• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.5
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• pp.469-476
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• 1986

Proteolytic activity of the tissue extracts from the muscle of mackerel, Scomber japonicus, and sardine, Sardinops melanostcta, was comparence with referenced to the optimum reaction condition. Thermal stability and change of proteolytic activity of the tissue extracts during storage were investigated. The existence of acid, weak acid and alkaline proteinase was identified in the ordinary and dark muscle of the mackerel and sardine. Specific activity of acid proteinase was stronger than weak acid or alkaline proteinase in the both fish. The proteolytic activity of the tissue extracts on the optimum reaction condition was: ordinary muscle of mackerel, 0.12 nM-Tyr. eq./mg-prot. /min. at pH 3.0 and $50^{\circ}C$; dark muscle of mackerel, 0.36 nM-Tyr. eq./mg-prot. /min. at pH 3.0 and $45^{\circ}C$; ordinary muscle of sardine, 0.45 nM-Tyr. eq./mg-prot. /min. at pH 2.4 and $45^{\circ}C$; dark muscle of sardine, 0.24 nM-Tyr. eq./mg-port. /min. at pH 2.4 and $45^{\circ}C$. The proteinases distributed in the muscle of mackerel and sardine were stable with the heat treatment at $45^{\circ}C$ for 5 minutes, but those in the dark muscle of mackerel was stable with the treatment at $5^{\circ}C$ for 5 minutes. The proteinases from the muscle were slowly inactivated with the whole storage days at $5^{\circ}C\;and\;-15^{\circ}C$, those were more stable at $-15^{\circ}C\;than\;5^{\circ}C$ storage.

• 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 the Korean Society of Food Science and Nutrition
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• v.37 no.11
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• pp.1427-1434
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• 2008

This study was aimed to compare nutrition knowledge, dietary attitude and habit of elementary school children with and without education. Eighty-four subjects with unbalanced eating behavior were selected and assigned to either control or education group. The subjects in education group participated in a nutrition education program once a week for 8 weeks. The contents of nutrition education were on food tower, balanced nutrition, nutrient function, food group, importance of breakfast, and nutrition label, etc and the program was performed by a school dietitian. The effects of education was assessed by self-administered questionnaire prior to and after nutritional education. Nutrition knowledge except on snack, dietary self-efficacy except on low fat/ low calorie, attitude except on functional food and favorite, and general dietary habits of children in education group were significantly improved while those in control group showed no changes. Also, factors for unbalanced eating was improved by nutrition education indicating the need for correction on unbalanced eating was diminished. However, children's adherence to snack, instant and fast food remained to be corrected. The dietary habit of balanced eating was improved by education reducing the percentage of unbalanced eating on grain and meat.fish.milk groups. The nutrition education appears to be effective to provide nutrition knowledge thereby to improve dietary attitude, dietary self-efficacy, and partly to reduce children's unbalanced eating factor.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.8
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• pp.1166-1173
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• 2014

This study investigated the detoxification effects of enzymatic hydrolysate from oyster on acetaminophen-induced toxicity using HepG-2 cells. Oyster hydrolysate was made with 1% Protamex and 1% Neutrase after treatment with transglutaminase (TGPN) or without (PN). Two types of oyster hydrolysate were added to human-derived HepG-2 hepatocytes damaged by acetaminophen, after which the survival rate of HepG-2 cell was measured. In addition, glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) activities in the culture media were evaluated. The survival rates of HepG-2 cells were $136.2{\pm}1.4%$ at $100{\mu}g/mL$ of TGPN and $179.6{\pm}3.8%$ at $200{\mu}g/mL$ of TGPN. These cell survival rates were higher compared to that of the negative control group ($60.7{\pm}3.2%$) treated only with acetaminophen. GOT activity was $38.3{\pm}0.2$ Karmen/mL in the negative control group, whereas it was $19.9{\pm}0.5$ for TGPN ($200{\mu}g/mL$) and $22.0{\pm}2.4$ Karmen/mL for PN ($200{\mu}g/mL$). GOT and GTP activities were shown to be dependent on TGPN concentration, and significant reduction in activities could be conformed. The detoxification efficacy of TGPN was higher compared to that of PN. These results suggest that oyster hydrolysate has potential as a healthy food or pro-drug for liver protection.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.2
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• pp.217-222
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• 2008

