• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.5
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• pp.493-501
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• 1986

The present work aims to estimate the effect of heat treatment on the in vitro protein digestibility and formation of trypsin inhibitor or trypsin indigestible substrate(TIS) of raw and defatted flounder. It was also carried out to assess the formation of lipid-protein complexes under the conditions of different ratio of lipid addition. The in vitro protein digestibility increased when steamed for 5 min showing $88.09\%$ in raw and $90.56\%$ in defatted samples, respectively. After 40 min steaming, the digestibility decreased by $2{\sim}4\%$. As for microwaving, heating for 1 min resulted in slight increase of digestibility, however, heating for 7 min did decrease of digestibility by $3{\sim}4\%$ for both raw and defatted materials. There was no difference in fatty acid composition found with heat treatment. The major fatty acids of flounder meat were $C_{16:0},\;C_{16:1},\;C_{18:1},\;C_{20:5},\;C_{22:6}$ and the ratio of the unsaturated to saturated was 67.3:32.6. Fat oxidation and nonenzymatic browning were enhanced by heat treatment and protein solubility decreased necessarily as the brown pigment formation increased. On the other hand, the effects on the digestibility and TIS of the complexes formed from interaction of lipid and myofibrillar or meat protein of flounder were examined. The interaction of protein with lipid was considered to mostly contribute to the drop of digestibility of fish products. The digestibility of myofibrillar protein was $93.72\%$ for flounder, and it generally decreased as the amount of lipid added to protein and reaction time increased. Also mixed and heated samples were more active in digestibility decline than those mixed after heating. The result probably indicated that lipid-protein interaction was involved in the drop of digestibility which coincided with protein denaturation.

• Korean Journal of Agricultural Science
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• v.43 no.5
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• pp.810-817
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• 2016

The aim of this experiment was to determine the effect of a high-energy diet on the level of serum metabolites and on carcass characteristics of Hanwoo steers. High energy diets have been used for enhancing intramuscular adipose tissue in high quality beef cattle. However, there is not much information about the physiological reactions to this diet. We hypothesized that a high energy diet would increase blood metabolites and the meat quality of Hanwoo steers during the early and final fattening periods. A $2{\times}2$ factorial arrangement (High, Control, and Early, Final) in a completely randomized design was used to feed 24 Hanwoo steers. Two steers were kept in the same pen and 12 pens were used for the experiment. Blood was drawn from each steer on the first week of every other month from 11 to 28 months. Overall Average Daily Gain (ADG) and feed efficiency were not different between high energy and control diets (p > 0.05). However, Dry Matter Intake (DMI greater with the control diet than DMI with the high energy diet during the final fattening period (p < 0.05). Serum non-esterified fatty acid (NEFA) concentrations were greater in the control diet group than in the high energy diet group during the final fattening period (p < 0.05). However, serum albumin, glucose, total protein, triglyceride, and phosphorus were greater in the high energy group than those of the control group (p < 0.05). Carcass traits or physico-chemical characteristics were not different between high energy diet treatment and the control. These data indicated that a high energy diet (+ 3% TDN) increased serum triglyceride during early fattening periods and decreased non-esterified fatty acids during final fattening periods in Hanwoo steers.

• Korean Journal of Agricultural Science
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• v.45 no.1
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• pp.84-93
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• 2018

This study was conducted to develop a pasture feeding program for reducing the Hanwoo feeding cost. Italian ryegrass (IRG) is a major plant which is abundantly produced in the southern area of South Korea. Locally produced Italian ryegrass has a 30 - 50% reduced pasture cost compared to imported pasture grasses. We hypothesized that Italian ryegrass feed could reduce the feeding cost but not change the physiological characteristics of the Hanwoo steers in the feedlot. Four treatments (Control, short fed IRG silage, long fed IRG silage, and IRG hay) in a completely random design were used to feed 27 Hanwoo steers. Three or four steers were fed in the same pen, and 8 pens were used for the treatments. Blood was drawn from each steer on the first week of every month from 11 to 30 months. Overall, the average daily gain and feed efficiency were not different among the treatments (p < 0.05) except for the final fattening diets (p < 0.05). The long fed IRG silage group had a low ADG compared to the other groups (p < 0.05). The serum non-esterified fatty acid and glucose concentrations were reduced during the fattening periods (p < 0.05); however, the serum albumin, total proteins, triglycerides, and phosphorus were increased during the fattening periods (p < 0.05). The carcass weight, longissimus muscle area and back-fat thickness were low in the long fed IRG silage group (p < 0.05). The IRG diet induced saturated fatty acids in the longissimus dorsi (p < 0.05). These results show that the IRG diet increased the serum triglycerides but reduced the glucose level at the final fattening diet and decreased the meat yield score in Hanwoo steers.

