What it is
E903 is carnauba wax, extracted from the leaves of the carnauba palm (Copernicia prunifera), native to north-eastern Brazil.
Why it matters
The hardest natural wax — used to coat sweets (M&Ms, jelly beans), polish cars, and as a vegan glazing alternative to E901 / E904. Also widely in cosmetics.
What to do
Always vegan.