Quite a remarkable history for a company I had never heard of! The aerated bread process, invented by its founder John Dauglish, involved forcing pressurised carbon dioxide into dough, and was the primary way of making industrially produces bread for nearly a century until the Chorleywood process replaced it in the 60s. Later, the firm had a chain of tearooms that were so omnipresent that George Orwell, Bram Stoker and Agatha Christie referenced them in their writing.
This article -- esp. the "In literature" section -- is one of those Wikipedia hidden gems which leave you amused but also worried for them being one day thoughtlessly pruned by some Paladin of Significance