Nobody has ever really known what the AB stood for. 'Anal blockage' was the most common answer but in reality it was : 'ArseBursters' based on their well known ability to glue your outlet valve so tight, you thought you were about to get a turtle's head a la Alien. These really were the food of Satan: thousands of soldiers spent millions of man hours trying to make them taste OK, and in the end, all they were able to do was crumble them into a compo all-in stew, alongside the Beef and Onion and Macedoine (and with the Apple and Apricot Flakes if the hideous truth be told). Thank God for Biscuits Brown and the even more exotically named Biscuits BGMB.
Is also a witch.
Flash Traffic - meaning of AB found! Apparently it stands for "Alternative Bread", which makes a certain sort of sense...... can't exactly slap a few slices of Sunblest into a bag, put it on a shelf in the QM's store, issue it exactly two weeks before the ration pack goes past its shelf life, and expect to have the fluffly white makings of a nice sandwich.
Of course, the Americans have just spent millions developing MRE sandwiches which apparently allow you to do just that....