• 한국축산식품학회지
• /
• 제40권1호
• /
• pp.34-43
• /
• 2020

The objectives of this study was to compare palatability changes of the longissimus thoracis (LT) and vastus lateralis (VL) muscles of Hanwoo steers from different beef quality grades (1⁺ and 1) during 28 d of wet-aging in order to improve the utilization of the VL muscle as a steak. The VL muscle showed a higher collagen content and a lower intramuscular fat content than the LT muscle (p<0.05). As expected, the Warner-Bratzler shear force value was greater in the LT 1 grade (LT-1) muscle than the LT-1⁺ muscle (p<0.05); whereas no difference was observed between the grades in the VL muscle at 24 h postmortem. Compared to 0 d of aging, tenderness scores significantly increased after 14 and 21 d of aging in the LT and VL muscles, respectively (p<0.05). Additionally, there was no difference in tenderness score between the VL-1⁺ aged for 21 d and the LT-1 at 24 h postmortem, although tenderness score was greater in the LT than the VL at each period (p<0.05). Moreover, the VL-1⁺ steak exhibited a higher tenderness score than the VL-1 steak at 21 and 28 d of aging (p<0.05). On the other hand, the effect of aging time on juiciness and flavor in the VL muscle was somewhat limited unlike the LT muscle. Taken together, the VL muscle requires a longer aging time than the LT muscle to improve consumer preference. Considering the tenderness, using a higher quality grade for aging is more useful in the VL muscle.

• Journal of Nutrition and Health
• /
• 제35권5호
• /
• pp.505-511
• /
• 2002

The study was designed to compare the anti-carcinogenic effect of different level of conjugated linoleic acid (CLA) in 1,2-dimethylhydrazine (DMH)-treated rats by determining biomarkers (apoptosis, cell proliferation, eicosanoids, 1,2-diacylglycerol) and phospholipid fatty acid profile in colonic mucosa. Eighty male Sprague Dawley rats weighing 180-220g were randomly divided into 4 groups depending on the content of CLA, i.e. 0.0% CLA, 0.5% CLA, 1.0% CLA, 1.5% CLA. The experimental diet contained protein 21.6%, carbohydrate 54.6%, and fat 14.5% including CLA mixture at different level by weight. The experimental diet was fed for 14 weeks with the initiation of intramuscular injection of DMH, which was injected twice a week for 6 weeks to give total amount of 180 mg/kg body weight. Regardless of the amount of CLA supplemented to diet, CLA significantly increased the apoptotic index but did not have significant effect on cell proliferation in colonic mucosa. CLA was undetected in colonic mucosal phospholipid of rats fed the 0% CLA diet and increased to 5.9mg/g phospholipid in rats fed the 0.5% diet. The apoptotic index was increased by 251% and the 1,2-DAG content was decreased by 57% in rats fed 0.5% CLA. No further changes in these variables were observed when CLA in the diet was raised to 1.0% or 1.5%. However, dietary CLA decreased mucosal levels of prostaglandin (PG)E$_2$, thromboxane (TX)B$_2$, and arachidonic acid in dose-dependent manner. The present data indicate that dietary CLA can inhibit DMH-induced colon carcinogenesis by mechanism probably involving increased apoptosis.

• Animal Bioscience
• /
• 제35권5호
• /
• pp.677-689
• /
• 2022

Objective: This study was conducted to evaluate the effects of concentrate level and chromium-methionine (Cr-Met) supplementation on the growth performance, carcass characteristics, meat quality, and fatty acid composition of Tan lambs. Methods: Sixty male Tan lambs (21±1.23 kg body weight) fed a finishing diet (concentrate-to-forage ratio: 35:65 [LC group] or 55:45 [HC group]) with daily Cr-Met supplementation (0, 0.75, or 1.50 g) were used in a completely randomized design with a 2×3 factorial arrangement of treatments. Results: Lambs from the HC group had higher average daily gain, dry matter (DM) digestibility, dressing percentages, leg proportions, intramuscular fat (IMF) contents, and saturated fatty acid levels, but lower feed conversion ratios, globulin (GLB) and total protein (TP) concentrations, shear force, and monounsaturated fatty acid (MUFA) levels (all p<0.05). Cr-Met supplementation increased the DM digestibility, GLB and TP concentrations, rack and loin percentages, and cooking loss, but decreased the IMF contents and leg proportions (all p<0.05). Cr-Met supplementation at 0.75 g/d increased the conjugated linoleic acid (CLA) content in both the HC and LC groups (p<0.01). Significant interactions between the concentrate level and Cr-Met dosage were observed for MUFA (p<0.01) and polyunsaturated fatty acid (PUFA) (p<0.01) levels. Meat from the lambs fed an unsupplemented LC diet presented the highest PUFA and MUFA levels (p<0.01). However, the MUFA and PUFA levels decreased significantly with increasing Cr-Met supplementation levels in the LC group (p<0.01), whereas the opposite trend was seen in the HC group. Conclusion: The HC diet improved the growth performance of Tan lambs, increased their profitability by increasing leg and rack joint proportions, and improved meat quality by promoting an IMF content that was more visibly acceptable to consumers. Cr-Met supplementation at 0.75 g/d in a HC diet was the best choice and may be economically beneficial.