The aim of the present study was to evaluate the effect of marination with mixed salt (NaCl, $CaCl_2$, and phosphate) and kiwi juice and of different cooking methods for pork loin-based products in order to establish the basic database for increasing the consumption of pork loin in Korea. Diced chilled pork loin ($2{\times}2{\times}2\;cm$) was marinated in 4 different treatments: no additives (T1), salt mix only (T2), kiwi juice only (T3), and salt mix+kiwi juice (T4). The mixed salt was prepared by the addition of NaCl, $CaCl_2$, and phosphate dissolved in water (10% of pork loin weight) at concentrations of 0.5, 0.5, and 0.3% per pork loin weight, respectively. The amount of kiwi juice was 10% of pork loin weight. After marination for 24 hrs at $4^{\circ}C$, the samples were cooked with different methods including roasting with Kimchi, pan broiling, and simmering. After simmering, pH of pork loin of T1 and T2 was higher than that of T3 and T4 (p<0.05), while that of roasted with Kimchi and pan broiled did not show any difference. Water holding capacity of T4 after pan broiling was higher than that of T1, T2, and T3 (p<0.001) and shear force of T4 was lower than other treatments. Also flavor and acceptability of T4 after pan broiling were scored higher by 11 sensory panelists (p<0.05). From this result, the pork loin-based products marinated with mixed salt and kiwi juice with pan broiling would be preferred by consumers as one of the methods to promote the consumption of pork loin in Korea.

• Korean Journal of Environmental Agriculture
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• v.30 no.3
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• pp.295-303
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• 2011

BACKGROUND: Anaerobic digestion process is recently adapted technology for treatment of organic waste such as animal manure because the energy embedded in the waste can be recovered from the waste while the organic waste were digested. Ever increased demand for consumption of meat resulted in the excessive use of antimicrobials to the livestocks for more food production. Most antimicrobials administered to animals are excreted through urine and feces, which might highly affect the biological treatment processes of the animal manure. The aim of this study was to investigate the effects of antimicrobials on the efficiency of anaerobic digestion process and to clarify the interactions between antimicrobials and anaerobes. METHODS AND RESULTS: The experiment was consisted of two parts 1) batch test to investigate the effects of individual antibiotic compounds on production of methane and VFAs(volatile fatty acids), and removal efficiency of organic matter, and 2) the continuous reactor test to elucidate the effects of mixed antimicrobials on the whole anaerobic digestion process. The batch test showed no inhibitions in the rate of methane and VFAs production, and the rate of organic removal were observed with treatment at 1~10 mg/L of antimicrobials while temporary inhibition was observed at 50 mg/L treatment. In contrast, treatment of 100 mg/L antimicrobials resulted in continuous decreased in the rate of methane production and organic removal efficiency. The continuous reactor test conduced to see the influence of the mixed antimicrobials showed only small declines in the methane production and organic matter removal when 1~10 mg/L of combined antimicrobials were applied but this was not significant. In contrast, with the treatment of 50 mg/L of combined antimicrobials, the rate of organic removal efficiency in effluent decreased by 2~15% and the rate of biogas production decreased by 30%. CONCLUSION(s): The antimicrobials remained in the animal manure might not be removed during the anaerobic digestion process and hence, is likely to be released to the natural ecosystem. Therefore, the efforts to decline the usage of antimicrobials for animal farming would be highly recommended.

• Journal of Nutrition and Health
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• v.55 no.1
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• pp.21-35
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• 2022

The recommended meal composition allows the general people to organize meals using the number of intakes of foods from each of six food groups (grains, meat·fish·eggs·beans, vegetables, fruits, milk·dairy products and oils·sugars) to meet Dietary Reference Intakes for Koreans (KDRIs) without calculating complex nutritional values. Through an integrated analysis of data from the 6th to 7th Korean National Health and Nutrition Examination Surveys (2013-2018), representative foods for each food group were selected, and the amounts of representative foods per person were derived based on energy. Based on the EER by age and gender from the KDRIs, a total of 12 kinds of diets were suggested by differentiating meal compositions by age (aged 1-2, 3-5, 6-11, 12-18, 19-64, 65-74 and ≥ 75 years) and gender. The 2020 Food Balance Wheel included the 6th food group of oils and sugars to raise public awareness and avoid confusion in the practical utilization of the model by industries or individuals in reducing the consistent increasing intakes of oils and sugars. To promote the everyday use of the Food Balance Wheel and recommended meal compositions among the general public, the poster of the Food Balance Wheel was created in five languages (Korean, English, Japanese, Vietnamese and Chinese) along with card news. A survey was conducted to provide a basis for categorizing nutritional problems by life cycles and developing customized web-based messages to the public. Based on survey results two types of card news were produced for the general public and youth. Additionally, the educational program was developed through a series of processes, such as prioritization of educational topics, setting educational goals for each stage, creation of a detailed educational system chart and teaching-learning plans for the development of educational materials and media.

