• Korean Journal of Poultry Science
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• v.43 no.4
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• pp.197-206
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• 2016

This work was carried out to investigate effects of the freezing/thawing method on duck meat kept in a freezer for a month. The meats used were breast muscle collected from Korean native ducks (KND) that were fed for 8 weeks (2.8 kg of live weight). Forty-five samples were used after being frozen in storage for one month and were then divided into 5 treatments (3 replications/treatment, 3 samples/replication). Five treatments (CON, FFFT, FFST, SFFT and SFST) were control groups (CON) and four were experimental groups, using $2{\times}2$ complex factors with two freezing methods (fast freezing, FF, $-50^{\circ}C$ in a deep freezer; slow freezing, SF, $-20^{\circ}C$ in a common freezer) and two thawing methods (fast thawing, FT, 5 h $12^{\circ}C$ with flow water; slow thawing, ST, 24 h $5^{\circ}C$ in a refrigerator). Lightness of KND meat in FF and FT groups was lower than that of control (P<0.05). Yellowness of KND meat of the ST group was higher than that of control (P<0.05). Cooking loss (CL) and water holding capacity (WHC) of KND meat in the control were lower than those of the freezing and thawing groups (P<0.01, P<0.05), but shear force (SF) of the control was higher than that of other groups (P<0.01). Moisture content of the ST group was higher than that of the FT group (P<0.05), and protein content of the FF group was higher than that of control (P<0.05). Stearic acid (C18:0) of the SF group was higher than that of the FF group (P<0.05). Arachidonic acid (C20:4n6) of control was higher than that of the SF and ST groups (P<0.01, P<0.05). Alanine, aspartic acid, glutamic acid, serine, and tyrosine content of the control were lower than that of the freezing and thawing groups (P<0.05). These results show that freezing and thawing methods affect meat color, shear force, cooking loss, and WHC-related water content.

• The Journal of the Convergence on Culture Technology
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• v.6 no.2
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• pp.99-106
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• 2020

Changam, Lee Samman(1770~1845), who created his own handwriiting to be referred to as the three great writers of the late Joseon Dynasty, invented as the original 'Haengunyusu Typeface' and developed Calligraphy spirit of DonggugJinche in Honam province. He ultimately pursued the state of tonglyeong by raising the personality of 'writing is the person's personality' and the attitude of learning the old. Through the book chang-amseogyeol, he basically polished Haeseo of Han Dynasty and Wi Dynasty and emphasized that Haengseo and Choseo are done automatically when muscle strength and bone strength are established. And since calligraphy originated from 'nature', it goes through the 'Beobcheongwijin' spirit. After doing so, expressed the state of tonglyeong of " mubeob-ibeob ", the stage of reaching. In addition, Changam showed the aesthetic that you can get the novelty by pursuing the philosophy of 'Wu' and the 'beauty of Stupid and Lacking' based on LaoTzu and ChuangTzu. This is a philosophy that follows nature's logic to reveal nature's nature. And it is an aesthetic that protects his 'True Wu' without knowing and greedy. On the other hand, Changam promoted natural and vital beauty through force in the method of using the brush. He suggested the 'Push and Hard' of the Han dynasty, pushing it with force using this power properly. In particular, the feeling of an IlunMujeog brush in 『Changam Calligraphy-The cloud stays Poem』 overflows with the vitality and bizarre and strange dynamism of the spirit and typeface as eum-yang harmonizes with each other. In addition, the beauty of Push and Hard containing polyeoghamse is misaligned, but it has achieved a natural aesthetic without invading. This work demonstrates the real look of Changam choseo. In addition, the beauty of Push and Hard containing polyeoghamse is misaligned, but it has achieved a natural aesthetic without invading. Changam proves the real look of "Haedong's best Chose Maestro".

