While performing the HPLC separation of hydroxymethyfurfural (HMF) from in-bottle sterilised milk samples, two unknown compounds, named by us as X and Y, were observed.
Preliminary data indicated that the amount of compound X in the samples was dependent on the intensity of the heat treatment applied to milk.
Compound X was isolated from heated solutions of lactose/caseinate and milk, and puri®ed by semi-preparative rp-HPLC.
Applying HPLC-DAD, UV, IR, GC±MS and NMR analysis it was possible to identify it as galactosylisomaltol.
The analysis of HMF and galactosylisomaltol enables to follow simultaneously, the
Amadori product degradation through 1,2- or 2,3-enolisation in milk systems.
Higher levels of galactosylisomaltol were found in in-bottle sterilised samples as compared with UHT-treated and pasteurised milks.
Galactosylisomaltol was not found either in raw or pasteurised milk.
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