본 연구는 한우의 성별에 따른 소분할 부위별 pH, 일반성분 및 육색을 조사하고자 한우 15두(암소 5두, 수소 5두 및 거세우 5두)를 도축한 다음 등급 판정을 한 후 39개 소분할 부위를 발골하여 육질 특성을 분석하였다. 소분할 부위별 pH는 5.52~6.25를 나타내었으며, 대체로 거세우에서 암소와 수소에 비해 높은 값을 나타내었다. 수분, 지방, 단백질 함량은 소분할 부위와 성별에 따른 유의적인 차이를 나타내었다(p<0.05). 수소와 거세우의 앞사태 부위에서 가장 높은 수분함량을 나타내었다(p<0.05). 지방함량은 거세우의 차돌박이 부위에서 가장 높았으며 다음으로 암소의 업진살, 암소, 수소 거세우의 본갈비 순이었다. 콜라겐함량은 암소와 거세우는 부위에 따른 유의적인 차이가 나타나지 않았다(p>0.05). 암소와 거세우의 차돌박이 부위는 높은 명도 값을 나타내었으며, 암소와 수소의 차돌박이 부위는 낮은 적색도 값을 나타내었다(p<0.05). 황색도는 암소, 수소 및 거세우의 차돌박이 부위에서 가장 높은 값을 나타내었다(p<0.05). 색도는 암소, 수소 및 거세우는 홍두깨살 부위에서 가장 높았으며, 암소와 거세우는 업진안살에서 가장 낮은 값을 나타내었다(p<0.05). 2등급 한우고기의 수분함량은 수소가 높고, 지방함량은 암소가 높으며, 거세우는 높은 pH 값과 낮은 명도 값을 나타내었다.

본 연구는 성별에 따른 2등급 한우의 소분할 부위별 보수력, 가열감량, 전단력 및 관능 특성을 조사하고자 실시하였다. 한우 15두(암소 5두, 수소 5두 및 거세우 5두)를 도축한 다음 등급 판정을 한 후 39개 소분할 부위를 발골하여 육질 특성을 조사하였다. 2등급 한우의 소분할 부위별 보수력은 46.97~63.16%를 나타내었으며, 가열감량은 52.44~71.58%로 안심살과 꽃등심살 부위를 제외한 부위에서 유의적인 차이가 나타나지 않았다(p>0.05). 전단력은 2.36~6.80 kg/cm2으로 암소의 안심살, 윗등심살, 꽃등심살, 아래등심살, 부채살, 앞다리살, 갈비덧살, 삼각살, 업진살, 꽃갈비 부위에서 수소와 거세우에 비해 낮은 전단력을 나타내었으며(p<0.05), 거세우의 살치살, 꾸리살, 부채덮개살, 우둔살, 설깃살, 설깃머리살, 도가니살, 양지머리, 차돌박이, 뒷사태, 안창살 부위는 수소와 암소에 비해 낮은 전단력을 나타내었다(p<0.05). 풍미는 윗등심살, 아래등심살, 홍두깨 살, 보섭살, 양지머리 및 차돌박이 부위에서 수소가 암소와 거세우에 비해 낮은 점수를 받았으며, 나머지 부위에서 유의적인 차이가 나타나지 않았다(p>0.05). 저작감은 암소의 아래등심살, 채끝살, 목심살, 꾸리살, 부채살, 설깃머리살 및 차돌박이 부위에서 수소와 거세우에 비해 높은 점수를 받았으며(p<0.05), 거세우의 치마살 및 뭉치사태 부위가 암소와 수소에 비해 높은 점수를 받았다(p<0.05). 종합적인 기호도는 암소의 채끝살, 꾸리살 및 부채살 부위가 수소와 거세우에 비해 높은 점수를 받았으며(p<0.05), 거세우의 윗등심살, 살치살, 앞다리살, 치마살 및 앞치마살 부위가 암소와 수소에 비해 높은 점수를 받았다(p<0.05). 2등급 한우고기는 수소가 암소와 거세우에 비해 높은 보수력을 나타내었으며, 암소와 거세우가 수소보다 낮은 전단력을 나타내었으며, 풍미에서 높은 점수를 받은 거세우의 부위와 저작감에서 높은 점수를 받은 암소의 부위는 종합적인 기호도에서 도 높은 점수를 받았다.

