• Journal of Food Hygiene and Safety
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• v.39 no.1
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• pp.54-60
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• 2024

This study investigated the effectiveness of using pathogens and aqueous acids to reduce the Aspergillus ochraceus and Rhodotorula mucilaginosa contamination in livestock production environments. For this study, 1 mL of each bacterial suspension (10⁷-10⁸ spores/mL) was inoculated on a knife surface, dried at 37℃, and used under each treatment condition. First, to investigate the effect of organic acids, acetic, lactic, and citric acids were used. Subsequently, to select the appropriate concentration, they were prepared at concentrations of 0.5, 1, 2, 3, 4, and 5%, respectively. Accordingly, to further maximize the effect of organic acid treatment, we combined the treatment with ultraviolet light. The two strains showed a significant difference (P<0.05) compared to the initial strain, with a greater than 90% decrease in the concentrations of all organic acids. Consequently, acetic and lactic acids decreased by approximately 5 and 2 log colony forming unit (CFU)/cm², respectively, when treated with ultraviolet light (360 mJ/cm²); however, citric acid decreased by less than 1 log CFU/cm². However, when manufactured with 4% acetic acid, a severe malodor was emitted, making it difficult for workers to use it in a production environment. Accordingly, the optimal treatment conditions for organic acid and ultraviolet light for application were selected as follows: immersion in a 4% lactic acid solution for 1 minute and then, sterilization with ultraviolet light at 360 mJ/cm². Finally, when a pork meat sample was cut with a knife that was finally washed with lactic acid and treated with ultraviolet light, the low level of inoculum transferred from the cleaned knife to the surface of the sample was not detected. In conclusion, using this established method can prevent cross-contamination of the surface of the meat during processing.

• Journal of Food Hygiene and Safety
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• v.13 no.4
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• pp.430-440
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• 1998

The average number of total viable counts for the commercial pork tested was 19/g, coliform 1.8/g, psychrophilic bacteria 15/g, heterotrophic bacteria 12/g, fecal streptococcus 6.2/100 g, Pseudomonas aeruginosa 13/100 g and none of heat-resistant bacteria and Staphylococcus was detected. That for the commercial beef tested was 130/g, coliform 5.2/g, psychrophile 140/g, heterotroph 28/g, Staphylococcus 1.2/g, fecal streptococcus 9.5/100 g, Pseud. aeruginosa 1.9/100 g and heat-resistant bacteria was not detected. That for the commercial chicken tested was 8800/g, coliform 53/g, psychrophile 4600/g, heterotroph 4700/g, fecal streptococcus 9.9/100 g, Pseudo aeruginosa 2.5/100 g. That for milk was 4700/ml, psychrophile 120/ml, heterotroph 420/ml and the others were not detected. That for the commercial cheese was 3.2/g, psychrophile 2.3/g, heterotroph 1.6/g, Staphylococcus l/g, fecal streptococcus 9.1/g. That for fermented milk was $10^{7}/ml$, heatresistant bacteria $10^{6}/ml$, fecal streptococcus 2400/100 ml, lactobacillus $3.2{\times}10^{15}/ml$, in accordance with lactic acid bacteria and the others were not detected. There was not detected any indicator organisms from ham, sausage, butter, eggs and quails in the commercial fooods tested. SPC, coliform, psychrophile and heterotroph in commercial meats stored at $10^{\circ}C$ were increased rapidly as time goes on but heat-resistant bacteria, staphylococcus, fecal streptococcus and Pseudo aeruginosa were constant. At $20^{\circ}C$, SPC, coliform, psychrophile, heterotroph and fecal streptococcus were the highest at 7 days and heat-resistant bacteria, staphylococcus and Pseudo aeruginosa were increased a little. At $30^{\circ}C$, all indicators were increased rapidly for 3 and 7 days and then decreased rapidly. All indicator organisms were increased at the level of 10/g for 14 days in meat products stored at $10^{\circ}C$, but SPC, psychrophile and heterotroph in meat products stored at $20^{\circ}C$ were increased at the level of $lO^5/g$. It showed that the indicators in meat products stored at $30^{\circ}C$ had a tendency to increase at the level of $10^{2}/g$ relative to those stored at $20^{\circ}C$. SPC, psychrophile and heterotroph in milk stored at $10^{\circ}C$ increased up to the level of $10^4/ml$, but coliform, staphylococcus, fecal streptococcus and Pseudo aeruginosa were not detected. As stored at $20^{\circ}C$ and $30^{\circ}C$, they were increased rapidly for 1 or 3 days and then constant for a long time.

