If the app user has scanned a barcode we don't recognise, we show a minor feature letting the user create the ingredient. The user can't edit the ingredients afterwards, but the Beefit support team can handle the case.
Since there can be many similar ingredients in some cases, it is a good idea to ask the client for as many details as possible, for example:
Ingredient name (or sent a picture)
Correct macro (or send a picture)
Barcode