본 연구는 개정된 소 도체 등급판정 세부기준이 개정 목표에 부합되는지를 평가하기 위해 실시되었다. 본 연구에서는 기초 데이터를 바탕으로 데이터의 분포를 도출하고, 도출된 분포를 바탕으로 미래 데이터를 추출하여 이를 분석하는 몬테카를로(Monte Carlo) 방법론을 활용하였다. 축산물품 질평가원의 2019년 1월 2일부터 2019년 5월 31일까지 등급판정을 받은 한우 거세 비육우의 도체정보(n=187,279)를 이용하여 각 도체성적의 분포와 상관관계를 도출하였다. @risk 소프트웨어를 이용하여 10만 개의 가상 도체 데이터를 Latin hypercube 방법으로 추출하여 몬테카를로 시뮬레이션을 실시하고, 각 변수들이 육량지수, 육량등급, 육질등급에 미치는 영향력을 평가하였다. 시뮬레이션 결과, 육량지수는 현행 등급판정 기준과 개정된 기준에서 모두 도체중량이 증가함에 따라 감소하는 것으로 나타났으며 각 변수들에 대한 민감도는 두 기준이 유사하였다. 개정된 기준에서는 도축월령이 증가함에 따라 그 정도는 미미하지만 육량지수 및 육량등급이 저하되는 것으로 나타났다(P < 0.001). 현행 등급판정 기준에서는 그 밖의 도체성적이 동일할 때, 육질등급은 배최장근단면적과 도축월령이 증가할수록 개선되고(P < 0.01), 등지방두께와 도체중량은 육질등급에 유의적인 영향을 미치지 않는 것으로 나타났다. 그러나 개정된 등급판정 기준에서는 육질등급이 모든 도체성적 및 도축월령과 유의적인 관계를 갖는데(P < 0.01), 그 밖의 도체성적이 동일하다면, 도체중량이 클수록, 등지방두께가 얇을수록, 배최장근단면적이 적을수록, 도축월령이 적을수록 육질등급이 개선되는 것으로 나타났다. 결론적으로 새로운 ‘소 도체 등급판정 세부기준’은 도체중량의 증가에 따라 육량등급을 증가시키는 것은 아니나, 현행 기준에 비해 한우의 사육기간을 단축시키는 효과는 클 것으로 기대된다.

This study investigated the effect of temperature deviation on the water-holding capacity, tenderness, lipid oxidation, and color stability of Korean Hanwoo (韓牛) beef during long-term aging. The striploins (M. longissimus lumborum) were aged for 56 days at 2±1oC (T1), 2±2oC (T2), or 2±3oC (T3). Drip loss and cooking loss were higher (p<0.05) in T3 than in T1 on day 56. The Warner-Bratzler shear force value was similar for all treatments during aging times. On day 56, the content of 2-thiobarbituric acid reactive substances was higher (p<0.05) in T3 as compared to T1. The CIE L* and b* values were similar for all treatments, but the a* value was lower (p<0.05) in T3 than in T1 on the last day. These findings indicate that high temperature deviation adversely affects the water-holding capacity, lipid oxidation stability, and color stability of Hanwoo beef during long-term aging.

The objective of this study was to investigate the effects of dry-aging and wet-aging conditions on the chemical composition, meat quality traits (color, water holding capacity, cooking loss, WBSF and pH) and shelf-life TBARS (2-thiobarbituric acid reactive substances) and VBN (volatile basic nitrogen) of loin (M. longissimus thoracis), sirloin (M. glutaeusmedus) and top-round (M. semimembranosus) cuts of Hanwoo cows. The dry-aging condition (temperature ℃, relative humidity %) was done for 60 d as 2℃, 65％, 20 d＋2℃, 75％, 20 d＋4℃, 85％, 20 d while, the wet-aging was done for 60 d at 1℃, 85%. Results revealed that moisture content was significantly higher in the dry-aged samples than that of the wet-aged samples at 60 d (p<0.05). The a*- and b*-values were significantly higher in 3 cuts as compared with those treated with wet-aging condition. During the dry-aging time, the WHC significantly increased in the loin and sirloin and they were significantly higher than wet-aging condition at 40 d and 60 d (p<0.05). The WBSF values significantly decreased with increased aging time and there was no significant difference between two aging methods. The TBARS and VBN contents significantly increased with increased aging time for all the wet- and dry-aged cuts, and their levels still fell within the acceptable standard limit. Generally, the TBARS and VBN contents were significantly higher in the dry-aged cuts, probably due to the increased levels of protein and fatty acids oxidations. Based on the results obtained in the present study, it can be suggested that application of dry-aging method can improve the quality characteristics of beef.

