• Journal of Life Science
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• v.23 no.12
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• pp.1477-1485
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• 2013

The aim of this study was to evaluate changes in the meat quality and natural di-peptide (carnosine and anserine) content in the loin and ham cuts of female, Korean Native Black Pigs (KNBP) during cold storage for 10 days. The pH value of the loin and the ham cuts increased with an increase in the number of storage days. The lightness ($L^*$) of the loin cuts did not show any significant difference; however, the lightness of the ham cuts was decreased at storage day 10 (p<0.05). The redness ($a^*$) of the ham was higher than the redness of the loin (p<0.05) during the entire 10-days of storage. The water holding capacity of the loin was decreased from 78.5% to 67.9% during storage (p<0.05). The total number of microorganisms and coliforms was increased in both the loin and the ham during storage, and the initial total microbial contamination was higher in the ham cut (5.16 log CFU/g) than it was in the loin cut (4.87 log CFU/g). The carnosine content of the loin and the ham was in the range of 1.12-1.35 mg/ml and no significant difference was found between those two pork cuts. The anserine content of the ham cut was higher than it was in the loin cut until storage day 3. The ratio of carnosine and anserine increased with an increase in the number of storage days and it ranged from 27.6-59.7 for the loin cut and from 20.1-51.2 for the ham cut. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity of the loin and the ham cuts significantly decreased as the number of storage days increased. For both types of KNBP cuts, lipid oxidation and volatile basic nitrogen significantly increased after storage day 5. These results found that natural antioxidants carnosine and anserine decreased as the number of storage days increased, and anserine decreased more rapidly than carnosine (p<0.05).

• Journal of Food Hygiene and Safety
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• v.32 no.2
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• pp.154-162
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• 2017

The purpose of this study was to investigate the microbial reduction effect of chlorine dioxide and sodium hypochlorite in Korean chive. Korean chive inoculated with foodborne pathogens at the level of approximately 7~8 log CFU/g was treated with various concentration of chlorine dioxide (3, 4, 10, 25 and 100 ppm and sodium hypochlorite (100, 150 and 200 ppm) for 5, 10, 30 and 60 minutes. The treatment of 150 ppm sodium hypochlorite and 50 ppm chlorine dioxide for 30 min reduced the number of total bacteria in Korean chive up to 2.0 log CFU/g. Reduction of microbial levels was observed for all concentrations of sanitizers but their effectiveness did not correspond to their concentration. Due to the quality degradation, 50 ppm chlorine dioxide was not appropriate for Korean chive. Most effective reduction of microbial levels was observed when Korean chive were treated with 9 times more sanitizer in volume. For field application, the treatment of 150 ppm sodium hypochlorite showed 2.7 and 4.0 log CFU/g reductions for numbers of total bacteria and coliforms, respectively. Therefore, washing with sodium hypochlorite of a ratio of 1:9 (Korean chive : 150 ppm sodium hypochlorite (w/v)) for 30 minutes can reduce the number of foodborne pathogen in Korean chive.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.2
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• pp.139-147
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• 2021

Livestock manure is used as an organic fertilizer to replace chemical fertilizers after sufficient fermentation in an aerobic bioreactor. On the other hand, liquid manure disposal problems occur repeatedly because soil spraying is restricted during the summer when the crops are growing. To use liquid fertilizer (LF) as an additional nutrient source for crops, it is necessary to reduce the amount of suspended solids (SS) in the liquid fertilizer and secure stability problems against pathogenic microorganisms. This study examined the effects of the simultaneous SS removal and E.coli sterilization in the LF using the microbubble (MB) generator (FeMgO catalyst insertion). The remaining SS were further removed using the integrated microbubble and microfilter system. During the floating process in the MB device, the SS were removed by 57.9%, and the coliform group was not detected (16,200→0 MPN/100 mL). By optimizing the HRT of the integrated system, the removal efficiency of the SS was improved by 92.9% under the 0.1h of HRT condition. After checking the properties of the treated LF, 64.5%, 70.1%, 54.9%, and 51.5% of the TCOD, SCOD, PO4-P, and TN, respectively, were removed. The treated effluent from such an integrated system has a lower SS content than that of the existing LF and does not contain coliforms; therefore, it can be used directly as an additional fertilizer.

