Principal components analysis of the lipid profile of fat deposits in Santa Inês sheep

- The PCA allows the reduction of sample space the fatty acid.
- MUFA + PUFA and SFA were the most significant variables in the fatty deposits.
- The fatty acid C18: 0 was most prominent in the first component.

The aim of this research was to characterise the lipid profile of internal fat deposits in Santa Inês sheep and determine which variables have the greatest explanatory power on the total variation using principal components. Forty two male lambs were used, with a slaughter weight of 28.85 ± 2.33 kg and an average age of 7-8 months. Samples were collected from omentum, mesenteric, kidney and pelvic fat deposits. The fatty acids were separated in a gas chromatograph coupled to a flame ionization detector. The chromatograms, with the data on the retention times and the percentages of areas of fatty acids, were stored in Peak simply type software (ARI Instruments-USA). The first four principal components explained 68.03% of the total variation. Of the total 45 variables, 12 variables were the most relevant in the first 4 components, representing a significant reduction in the sample space, as almost 75% of the variables made small contributions to the total variance. The variables C140, C160, C171n7c, C18:0, C183n6, C203n3c, C204n6c, C23:0, monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), total unsaturated fatty acids (TUFA), saturated fatty acids (SFA), MUFA/SFA, TUFA/SFA, desirable fatty acids (DFA) and atherogenic index (AI) contributed the most to the total variation in the data.