The objective of this study was to investigate changes in drying yield, pH, water activity, microbial growth, and storage stability of bottom rounds of Hanwoo beef under four different dry-aging treatments (T1–T4) as temperature (2~4℃), relative humidity (65~86%) and dry-aging period (20~90 d). The drying yield decreased by 83.13–97.05% as the drying period increased. Among the four treatments, there were no significant differences in drying yield after 60 d of dry-aging. The total plate aerobic counts (TPC) increased by 1.07–4.39 log colony-forming units (CFU)/g as the dry-aging period increased. Of the four treatments, T4 at 40, 60, and 90 d had significantly higher TPCs than those observed for the other treatments on the same days (p<0.05). As the period of dry-aging increased, pH values increased by 5.35– 5.88 for knuckle and 5.34–5.62 for sirloin muscle, and water activity values decreased. For knuckle and sirloin muscle, the water activity values at 40 d and 60 d of T1 and T4 were significantly higher than those of the other treatments on the same days (p<0.05). The thiobarbituric reactive substances and volatile basic nitrogen values of the aged products increased as the dry-aging period increased. The results of this study showed that dry-aging conditions such as those in the T2 or T3 treatments (with a gradual increase in temperature and humidity) for less than 60 d would be best for yield, reduction of microbial growth and storage stability by dry the muscle surface quickly at the beginning period. Further research should include meat quality and economic analysis for these conditions that examines the benefits of these dry-aged products for the end processor.

본 연구는 건조숙성 조건에 따른 한우 설도육의 이화학적 및 관능적 특성 변화를 조사하고자 수행하였다. 한우 거세 1등급 설도육 54개를 구입하여 온도(2℃, 4℃), 상대습도(65%, 75%, 85%) 및 건조숙성기간(10~90일)에 따라 4종(T1~T4)의 조건으로 나누어 건조숙성하면서 도가니살 및 보섭살의 육질특성과 삼각살을 포함한 관능특성을 비교하였다. 도가니 및 보섭살의 지방함량은 4개 처리구 모두에서 숙성기간이 증가함에 따라 유의적으로 증가하였다(p<0.05). 반면에 수분함량은 건조숙성기간이 증가함에 따라 도가니육은 T2와 T4, 보섭육은 T2에서 유의적으로 감소하였다(p<0.05). 도가니 및 보섭육의 육색은 건조숙성기간이 증가됨에 따라 4개의 처리구 모두 L값(백색도), a값(적색도), b값(황색도)이 유의적으로 감소하였다. 가열감량은 도가니육의 경우 T2만 건조숙성기간이 증가할수록 감소되는 경향이었고 나머지 3개 처리구는 유의적인 차이가 없었다. 보섭육의 경우 가열감량은 처리구 4개 모두 건조숙성기간이 증가할수록 감소되는 경향이었다. 동일한 숙성일 내 처리구간 비교에서는 T2가 가열감량이 유의적으로 가장 낮았다. 전단력은 도가니육과 보섭육 모두 4개 처리구에서 건조숙성기간이 증가할수록 유의적으로 감소한 반면(p<0.05) 보수력은 유의적으로 증가하였다(p<0.05). 관능특성 변화에서 도가니육, 보섭육 및 삼각살은 건조숙성기간이 증가할수록 모든 처리구에서 연도가 증가하였다. 다즙성은 도가니육과 삼각살은 T2와 T4에서 증가하였고, 향미는 삼각살만 T2와 T4에서 증가하였다. 본 연구에서 제시된 4개의 처리구에 대한 한우 설도육의 육질 및 관능특성 분석결과 전단력, 보수력 및 연도가 모두 향상되었으며 특히 처리구 2 조건은 가열감량과 관능적 기호도에서 더 유리하게 작용한 것으로 나타났다. 따라서 한우 설도육은 온도와 습도를 단계적으로 상승시키면서 약 60일 이내로 하는 것이 육질, 맛과 경제성 면에서 적절할 것으로 생각된다.