• Journal of Animal Science and Technology
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• v.58 no.6
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• pp.23.1-23.17
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• 2016

Background: The functionality of myofibrillar proteins is a major factor influencing the quality attributes of muscle foods. Nonetheless, the relationships between muscle type and oxidative changes in chevon during ageing are meagrely elucidated. Postmortem changes in antioxidant status and physicochemical properties of glycolytic gluteus medius (GM) and oxidative infraspinatus (IS) muscles in goats were compared. Methods: Twenty Boer bucks (9-10 months old, body weight of $36.9{\pm}0.725kg$) were slaughtered and the carcasses were subjected to chill storage ($4{\pm}0.5^{\circ}C$). Analyses were conducted on GM and IS muscles sampled on 0, 1, 4 and 7 d postmortem. Results: Chill storage did not affect the antioxidant enzyme activities in both muscles. The IS had greater (P < 0.05) superoxide dismutase and catalase activities than GM. Carotenoid and tocopherol contents did not differ between muscles but decreased (P < 0.05) over storage. The IS had higher (P < 0.05) glycogen and ultimate pH and lower (P < 0.05) shear force and cooking loss than GM. The carbonyl content, % metmyoglobin, drip loss and TBARS increased (P <0.05) while free thiol, metmyoglobin reducing activity (MRA), shear force and myoglobin decreased (P < 0.05) over storage. Muscle type had no effect (P > 0.05) on free thiol, MRA and TBARS. The GM had lower (P < 0.05) redness on d 0 and 1 than IS while the IS had greater carbonyl, % metmyoglobin and drip loss than GM on d 7. The reflective density of slow myosin heavy chain (MHC) was higher (P < 0.05) while the density of fast MHC and actin was lower (P < 0.05) in IS than GM. Regardless of muscle type, the density of MHC decreased (P < 0.05) while that of actin was stable over storage. Nonetheless, the degradation of fast and slow MHC was greater (P < 0.05) in IS than GM. Muscle type had no effect (P > 0.05) on consumer preference for flavour, juiciness and overall acceptability. However, IS had higher (P < 0.05) tenderness score than GM on d 1 and 4 postmortem. Intramuscular fat was higher (P< 0.05) in IS compared with GM. Fatty acid composition did not differ between the muscles. However, GM had lower (P < 0.05) n-6/n-3 ratio than IS. The n-3 and n-6 PUFA declined (P < 0.05) while the SFA increased (P < 0.05) over storage. Conclusion: The changes in myofibrillar proteins and physicochemical properties of goat meat during postmortem chill storage are muscle-dependent.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.2
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• pp.290-297
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• 2012

The nutritional composition of thawed Hanwoo beef fed no mugwort (T0) and thawed Hanwoo beef fed mugwort (T1) were analyzed after freezing at $-20^{\circ}C$ for 12 months. Also the effect of feeding mugwort was investigated by comparing physicochemical and palatability changes by chilling the beef after thawing. There were no significant differences in general components of T0 and T1 Hanwoo beef. Among the minerals, there were no significant differences in the contents of Ca, P, K, Mg and Zn, however Na content in T0 and Fe content in T1 were significantly higher. The total amino acid did not show a significant difference but leucine was found to be higher in T0 than T1, and glycine, cysteine, histidine and arginine were higher in T1 than T0. Regarding fatty acids, stearic acid was higher in T0, while palmitoleic acid, oleic acid and total unsaturated fatty acid was significantly higher in T1. The hardness value became lower by chilling after thawing regardless mugwort consumption, and therefore the tenderness improved. The freshness, fat rancidity and antioxidant activity of thawed Hanwoo beef changed more slowly for T1 than T0, which indicates that feeding mugwort had a positive effect. There were no significant differences in taste, juiciness, tenderness or and palatability of the cooked beef between T0 and T1 for both 0 days and 3 days after thawing. However, the aroma of cooked T1 beef was significantly superior.

