What is E948?

Oxygen.

http://www.food-info.net/uk/e/e948.htm

Here is a fairly extensive listing of "E numbers."


http://en.wiktionary.org/wiki/Category:E_numbers

Why is oxygen called E948?

Abbreviation
E948
1. (E number) oxygen when used as a packaging gas

http://en.wiktionary.org/wiki/E948

Packaging gases in food are inert gases employed to occupy space in packaging. If ordinary air is used, this may encourage microbial growth or oxidation of the food.

https://industry.airliquide.us/food

Brainyblonde, Oxygen is not an inert gas.

Well, that's a Royal Society of Chemistry site she's quoting.... i couldn't see why anyone would use oxygen for packaging until I looked at http://www.food-info.net/uk/e/e948.htm If you use it for vegetables, it will stop the vegetable trying to grow, as carbon dioxide is needed for that. (Plants take in carbon dioxide in the day, and put out oxygen at night.) Oxygen should give no reaction with plant material (unless the plant material is heated to quite an extent, that is). I would have thought nitrogen would be just as good for this job, though.