The prediction of fatty acid composition in beef muscles using Raman spectroscopy and chemometrics

Raman spectroscopy was applied in the study to determine fatty acid composition in seven beef muscles; eye round, heel, oyster blade, rump, shin, striploin, tenderloin. The fatty acids were extracted and derivatised and analysed using Gas chromatography flame ionisation detection (GC-FID). Predictions using Partial Least Squares Regression (PLSR) varied from poor R-2 cross validation ((RCV)-C-2) of < 0.50), moderate ((RCV)-C-2=0.50-0.65) to good ((RCV)-C-2=0.67 - 0.90) depending on the fatty acids being studied. Fatty acids with a good predictability were for SFA C14:0 ((RCV)-C-2=0.80), MUFA C18:1 n9 trans ((RCV)-C-2=0.71), PUFA C22:2, ((RCV)-C-2=0.85), omega-3 FA C18:3 n3 ((RCV)-C-2=0.68) and omega-6 FA C20 4 n6 ((RCV)-C-2=0.81). The important regression coefficients were lipid peaks from acyl chains (CH3, CH2), unsaturation modes (CC) and carbonyl groups (CO) for the SFAs detected.