• Korean Journal of Agricultural Science
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• v.8 no.1
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• pp.51-63
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• 1981

The results of a crossbreeding experiment with a total of 315 litters and 325 pigs of Berkshires, Hampshires, Durocs, Landraces, Large Whites, eight different two-breed crosses and twelve different three-breed crosses, produced at Livestock Experiment Station from 1975 through 1979, are summarized as follows. 1. Number born alive per litter was largest in the D♂${\times}$(Lw♂${\times}$L♀) $F_1$ ♀ mating, followed by the D♂${\times}$(H♂${\times}$L♀) $F_1$ mating, and smallest in the Hampshires. The pigs in the 3rd-6th parities had larger litter size at birth than those in other parities. 2. Birth weight of pig was heaviest in L♂${\times}$Lw♀ mating and lightest in the Large White. The total litter weight at birth was heaviest in the D♂${\times}$(Lw♂${\times}$L♀) $F_1$ ♀ mating, followed by D♂${\times}$(H♂${\times}$L♀) $F_1$ ♀ and Lw♂${\times}$L♀ matings, and was smaller in Hampshires and Birkshires. 3. Litter size at weaning was largest in the D♂${\times}$(Lw♂${\times}$L♀) $F_1$ ♀ mating, followed by D♂${\times}$(H♂${\times}$L♀) $F_1$ ♀ and Lw♂${\times}$L♀ matings, and was smaller in Durocs and Hampshires. The pigs in the 3rd-6th parities had larger litter size at weaning than those in other parities. 4. The total litter weight at weaning was heaviest in the D♂${\times}$(Lw♂${\times}$L♀) $F_1$ ♀ mating, followed by H♂${\times}$(Lw♂${\times}$L♀) $F_1$♀ and Lw♂${\times}$L♀ matings, and was lighter in Durocs and Hampshires. The weaning weight of pig was largest in D♂${\times}$(Lw♂${\times}$L♀) $F_1$ ♀ mating and lightest in L♂${\times}$H♀ mating. 5. Survival rate at weaning was highest in L♂${\times}$Lw♀ mating, followed by D♂${\times}$(L♂${\times}$H♀) $F_1$ ♀ and D♂${\times}$(H♂${\times}$L♀) $F_1$ ♀ mating, and was lowest in Durocs. 6. The three-breed cross from D♂${\times}$(H♂${\times}$L♀) $F_1$ ♀ mating had the highest average gain and lowest feed requirement per unit gain, followed by the D♂${\times}$(Lw♂${\times}$L♀) $F_1$ ♀ and H♂${\times}$(Lw♂${\times}$L♀) $F_1$ ♀ matings. The Birkshires and Landraces ranked lowest among the 25 mating groups compared for both of the traits. Males had higher average daily gain than females by about 0.06kg and had lower feed requirement by about 0.14. 7. The three-breed crosses from D♂${\times}$(H♂${\times}$L♀) $F_1$ ♀, D♂${\times}$(Lw♂${\times}$L♀) $F_1$ ♀ and H♂${\times}$(Lw♂${\times}$L♀) $F_1$ ♀ matings reached 90kg body weight at younger age than the other groups. The D♂${\times}$(H♂${\times}$L♀) $F_1$ ♀ group reached 90kg at younger age than the Landrace by 39 days. 8. The dressing percentage and lean meat percentage tended to be higher in H♂${\times}$(Lw♂${\times}$L♀) $F_1$ ♀, H♂${\times}$L♀ and L♂${\times}$B♀ matings compared to the other mating groups. The loin-eye area was largest in the Lw♂${\times}$L♀ mating and smallest in the B♂${\times}$L♀ mating. Males had higher dressing percentage, higher lean meat percentage and lion-eye area than females. The backfat was thinnest in purebred Hampshire and was thickest in B♂${\times}$L♀ mating. 9. The results obtained in this study suggest that the two-breed cross from Lw♂${\times}$L♀ mating, and the three-breed crosses from D♂${\times}$(Lw♂${\times}$L-♀) $F_1$ ♀ and D♂${\times}$(H♂${\times}$L♀) $F_1$♀ matings are superior crossbreds for reproductive and pork prodnction performance.

