Undesirable sulphur and carbonyl flavour compounds in UHT milk : a review

Abstract

UHT processing, leads to the formation of “cooked” and “flat” flavours in milk. These undesirable notes occur due to the volatile formation of a variety of sulphur containing compounds, methyl ketones and aliphatic aldehydes derived from the constituents of the milks matrix during thermal processing and storage. The “cooked” flavour of UHT milk is associated with the presence of a variety of sulphur containing compounds while the “stale” flavour is characterised by the dissipation of these sulphur volatiles and an increase of the formation and presence of both methyl ketones and aliphatic aldehydes over time. The extent that the individual volatiles contribute to the overall flavour of UHT milk is not clear. The proposed formation of these volatiles; methods to control the intensity of “cooked” and “stale” flavours associated with UHT milk and extraction techniques for the isolation of these volatiles from milk have been reviewed.