• Journal of Life Science
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• v.34 no.1
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• pp.18-27
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• 2024

Laying hens are known to be able to 'bio-accumulate' the health-promoting ingredients of their diet into eggs. The purpose of this study was to characterize lignan-rich eggs as functional food fed with Schisandra fruit by-product (SCP). Experimental diets were formulated using yellow corn, rice bran, soybean meal, fish meal, meat bone meal, poultry meal, vitamin premix, mineral premix, CaCO₃, and supplemented Schisandra chinensis by-product. This experiment conducted a completely randomized design with 5 treatments for 5 laying hens. Levels of SCP were fed control diet or each formulated diet containing 1%, 3%, 5% and 7% SCP powder. The weight of eggs and the lignan content in white and yolk of egg were investigated every 7 days. Egg production and egg weight were not affected by diet at less than 5% SCP in the diet, but were significantly reduced when the diet was supplemented with a high concentration of 7% SCP after 3 weeks. Yolks and white in eggs were analyzed by using a high performance liquid chromatography (HPLC) to determine the lignans profile. Higher dietary SCP supplementation significantly increased gomisin N and schisandrin C in Acetonitrile (p<0.05). Gomisin N in egg white increased in a concentration-dependent manner, but shisandrin C not detected. These results indicated that the use of SCP powder in layering diets was effective in egg quality and for the production of lignans fortified eggs. In conclusion, dietary supplementation of Schisandra by-product with less than 5% can produce lignans-enrich eggs used as functional foods.

• 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.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.1
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• pp.41-51
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• 1987

This study was carried out to prepare powdered smoked-dried mackerel which can be used as a soup base, and to examine storage stability and the taste compounds of Products. Raw mackerel are filleted, toiled for 10 minutes and pressed to remove lipids, and then soaked in extract solution of skipjack meat. This soaked mackerel are smoked 3 times to $10-12\%$ moisture content at $80^{\circ}C$ for 8 hours. And the smoked-dried mackerel were pulverized to 50 mesh. Finally, the powdered smoked-dried mackerel were packed in a laminated film $bag(PET/Al\;foil/CPP:\;5{\mu}m/15{\mu}m/70{\mu}m,\;15\times17cm)$ with air(product C), nitrogen(product N) and oxygen absorber(product O), and then stored at room temperature for 100 days. The moisture and crude lipid content of powdered smoked-dried mackerel was $11.3-12.3\%,\;12\%$, respectively, and water activity is 0.52-0.56. And these values showed little changes during storage. The pH, VBN and amino nitrogen content increased slowly during storage. Hydrophilic and lipophilic brown pigment formation showed a tendency of increase in product(C) and showed little change in product(N) and (O). The TBA value, peroxide value and carbonyl value of product(N) and (O) were lower than those of product (C). The major fatty acids of products were 16:0, 18:1, 22:6, 18:0 and 20:5, and polyenoic acids decreased, while saturated and monoenoic acids increased during processing and storage of products. The IMP content in products were 420.2-454.2 mg/100 g and decreased slightly with storage period. And major non-volatile organic acids in products were lactic acid, succinic acid and $\alpha-ketoglutaric$ acid. In free amino acids and related compounds, major ones are histidine, alanine, hydroxyproline, lysine, glutamic acid and anserine, which occupied $80.8\%$ of total free amino acids. The taste compounds of powdered smoked-dried mackerel were free amino acids and related compounds (1,279.4 mg/100 g), non-volatile organic acids(948.1 mg/100 g), nucleotides and their related compounds (672.8 mg/100 g), total creatinine(430.4 ntg/100 g), tetaine(86.6 mg/100 g) and small amount of TMAO. The extraction condition of powdered smoked-dried mackerel in preparing soup stock is appropriate at $100^{\circ}C$ for 1 minute. Judging from the results of taste and sensory evaluation, it is concluded that the powdered smoked-dried mackerel can be used as natural flavoring substance in preparing soups and broth.