• Asian-Australasian Journal of Animal Sciences
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• 제33권1호
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• pp.157-165
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• 2020

Objective: The objective of this study was to compare the quality of dry-aged beef from cull Hanwoo cows slaughtered at 60 or 80 months old. Methods: A total of eight cull Hanwoo carcasses with a quality grade of 3 (low-grade) were selected and divided into two age groups: 63.5±2.5 months old (n = 4) and 87.8±4.5 months old (n = 4). Whole longissimus thoracis et lumborum from the 11th rib to the last lumbar vertebrae, including the back fat, was removed from the carcass at 24 h postmortem and aged for 50 days in darkness at a temperature of 2℃±1℃, a relative humidity of 85% and an air flow of 2 m/s. The sampling was performed aseptically after 0, 20, 24, 40, and 50 days of aging. Results: Regardless of the aging period, aging increased the lightness (p<0.05), redness (p<0.05) and yellowness (p<0.05) at initial blooming (90 min after slicing) and the overall acceptance (p<0.05). No further tenderization effect was found after 20 days of aging, but aging for 50 days significantly increased the lipid oxidation (p<0.05). The generation of aroma volatiles in the roast steak from aged samples was higher (p<0.05) than that of non-aged samples. No significant effect of age at slaughter was found on the color, pH, water-holding capacity, cooking loss, shear force value, bacterial counts, volatile basic nitrogen, consumer acceptance, lipid oxidation, fatty acid composition or aroma volatiles. Conclusion: The quality of dry-aged beef obtained from cull Hanwoo cows slaughtered at either 60 or 80 months old with similar quality grade was comparable and extending dry aging for more than 40 days is not recommended considering the costs and further lipid oxidation.

• 한국식생활문화학회지
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• 제27권5호
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• pp.422-433
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• 2012

The purpose of this study was to investigate changes in Korean meat consumption as well as meat consumption trends. During the Japanese occupation period, the supply of meat was considerably insufficient. However, meat consumption mainly in large cities has gradually increased. Especially, 'Pyeongyang cow', a specialty of Pyeongyang, started being raised as edible beef cattle in 1933. During the chaotic period following liberation from Japan, the price of meat sharply increased. However, as the meat supply stabilized, the 'beef grade system' was introduced in 1967. Since then, beef has sold according to region. During the early economic growth period of the mid-1970s, meat consumption rapidly increased, and foreign beef was first imported in 1976. The preference for beef was somewhat attenuated due to the outbreak of mad cow disease and economic slowdown of the 1990s, resulting in an increase in the consumption of pork, a replacement meat. During the recent period of economic development, meat consumption has somewhat fallen and remained low. In late 2003, with the occurrence of mad cow disease in the US, the demand for pork, and especially pork fatback, has sharply increased.

• 한국축산식품학회지
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• 제39권6호
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• pp.934-942
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• 2019

Previous studies on dry aged beef, which substantially increases the value of low-grade raw beef and non-preferred cuts, are currently limited to the observation of aged beef changes in laboratory settings or under particular aging conditions, whereas the factors influencing aging have so far been underexplored. Herein, we attempt to establish a technique for distinguishing between fresh and aged beef by observing changes in quality during beef aging. Specifically, we analyzed the effect of time on the quality of aged beef sourced from three Korean manufacturers and identified quality indicators that can be used to distinguish between fresh and aged beef, regardless of supplier. Storage/trimming/aging/cooking losses, moisture/fat/protein/collagen contents, and water holding capacity were tested as potential indicators, among other parameters. As a result, the quality of dry aged beef was shown to be supplier-dependent, which made the identification of factors for the above origin-independent discrimination difficult. Nevertheless, as storage loss, water holding capacity, and cooking loss significantly changed with dry aging time in all cases, these parameters were concluded to be potentially suited for discrimination purposes. The insights gained in this work may help promoting further research in this field and contribute to the development of a standard for consistent aged beef production.

