Glucono delta-lactone (abbreviation GDL) or gluconolactone, an inner ester of gluconic acid, is a naturally occurring ingredient commonly used as a coagulant in tofu making, a leavening acid in bakery, a mild acidulant in cheese and meat products, and a sequestrant in some food applications. The European food additive number for it is E575. It is kosher, halal, vegan and GMO free.
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