Studies on relationship between sensory evaluation and chemical composition in various breeds of pork

Loins of Berkshire (B), Landrace (L), Large White (W), Duroc (D) and 3 way cross breed (LWD) of finishing guts were used to examine the relationships between sensory evaluation and the chemical composition of taste component. Tenderness, flavor, taste and total score were judged for sensory evaluation by a panel consisting of untrained members of 170. Major nutrients, free amino acids and nucleic acid (inosine monophosphate IMP) contents,fatty acids composition in loin, and the melting point of back fat were measured. Fat content varied between 1.51% (pork W) and 5.11% (pork D). Total content of free amino acids was highest at pork B and lowest at pork L. Glutamic acid content was ranked from highest to lowest in the following order: pork B, W, D, LWD, and pork L. Umami (glutamic acid+asparatic acid) and sweet (serine+glycine+threonine) taste were highest at pork B. In IMP content, pork LWD was highest, pork D and W were medium, and pork B and L were lowest. Palmitoleic acid content was highest at pork B, and lowest at pork W. Stearic acid content was highest at pork W, and lowest at pork B. The melting point was highest at pork W and lowest pork B. In the sensory evaluation, tenderness score was ranked according to order of highest to lowest: pork B, L, LWD, D, and pork W. About flavor, pork B got the highest evaluation, but there was not so much difference among the breeds. Taste score was ranked from highest to lowest with order of pork B, LWD, L, D, and pork W. Total score ranked from highest to lowest with order of B, L, LWD, D, and W. Pork B, which showed the highest content of free amino acids, and the highest tenderness and flavor, was judged to be most tasty by the panel. By contrast, pork W was judged to be least tasty, although it was on the 2nd highest levels in amino acids and inosine monophosphate contents. This was caused by lower fat content,lowest tenderness, and higher melting point of this meat. Highly positive correlation coefficient between palmitoleic acid content and taste (r = 0.963, P < 0.01), and highly negative correlation coefficient between stearic acidcontent and taste (r=0.951, P < 0.05) were observed. It seems that numerous factors have effects on total taste of pork.