• Journal of Animal Science and Technology
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• v.51 no.3
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• pp.185-192
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• 2009

Fatty acid synthase (FASN) is a multi-functional enzyme with a central role in the synthesis of long-chain fatty acid and has been considered as a positional candidate gene for BTA 19 quantitative trait loci (QTL) affecting milk-fat content and fatty acid composition. In this study, we sequenced the FASN gene in several cattle breeds including Hanwoo and imported beef cattle, and identified novel DNA polymorphisms and their linkage relationship in Hanwoo. We found a significant frequency difference of the FASN (AF285607) g.17924 A$\rightarrow$G polymorphism between Hanwoo (70%) and other breeds and this polymorphism has been known for an association with fatty acid composition in Angus. Furthermore, by direct DNA sequencing in 18 unrelated Hanwoo, we identified 27 SNPs including nine novel variations in the FASN gene. Among 27 SNPs identified in the FASN gene, four SNPs were further genotyped in 100 Hanwoo and 96 imported beef cattle, and analyzed for haplotype construction and association with beef quality traits. We performed haplotype block and linkage disequilibrium studies using four selected SNPs. Two different haplotype blocks (block A: g.10568 C$\rightarrow$T and g.11280 G$\rightarrow$ A; block B: g.13125 C$\rightarrow$T and g.17924 G$\rightarrow$A) were constructed and the block A in particular had a very high r2 (0.936), which indicated a nearly complete linkage disequilibrium existed between the g.10568 C$\rightarrow$T and g.11280 G$\rightarrow$A polymorphisms. A total of four major haplotypes (frequency > 0.05) were identified with the four polymorphisms including TATG (0.36), CGCG (0.31), CGTA (0.19) and TACG (0.06). Statistical association analysis revealed that the g.10568 C$\rightarrow$T and g.11280 G$\rightarrow$A polymorphisms in the FASN were significantly associated with meat color (P=0.004) and texture (P=0.0114). The g.13125 C$\rightarrow$T and g.17924 G$\rightarrow$A polymorphisms in the FASN were also significantly associated with back-fat thickness and quantity index (P=0.0179 and 0.0495, respectively). Our findings suggested that the FASN gene polymorphisms may be used for determining the (unsaturated) fatty acid contents and carcass trait in the Hanwoo beef.

• The Korean Journal of Food And Nutrition
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• v.11 no.1
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• pp.11-19
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• 1998

This study was performed to investigate the information of food preference of workers for meal served by industry foodservice. The subjects were composed of 212 office workers and 220 laborers. The results were obtained as follows : 50.7% of the subjects were 30∼39 years old ; 72.0% of them had high school education ; the type of favored food was Korean style cooked rice ; food taste was the most important point in food selection. Preference form main foods : Cooked rice was preferred the most by the subjects. Both office workers and laborers liked Kalkooksoo and vegetable bread and cooked rice covered with beef was preferred by office workers and cooked rice covered with raw fish pieces was preferred by laborers. Also they disliked Hash rice, Curry rice and rice-cake soup in the pattern. Preference for side-dish : The Acceptances for side-dishes were high in soybean paste soup(office workers : 37.5%, laborers : 31.5%), hot chowder of corvina(26.1%, 25.7%), kimchi stew(30.5%, 28.8%), beef broiled in soy(32.5%, 30.5%), baked fish(32.5%, 31.9%), pachon(20.7%, 25.9%), a meat inside a razor clam(25.1$, 29.2%) and Chinese cabbage kimchi(44.5%, 46.3%), in that order by both of them. But in office workers, seasoned bean sprouts and steamed beef-rib were shown to have high preference and in laborers seasoned spinach and steamed pork-rib were high. Preference of snacks : The preferences for snacks were high in milk(office workers : 50.3%, laborers : 48.5%), Songpean(28.9%, 30.1%), coffee(30.8%, 32.5%), Sikhye(18.8%, 17.5%), in that order by two groups.