• Animal Bioscience
• /
• 제36권9호
• /
• pp.1435-1444
• /
• 2023

Objective: This study was conducted to evaluate Raman spectroscopy technique as a noninvasive tool to predict meat quality traits on Braford longissimus thoracis et lumborum muscle. Methods: Thirty samples of muscle from Braford steers were analyzed by classical meat quality techniques and by Raman spectroscopy with 785 nm laser excitation. Water holding capacity (WHC), intramuscular fat content (IMF), cooking loss (CL), and texture profile analysis recording hardness, cohesiveness, and chewiness were determined, along with fiber diameter and sarcomere length by scanning electron microscopy. Warner-Bratzler shear force (WBSF) analysis was used to differentiate tender and tough meat groups. Results: Higher values of cohesiveness and CL, together with lower values of WHC, IMF, and shorter sarcomere were obtained for tender meat samples than for the tougher ones. Raman spectra analysis allows tender and tough sample differentiation. The correlation between the quality attributes predicted by Raman and the physical measurements resulted in values of R² = 0.69 for hardness and 0,58 for WBSF. Pearson's correlation coefficient of hardness (r = 0.84) and WBSF (r = 0.79) parameters with the phenylalanine Raman signal at 1,003 cm^-1, suggests that the content of this amino acid could explain the differences between samples. Conclusion: Raman spectroscopy with 785 nm laser excitation is a suitable and accurate technique to identify beef with different quality attributes.

• 한국식품과학회지
• /
• 제26권5호
• /
• pp.500-506
• /
• 1994

한우육(1등급), 유우육, 교잡종우육 및 호주산 수입우육의 등심부위를 구입하여 각종의 쇠고기 품질을 비교, 평가하기 위하여 연도, 다즙성 및 풍미에 관련되는 성분을 분석함과 아울러 관능검사를 실시하였다. 풍미에 관련되는 화학적 성분들로서는 비단백태질소, 핵산물질, 지방산, 유리아미노산 등을 분석하였고 쇠고기의 연도 측정을 위해 Hydroxyproline, 보수력, 근내지방함량 분석 및 Instron을 이용한 연도측정을 하였다. 또한 쇠고기의 기호성 및 풍미특성을 비교, 평가하기 위해 주관적 평가방법인 삼점검사와 정량적 묘사분석을 수행하였다. 풍미에 관련되는 비단백태질소, 핵산물질, 지방산, 유리아미노산 등을 분석한 결과, 비단백태질소는 한우육이 가장 낮아 도살후 저장기간이 가장 짧은 것으로 판단되며, 핵산물질은 한우육이 가장 높았다. 유리아미노산 함량은 한우육이 가장 낮았으나 염기성 아미노산과 방향족 아미노산의 상대적 비율은 가장 높았던 반면, 황함유 아미노산의 함량은 수입육이 가장 높았다. TBA가(價)는 한우육이 가장 낮았고, 지방산의 구성을 볼 때 한우육의 불포화지방산 비율은 수입우육이나 유우육보다 높았으나 교잡종우육과는 비슷하였다. 연도는 Instron을 이용한 경도측정에서 수입우육과 교잡종우육이 한우육과 유우육보다 질긴 것으로 나타났으며, 콜라젠 함량은 유우육이 가장 높았고 한우육이 가장 낮았다. 다즙성을 부분적으로 반영하는 보수력은 한우육이 가장 높았고 아울러 pH도 가상 높았다. 근내지방함량도 한우육이 가장 높아 다즙성이 우수한 것으로 판단되었다. 관능검사 결과, triangle test에서는 한우육과 수입우육, 한우육과 교잡종우육, 수입우육과 교잡종우육간의 차이를 관능검사요원들이 구별하였다. 그러나 정량적 묘사분석 결과 다즙성을 제외하고는 냄새, 풍미, 연도에서 품종간 차이가 발견되지 않았다. 한우의 비휘발성 풍미성분은 다른 쇠고기 시료에 비해 높은 경향을 나타냈음에도 불구하고 주관적 기호성 평가에서는 유의차를 나타내지 못했다. 이것은 한국인들이 아직 쇠고기 품질 특성에 대한 객관적 평가기준을 인식하지 못하고 있어 여러가지 쇠고기간의 비교평가는 할 수 있지만, 개별 쇠고기에 대한 절대평가는 제대로 할 수 없다는 것을 보여준다.