• 한국축산식품학회지
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• 제36권5호
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• pp.679-688
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• 2016

The aim of this research was to evaluate: 1) the fatty acid profile of ten muscles from high marbled (HM, quality grade 1⁺⁺) and low marbled (LM, quality grade 2) Hanwoo carcass, 2) the relationship between the fatty acid profile and sensory traits. There were significant (p<0.001) differences in fat content and fatty acid composition among the 10 muscles obtained from HM and LM Hanwoo steers. The proportions of SFA (saturated fatty acid), MUFA (monounsaturated fatty acid) and PUFA (polyunsaturated fatty acid) were significantly (p<0.001) different among the 10 muscles due to differences in all fatty acids except eicosapentaenoic acid (EPA, C20:5n-3). The high-fat muscles had a lower n-6/n-3 ratio compared to the low-fat muscles (p<0.001). LM muscles had a significantly (p<0.05) higher proportion of SFA than HM muscles due to a higher proportion of stearic acid (C18:0). On the contrary, HM muscles had a significantly (p<0.01) higher proportion of MUFA than LM muscles due to higher oleic acid (C18:1n-9) proportion. SFA had a significant correlation with CIE a* (r=0.281; p<0.01) and drip loss (%) (r=−0.233; p<0.001). Cooking loss (%) had a significantly (p<0.05) negative correlation with PUFA (r=−0.233; p<0.05). Overall palatability was positively correlated with SFA (r=0.262; p<0.01), but negatively correlated with PUFA (r=−0.567; p<0.001). There was no significant correlation between oleic acid and any of the sensory traits (p>0.05).

• 한국식품영양학회지
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• 제28권3호
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• pp.415-421
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• 2015

This study investigated the quality change of strip loin from hanwoo with quality grade 2 produced by dry aging, and compared the quality of dry-aged strip loin with that of strip loin from hanwoo with quality grade $1^+$. Hanwoo strip loins with quality grade $1^+$ (SL1) and 2 (SL2) after a day of slaughter and dry-aged strip loin (DSL2) aged for 21 days at $2^{\circ}C$ with 85% humidity were obtained from local markets. The proximate composition, pH, cooking loss, lipid oxidation, instrumental color (CIE $L^*$, $a^*$ and $b^*$ value) and sensory properties of the strip loins were measured. DSL2 contained low moisture and high protein contents compared with SL2, and low fat, high protein, and high ash contents compared with SL1 (p<0.05). The pH and cooking loss were higher and lower, respectively, in DSL2 compared to SL2 (p<0.05). SL1 had a higher pH than DSL2 (p<0.05). However, the cooking loss was not different between SL1 and DSL2. The TBARS value was the highest in DSL2 and the lowest in SL2 (p<0.05). DSL2 had higher $L^*$ and $b^*$ value compared with SL2 (p<0.05). There were no significant differences of $L^*$, $a^*$ and $b^*$ values between DSL2 and SL1. Sensory properties such as the color, flavor, taste, texture, and acceptability of DSL2 were higher than those of SL2 (p<0.05). There was no significant different in all sensory properties between DSL2 and SL1. According to the results, dry aging can improve the nutritional and sensorial quality of strip loin with quality grade 2 to quality comparable to quality grade $1^+$.

• Asian-Australasian Journal of Animal Sciences
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• 제29권8호
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• pp.1083-1094
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• 2016

Carcass and price traits of 72,969 Hanwoo cows, bulls and steers aged 16 to 80 months at slaughter collected from 2002 to 2013 at 75 beef packing plants in Korea were analyzed to determine heritability, correlation and breeding value using the Multi-Trait restricted maximum likelihood (REML) animal model procedure. The traits included carcass measurements, scores and grades at 24 h postmortem and bid prices at auction. Relatively high heritability was found for maturity ($0.41{\pm}0.031$), while moderate heritability estimates were obtained for backfat thickness ($0.20{\pm}0.018$), longissimus muscle (LM) area ($0.23{\pm}0.020$), carcass weight ($0.28{\pm}0.019$), yield index ($0.20{\pm}0.018$), yield grade ($0.16{\pm}0.017$), marbling ($0.28{\pm}0.021$), texture ($0.14{\pm}0.016$), quality grade ($0.26{\pm}0.016$) and price/kg ($0.24{\pm}0.025$). Relatively low heritability estimates were observed for meat color ($0.06{\pm}0.013$) and fat color ($0.06{\pm}0.012$). Heritability estimates for most traits were lower than those in the literature. Genetic correlations of carcass measurements with characteristic scores or quality grade of carcass ranged from -0.27 to +0.21. Genetic correlations of yield grade with backfat thickness, LM area and carcass weight were 0.91, -0.43, and -0.09, respectively. Genetic correlations of quality grade with scores of marbling, meat color, fat color and texture were -0.99, 0.48, 0.47, and 0.98, respectively. Genetic correlations of price/kg with LM area, carcass weight, marbling, meat color, texture and maturity were 0.57, 0.64, 0.76, -0.41, -0.79, and -0.42, respectively. Genetic correlations of carcass price with LM area, carcass weight, marbling and texture were 0.61, 0.57, 0.64, and -0.73, respectively, with standard errors ranging from ${\pm}0.047$ to ${\pm}0.058$. The mean carcass weight breeding values increased by more than 8 kg, whereas the mean marbling scores decreased by approximately 0.2 from 2000 through 2009. Overall, the results suggest that genetic improvement of productivity and carcass quality could be obtained under the national scale breeding scheme of Korea for Hanwoo and that continuous efforts to improve the breeding scheme should be made to increase genetic progress.

