No abstract

The physicochemical and functional traits for loin muscles of Hanwoo steers were compared by quality grade (QG). A total of 500 Hanwoo steers were slaughtered, their carcasses were categorized into four groups (QG 1++, 1+, 1, and 2), and the longissimus dorsi muscles were analyzed. QG 1++ group had the highest fat and lowest moisture content (p<0.05). QG 1++ showed higher L* and b* color values, higher cooking loss, and lower shear force values, compared with the other groups (p<0.05). The flavor, tenderness, juiciness, and preference scores by sensory evaluation were highly ranked for premium QG groups (1++ and 1+). Regarding the micro compounds, QG 1 and QG 2 had greater amounts of inosine monophosphate, and QG 2 had greater amounts of anserine, carnosine, and creatine, than QG 1++ (p<0.05). QG 1++ and 1+ had higher percentages of oleic acid (C18:1) than QG 2 (p<0.05). Within premium QG 1++ and 1+, the results of the nucleotides, free amino acids, dipeptides, and fatty acids did not show any distinctive differences. Hanwoo beef as determined by the current grading system was not significantly different in terms of functional components; the only significant difference was in intramuscular fat content.

To evaluate the meat quality differences of Korean Native Chickens (KNC) available in Korean market, the physicochemical and sensory characteristics of a broiler and two KNC (HH and WD breed) were analyzed. The fat content of KNC WD breast meat was higher than that of KNC HH. The breast and thigh meats of KNC HH had higher L * and a * values than the broiler or the KNC WD. WD meats showed greater DPPH radical scavenging activity and higher pH values than the HH. For the fatty acid composition, there was no significant difference in total content of the saturated fatty acids among chicken breeds (p>0.05). KNC had greater content of polyunsaturated fatty acids, especially arachidonic acid (20:4) and DHA (22:6), compared with the broiler. KNC WD meats had higher composition of linolenic acid (18:3) than the KNC HH. For sensory evaluation, the WD breast meat showed higher taste and tenderness scores than the HH. On the other hand, the soup made by broiler had higher taste scores than the KNC. The breast and thigh meat from two KNC breeds showed different quality parameters that may come from the differences of genetic attributes, feed, and production strategy between two breeds.

The combined effects of electron-beam irradiation and ageing of beef were examined. The irradiated samples at dose of 0 or 2 kGy were kept and analyzed for the microbial growth, shear values, meat color, and nucleotide-related flavor compounds at different ageing temperatures (2, 10, or 25℃) for 8 d. The irradiation effect on inactivation of foodborne pathogens was also investigated. The population of Listeria monocytogenes and E. coli O157:H7 inoculated in beef samples decreased in proportion to the irradiation dose, showing D10 values of 0.66 and 0.65 kGy respectively. The irradiated beef eye of round had lower number of total aerobic bacteria (TAB) than non-irradiated one during the storage, but the TAB increased with higher ageing temperature (p<0.05). Especially, TAB increased sharply in non-irradiated samples aged at 25℃ after 4 d (p<0.05). With increasing ageing temperature and ageing time, shear force values decreased (p<0.05). The color a* values of the irradiated beef were lower than those of the non-irradiated throughout the ageing period (p<0.05). As ageing time and temperature increased, the amounts of inosine monophosphate decreased and the hypoxanthine increased (p<0.05). Relatively high ageing temperature could be used at irradiated beef eye of round to shorten the ageing time.

This study was performed to determine the meat quality characteristics of pork loin and belly from 3 different three-way crossbred pigs: Yorkshire × Landrace × Duroc (YLD), Yorkshire × Chester White × Yorkshire (YCY), and Yorkshire × Berkshire × Duroc (YBD). Each of the twenty crossed pigs were randomly selected with their live weights at the range of 110-120 kg. After being slaughtered and cooled at 0℃ for 24 h in a chilling room, the parts of loin and belly on the left side of the cooled carcasses were cut and prepared for analysis. The intramuscular fat contents of the loins from YLD were higher than those of the other crossbreds (p<0.05), and the YCY bellies had the highest moisture contents (p<0.05). Water holding capacity (WHC) of the loins from YCY were higher than the other crossbreds (p<0.05). Shear force values of the YBD loins were higher than the others (p<0.05). The TBARS values of YCY loins were significantly lower than the others at 0 d, but the difference disappeared after 14 d of storage. Sensory scores of YLD were ranked higher than the YCY or YBD in both the loins and bellies (p<0.05). The relatively high sensory values of YLD crossbred pork could be explained by the better WHC, the low shear forces, and the higher fat contents. The results indicated that the meat qualities could be altered by three-way crossbreeding.