• Asian-Australasian Journal of Animal Sciences
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• v.28 no.3
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• pp.442-450
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• 2015

Climate temperature affects animal production. This study was conducted to evaluate whether climatic conditions affect beef carcass characteristics of Korean cattle steers. The monthly carcass characteristics of Korean cattle steers (n = 2,182,415) for 8 yr (2006 through 2013) were collected from the Korean Institute for Animal Products Quality Evaluation. Daily climate temperature (CT) and relative humidity (RH) data were collected from the Korean Meteorological Administration. Weather conditions in South Korea during summer were hot and humid, with a maximum temperature of $28.4^{\circ}C$ and a maximum RH of 91.4%. The temperature-humidity index (THI), calculated based on CT and RH, ranges from 73 to 80 during summer. Winter in South Korea was cold, with a minimum temperature of $-4.0^{\circ}C$ and a wind-chill temperature of $-6.2^{\circ}C$. Both marbling score (MS) and quality grade (QG) of Korean cattle steer carcasses were generally best (p<0.05) in autumn and worst in spring. A correlation analysis showed that MS and QG frequencies were not associated (p>0.05) with CT. Yield grade (YG) of Korean cattle steer carcasses was lowest (p<0.05) in winter (November to January) and highest in spring and summer (May to September). A correlation analysis revealed that YG frequency was strongly correlated ($r{\geq}0.71$; p<0.01) with CT and THI values. The rib eye area, a positive YG parameter, was not associated with CT. Backfat thickness (BT), a negative YG factor, was highest in winter (November and December). The BT was strongly negatively correlated ($r{\leq}-0.74$; p<0.01) with CTs. Therefore, the poor YG during winter is likely due in part to the high BT. In conclusion, YG in Korean cattle steer carcasses was worst in winter. QGs were not associated with winter or summer climatic conditions.

• Korean Journal of Veterinary Service
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• v.28 no.3
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• pp.215-223
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• 2005

The bacteria on the surface of slaughtered meat was monitored to investigate the relationships between microbiological quality and sanitation management in slaughter process of cattle and pig. It was conducted to evaluate the microbiological quality on the surface of slaughtered beef and pork in Seoul from January to December 2004. Two hundred and thirty three beef and 233 pork carcasses were surveyed on generic E coli counts and standard plate count for microbiological quality and Salmonella spp, Listeria monocytogenes, Staphylococcus aureus, Clostridium perfringens and E coli O157: H7 as pathogenic microorganisms. The prevalence of the excellent or good grade $(10^4\;CFU/cm^2)$ in beef and pork carcasses were $100\%\; and\;99.2\%$, respectively. The frequency of beef carcasses with less than $10^2\;CFU/cm^2$ of generic I coli counts was $100\%$, while that of pork carcasses was $99.6\%$. Of 233 beef carcasses, $1(0.42\%)$ was contaminated with L monocytogenes and $6(2.58\%)$ with C perfringens. Of 233 pork carcasses, $11(4.72\%),\;2(0.86\%),\;and\;2(0.86\%)$ were contaminated with L monocytogenes, C perfringens, and S aureus, respectively, Salmonella spp and E coli O157:H7 were not detected with all of the beef and pork carcasses. In conclusion, this study emphasized the Importance of relationship between microbiological quality and sanitation management in slaughter process of cattle and pig, in abattoirs.

• Food Science of Animal Resources
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• v.39 no.4
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• pp.655-667
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• 2019

