What it is and where it comes from
E472b is E471 (mono- and diglycerides) joined with lactic acid. Lactic acid is made by fermentation and is halal. The question is the E471 inside it. The fatty acids can come from plant oils such as palm, soy, sunflower or rapeseed, or from animal fat, including pork fat. Most made today is from plants, but the label rarely says which.
Where you find it
Cake mixes, whipped toppings, desserts and coffee whiteners.
What to look for on the label
Look for a halal logo, a vegan label, or a note such as "of vegetable origin" next to the E-number. If the label says nothing, ask the maker: many companies answer by email within days.
This is a guide, not a fatwa. Recipes change, so check the label, look for halal certification, and ask your local imam where scholars differ.