The KLF(Kruppel-like factors) are transcriptional regulators that including the C2H2 zinc-finger motif and regulation of cell growth, cell differentiation, and development. In this study, mRNA and total DNA was extracted from the meat around the backbone of 130 cattle that has economic traits score. The KLF11 gene was act on the center of the main pathway in associated with the development and growth of cells and the fat metabolism. Genetic polymorphism was detected by DNA sequencing. A total of four SNPs(G9047A, C9104G, G9131A, C9170T) were identified in exon 4 regions, statistical association analysis revealed that the G9131A polymorphism were significantly associated with marbling score. The real time quantitative PCR to investigated gene and miRNA expression patterns and identify the relation of economic trait in Korean Native Beef Cattle. Gene expression level linked to KLF11 genes was investigated by determining its association and variation with the economic traits in Korean Native Beef Cattle. The increment of KLF11 gene expresstion level is resulted in increasing marbling score(MS). We found that expression profile of KLF gene and mir-494 was contrast tendency because the lower expression ratio of gene was the higher marbling score rating was when we analyzed expression profile ofKLF gene and mir-494. Therefore, this result has useful in improvement of livestock in Korean cattle.

In this study, the texture, nucleotide-related compounds, and sensory characteristics of dry-aged beef, made from third quality grade Hanwoo beef (Korean native cattle), were investigated according to aging periods. Loin cuts obtained from three different Hanwoos were dry-aged under the specific conditions (controlled temperatures, humidity, and air flow) during 0-7 weeks. With increasing aging periods, textures were significantly decreased after 5 weeks (hardness: from 13,264±2,033 to 7,112±1,743 g; chewiness: from 4,107±1,467 to 2,334±780) and four sensory characteristics were significantly increased after 3 weeks (texture: from 2.2±1.0 to 6.2±1.1; flavor: from 3.9±0.7 to 6.2±1.5; whole preference: from 2.5±0.8 to 6.3±1.3; purchase intention: from 3.7±1.4 to 6.0±1.5) except for color (p<0.05). On the other hand, the concentrations of IMP which is related to the umami flavor of beef were significantly decreased with increasing aging periods (from 40.44±5.97 at 0-week to 7.44±2.43 μg/ mg at 7-week) (p<0.05). These results obtained in this study could provide an useful data base for the quality control of dry-aging.

본 연구에서는 한우 보증씨수소 KPN 493, 586, 614, 632, 666을 암소에게 인공 수정하여 생산된 자손 축 총 60두(5처리×12두씩/처리구당)에 대한 육질의 이화학적 특성과 상관관계를 분석하였다. 등심 면적 및 근내지방도는 KPN 586 자손축이 가장 우수하였으며(p<0.05), 육질의 이화학적 특성에서는 처리구 간에 거의 차이가 없었으나 특히 풍미와 육색의 황색도(b값)가 KPN 493이 가장 좋았다(p<0.05). 지방산중 올레인산은 KPN 493은 가장 높았다(p<0.05). 또한 각 형질별 상관관계에서, 도체중과 등심 단면적, 등심 단면적과 근내지방도에서 정(+)의 상관관계를 나타내었고(P<0.01), 보수력은 수분과 조단백질 함량에서 부(-)의 상관관계를 나타내었 (P<0.01). 또한 연도는 다즙성과 정(+)의 상관관계, 풍미는 다즙성, 연도 간에 정(+)의 상관관계, C18:1n9과 C20:1n9와 불포화 지방산 간에는 정(+)의 상관 관계를 나타내었다(P<0.01).