The present study aimed at investigating the effects of dry- and wet-aging methods on flavor compounds and sensory properties of low fat Hanwoo beef muscles. All the beef samples were obtained from 2-grade carcasses of Hanwoo cows. The beef samples used in the dry- and wet-aging methods were prepared in the forms of quarter beef (bone-in) and cuts (boneless), respectively. The dry-aging was carried out at $2^{\circ}C-4^{\circ}C$ and humidity of 65%-85%, while the wet-aging was done at $1^{\circ}C$ for 0, 20, 40, and 60 d. At each aging time, three muscles: longissmus thoracis (LT), glutaeusmedus (GM) and semimembranosus (SM) were taken from the corresponding quarters and cuts, and used for the flavor compounds and sensory analyses. Results showed that both aging methods significantly increased the concentrations of flavor compounds and total amount of all classes of the flavor compounds as the aging time increased (p<0.05). In the dry-aging method, the GM and SM muscles presented significantly higher total amounts of pyrazines and sulfur-containing compounds compared to the LT muscle (p<0.05). Both the aging methods improved the eating quality attributes, indicating by increased scores of sensorial attributes with increased aging time for all the muscles studied (p<0.05). However, compared to the wet-aging, the dry-aging method resulted in significantly higher scores of tenderness and flavor for the GM and SM muscles after 40 to 60 d. Thus, postmortem aging, especially the dry-aging method could be used to improve eating quality attributes (tenderness and flavor) of low fat beef muscles such as GM and SM.

• Food Science of Animal Resources
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• v.21 no.1
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• pp.80-88
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• 2001

This study was carried out to evaluate the different physicochemical properties of various lipid sources in beef patties during storage for 6 months. Four groups of samples were made of beef meat patties with 22% of tallow, lard, chicken fat and 20% of palm oil. On the analysis result of physicochemical compositions, the patty has its own fatty acids composition and characteristic different from other lipids. Patty with chicken fat has the highest percentage of unsaturated fatty acid composition of 61.0% compared to the other groups of patties. Beef patty with chicken fat has 18.8% of poly unsaturated fatty acid(USFA) and beef patty with beef lipid has 1.5% of poly USFA which is the least percentage among the others. SFA/USFA ratio of beef patty with chicken lipid was 0.5 which was the least value. The composition of PUFA in beef patty with lard increased to 10.0% from 1.9% over initial value after storage for 6 months. On the contrary, the composition of PUFA in beef patty with chicken fat decreased to 9.2% from 18.8% over initial value after 6 months. Volatile free fatty acids of beef patties were evaluated with four kinds of lipid sources. Formic acid was the most as of 59$\mu\textrm{g}$/g in beef patty with tallow, acetic acid was 15$\mu\textrm{g}$/g, and heptanoic acid was 10$\mu\textrm{g}$/g at starting time of storage. However, propionic acid, butyric acid, valeric acid and caproic acid were not detected. After 6 months, formic acid decreased from 59$\mu\textrm{g}$/g to 7$\mu\textrm{g}$/g in the patty with tallow, from 12$\mu\textrm{g}$/g to non-detect level in the patty with palm oil, but two the others patties slightly increased. Volatile compounds in meat patties were reported nearly 1000 kinds of chemical compounds. Beef patty with tallow has aldehydes 5.3, alcohol 1.3, hydrocarbon 0.8, ketones 0.2, ester 0.1, furans 0.1, acid 0.04, sulfur 0.03 in peak area at starting and increased to aldehydes 8.5, alcohol 2.1, ketones 0.5, ester 1.0, furans 1.5 in peak area during the storage. But only furans was not detected after 6 months of storage. From starting to 6 months, aldehydes increased 2∼10 times, alcohol increased 2∼3 times, acids 4∼50 times and ester 9∼20 times in beef patties with pork lipid, chicken lipid and palm oil. Some volatile compounds such as alcohol, aldehydes and acids in all kinds of patties significantly increased after 6 months of storage. These increases cause oxidative rancidity taste in meat patties. These results showed that selt-life of meat patties with 4 different lipids were not over 6 months even though they were stored at -20$^{circ}C$. Therefore, they should be classified as off-grade because of oxidative rancidity. Although beef patties with tallow are currently common type, the possibility for new type of hamburg patty can be developed by applying different lipids. Finally, we found out new type of beef patty added with lard, which has the best taste and quality compared to the other common types.