• Journal of Animal Science and Technology
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• v.49 no.1
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• pp.9-14
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• 2007

Data of 369 commercial pigs produced from YorkshrexLancrace (YL F1) sows crossed with either Duroc (D), Berkshire (B) or BerkshirexDuroc(BD F1) as a terminal sire were used for the comparison of carcass garde and real retail cut yield. The crosses were performed between May, 2004 and May, 2006 at three interrlated farms belonging to the Gyeongam pork brand. The average carcass weight, carcass backfat thickness, carcass rate, AB grade ratio, lean meat yield were 84.78±0.33kg, 20.72±0.237mm, 76.25±0.208%, 85.7% and 44.30±0.158%, respectively. The average weights of real retail cut were 10.32±0.062kg belly, 4.17±0.025kg boston butt, 3.88±0.022kg rib, 8.40±0.040kg picnic, 15.15±0.081kg ham, 6.44±0.043kg loin and 0.94±0.006kg tender loin. In comparisons of carcass traits among cross types, carcass weights and backfat thicknesses of YL(♀)×B(♂), YL(♀)×BD(♂) and YL(♀)×D(♂) were 85.73±0.516kg, 82.69±0.788kg and 84.79±0.603kg, respectively and 22.09±0.356mm, 20.33±0.543mm and 19.58±0.415mm, respectively. The YL(♀)×B(♂) cross showed the highest carcass weight and backfat thickness. The ratio of AB grade were 0.83±0.030% in YL(♀)×B(♂), 0.97±0.046% in YL(♀)×BD(♂) and 0.83±0.035% in YL(♀)×D(♂), and the YL(♀)×BD(♂) was higher than other two crosses. Weights of belly were 10.28±0.092kg in YL(♀)×B(♂), 10.59±0.133kg in YL(♀)×BD(♂) and 10.25±0.107kg in YL(♀)×D(♂). Consequently, the YL(♀)×BD(♂) cross showed the highest yield. In conclusion, there was no difference in carcass yield of commercial pigs derived from BD (F1) terminal sires with those from D terminal sires. However, weight of belly and AB grade ratio from BD (F1) terminal sires are higher than two others. Therefore, BD (F1) sire could be utilized as terminal one and contribute better profit for the pig industry.

• Journal of Food Hygiene and Safety
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• v.23 no.3
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• pp.248-256
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• 2008

To investigate the epidemiological characteristics of 68 Listeria monocytogenes isolates, including 11 reference strains and 57 isolates from imported US beef, domestic meats(beef, pork, chicken meat), raw milk, and milk plants. L. monocytogenes was to evaluate the production of virulence proteins, such as hemolysin(LLO) and lecithinase(LCP), the adsorption of Congo red(CRA), and to detect virulence genes using the polymerase chain reaction(PCR). In the study of virulence protein production, 68(100%), 62(91.2%), and 54(79.4%) of the 68 L. monocytogenes strains were positive for LLO production, the LCP test, and the CRA test, respectively, while strains of other species, such as L. innocua, L. gray, L. murrayi, and L. welshimeri, were not. There were no significant differences between L. monocytogenes serotypes and the ability to produce LLO or LCP. L. monocytogenesstrains had very high hemolytic titers(2 to 16 fold), while the other Listeria species, other than L. ivanovii and L. seeligeri, did not. The hemolysin activities of L. monocytogenes, L. ivanovii, and L. seeligeri usually exceeded 1.0 HU/mg, while those of other Listeria spp. were less than 0.04 HU/mg. In the PCR assay, all of the L. monocytogenes strains contained the hlyA, plcA, plcB, inlA, and inlB virulence genes and produced a product of the expected size. In the PCR of the actA gene, the expected 385-bp product was seen in 39(57.4%) L. monocytogenesstrains, while an unexpected 268-bp product was seen in 29(42.6%) strains. Most L. monocytogenes strains isolated from Hanwoo beef produced the 385-bp actA gene product, while strains of imported US beef usually produced the 268-bp actA gene product. By contrast, no virulence gene products were amplified in the other Listeria spp.

