title: Flavor relationships among muscles from the beef chuck and round.
abstract: This research compared off-flavor notes and the relationship of pH and heme-iron content to off-flavor for different beef muscles. After grading, knuckles and shoulder clods were removed from 16 USDA Choice and 14 USDA Select beef carcasses, vacuum-packaged, and aged for 7 d. The rectus femoris (REC), vastus medalis (VAM), vastus lateralis (VAL), teres major (TER), infraspinatus (INF), and triceps brachii-long head (TRI) were separated, cut into steaks, and frozen (-16 degrees C). Sensory analysis was conducted using a trained taste panel, with steaks grilled to an internal temperature of 65 degrees C. Heme-iron concentration and pH were determined. The INF had lower (P < 0.05) off-flavor intensity ratings and less frequent sour flavor than the other muscles, and the VAL had the most intense (P < 0.05) off-flavor ratings and among the greatest frequency of sour, charred, and oxidized flavors. The frequencies of liver-like, bloody, and rancid flavors were not affected by muscle type. Heme-iron concentration did not differ among muscles. Three USDA Select carcasses had intense off-flavor in the muscles. Liver-like flavor was highly negatively correlated with off-flavor intensity for each of the muscles tested. Muscles rated a 5 or below (on an 8-point rating scale, where 1 = extremely intense off-flavor and 8 = no off-flavor) in off-flavor intensity and identified as liver-like by 30% or more of the panelists were grouped together and compared to normal muscles. Those in the liver-flavored group were less frequently identified as charred, probably because the liver-like flavor was so intense. There were no differences between the 2 groups for sour, metallic, bloody, oxidized, or fatty off-flavor notes. Regression equations containing the linear and quadratic functions of heme-iron concentration, muscle pH, and their interaction were established for the frequency of off-flavor notes within each muscle. The REC, TER, VAL, and VAM showed a relationship between pH, heme iron, and off-flavor intensity (P < 0.05). Liver-like flavor was explained partially by pH and heme iron in the REC, VAM, and VAL (R2 = 0.45 to 0.55; P < 0.05). Few other significant relationships were found. Heme iron and pH were unrelated to metallic, oxidized, or rancid flavors for any of the muscles tested. These data suggest that liver-like off-flavors are specific to individual animals, and that pH and heme iron are not strongly related to off-flavor notes.
authors.affiliation: Department of Animal Science, University of Nebraska, Lincoln, Nebraska 68583-0908, USA.
authors.forename: J L
authors.initials: JL
authors.lastname: Meisinger
authors.forename: J M
authors.initials: JM
authors.lastname: James
authors.forename: C R
authors.initials: CR
authors.lastname: Calkins
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D002417:Cattle; D003258:Consumer Behavior; D003296:Cooking / Q000379:methods; D006418:Heme / Q000032:analysis; D006801:Humans; D006863:Hydrogen-Ion Concentration; D016018:Least-Squares Analysis; D008460:Meat / Q000145:classification* / Q000592:standards*; D018482:Muscle, Skeletal / Q000737:chemistry*; D013649:Taste; D014481:United States; D016885:United States Department of Agriculture
chemical_list: D006418:Heme