A stable aqueous liquid lactase formulation is provided, comprising lactase and further comprising sodium, calcium or potassium-L-lactate or a combination thereof and optionally a sugar, and/or optionally comprising sodium or potassium chloride or a combination thereof, preferably wherein the concentration of each of the components is such that the water activity Aw is at most 0.82. The formulation is particularly suitable when using invertase-free lactase, allowing the use of sucrose as stabilizer. Also provided is a process to produce the liquid lactase formulation, an infant formula (e.g. as powder of granulate) comprising the liquid lactase formulation, a method to produce said infant formula, and the use of the formulation in the production of infant formula.