• 대한영양사협회학술지
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• 제2권1호
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• pp.69-80
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• 1996

This study was performed to investigate the food preference trends of the children according to age increase and change of the times. The subjects were 1,450 children who are fifth grade of primary school and 2,000 juveniles who are senior high school in 1993. This survey data were compared with the Food preference study of the primary school aged children in 1987.' The results of this study can be summarized as follows 1. State of the general taste The subject had a high preferences to bulgogi(roast beef), panbroiled cuttlefish, steamed egg, fried sausage and donuts among the all sorts of 165 principal and subsidiary foods. But, fried beef liver, pancake, sweet potato with syrup, spinach soup and boiled rice with red bean didn't suit for their taste. Compared with survey data done in 1987, in present study significantly increased preferences to steamed food, pan frying and parboiled vegetables were shown. Particularly, food preference was changed with the cooking methods rather than materials. 2. Differences of the preference according to change of the times In present study, except the rice cakes preferences to all sorts of foods were improved and markedly increased preferences to steamed food, parboiled vegetables and mixed with seasonings were observed. Compared with 87's study deviation of the preference to cooking materials was decreased considerably. Preferences to salty tasted foods as like as stew and salted food were low no better than before. 3. Changes of preference according to age increase Among the principal foods, increased preferences to boiled rice and cereals were shown but to one-dish meal, bread and rice cake were decreased. Among the subsidiary foods, significantly decreased preference to frying was observed. Irrespectively of the cooking methods, preferences to fish and vegetables were improved. And in the frying and panbroiled foods, deviation of preferences to cooking materials were considerable, which means the fixation of food behavior.

• Nutritional Sciences
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• 제7권2호
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• pp.113-120
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• 2004

This study was conducted to investigate variables related to dietary fiber intake among sixth grade children in an elementary school in Daejon city. One hundred and forty-seven children completed a questionnaire for determining their socioeconomic background and their food habits. Anthropometric measurements were taken, and a 24-hour diet recall method was used to collect three-day food intakes. The socioeconomic status of the children's families belonged to the upper middle class; 53.0% of their fathers and 25.8% of their mothers had completed college or higher degrees. 27.9% of the mothers had jobs, including part-time jobs. Approximately 30% of the children skipped breakfast, 66.4% of the children preferred animal foods to plant foods, and 52.4% of the children preferred green vegetables to yellow or pale vegetables. Grilled meat dishes, such as Grilled beef rib with seasoning, Bulgogi, grilled pork belly and beef steaks, were the most popular types of food eaten outside home by the children. Daily dietary fiber intake was 14.5 g in boys and 14.5 g in girls, and these intakes are low compared to the standard guidelines. The average intakes of energy and protein of the children were 84.5% and 114.0% of the Korean Recommended Dietary Allowances (RDAs), respectively. Besides energy, riboflavin, iron and calcium intakes were below the RDAs, and especially calcium intake was only 50% of the RDAs. On the other hand, thiamin, niacin, ascorbic acid, protein and phosphorus intakes exceeded the Korean RDAs. Family income or the children's body mass index (BMI) was not directly related to dietary fiber intakes. However, higher dietary fiber intakes tended to be related to higher intakes of green vegetables and fruits. Children with higher dietary fiber intake tended to prefer plant foods to animal foods. Energy and most nutrients, except heme iron and retinol, showed positive relationships with dietary fiber intake. Especially potassium and plant origin protein and calcium were highly correlated with dietary fiber intakes(r＞0.6). From these results, it is concluded that dietary fiber intakes of these sixth grade elementary school children were less than the standard reference and it is anticipated to decrease further in the future with increased incomes. Therefore, increased intakes of dietary fiber by elementary school children should be promoted through nutrition education, together with the development of cooking methods and recipes utilizing green vegetables and fruits.