• Journal of Animal Science and Technology
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• v.46 no.5
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• pp.821-832
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• 2004

A total of 80 pigs were used to investigate the effect of dietary glycine betaine(N,N,N-trimethylglycine) on pork quality during cold storage. About 70 kg pigs were randomly a1loted into one of four experimental diet groups(0%, 0.2%, 0.4% and 0.6% glycine betaine). Pigs were slaughtered at approximately 110 kg live weight, and pH, color(CIE $L^* a^* b^*$), shear force, sarcomere length, lipid oxidation and composition of fatty acid were measured in pork loin for 13 days of cold storage. The concentration of glycine betaine in pork loin was significantly increased(P<0.05) with increasing of glycine betaine level in diet. Pork loins from dietary betaine groups showed significantly higher muscle pH and lower CIE $b^*$ values compared to control group after 13 days of storage. There were significant differences in shear force values among pork loins from diet groups at 24 hrs postmortem. However, pork loins from control diet showed longer sarcomere length than those of dietary betaine groups. Dietary glycine betaine increased the ratio of saturated fatty acids and decreased unsaturated fatty acids in pork loins. Especially the ratios of linoleic and myristic acid were decreased with increasing dietary betaine level. However, dietary glycine betaine did not affect lipid oxidation (TSARS) and sensory evaluation during cold storage.

• Food Science of Animal Resources
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• v.27 no.4
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• pp.409-415
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• 2007

This experiment was conducted to investigate the effects of dietary enzyme mixture fortified with ${\beta}-glucanase$ on the growth performance, serum components and meat quality of broiler chicks. 31,800 Ross 208 male broiler chicks were randomly allotted into 2 groups, the control and 0.3% enzyme diet with ${\beta}-glucanase$ supplementation groups. Control group chicks were fed the control (corn-soybean meal based) diet and the treatment group chicks were fed the 0.3% enzyme mixture supplemented with ${\beta}-glucanase$. The growth performance, serum components and meat qualities such as pH, color, water holding capacity, cooking loss, and shearing force of meats were investigated. The results showed that the growth performance of chicks fed the 0.3% enzyme mixture diet were improved compared to that of the control group, as much as 5% in growth rate, 19% in average weight, 6.8% in performance index, and 5.5% in feed efficiency. Although, there were no significant differences in the muscle color degrees ($L^*a^*b^*$) and shearing force between the control group and experimental group, the water holding capacity and cooking loss of the experimental group were significantly higher than those of control group (p<0.05). The antibody titers in serum against the antigens of Newcastle disease and Infectious Bursal disease were higher in the experimental group than in the control group. Altogether, these suggest that the broiler diet containing 0.3% enzyme mixture fortified with ${\beta}-glucanase$ activity can improve the growth performance, immune reaction, and meat quality of broiler chicks.

• Food Science of Animal Resources
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• v.28 no.4
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• pp.480-485
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• 2008

In this experiment, 5 treatments consisted of control, probiotics (0.2%; T1), illite (1.0%; T2), activated carbon (1.0%; T3), and hardwood vinegar (1.0%; T4) as diets of chicken were evaluated for 35 days through feeding of 200 male chickens (Arbor Acre Broiler). Thigh muscle from slaughtered chickens were analyzed on pH, volatile basic nitrogen (VBN), thiobarbituric acid reactive substance (TBARS), shear force, and meat color during 10 d of cold storage at $4{\pm}1^{\circ}C$. Groups of T3 and T4 showed higher pH levels compared to the control group, and T4 showed significantly higher value. Over the storage period, all treatment groups showed increase in pH (p<0.05). Values of VBN of T1, T3, and T4 were lower than those of the control group and T2 up to 7 d of storage (p<0.05), but there was no significance at 10 d of storage. Values of TBARS of T3 and T4 were lower than the control group, T1, and T2, while all treated groups showed rapid increase of TBARS values over storage period (p<0.05). Shear force did not show significant difference among treated groups, but it was decreased over storage. Lightness of meat color (L) in treated groups was higher than the control, and T4 showed the highest value during entire storage period (p<0.05). Yellowness levels (b) of T3 and T4 were higher than the control group. These results may suggest the improvement of chicken meat quality and shelf life via the addition 1% activated carbon and 1% hardwood vinegar into feed.