• Food Science of Animal Resources
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• v.29 no.6
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• pp.726-735
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• 2009

This study was conducted to investigate the Warner-Bratzler shear force (WBS), sarcomere length, total collagen contents and consumer tests of different cuts of Hanwoo beef based on quality grade. Five cuts [Cheggt (striploin), Dngsim (loin), Moksim (chuck roll), Udoon (top round), Yanggi (brisket)] were obtained from Hanwoo beef (bulls and steers, 24-30 months old) and grouped by their quality grades ($1^{++}$, $1^+$, 1, 2 and 3). The WBS values of chuck cut in $1^{++}$, $1^+$ and 1 quality grade groups were 5.47 (kg/0.5 $inch^2$), 5.46 (kg/0.5 $inch^2$) and 6.54 (kg/0.5 $inch^2$), respectively, which were significantly lower than those of chuck in quality grade 3, which was 8.41 (kg/0.5 $inch^2$) (p<0.05). The sarcomere length of the quality grade groups were significantly longer for brisket (3.72 ${\mu}m$) of $1^{++}$ quality grade than for that of 3 quality grade brisket (p<0.05). Brisket of $1^{++}$ and 2 quality grade had significantly greater sarcomere lengths than strip loin and top round in the same quality grade (p<0.05). The total collagen contents of strip loins in the $1^{++}$, $1^+$, and 1 quality grade groups (1.17, 1.18 and 1.14 g/100 g, respectively) were significantly lower than those of the 3 quality grade group (1.63 g/100 g) (p<0.05). The overall sensory scores of tenderness and juiciness for the five cuts of $1^{++}$ quality grade were significantly higher than those of the other quality grade (p<0.05). Among the five cuts, loin had the highest tenderness and juiciness scores (p<0.05), whereas top round had the lowest tenderness and juiciness scores (p<0.05). Overall, there were significant differences in the WBS and sensory properties among quality grades and cuts (p<0.05). However, the sarcomere length and total collagen contents of chuck roll, top round and loin did not differ among quality grades.

• Food Science of Animal Resources
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• v.40 no.4
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• pp.497-511
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• 2020

This study aimed at comparing the storage stability, fatty acids profile, volatile flavor compounds and eating quality of Hanwoo beef longissimus thoracis (LT) muscles between two marbling morphological groups (fineness and coarseness). The 1⁺ grade Hanwoo LT muscles were measured for marbling fleck morphology at the 13^th thoracic vertebrae location by using computerized image analysis. Results reveal that both marbling groups had similar proximate composition (protein, fat, moisture and collagen), color and technological quality traits (p>0.05). However, the coarse marbling group presented greater C18:2n6 and polyunsaturated fatty acids contents compared to the fine marbling group (p<0.05). Furthermore, the fine marbling group presented lower volatile basic nitrogen (VBN) and 2-thiobarbituric acid reactive substance (TBARS) contents compared to the coarse marbling group after 14 d storage (p<0.05). Also, higher amounts of C18:2n6 oxidation-derived volatile compounds such as hexanal and 3-ethyl-2-methyl-1,3-hexadiene, were found in the coarse marbling group. In term of sensory aspects, the finely-marbled group received higher scores of flavor and taste compared to the coarse marbling group (p<0.05). Overall, the marbling flecks morphology partially showed its effects on the storage stability, fatty acids profile and eating quality of the 1⁺ grade Hanwoo beef LT muscle.

• The Journal of the Convergence on Culture Technology
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• v.8 no.2
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• pp.385-391
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• 2022

Quality evaluation of beef carcasses is an important issue in the livestock industry. Recently, through the AI monitor system based on artificial intelligence, the quality manager can receive help in making accurate decisions based on the analysis of beef carcass images or result information. This artificial intelligence dataset is an important factor in judging performance. Existing datasets may have different surface orientation or resolution. In this paper, we proposed a two-stage classification model that can efficiently manage the grades of beef carcass image using deep learning. And to overcome the problem of the various conditions of the image, a new dataset of 1,300 images was constructed. The recognition rate of deep network for 5-grade classification using the new dataset was 72.5%. Two-stage evaluation is a method to increase reliability by taking advantage of the large difference between grades 1++, 1+, and grades 1 and 2 and 3. With two experiments using the proposed two stage model, the recognition rates of 73.7% and 77.2% were obtained. As this, The proposed method will be an efficient method if we have a dataset with 100% recognition rate in the first stage.