• Korean Journal of Environment and Ecology
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• v.36 no.2
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• pp.165-176
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• 2022

This study surveyed the characteristics of fish communities in Hwapocheon Wetland, Korea, from May to September 2020. The survey collected 735 objects in 21 species belonging to 7 families from 8 survey stations. The dominant and subdominant species were Hemiculter eigenmanni(23.8%) and Micropterus salmoides(10.3%), respectively. The next most abundant species were Zacco platypus(9.5%), Carassius auratus(9.4%), Pseudorasbora parva(9.0%), Squalidus chankaensis tsuchigae(6.7%), Acheilognathus macropterus(5.4%), Lepomis macrochirus(5.2%), Pseudogobio esocinus(4.1%), Opsariichthys uncirostris amurensis(3.7%), and Carassius cuvieri(3.3%). Among the fish species collected, one species, Culter brevicauda, was class II endangered wildlife designated by the Ministry of Environment, and one species,S. c. tsuchigae(4.8%), was endemic to Korea.Additionally, three exotic species (M. salmoides, L. macrochirus, and C. cuvieri) and one landlocked species (Rhinogobius brunneus) were collected. Compared to previous studies, the proportion of fish living in the running water area tended to decrease, the proportion of fish living in the water purification area tended to increase, and ecosystem-disturbing species (M. salmoides and L. macrochirus) tended to increase gradually. Results of fish community analysis showed that the mainstream stations (St. 1, 3, 4, 5, 6, and 8) had low dominance, but high diversity and richness, and other stations (St. 2 and 7) had high dominance but low diversity and richness. The river health (index of biological integrity) evaluated using fish was assessed as bad (6 stations), normal (1 station), and very bad (1 station). The water quality grade was assessed as slightly bad due to the chemical oxygen demand (COD), total organic content (TOC), suspended solid (SS), and total coliforms (TC). The annual water quality showed a gradually increasing trend of biological oxygen demand (BOD), COD, SS, and chlorophyll-a. The stable life of fish and the improvement of river health in Hwapocheon Wetland require water quality improvement and the systematic management of ecosystem-disturbing species (M. salmoidesand L. macrochirus).

• Journal of Food Hygiene and Safety
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• v.39 no.2
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• pp.109-117
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• 2024

This study investigated the microbial contamination of agricultural, livestock, and marine ingredients in 55 meal kits distributed across Gyeonggi-do, South Korea. Of the 55 meal kits, 48 contained agricultural ingredients, 43 contained livestock ingredients, and 16 contained marine ingredients. The detection rate of the total aerobic bacteria in the agricultural, livestock, and marine products was 100%. The average numbers of the total aerobic bacteria were 6.57 log colony-forming units (CFU)/g in the agricultural products, 4.60 log CFU/g in the livestock products, and 5.47 log CFU/g in the marine products. The coliform detection rates in the agricultural, livestock, and marine products were 81.25%, 69.77%, and 43.75%, respectively. The average numbers of coliforms were 2.83 log CFU/g in the agricultural products, 1.34 log CFU/g in the livestock products, and 1.12 log CFU/g in the marine products. Escherichia coli was detected in 13 livestock products (30.23%), with levels ranging from 0.70 to 2.36 log CFU/g. Contrastingly, E. coli was detected in only one marine product (6.25%) and was not detected in any agricultural products. The detection rates of fungi in agricultural, livestock, and marine products were 97.92%, 93.02%, and 93.75%, respectively. The average numbers of fungi were 3.82 log CFU/g for the agricultural products, 2.92 log CFU/g for the livestock products, and 2.82 log CFU/g for the marine products. The isolation rates of foodborne pathogens from the agricultural, livestock, and marine products were 35.42%, 37.21%, and 31.25%, respectively. Forty-five foodborne pathogens of seven species, including Bacillus cereus and Salmonella spp., were isolated from the raw materials of the agricultural, livestock, and marine products in 55 meal kits. To prevent foodborne diseases caused by meal kits, it is necessary to focus on washing, heating, and preventing cross-contamination during cooking.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.5
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• pp.585-592
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• 2012

This study was to investigate the quality characteristics and microbiological of simple preprocessed foods vege-ball with guava leaf powder (VB) for soup during storage at $4^{\circ}C$ and preparation of standard recipe. Lightness was increased during storage, but yellowness and redness were no significantly differences during storage, except for control. Hardness of VB increased with increasing guava leaves powder springness, cohesiveness significantly as a powder addition guava leaves was lower. DPPH, ABTS compared to the control showed higher levels in VB with increasing amounts significantly increased antioxidant activity (p<0.05). According to the sensory evaluation, VB 0.1% showed higher score in term of taste, flavor, overall preference. All the VB samples showed significantly lower values for acid, peroxide and than the control. Low level of total aerobic bacteria was detected during storage (<5.00 log CFU/g). Coliforms and yeast & mold were not detected during storage in VB samples. In conclusion, the addition of 0.1% with guava leaves powder would be useful way to enhance the anitoxidant quality and sensory characteristics of preprocessed food. The estimated storage was 8 days at $4^{\circ}C$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.2
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• pp.284-292
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• 2016

