
This is quite interesting in the context of the recent post on nanotechnology in food and the ideas Scott discusses here.