What it is
E322 covers a family of emulsifying lecithins. Today over 95% of commercial lecithin is extracted from soybeans (often "soy lecithin"), with a smaller share from sunflower seeds. Historically — and still in some artisanal products — lecithin was extracted from egg yolks.
Why it matters
One of the most common emulsifiers in food: chocolate, margarine, salad dressings, baked goods, infant formula, ice cream. Also widespread in cosmetics and pharmaceuticals.
What to do
In modern mass-market food, E322 is almost always vegan (soy or sunflower). If the label specifies "lecithin" without a source, soy is the default. Email the manufacturer if a niche or premium product doesn't clarify — egg-derived lecithin still exists in some traditional bakery and confectionery.