The food enzyme chymosin (EC 188.8.131.52) is produced with the genetically modified Aspergillus niger strain by Chr. Hansen. The genetic modifications do not give rise to safety concerns. The food enzyme is free from viable cells of the production organism and its DNA. It is intended to be used in milk processing for cheese production and for the production of fermented milk products. Dietary exposure was estimated to be up to 0.09 mg total organic solids (TOS)/kg body weight (bw) per day in European populations. Genotoxicity tests did not raise a safety concern. The systemic toxicity was assessed by means of a repeated dose 90-day oral toxicity study in rats. The Panel identified a no observed adverse effect level at the highest dose of 1,000 mg TOS/kg bw per day the highest dose tested, which when compared with the estimated dietary exposure, results in a margin of exposure of at least 10,600. Similarity of the amino acid sequence of the food enzyme to those of known allergens was searched and two matches with respiratory allergens were found. The Panel considered that, under the intended conditions of use, the risk of allergic sensitisation and elicitation reactions by dietary exposure cannot be excluded, but the likelihood for this to occur is considered low. based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.