• Asian-Australasian Journal of Animal Sciences
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• v.6 no.2
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• pp.219-223
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• 1993

A total of 333 calves were evaluated for carcass quality traits including: dressing percentage (DP), yield grade (YG), marbling score (MS), fat thickness (FT) and percent body fat (PF). Mating types included straightbred Angus (A) and Santa Gertrudis (S), the reciprocal crosses of these two breeds and Gelbvieh (G) ${\times}$ Angus. The year of birth, slaughter group and dam breed were found to have greatly influenced DP. Mating types had no effect on DP. For YG, sire breed, sire within sire breed and slaughter group were important. Crossbreds of A ${\times}$ S had the highest YG followed by A purebreds. Crossbreds of G ${\times}$ A had the lowest YG. Sire breed, dam breed and the slaughter group has significantly affected the MS. Sire breed, sire nested within sire breed and slaughter group were found to have greatly influenced the FT. Sires and dams of A produced the greatest FT while sires of G produced the lowest. Slaughter group 2 (slaughtered at 433 days of age) had a greater FT than group 1 (slaughtered at 393 days of age). For PF, sire breed, sire within sire breed, dam breed and slaughter group had significant effects. A purebreds had the largest PF while S purebreds and G ${\times}$ A crosses had the least.

• Food Science of Animal Resources
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• v.33 no.2
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• pp.287-293
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• 2013

This study was conducted to investigate the effect of quality grade on the physicochemical and sensory properties of Hanwoo beef on the basis of four quality grades (grade $1^{{+}{+}}$, $1^{+}$, 1, and 2). Significantly decreased levels of myoglobin content (from 12.73 mg/g to 7.90 mg/g) and Warner-Bratzler shear force (WBs) (from 28.01 kg to 14.03 kg) were found with reduction in quality grade (p<0.05). In contrast, increasing quality grade correlated with significant increase in crude fat contents (from 8.18% to 19.55%). Crude fat contents showed a negative correlation with moisture content (r=-0.966), myoglobin content (r=-0.998), and WBs (r=-0.969). In sensory evaluation experiments it was revealed that quality grades were associated with significantly altered (all p<0.05) flavor, taste, juiciness, tenderness, and overall acceptability. Moisture contents showed negative correlation with taste (r=-0.969) and overall acceptability (r=-0.988). Crude fat contents showed significant correlation with taste (r=0.971), tenderness (r=0.983) and overall acceptability (r=0.968). WBs showed negative correlation with taste (r=-0.957) and overall acceptability (-0.978). The marbling score of fresh meat showed significant correlation with taste (r=0.958), juiciness (r=0.953), and overall acceptance of cooked meat. These results could be used as a fundamental dataset to evaluate the effect of quality grade on the physicochemical and sensory characteristics of Hanwoo beef.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.2
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• pp.259-266
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• 2005

Steers (n=335) of known genetic backgrounds from four fundamentally different growth types were subjected to two production systems to study differences in carcass traits. Growth types were animals with genetic potential for large mature weight-late maturing, intermediate mature weight-late maturing, intermediate mature weight-early maturing and small mature weight-early maturing. Each year, in a nine-year study, calves of each growth type were weaned and five steers of each growth type were developed on pasture or feedlot and slaughtered at approximately 20 and 14 months of age, respectively. Data collected were pre-slaughter shrunk body weight (SBW); hot carcass weight (HCW); dressing percentage (DRESS); fat thickness at the $12^{th}$ and $13^{th}$ rib interface (FAT); percentage kidney, pelvic, and heart fat (KPH); longissimus muscle area (LMA); marbling score (MARB); quality grade (QG); and yield grade (YG). Year and growth type were significant for all carcass traits. The growth type${\times}$production system interaction was an important source of variation in SBW, HCW; FAT, YG and MARB. The same interaction was non-significant for DRESS, KPH, LMA and QG. Carcass differences in measures of fatness were greater in the feedlot system than in the pasture system. These data could aid producers in matching beef growth type to the production system most suitable for efficient use of resources.