• Food Science of Animal Resources
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• v.29 no.6
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• pp.685-694
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• 2009

The aim of the present study was to evaluate the variation in ultimate pH of commercial populations of pure-breed (Landrace, Duroc and Yorkshire) pig's longissimus muscles and their effect on objective meat quality traits and sensory characteristics. Fifty boars were sampled from 184 pigs, which were reared at three breeding farms and slaughtered at a commercial abattoir. The selection was determined based on ultimate pH, and animals were segregated into three groups: low pH (pH $\leq$ 5.5, n=13), medium pH (pH 5.5 to 5.6, n=18) and high pH (pH $\geq$ 5.6, n=16). The breeds had no significant effects; however, pigs with a higher ultimate pH had significantly (p<0.05) higher intramuscular fat content, lower level of polyunsaturated fatty acids, lower level of lipid oxidation and higher eating quality compared to those with lower ultimate pH. As the ultimate pH increased, the relative proportion of C14:0, C16:0 and C18:1 increased while C18:2n6 and C20:4n6 decreased. The present study demonstrates that the economic value of pigs can be characterized by the ultimate pH and/or intramuscular fat content. However, these results do not necessarily indicate that a high ultimate pH directly corresponds to high intramuscular fat content and vice versa.

• Animal Bioscience
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• v.37 no.8
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• pp.1452-1462
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• 2024

Objective: This study aimed to investigate the effects of dietary supplementation with Agaricus blazei polysaccharide (ABP) at varying concentrations on the performance, egg quality, blood biochemistry, intestinal morphology, and microflora of quail. Methods: The study involved a total of 2,700 Korean quails, which were randomly divided into three groups. The measured variables encompassed productive performance, egg parameters, carcass parameters, serum metabolites, immune response parameters, antioxidative properties, and gut microbiome. Results: The addition of ABP did not have a significant effect on average daily feed intake. However, it was found to increase the average daily egg weight and egg production rate, reduce the feed-egg ratio. There were no significant impacts on egg quality measures such as egg shape index, egg yolk index and color, egg yolk and protein content. However, ABP supplementation significantly increased the Hough unit (p<0.01) and decreased the rate of unqualified eggs (p<0.01). Regarding serum parameters, the inclusion led to an increase in total protein concentration (p<0.05) and a reduction in low-density lipoprotein cholesterol (p<0.05). There were no significant effects observed on immune indicators such as immunoglobulin A (IgA) and IgM. ABP supplementation increased the levels of serum antioxidant indicators, including glutathione peroxidase, total superoxide dismutase (p<0.05), and total antioxidant capacity colorimeter (p<0.05). Furthermore, ABP supplementation significantly elevated the intramuscular fatty acid content in quail meat. Additionally, ABP supplementation demonstrated a significant improvement in the diversity of gut microbiota and induced alterations in the composition of the gut microbiota. Conclusion: The findings of this study indicate that dietary supplementation of ABP enhanced production performance and antioxidant capacity while increasing the levels of polyunsaturated fatty acids in quail muscle.

• Journal of Animal Science and Technology
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• v.46 no.4
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• pp.659-666
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• 2004

