Mono- and diglycerides of fatty acids (E471) refers to a food additive composed of diglycerides and monoglycerides which is used as an emulsifier. This mixture is also sometimes referred to as partial glycerides.
Monoglycerides and diglycerides are both naturally present in various seed oils, however their concentration is usually low and industrial production is primarily achieved by a glycerolysis reaction between triglycerides (fats/oils) and glycerol. The raw materials of this may be either vegetable or animal fats and oils.
E471 is mainly produced from vegetable oils, although animal fats are sometimes used and cannot be completely excluded as being present in the product. The fatty acids from each source are chemically identical.The Vegan Society, which discourages eating animal-based foods, flags E471 as a "thing to look out for" that "can be animal OR non-animal based".