본 연구의 목적은 한우사료 내 아마씨앗의 급여가 등심 내 오메가 6와 3 지방산 비율(n-6/n-3) 감소효과 및 n-6/n-3 균형 한우고기를 섭취한 사람의 혈액 중 LDL-C 감소효과를 조사하는 것이었다. 단계별로 거세한우 20마리를 이용하여 대조군과 아마씨앗을 함유하는 n-3 처리구로 각각 10마리씩 나누어 완전임의 배치하였다. n-3 사료군은 대조군과 비교할 때 혈액 및 등심 내 n-6/n-3가 4:1이하로 감소하였으며 단일불포화지방산으로써 올레인산은 52.79%까지 증가하였다. 임상실험자의 70% 이상에서 나타난 균형 한우고기를 섭취한 그룹의 중성지방, 총콜레스테롤 및 LDL-C은 각각 25.35, 5.22, 17.59% 감소하였고 수입 쇠고기는 9.05, 8.21, 21.70% 증가하였으나 일반한우는 큰 차이가 나타나지 않았다. 균형 한우고기를 섭취한 그룹의 HDL-C는 6.07% 증가하였으나 수입 쇠고기와 일반한우는 각각 14.46, 11.46% 감소하였다. 혈당은 균형 한우고기와 일반 한우고기가 각각 6.42, 11.82% 감소하였으나 수입 쇠고기는 15.19% 증가하였다.

The aim of this study was to compare the effects of different thawing methods including; refrigerated at 4℃ for 6 hr, soaked in 15℃ water for 40 min, exposed to room temperature (25℃) for 4 hr, and microwaved (600 W) for 2 min on the water-soluble nutritional component and meat quality trait of Hanwoo beef. The thawing beef by the refrigerated method resulted in significantly lower cooking loss, drip loss and loss of water-soluble vitamin B group, whereas the water-soaked method had higher loss of vitamin B group (p<0.05). Furthermore, total aerobic counts and coliforms were significantly lower in the meat samples thawed by the refrigerated method than that in the samples thawed by the other methods when stored for 6 days at 4℃. However, the thiobarbituric acid reactive substance (TBARS) content was found significantly (p<0.05) higher in the microwaved method than that in the other thawing methods. Based on the results obtained in the present study, it is concluded that the thawing methods had remarkable impact on the water-soluble nutritional components, quality properties and storage stability of meat. Therefore, the present study recommends that the thawed meat needs to be consumed and should not be stored for long time due to the acceleration of its quality deterioration

This research was conducted to estimate the effect of packaging methods on the color and taste-related precursors in Hanwoo (Korean cattle) beef during aging. Following packaging with vacuum (VACP), low oxygen-modified atmosphere (LOMAP; 0% O2/20% CO2/80% N2) or vacuum skin+LOMAP (VSP+LOMAP), the loins and top rounds were aged at 2℃ for 14 days and lipid oxidation (TBARS content), surface color, glucose and lactate contents were measured. TBARS and glucose contents were not different by packaging methods in both loins and top rounds. The a* (redness), b* (yellowness) and C* (chroma) values were higher (p<0.05) in VACP-aged beef as compared to the other beef. Lactate content was significantly higher (p<0.05) in both LOMAP- and VSP+LOMAP-aged beef than in VACP-aged beef at day 14 of aging. These findings suggested that VACP was the most effective in maintaining color stability but LOMAP was more effective in maintenance of some taste-related precursor compared to VACP.

The objective of this study was to investigate meat quality and nutritional composition of 10 cuts (loin, striploin, chuck roll, chuck tender, short plate, brisket, bottom round, top sirloin, eye of round, and top round) from quality grade 1 beef from 11 Hanwoo steers at Hanwoo Experimental Station of National Institute of Animal Science. The protein contents were higher in top round (Udoon) and eye of round (Hongduke) and lower in loin (Dngsim) and short plate (Abjin) when compared to the other cuts (p<0.05). Whereas the intramuscular fat contents were highest in loin (12.51%), those were lowest in top round (4.14%) (p<0.05). The calories were higher in loin and short plate and lower in top round, chuck tender (Guri), top sirloin (Bosup), eye of round, chuck roll (Moksim), and bottom round (Sulgit) (p<0.05). The cooking loss (%) was 24.38% in loin and it was lower than the other cuts (p<0.05). The bottom round had higher water holding capacity (WHC) and chuck tender had lower WHC than those in the other cuts (p<0.05). In meat color, L* values were higher in loin and lower in top round than the other cuts (p<0.05). Total saturated fatty acid contents were higher in loin and lower in bottom round than the other cuts (p<0.05). In amino acid compositions, top round had significantly higher than those in the other cuts (p<0.05). The iron contents were higher in chuck tender and chuck roll contained higher iron contents than those of the other cuts (p<0.05). In conclusion, the meat quality and nutritional properties were significantly different among 10 cuts in the same quality grade of Hanwoo beef. Therefore, the provision of the meat quality and nutritional information of 10 cuts to consumers could be important for utilization and balanced consumption of different cuts.

