Relating texture properties and composition of bovine fat tissue

The relationship of various texture variables and fatty acid composition wa s studied in bovine kidney fat. Fat samples were obtained from 6 x 5 Brown Swiss bulls fed on one out of six diets containing different fats in order to achieve a high variability in depot fat composition. Melting curves, sol id fat content, fatty acid composition, and three mechanical variables (cut ting, extrusion, and adhesion force) were determined to characterize textur e properties. Additionally, four sensory texture attributes (firmness, adhe siveness, friability, spreadability) were evaluated by manual inspection. D iscriminant analyses showed that fatty acid composition as well as melting behaviour together with solid fat content are suitable to classify kidney f at according to the fat used in nutrition. Data obtained by mechanical and sensory texture measurements were less discriminative. All these texture at tributes were closely correlated with each other. Extrusion force showed hi ghest correlations with sensory attributes and therefore was considered to be most suitable to describe kidney fat characteristics beside melting beha viour and solid fat content. According to stepwise regression analyses, ste aric acid, oleic acid, and fatty acids less than or equal to C-16 were impo rtant to explain the texture characteristics of the fats analyzed. Melting behaviour and solid far content could be best described by fatty acid compo sition (R-2=0.73-0.94). However, in sensory and mechanical attributes, fatt y acid composition on average accounted only for 54% of the variation with the closest relationship found for extrusion force (R-2=0.78).