The use of a lipid acyltransferase in the manufacture of UHT milk for improving the stability, particularly the long term stability, and/or improving the perceptible sensory difference and/or improving smell and/or taste and/or for reducing the cholesterol content and/or for eliminating or reducing creaming of the UHT milk for reducing the cholesterol content in the UHT milk. A method of producing UHT milk, wherein method comprises admixing a lipid acyltransferase and milk (including a step of processing the milk to make it a UHT milk). Preferably said lipid acyltranferase is a polypeptide having lipid acyltransferase activity which polypeptide is obtained by expression of the nucleotide sequence shown as SEQ ID No. 49 or a nucleotide sequence which as has 70% or more identity therewith; and/or is obtained by expression of a nucleic acid which hybridises under medium stringency conditions to a nucleic probe comprising the nucleotide sequence shown as SEQ ID No. 49; and/or is a polypeptide having lipid acyltranferase activity which polypeptide comprises the amino acid sequence shown as SEQ ID No. 68 or an amino acid sequence which as has 70% or more identity therewith.