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

Abstract

Gas chromatography (GC) analysis of fatty acid methyl esters (FAME) typically uses long capillary columns (≥ 100 m) 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 quantified using a 30 m compared with 120 m moderately polar capillary (BPX70) column. Lamb and beef samples with a range of intramuscular fat content from either grass- or grain-fed animals were analysed. All major FAME of human health importance, including omega-3 and omega-6 polyunsaturated fatty acids and conjugated linoleic acid (CLA) isomers, could be identified on the 30 m BPX70 column. The correlation (r2) for fatty acid percentage between columns 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 grain-fed animals due to co-eluting of C18:1n–8t.