• Asian-Australasian Journal of Animal Sciences
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• 제8권3호
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• pp.281-287
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• 1995

A study was conducted to investigate the effect of different inclusion levels of urea treated whole-crop wheat silage (UWCWS) in grass silage based rations on the performance of growing beef cattle. The winter wheat (variety, Riband) was harvested (in the summer of 1991) at a dry matter proportion of 520 g/kg and treated with feed grade urea at the rate of 37 kg/tonne crop dry matter and preserved in a heavy duty plastic bag using a silo press. The urea treated whole crop wheat silage (UWCWS) was mixed with grass silage to replace 0.00 (S100), 0.33 (S33) and 0.67 (S67) parts of the forage dry matter and fed ad libitum in a cross over design to 18 Simmental X Holstein Friesian growing beef animals. Two energy sources {one high in starch, rolled barley (RB) and one high in digestible fibre, sugar beet pulp (SBP)} were fed to supply sufficient energy for the efficient use of nitrogen by the rumen micro-organisms. The data on DMIF (dry matter intake of forage), TDMI (total dry matter intake), DLWG (daily live weight gain), FCR (feed conversion ratio) were recorded and faecal samples were collected to determine the digestibility coefficients. Results revealed that with the inclusion of UWCW in the animals' diets the DMI of the forage was significantly increased (p < 0.05). The highest DMIF was found in the treatment "S33" ($6.28{\pm}0.25kg$) where 67% of the silage dry matter was replaced with the UWCW and the lowest value for DMIF was observed in the control treatment ($5.03{\pm}0.23kg$). The DLWG did not differ significantly between the treatments. However, treatment "S100" showed a trend towards a superior DLWG. Feed conversion ratio in the control treatment differed significantly from "S67" and "S33". The addition of the UWCW in the animals' diet resulted in the lower FCR There was no effect of type of energy supplement on any aspect of performance either overall or in interaction with grass silage: UWCWS ratio. The regression and correlation coefficients for DMIF (r = 5.22 + 0.0184x*), DLWG (r = $1.04-0.00086x^{NS}$) and FCR (r = 4.78 = 0.022x*) on the inclusion of UWCW in the diet were calculated. The effect of the inclusion of UWCW on the overall digestibility coefficients was significant (p < 0.05). The addition of the UWCWS in the diet decreased the digestibility of the DM, OM, ADF and NFE but effect on the protein digestibility was non significant. The results of present study suggests that a DLWG slightly over 1 kg can be achieved with UWCW during the store period (period in which animal performance targets are low especially during winter) and the prediction of ME was overestimated as the high intake of DM did not reflect in improved animal performance.

• 한국초지조사료학회지
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• 제35권1호
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• pp.12-16
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• 2015

본 시험은 TMR 사료의 물리적유효섬유소(peNDF) 함량의 차이가 한우 비육거세우의 생산성과 도체특성에 미치는 영향을 검토하여 TMR 사료내 적정 조사료가치 평가를 위해 실시하였다. 공시가축은 26개월령의 한우 거세우 12마리이고, 물리적유효 NDF (peNDF) 함량이 높은 처리구(High군)과 낮은 처리구(Low군)의 2개 군을 이용하여 출하시까지 사양실험을 실시하였다. 실험에 사용한 비육후기용 TMR 사료는 물리성 처리를 위해 배합시간을 3분(High)과, 25분(Low)으로 처리하였다. 실험동물은 출하한 후 축산물 품질평가원에서 도체평가를 하였다. 실험기간 중 체중증가(P<0.05) 및 일당증체량은 High 구에서 높았으며, 유의성은 인정되지 않았으나 도체중 역시 High 구가 $414.60{\pm}34.28kg$으로 Low 구의 $377.80{\pm}11.97kg$ 보다 높게 나타났다. 육질등급은 High 구가 평균 $1^+$ 등급이었던 것에 비해 Low구는 평균 $1^{++}$ 등급으로 오히려 육질 등급은 Low 구에서 높은 것으로 나타났다. High 구는 채식량과 체내 이용성에 영향을 미쳐 체중 증가와 일당 증체량 및 도체중의 증가를 가져와 생산성은 증가되었으나 등지방두께의 증가 및 육질 등급에서는 다소 저하를 가져오는 것으로 분석되었다. 따라서 한우 거세 비육우에 있어서도 사료 내의 물리적 유효 섬유 함량은 가축생산성과 도체특성에 영향을 미치고 있기 때문에 그에 대한 적정 함량의 규명이 필요할 것으로 판단된다.