• Journal of Animal Science and Technology
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• v.45 no.2
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• pp.219-228
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• 2003

Two experiments were conducted to investigate the influence of dietary supplementation of yeast culture on the nutrient digestibility, performance and meat quality in growing-finishing pigs. Corn-soy basal diets contained 20, 18, and 16% CP and 3,265kcal/kg ME at different growth stages. One hundred and twenty pigs(8wk-old) were allocated into four supplementation levels of yest culture (0, 0.1, 0.2, 0.4%) in Expt 1. Weight gain, feed intake and feed efficiency were periodically recorded for 112 days. A metabolic feeding trial was conducted to measure the nutrient digestibility. Physical and chemical characteristics of the Longissimus Dorsi muscle(LM) from the pigs were measured at the end of experiment (Expt 2). In Expt 1, weight gain and feed efficiency were not different among the dietary treatment groups during the overall period. The digestibilities of protein and fiber were greater in 0.1% and 0.2% yeast culture-supplemented groups than in control (P<0.05). However, fat and ash digestibilities were not improved by the dietary treatment. In Expt 2, the LM protein content in 0.1% yeast culture-supplemented group, but not in 0.2% or 0.4%-supplemented group, was greater than that in the control group (P<0.05). The LM pH, purge loss, cooking loss and color were not affected by the dietary treatment. The LM shearing force was less in 0.2% yeast culture-supplemented group than in the control group (P<0.05). Other LM physicochemical properties did not differ between the dietary treatment groups. Total saturated and unsaturated fatty acids percentages and total cholesterol content of the LM did not differ across the dietary treatment groups.

• Food Science of Animal Resources
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• v.25 no.4
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• pp.391-396
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• 2005

The objective of this study was carried out investigate the changes of carcass characteristics, physico-chemical characteristics and fatty acid composition in crossbred pigs (Korean native breed ${\times}$ Landrace breed) by backfat thickness. A total 182 Pigs were divided into 3 groups by there backfat thickness, i.e., <11.80mm, $11.80\~25.01mm\;and\;25.01mm<.$ The live weight carcass weight and dressing percent of backfat thickness 25.01mm< group were higher compared to those for backfat thickness <11,80mm and $11.80\~25.01mm group, but the final grade were lower. The pH of backfat thickness 25.01mm< group were higher compared to those for backfat thickness <11.80mm and $11.80\~25.01mm$ group. Shear lone of 25.01 mm< group were lower than that of other groups. Water, crude fat content and cooking loss have no difference between the 3 groups. The hardness of backfat thickness 25.01mm< group were higher compared to those for backfat thickness <11.80mm and $11.80\~25.01mm$ group. The yellowness $(b^*)$ of meat and fat color in backfat thickness 25.01mm< group were lower compared to those for backfat thickness <11.80mm and $11.80\~25.01mm$ group. The stearic acid and saturated fatty acid content were higher compared to those for backfat thickness <11.80mm and $11.80\~25.01mm$ group but the linoleic acid and unsaturated fatty acid content were lower.

• Journal of Nutrition and Health
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• v.41 no.1
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• pp.77-88
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• 2008

This research was carried out a to investigate the food habit and preference of parents' social and economic level with 681 children (145 of Kindergarten, 300 of Children, 236 of Adolescences) in Seoul and Gyeonggi area using question naires. The parents' income level divided into 2 groups, less than 4 million won and equal or greater than 4 million won. Most of the middle years were over-weighing but kindergarten and adolescences had standard weights. The majority of parents had Bachelor degrees, most of father were office workers, majority of mothers of kindergarten with parents' income level less than 4 million won were professional women and mothers of the rest of the groups were mostly house wives. The middle years with parents income level less than 4 million son were skipping meals most frequently, but other groups didn't show much differences in their eating habits. All age groups showed that they like meats the most and dislike vegetables the worst. All age groups also showed that they mostly eat out 1-2 times a week and the next was 3-4 times a week. All age groups preferred ice creams, fruits, juices and snacks for their desserts. The middle years with parents' income equal or greater than 4 million won also showed high preference on strawberry and chocolate flavored milk, burgers and pizzas. The food s that preferred to eat when dining out were Chinese foods (Ja-jang-myeon and sweet and sour pork) for kindergarten group, Korean foods (kalbi and bulgogi) for the middle years with parents' income level less than 4 million won, family restaurant food (steak and rib) for the middle years with parents' income level equal or greater than 4 million won and Korean foods (kalbi and bulgogi) for the adolescences. The preferred cooking methods were roast (fish and sea weeds) for the kindergarten, roasted meat for the middle years, Kimchi and bean paste pot stew for the adolescences with parents' income level less than 4 million won and roasted meats for the adolescences with parents' income level equal or greater than 4 million won. The results showed that the adolescences with higher parental income lever preferred meats.