Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10140767 | Food Chemistry | 2019 | 7 Pages |
Abstract
Heating milk fat leads to lactone formation. Hydroxy fatty acids, esterified in triacylglycerol (TAG), are likely precursors of lactones in milk fat, but respective hydroxy TAG isomers have not been directly detected for several decades. In this study, we separated hydroxy TAG isomers-1,2-dipalmitoyl-3-(5-hydroxy decanoyl)-rac-glycerol (PP(C10-5OH)-TAG), 1,2-dipalmitoyl-3-(5-hydroxy dodecanoyl)-rac-glycerol (PP(C12-5OH)-TAG), 1,2-dipalmitoyl-3-(5-hydroxy tetradecanoyl)-rac-glycerol (PP(C14-5OH)-TAG), and 1,2-dipalmitoyl-3-(4-hydroxy dodecanoyl)-rac-glycerol-by using liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) with an octacocyl silylation column. This method revealed the presence of PP(C10-5OH)-TAG, PP(C12-5OH)-TAG, and PP(C14-5OH)-TAG in butter oil, whereas no hydroxy TAG isomers were detected in heat-treated butter oil. Furthermore, a heating test of hydroxy TAG standards showed a decrease in hydroxy TAG levels and an increase in the corresponding lactone levels. These changes were stimulated by adding a small amount of water. This is the first reported analysis of respective hydroxy TAG isomers in milk fat using LC-ESI-MS/MS.
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Kazuaki Yoshinaga, Junji Obi, Arisa Tago, Yasunari Kato, Toshiharu Nagai, Akihiko Yoshida, Naohiro Gotoh,