This study was conducted to assess objective and subjective meat quality traits for imported chilled beef with a high degree of marbling in longissimus muscle with reference to Hanwoo beef Muscle samples of four Wagyu, four Angus, four Hanwoo grade 1, and three Hanwoo grade 3 were purchased from a commercial beef market. The meats had intramuscular fat content of approximately 22, 8, 13 and 4%, and aged for 31, 71, 14 and 14 days, respectively. Imported beef showed a significantly(P<0.05) lower WB-shear force than Hanwoo. However, the instrument measurement did not reflect sensory tenderness and juiciness, which were similar between the four groups. On the other hand, Hanwoo beef showed significantly(P<0.05) favorable flavor intensity. This was likely an indication of more a desirable eating quality for Hanwoo beef, regardless of the level of intramuscular fat content. Discriminant functions of C18: 0, C18: In-7, C18: In-9, C20: 3n-6, C20 : 4n-6 and total n-3 polyunsaturated fatty acids classified the domestic and foreign beef products at 100%, despite a noticeable difference between two groups existed only in C18:0. Principle component analysis indicated that subjective flavor intensity was negatively related to C18: 0 and C18: ln-7. The result indicated that C18: 0 could be a possible candidate fatty acid for difference in flavor intensity between two beef groups. The current study demonstrated that the domestic product was more acceptable for Korean consumers. However, it was not identified whether the result was associated with breed, feeding regime, or ageing time. Further studies are required for breed specification in terms of sensory characteristics and consumer preference.

• Korean Journal of Poultry Science
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• v.40 no.1
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• pp.57-65
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• 2013

This study was conducted to evaluate the effect of dietary Weissella koreensis (Wk), a prominent kimchi lactic acid bacteria supplementation on growth performance, nutrients utilization, gut microbiota and meat characteristics in broiler chicken. Both live and killed Wk was compared to know which could be more efficacious as a feed probiotics. Three Wk supplemented groups and no Wk supplemented group were designated according to supplementation levels and cell status. Those were; Control (no Wk), 0.1 % live Wk (LWk 0.1), 0.5% live Wk (LWk 0.5) and 0.5% killed Wk (KWk 0.5). Body weight gain and feed conversion efficiency were improved (P<0.05) by dietary LWk supplementation. KWk did not exert any benefit on growth performance. Crude protein utilizability of KWk supplemented diet was lower (P<0.05) than that of other diets. However, there were no differences among treatments in other nutrients utilization. Serum IgG concentration and relative weight of bursa of Fabricius was highest (P<0.05) in broiler chicken fed KWk 0.5 diet. Cecal anaerobic lactic acid bacteria count of LWk groups were higher (P<0.05) than those of control and KWk 0.5 groups. Dietary Wk supplementation failed to lower the count of cecal and fecal E. coli. There was no effect of dietary Wk on TBARS values and fatty acids profile of broiler leg meat. However, the dietary supplementation of Wk exerted characteristic difference on electronic nose flavor of broiler meat. This study showed that dietary supplementation of LWk was able to improve body weight gain, feed conversion efficiency and cecal lactic acid bacterial count in broiler chicken. Further, the result of this study implemented that a live kimchi lactic acid bacteria, LWk, but not killed Wk, could be used as a probiotic feed supplement for broiler.

• Korean Journal of Poultry Science
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• v.34 no.4
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• pp.319-327
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• 2007

This experiment was designed to evaluate effects of Dandelion (Taraxzcum coreanum) and Dandelion fermented probiotics medium on the growth performance and meat quality in broiler chicks. A total of 150 "Ross" broilers，1-day old, were assigned to 5 treatments in a completely randomized design. There were 5 replications per treatment and 6 broilers in each replication for 5 weeks. The dietary treatments included a control (Dandelion and Dandelion fermentation was not added), antibiotic (0.05 chlortetracycline was added), 1.0% Dandelion supplementation and 0.5 and 1.0% Dandelion fermented probiotics, respectively. There was no significant difference in final body weight, weight gain, feed intake, and feed conversion ratio of broilers fed diets containing antibiotics, 1.0% Dandelion supplementation and 0.5 and 1.0% Dandelion fermented probiotics. The total cholesterol, HDL and LDL in plasma and meat cholesterol content was not affected by 0.5 and 1.0% Dandelion fermented probiotics and 1.0% Dandelion supplementation (P>0.05). The oleic acid content was significantly increased in 0.5% Dandelion fermented probiotics compared to that of the control (P<0.05). As a result, Dandelion and Dandelion fermented probiotics result in the influence on decreasing cholesterol in blood, particularly when adding probiotics, oleic acid that is the important factor in taste testing of meat increases thus the quality and taste of the chicken meat could be improved with the effect.