Quality of pig adipose tissue: relationship between solid fat content and lipid composition

The dependence of solid fat content at 20°C of adipose tissues on their fatty acid and triacylglycerol compositions was studied on lipids extracted from tissues from 166 pigs. The solid fat content (SFC20) was 20% on average but varied widely (9-35%). The SFC20 variability was closely related to the proportions of disaturated triacylglycerols and more specifically to palmitoyl-stearoyl-oleoyl-glycerol (R(2)=0.92). The SFC20 variability was also related to the proportions of the saturated fatty acids, palmitic and stearic acids (R(2)=0.94). The part of the variance of SFC20 explained by the proportion of polyunsaturated fatty acids was lower (R(2)=0.48). The iodine value showed a high correlation with SFC20 (R(2)=0.81) but carcass lean content was a poor indicator of the solid fat content of adipose tissues (R(2)=0.06).