The objective of this research was to evaluate the changes of water-soluble flavor precursors in loin and top round from Hanwoo (Korean cattle) beef during aging at 2℃ for 14 days. The glycogen, glucose and lactate contents were not significantly influenced by beef parts and aging. Among nucleotide-related compounds, inosine 5'-phosphate (IMP) and inosine contents were significantly (p<0.05) lower in loin compared with top round but hypoxanthine content was not significantly different between beef parts. Moreover, during aging, IMP content significantly (p<0.05) decreased while inosine and hypoxanthine contents significantly (p<0.05) increased. It is concluded that aging highly affected the nucleotide-related compounds among water-soluble flavor precursors in loin and top round from Hanwoo.

근내지방도(IMF)가 한우육의 품질 및 기능성분에 미치는 영향을 조사하기 위하여, 250두의 한우를 근내지방 함량 에 따라 Low(<14%, n=96), Medium(14～17%, n=83), High(>17%; n=71) 세 그룹으로 분류하고, 7일간 숙성 후 등심육의 품질 및 기능성분을 분석하였다. 한우 등심육의 수분 함량은 IMF와 반비례하였으며, High IMF 그룹은 Low IMP 그룹 에 비하여 낮은 드립 감량을 나타내었다. 기능성 didpeptide 함량은 IMF에 따라 유의적 차이가 없었으나, High IMF 그룹은 다른 그룹보다 낮은 inosine monophosphate, 높은 hypoxanthine, 낮은 histidine 함량은 나타내었다. 불포화지방산 의 비율은 IMF에 따라 유의적 차이가 없었다. 저지방육의 건강지향적 가치를 고려할 때 지나친 IMF를 목표로 하는 육종 및 사양은 지양되어야 할 것으로 판단되었다.

This study was conducted to investigate the effect of age on the oxidative stability of Hanwoo (Korean cattle) cow beef. The samples of M. longissimus dorsi from 65 and 133 months-old-Hanwoo cows (4 and 3 heads, respectively) were stored at 4±0.2℃ for 9 days. The proximate composition, total myoglobin content, pH value, water-holding capacity and drip loss were not significantly affected by age. At day 9 of storage, the lipid oxidation (2-thiobarbituric acid reactive substances) was significantly (p<0.05) higher in beef from 133 months-old-cows than 65 months-old-cows. Lower (p<0.05) oxymyoglobin concentration and R630-R580 value and higher (p<0.05) metmyoglobin concentration were observed in beef from 133 months-old-cows at day 9 of storage than 65 months-old-cows. The CIE a*, b* and C* values were significantly (p<0.05) lowered in beef from 133 months-old-cows at day 9 of storage than 65 months-old-cows. It could be concluded that old age decreased the lipid oxidation stability and myoglobin oxidation stability in Hanwoo cow beef.

The objective of this study was to investigate the influence of parity on chemical composition and meat quality of Hanwoo cows (n=74, 2-15 years old). The beef loin and top round muscle samples were obtained and divided by 3 groups of parity numbers (G1, 0; G2, 1-3; G3, 4-9 times). Loin and top round from G1 had significantly higher intramuscular fat contents and lower protein contents than those from G3 (p<0.05). There was no significant difference in collagen contents among 3 parity groups (p>0.05). In meat color, G1 was higher in a* values for loin and higher in L* and a* values for top round muscle (p<0.05). The loin from G1 had significantly lower cooking loss (%) than G3, however, there was no significant difference in water holding capacity among 3 parity groups. For top round muscle, G3 had significantly higher Warner-Bratzler shear force values and lower water holding capacity values than G1 (p<0.05). In fatty acid composition, G1 had significantly higher C18:1n7 and C18:1n9 contents for loin, and it had significantly higher C16:1n7 and C18:1n7 contents for top round than those of the other groups (p<0.05). In free amino acid composition, alanine was highest and followed by glutamine, phenylalanine, isoleucine, proline, glycine, methionine. In conclusion, the parity conditions influenced on chemical composition and meat quality depending on different cut of Hanwoo cows, and the parity numbers were related with the age of cows.