• Korean Journal of Poultry Science
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• v.48 no.1
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• pp.13-22
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• 2021

The present experiment was conducted to evaluate the effect of stocking density on the growth performance, immune status, and meat quality of broilers. In total, 385 one-day-old Ross 308 broilers were randomly assigned to one of four distinct stocking densities: 26 birds/㎡, 22 birds/㎡, 19 birds/㎡, and 16 birds/㎡. They were fed the diet ad libitum for 5 weeks. Immunoglobulin (Ig) and corticosterone levels were evaluated, and growth performance, blood parameters, and breast meat quality were determined. It was observed that the weight gain and feed intake of growers (21~35 d) and broilers (0~35 d) were significantly reduced as the stocking density increased (P<0.05). However, the feed intake of starters (0~21 d) significantly increased as the stocking density increased (P<0.05). There were no significant differences in the biochemical profiles among the four different stock densities. Furthermore, no significant differences were observed in the stress parameters: (heterophils / lymphocytes ratio and corticosterone), IgA, and IgM; however, IgG significantly increased with stocking density (P<0.05). The pH, water holding capacity, and cooking loss of the muscle were all unaffected by the stocking density, but the shear force (tenderness) increased slightly as the density increased. The findings of this study suggest that a lower stocking density (16 birds/㎡) significantly improved the shear force of breast meat and IgG in broilers.

• Journal of Animal Science and Technology
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• v.46 no.3
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• pp.427-436
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• 2004

The current study was conducted to determine the effect of suspension method on satisfaction level of Korean consumers and objective meat quality traits in Hanwoo longissimus dorsi(LD), triceps brachii(TB) and semimembranosus(SM) muscles. Eighteen Hanwoo steers were slaughtered and alternative sides were hung either by pelvic bone(TS) or Achilles tendon(Al). Sensory characteristics, WB-shear force, sarcomere length, water-holding capacity, saroomere length and cooking loss were determined after a 7-d chiller ageing. Higher carcass quality grade received significantly(p < 0.05) greater eating quality for LD, but the grade did not affect eating quality for both TB and SM. TS did not influence objective and subjective meat quality for TB, but that significantly(P < 0.05) improved eating quality for LD and SM. The most noticeable result was that when SM was tenderstretehed, eating quality was equivalent to that of nonna1ly hung LD. In relationship between objective and subjective meat quality assessments, eating qualty for LD had a significant(P < 0.05) relationship with intramuscular fat content, while that for SM was greatly(P < 0.05) related to saroomere length. The current study indicated that pelvic hanging was an effective way to improve eating quality both LD and SM, and carcass quality grades did not greatly reflect eating quality of SM and TB. The data also implied that instnunental measurements poorly estimated the satisfaction level of Korean conswners.

• Journal of Animal Science and Technology
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• v.44 no.3
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• pp.315-326
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• 2002

This study was conducted to examine the effects of Red clay(Hwangto) as feed additives with 26 Hanwoo steers at two regions for 540 days from six to 24 months of age on feed efficiency, meat quantity and meat quality. Feeding trial 1 was conducted with two treatment groups by five heads/treatment which were T1(Control) and T2(Control+ad libitum Hwangto) at National Livestock Research Institute. Feeding trial 2 was conducted with four treatment groups by four heads/treatment which were T1(Control), T2(Control+2% Hwangto), T3(Control+5% Hwangto) and T4(Control+ad libitum Hwangto) at a private Hanwoo breeding farm. In feeding trial 1, average daily gains by growing, fattening, finishing and over-all periods were 0.572, 0.866, 0.869 and 0.769kg in T1, and 0.537, 0.904, 0.857 and 0.766kg in T2, respectively. Average daily gain for growing and finishing period was high in T1 but in T2 for fattening period, which were not statistically significant. Also concentrates and TDN intakes per kg gains were not statistically significant by treatments. In carcass characteristic, dressed carcass and red meat percentage were high in T1 but in T2 for retailed cut percentage without significant difference. The yield index and shear force was 69 and 70, 4.4 and 6.1 kg/$cm^2$ in T1 and T2, respectively. In palatability traits, the panel test scores of juiciness, tenderness and flavor were 4.08 and 4.64, 3.42 and 3.96, 4.58 and 4.80 in T1 and T2, respectively. which showed a tendency to improvement in Hwangto feeding groups. In feeding trial 2, the range of average daily gains were 0.656(T6) to 0.772(T3), 0.937(T6) to 1.009(T5), 0.592(T3) to 0.675kg(T6) in growing, fattening and finishing period, respectively. Although it was high in T3, T5 and T6 at growing, fattening and finishing period, respectively, it was not significantly different by treatments. The ranges of concentrates and TDN intakes per kg gains were 8.71 to 9.50(average 9.05) and 7.52 to 7.64kg(average 7.55kg), they all were lower in Hwangto feeding groups than in control about 4.5 to 8.3% and 1.2 to 1.6%, respectively. In carcass characteristics, back-fat thickness, loin eye muscle area and yield index were not difference by treatments, but marbling scores were high in T5 and T6 than in percent. Summarizing above results, it may be concluded that the use of unprocessed Hwangto as feed additives for growing-fattening steers seems to improve meat quality but not red meat quantity and feed efficiency, and may be required to feed ad libitum during the finishing period.