The purpose of this study was to analyze the personal hygiene status of foodservice employees as well as microbiological counts of their hands according to food safety education. A survey was conducted for employees who worked at five foodservice facilities, and the results of the survey were assessed using the SAS program (ver. 9.3). A total of 20 employees' hands were sampled to analyze aerobic plate counts (APCs), coliforms counts (CCs), and Staphylococcus aureus. The food safety education program was composed of four education sessions, including microbiological evaluation of employees' hands. According to the survey results, all employees wore a sanitary uniform, hair cap, and shoes. However, 96% of employees used the restroom wearing sanitary shoes, whereas just 20% of them washed their hands using the standard method. Additionally, employees washed hands after using the restroom (100%), before using single-use gloves (76%), after eating (76%). The results of the microbiological hazards analysis of foodservice employees' hands showed that the average numbers of APCs and CCs before cooking were 5.53 log CFU/hand and 2.95 log CFU/hand respectively, whereas the average numbers of APCs and CCs while cooking at foodservice facilities were 6.49 log CFU/hand and 3.29 log CFU/hand, respectively. Staphylococcus aureus was detected in 10% of their hands before cooking and 5% of their hands while cooking. The average numbers of APCs and CCs were significantly reduced before cooking as well as while cooking, and Staphylococcus aureus was not detected in any of the samples as the frequency of food safety education increased. In conclusion, this study shows that it is necessary for foodservice employees to regularly participate in food safety education with effective instruments in order to improve their hygiene level.

• Korean Journal of Poultry Science
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• v.37 no.4
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• pp.405-413
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• 2010

This study was carried out to determine the effect of dietary supplementation of quercetin and methoxylated quercetin extracted from onions on oxidation of chicken thigh during cold storage. For 35 days, 1-day-old 320 broiler chicks (Ross) were divided into 8 groups and supplemented the diet; basal diet only (T1), T1 with antibiotics (T2), vitamin E 20 IU (T3), vitamin E 200 IU (T4), quercetin 20 ppm (T5), quercetin 200 ppm (T6), methoxylated quercetin 20 ppm (T7), methoxylated quercetin 200 ppm (T8). After slaughtering the broilers, thigh meats were collected and analyzed the oxidation stability during storage at $4^{\circ}C$ for 7 days. Volatile basic nitrogen (VBN) was ranged from 10.98~15.37 mg% until day 3 and quercetin 20 ppm (T5) significantly reduced (p<0.05) the VBN value of thigh as much as antibiotics treatment group (T2). The supplementation of quercetin at a 200 ppm level significantly reduced 2-thiobarbituric acid reactive substances value when compared with the control. Supplementation of 20 ppm quercetin also affected fatty acid composition of chicken thigh and resulted in increase of C18:1w9 and decrease of C18:2w6 on day 3. In microbes of chicken thigh during storage, supplementation of 20 ppm quercetin significantly reduced total microbes compare to control on day 7 (p<0.05). There was no effect on the number of coliforms in thigh with quercetin diet. From these results, the dietary supplementation of 20 ppm of quercetin may have effects on enhancing oxidation stability.

• 한국유가공학회:학술대회논문집
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• 2002.11a
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• pp.23-40
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• 2002