• 한국축산식품학회지
• /
• 제23권2호
• /
• pp.109-114
• /
• 2003

연도그룹에 따른 도체특성의 차이는 tender 그룹이 tough 그룹에 비해 무거운 도체중과 두꺼운 등지방 두께, 우수한 근내지방도, 밝은 육색, 흰 지방 및 좋은 조직감을 나타내었다(<0.05). 근절길이의 변화는 사후 시간이 경과함에 따라 지속적으로 감소하는 경향을 보였으며, 특히 사후 3시간 이후에 유의적으로 감소하였다(p<0.05). 연도에 따른 그룹간의 비교에서는 사후 3, 6 및 24시간에서 tender 그룹이 tough 그룹에 비해 유의적으로(p<0.05) 긴 근절길이를 나타내었다. 그리고 tender 그룹은 tough 그룹에 비해 낮은 IMCT 전단가를 나타내었고(p<0.05), 관능적으로 우수한 연도와 기호성을 나타내었다(p<0.05). 이상의 결과에서, 육의 연도는 다른 도체특성에 비해 등지방두께, 근내지방도 및 조직감과 밀접한 관련성을 보였으며, 사후초기인 3과 6시간에서의 근절길이를 측정함으로써 사후 24시간째 연도의 추정이 가능할 것으로 사료된다. 그리고 동일한 나이에서 연도와의 관련성은 총 콜라겐 및 가용성 콜라겐 함량보다는 근육내 결체조직의 강도와 더 높은 관련성 (p<0.05)이 있는 것으로 나타났다.

• Journal of Animal Science and Technology
• /
• 제65권6호
• /
• pp.1242-1253
• /
• 2023

The present study aimed to investigate the feasibility of using a diet low in lysine content as a means for increasing the intramuscular fat (IMF) content and pork muscle quality of finishing pigs. Thirty-two crossbred gilts and barrows weighing approximately 80 kg were fed either a low-lysine diet (0.60%; Low-lys) or a control diet (0.80% lysine; Med-lys) under a 2 × 2 factorial arrangement of treatments. The animals were slaughtered at a 132-kg body weight (BW) on average, followed by physicochemical analyses and sensory evaluation on Longissimus lumborum (LL) and Semitendinosus (ST) muscles. The average daily gain (ADG) did not differ between the Med-lys and Low-lys groups. However, ADG exhibited a tendency of sex × diet interaction (p = 0.09), being greater for barrows vs. gilts on the Low-lys diet (p < 0.05), but not on the Med-lys diet. Backfat thickness adjusted for 132-kg BW also exhibited the interaction; it was greater for the Low-lys vs. Med-lys group within gilts but tended to be less for the former in barrows (p = 0.08). The IMF content was not influenced by the diet or sex in either LL or ST. The a^*, b^*, and Warner-Bratzler Shear Force values and fatty acid composition were influenced by the sex or diet in either or both of the muscles, but the treatment effects did not apparently influence the meat quality. Sensory scores for the flavor, juiciness, tenderness, umami, and palatability of cooked muscle were not influenced by the diet in either LL or ST. When the LL and ST data were pooled, scores for those sensory attributes were positively correlated with the IMF content, which was associated with overall greater IMF contents and greater sensory scores for ST vs. LL. Collectively, the Low-lysine diet seemingly elicited the intended lysine deficiency in gilts as indicated by the increased BFT due to the diet. However, the Low-lys diet was not effective for increasing the IMF deposition or eating quality of the pork muscle of finishing pigs slaughtered at high BW probably because its lysine content was not low enough to elicit either outcome.