• The Korean Journal of Physiology
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• v.9 no.1
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• pp.13-22
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• 1975

From the study of movements of $Ca^{++}$ in frog cardiac muscle, Niedergerke (1963) postulated that $Ca^{++}$ necessary for the cardiac contraction is stored in a specific pool. Langer et al (1967) and DeCaro (1967) also found a close relationship between the change of $Ca^{++}$ flux kinetics and the change of contractile force. According to the studies of several investigators, Ca II (Bailey and Dressel 1968) or phase I and II (Langer 1965, Langer et al 1967, 1971) in the $Ca^{++}$ washout curve was associated with cardiac contractility. This investigation was aimed to elucidate the anatomical region of the contractile active $Ca^{++}$ pool. At the same time, it was assumed in this study that $Ca^{++}$ in the sarcoplasmic reticulumn represents one of the major intracellular $Ca^{++}$ pool and cardiac contractility was also dependent on the intracellular $Ca^{++}$ concentration. Consequently, this experiment was performed at different temperatures to activate to activate inhibit the deactivating process of activated $Ca^{++}$ in the intracellular space to see if changes in the contractility decay curve existed at different temperatures. The isolated hearts of rabbits and turtles (Amyda maackii) were attached to the perfusion apparatus according to the method employed by Bailey and Dressel (1968). The isolated hearts were initally perfused with a full Ringer solution containing 2 mg/ml of inulin for 1 hr, and then $Ca^{++}$ and inulin-free Ringer solution was perfused while the isometric tension was recorded and a serial sample of perfusion fluid dripping from the cardiac apex was collected for 10 sec throughout experimental period. The above procedure was performed at $23^{\circ}C$, $30^{\circ}C$ and $38^{\circ}C$ on the rabbit heart and $10{\sim}13^{\circ}C$, $10^{\circ}C$, $25^{\circ}C$, $30^{\circ}C$ and $35^{\circ}C$ on the turtle heart. After determination of $Ca^{++}$ and inulin concentration of the samples, the $Ca^{++}$, inulin washout curve and the contractile tensin decay curve were analysed according to the method of Riggs (1963). The results were summarized as follows; 1. In the rabbit heart, there are 2 inulin compartments, 3 $Ca^{++}$ compartments and sing1e exponential decay of contractile tension. In the turtle heart, there are $1{\sim}2$ inulin compartments, $1{\sim}2$ $Ca^{++}$ compartments and $1{\sim}2$ phases of contractile tension decay. The fact that the inulin space was divided into 3 compartments in the washout curve in these hearts indicates the presence of heterogeneity in cardiac perfusion, i.e., overfused and underperfused area. 2. Ca I a9d Ca II in these hearts were found to have $Ca^{++}$ in the ECF compartments because their half times in the washout curves were far smaller than those of the inulin washout curves in the rabbit heart and similar to those of the inulin washout curves in the turtle heart. Ca III in the rabbit heart may have originated from the intracellular $Ca^{++}$ store. But no Ca III in the turtle heart was found. This may be due to the fact that the iutracellular $Ca^{++}$ pool in the turtle heart was too small to detect using this experimental procedure since sarcoplasmic reticulumn in the turtle heart is poorly developed. 3. In the rabbit heart, there were no chages in the half time of Ca I, Ca II, inulin I and inulin II at different temperatures, but the half time of Ca III was significantly prolonged at lower temperatures, and the half time of the contractile tension decay tended to be prolonged at lower temperatures but this was not significant. In the turtle heart, there were no changes in the half time of Ca I, Ca II, inulin 1, inulin II and phase I of the contractile tension decay at different temperatures, but the half time of phase II of the contractile tension decay was significantly prolonged at lower temperatures. This finding indicates that intracellu!ar $Ca^{++}$ in these hearts was also responsible particulary for maintaining the cardiac contractility at the lower temperatures. 4. The half times of contractile tension decay were shorter than those of Ca II in the $Ca^{++}$ washout curves in both animal hearts. According to the above results it was shown that $Ca^{++}$ in ECF is primarily and $Ca^{++}$ in the intracellular space is partially associated with the cardic contractility.