This study was conducted to investigate the quality changes of the UHT(ultra-high temperature), LTLT(law temperature long time) and HTST(high temperature short time) treated milk samples by storage conditions for 6 months from August 2000 to February 2001. The UHT treated milk samples collected from 3 plants(A, B and C) were stored at l0$^{\circ}$C and room temperature(dark and light exposure) for 6 months, and the LTLT and HTST treated milk samples(D and E) were also stored for 30 days. The UHT pasteurized milk of A, B and C plant was treated at 130$^{\circ}$C for 2-3s, 133$^{\circ}$C for 2-3s and 135$^{\circ}$C for 4s, respectively. The UHT sterilized milk of A and B plant was treated at 140$^{\circ}$C for 2-3s and 145$^{\circ}$C for 3-4s, respectively. The LTLT milk of D plant was treated at 63$^{\circ}$C for 30 mins, and the HTST milk of E plant was treated at 72$^{\circ}$C for 15s. All of the raw milk samples collected from storage tank in 5 milk plants were showed less than 4.0 X 10$^5$cfu/ml in standard plate count, and normal level in acidity, specific gravity, and component of milk. Preservatives, antibiotics, sulfonamides and available chloride were not detected in both raw and heat treated milk samples obtained from 5 plants. One(10%) of 10 UHT pasteurized milk samples obtained from B plant and 2 (20%) of 10 from C were not detected in bacterial count after storage at 37$^{\circ}$C for 14 days, but all of the 10 milk samples from A were detected. No coliforms were detected in all samples tested. No bacteria were also detected in carton, polyethylene and tetra packs collected from the milk plants. A total of 300 UHT pasteurized milk samples collected from 3 plants were stored at room(3$^{\circ}$C ${\sim}$ 30$^{\circ}$C) for 3 and 6 months, 11.3%(34/300) were kept normal in sensory test, and 10.7%(32/300)were negative in bacterial count. The UHT pasteurized milk from A deteriorated faster than the UHT pasteurized milk from B and C. The bacterial counts in the UHT pasteurized milk samples stored at 10$^{\circ}$C were kept less than standard limit(2 ${\times}$ 10$^4$ cfu/ml) of bacteria for 5 days, and bacterial counts in some milk samples were a slightly increased more than the standard limit as time elapsed for 6 months. When the milk samples were stored at room(3$^{\circ}$C ${\sim}$ 30$^{\circ}$C), the bacterial counts in most of the milk samples from A plant were more than the standard limit after 3 days of storage, but in the 20%${\sim}$30%(4${\sim}$6/20) of the milk samples from B and C were less than the standard limit after 6 months of storage. The bacterial counts in the LTLT and HTST pasteurized milk samples were about 4.0 ${\times}$ 10$^3$ and 1.5 ${\times}$ 101CFU/ml at the production day, respectively. The bacterial counts in the samples were rapidly increased to more than 10$^7$ CFU/ml at room temperature(12$^{\circ}$C ${\sim}$ 30$^{\circ}$C) for 3 days, but were kept less than 2 ${\times}$ 10$^3$ CFU/ml at refrigerator(l0$^{\circ}$C) for 7 days of storage. The sensory quality and acidity of pasteurized milk were gradually changed in proportion to bacterial counts during storage at room temperature and 10$^{\circ}$C for 30 days or 6 months. The standard limit of bacteria in whole market milk was more sensitive than those of sensory and chemical test as standards to determine the unaccepted milk. No significant correlation was found in keeping quality of the milk samples between dark and light exposure at room for 30 days or 6 months. The compositions of fat, solids not fat, protein and lactose in milk samples were not significantly changed according to the storage conditions and time for 30 days or 6 months. The UHT sterilized milk samples(A plant ; 20 samples, B plant ; 110 samples) collected from 2 plants were not changed sensory, chemical and microbiological quality by storage conditions for 6 months, but only one sample from B was detected the bacteria after 60 days of storage. The shelflife of UHT pasteurized milk in this study was a little longer than that reported by previous surveys. Although the shelflife of UHT pasteurized milk made a significant difference among three milk plants, the results indicated that some UHT pasteurized milk in polyethylene coated carton pack could be stored at room temperature for 6 months. The LTLT and HTST pasteurized milk should be sanitarily handled, kept and transported under refrigerated condition(below 7$^{\circ}$C) in order to supply wholesome milk to consumers.

• Journal of Animal Science and Technology
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• v.45 no.4
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• pp.559-568
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• 2003

This study was carried out to investigate the effect of probiotics on the performance, nutrients digestibility, noxious gas emission and microflora population on the cecum of broilers. A total of 120 broilers, consisted of 4 treatments X 3 replicates X 10 broilers per replicates, were fed the experimental diets containing 0, 0.1, 0.3 and 0.5％ probiotics for 5 weeks. Broilers fed the diets containing 0.1 and 0.3％ probiotic had higher (p<0.05) body weight gain and feed conversion than those of the others from the 3rd to 4th week. Broilers fed 0.3％ probiotic had higher (p<0.05) body weight gain and feed conversion than those of the other levels from the 5th to 6th week. Broilers fed the diets containing 0.1% and 0.3％ probiotic had higher (p<0.05) body weight gain and feed conversion than those of the others from the 2nd to 6th week. Dry matter digestibility was significantly (p<0.05) improved with 0.3% probiotic. Emission of ammonia and sulfate hydrogen gas was significantly (p<0.05) decreased at 6th week. However, there was no (p<0.05) difference at the levels of 0, 0.1, 0.3 and 0.5% at the 4th weeks. There was an increase in the lactobacillus sp, but there was a decrease in the microflora population of coliforms in the cecum of broiler with 0.1% and 0.3% probiotics. These results indicated that the compound probiotics of 0.1${\sim}$0.3% were effective in the body weight gain, feed conversion, nutrients digestibility, noxious gas emission and microflora population on the cecum in broilers.