Mono and di-glycerides are fatty substances that are used as emulsifiers. Emulsifiers are compounds used to keep oils or fats and water dispersed in one phase (i.e., they prevent oil and water from separating).
Mono and di-glycerides can be derived from animal or vegetable sources. When derived from vegetable sources, they are halal. When derived from animal sources, they are questionable. More information is required to determine if they are halal.
Halal consumers should avoid products containing mono- and diglycerides unless they are labeled as 100% vegetable mono- and diglycerides. Mono- and diglycerides are used in a wide variety of products, including baked goods, peanut butter, margarine, shortening, and other products.
And ALLAH, Subhanahu wa ta’ala, knows best.