• The Korean Journal of Physiology
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• v.22 no.2
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• pp.189-206
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• 1988

The effects of ouabain on the contractile and electrical activities were investigated in the isolated preparations of guinea-pig taenia coli, and compared with those of vanadate. Spontaneous contractions were recorded with force transducer, and electrical activites were measured by use of suction electrode, or single sucrose-gap technique. The contractions were induced by the electrical stimulation for 5 seconds every 1 minute with alternating current (60 Hz, 3.0 V/cm) through the platinum electrodes located in parallel with the long axis of the preparation. All experiments were performed in tris-buffered Tyrode solution which was aerated with $100%{\;}O_2$ and kept at $35^{\circ}C$. The results obtained were as follows: 1) Responses of spontaneous contractions to ouabain were concentration-dependent; $10^{-7}M$ ouabain caused a rise of basal tone. Above the concentration of $10^{-6}M$ ouabain, an initial increase followed by a decrease in tension was observed. 2) A continuous spike discharge was induced by the administration of $10^{-7}M$ ouabain. Above $10^{-6}M$ ouabain, a transient initial increase followed by a decrease in spike frequency and amplitude was produced, and finally membrane potential was sustained at a certain level without a spike discharge. 3) The characteristic response to $10^{-7}M$ ouabain was not blocked by the pretreatment with $10^{-7}M$ atropine. 4) The electrically induced contractions were completely suppressed at the concentration of $2{\times}10^{-7}M$ ouabain. These contractions were blocked more rapidly in paralled with the increase in ouabain concentration. 5) Effects of vanadate on the spontaneous activities were quite different from those of ouabain; $10^{-6}M$ vanadate increased the amplitude of contractions and $10^{-5}M$ vanadate increased slightly both amplitude and frequency of spontaneous contractions. $10^{-4}M$ vanadate showed irregular phasic contractions superimposed on the increased basal tone. 6) $10^{-5}M$ vanadate depolarized the membrane potential and shortened the interval between the bursts of spike discharge, whereas $10^{-4}M$ vanadate induced continuous spike discharge with membrane depolarization. 7) Vanadate caused a characteristic inhibitory response to the contractions induced by electrical stimulation; An initial rapid inhibition of tension development and then gradual recovery to a certain level. From the above results, the following conclusions could be made: 1) The rise of basal tone at $10^{-7}M$ ouabain is due to continuous spike discharge without a silent period. The continuous spike discharge is likely to be associated with a slight membrane depolarization caused by the blockage of Na pump. 2) The biphasic response induced by above $10^{-6}M$ ouabain seems to occur by the different mechanisms. The initial increase in tension is associated with depolarization along with an increase in spike frquency, whereas the subsequent relaxation occurs through a non-electrical mechanism. 3) The characteristic response to $10^{-7}M$ ouabain is resulted not from the action on intrinsic nerve terminal, but from its direct action on the membrane of smooth muscle cells. 4) The phasic contractions superimposed on the increased basal tone at the concentration of $10^{-4}M$ vanadate is resulted from the continuous spike discharge with membrane depolarization, of which mechanism remains unknown. 5) The inhibitory action of ouabain on the electrically induced contractions suggests that the increasein intracellular Na in some way inhibits the electrically induced $Ca^{2+}$ influx. The mechanism of vanadate action on the induced contractions remains unknown.