• Asian-Australasian Journal of Animal Sciences
• /
• 제26권11호
• /
• pp.1637-1643
• /
• 2013

The present work describes the effect of slaughtering age on horse carcass traits and on meat quality. Eighteen male Italian heavy draught horse (IHDH) breed foals were employed in the study. Soon after foaling they were randomly subdivided in 3 groups according to 3 age at slaughtering classes: 6 months old, 11 months old and 18 months old. Live weight, hot carcass weight and dressing percentage of each animal were recorded. After slaughtering, meat samples were collected from Longissimus Dorsi muscle between 13th and 18th thoracic vertebra of each animal and then analyzed. The right half carcass of each animal was then divided in cuts. Each one was subdivided into lean, fat and bones. Then, the classification of the lean meat in first and second quality cuts was performed according to the butchers' customs. Older animals were characterized by a lower incidence of first quality cuts (p<0.01) on carcass. Younger animals showed greater content in protein (p<0.01). Fatty acid profile showed an increasing trend of PUFA connected to the increasing of slaughtering age (p<0.05). The unsaturation index of intramuscular fatty acids was not affected by slaughtering age, confirming that horse meat, if compared to beef, is more suitable from a nutritional point of view. Season influenced reproduction, birth as well as production aspects of this species. The different slaughtering age could represent the way to produce meat of IHDH foals during the entire year without change in the qualitative standard expected by consumers.

• Asian-Australasian Journal of Animal Sciences
• /
• 제22권3호
• /
• pp.448-458
• /
• 2009

It has been well documented from animal and human studies that conjugated linoleic acid (CLA) has numerous beneficial effects on health. In chickens, CLA exerts many effects on performance ranging from egg quality and yolk lipids to meat quality. Although there are several CLA isomers available, not all CLA isomers have the same incorporation rates into egg yolk: cis-9,trans-11 and trans-10,cis-12 CLA isomers are more favorably deposited into egg yolk than other isomers investigated, but of the two isomers, the former has a higher incorporation rate than the latter. CLA alters the amounts and profiles of lipids in plasma, muscles and liver. Furthermore, increased liver weight was reported in chickens fed dietary CLA. As observed in egg yolk, marked reduction in intramuscular lipids as well as increased protein content was observed in different studies, leading to elevation in protein-to-fat ratio. Inconsistency exists for parameters such as body weight gain, feed intake, feed conversion ratio, egg production rate and mortality, depending upon experimental conditions. One setback is that hard-cooked yolks from CLA-consuming hens have higher firmness as refrigeration time and CLA are increased, perhaps owing to alterations in physico-chemistry of yolk. Another is that CLA can be detrimental to hatchability when provided to breeders: eggs from these breeders have impaired development in embryonic and neonatal stages, and have increased and decreased amounts of saturated fatty acids and monounsaturated fatty acids (MUFAs), respectively. Thus, both problems can be fully resolved if dietary sources rich in MUFAs are provided together with CLA. Emerging evidence suggests that CLA exerts a critical impact on stress and immune functions as it can completely nullify some of the adverse effects produced by immune challenges and reduce mortality in a dose-dependent manner. Finally, CLA is a key regulator of genes that may be responsible for lipid metabolism in chickens. CLA down-regulates both expression of the gene encoding stearoyl-CoA desaturase-1 and its protein activity in the chicken liver while up-regulating mRNA of sterol regulatory element-binding protein-l.

• Molecules and Cells
• /
• 제28권6호
• /
• pp.565-573
• /
• 2009

The pig could be a useful model to characterize molecular aspects determining several delicate phenotypes because they have been bred for those characteristics. The Korean native pig (KNP) is a regional breed in Korea that was characterized by relatively high intramuscular fat content and reddish meat color compared to other western breeds such as Yorkshire (YS). YS grew faster and contained more lean muscle than KNP. We compared the KNP to Yorksire to find molecular clues determining muscle characteristics. The comparison of skeletal gene expression profiles between these two breeds showed molecular differences in muscle. We found 82 differentially expressed genes (DEGs) defined by fold change (more than 1.5 fold difference) and statistical significance (within 5% of false discovery rate). Functional analyses of these DEGs indicated up-regulation of most genes involved in cell cycle arrest, down-regulation of most genes involved in cellular differentiation and its inhibition, down-regulation of most genes encoding component of muscular-structural system, and up-regulation of most genes involved in diverse metabolism in KNP. Especially, DEGs in above-mentioned categories included a large number of genes encoding proteins directly or indirectly involved in p53 pathway. Our results indicated a possible role of p53 to determine muscle characteristics between these two breeds.