The analysis of lamb and beef fatty acids with a 30 m BPX70 column is comparable with a 120 m column

Abstract

Abstract Gas chromatography (GC) analysis of fatty acid methyl esters (FAME) typically uses long capillary columns (100 m or greater) which can be expensive and time consuming. The current study determined whether the major FAME of interest for human health in lamb and beef can be quantify using a 30 m compared with 120 m moderately polar capillary (BPX70) column. Lamb and beef samples were selected to cover a range of total intramuscular fat content and from either grass- or grain-fed animals. Results from the current study indicated that all major long-chain FAME of human health importance, including omega-3 polyunsaturated fatty acids (n-3PUFA), omega-6 polyunsaturated fatty acids (n-6PUFA) and conjugated linoleic acid (CLA) isomers, could be identified on the 30 m BPX70 column. The correlation (r2) for fatty acid proportions between columns for both lamb and beef was > 0.98 for all major n-3PUFA and > 0.86 for all major CLAs. When animals were fed a grain-based diet, C18:1n-7t (vaccenic acid) could not be resolved from C18:1n-8t when analysed on the 30 m column. The FAME profile of lamb and beef, particularly those important for nutritional composition tables, can be determined using a 30 m BPX70 column, thereby saving time and expense compared with longer columns. Particular care should be employed when analysing samples from sheep or cattle that are grain-fed due to co-eluting of C18:1n-8t.