• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.4
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• pp.250-257
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• 2019

This study was carried out to investigate the effect of mountain grazing on growth performance and carcass characteristics of Hanwoo steers. Thirty two Hanwoo steers were randomly assigned. Control were fed concentrate + forage until 30 month of age. Treatment1 were fed concentrate + forage after mountain grazing from 8 to 13 months. Treatment2 and 3 were fed concentrate + forage after mountain grazing from 8 to 17 months. Hanwoo steers on Treatment 1 and 2 were slaughtered at the same age (30 months) as the control, and Hanwoo steers on Treatment 3 were slaughtered at 31 months. The average daily gain (ADG) were higher in the control than in the other treatments during the growing period (p<0.05). Carcass back fat thickness was thicker in the TRT 3 and marbling score was higher in the TRT 1 than in the other treatments; however, the differences were not statistically significant. There was no difference in the meat composition and shear force of the longissimus muscle according to the mountain grazing. However, the yellowness (b) of fat colors were significantly lower in the control than in the TRT 1 and TRT 2 (p<0.05). The effect of grazing on fatty acid composition was not constant. In conclusion, mountain grazing could reduce meat color without affecting the growth and meat quality of Hanwoo steers, and further research on the quality, yield and intake of grassland would be needed.

• Korean Journal of Food Science and Technology
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• v.42 no.4
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• pp.452-458
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• 2010

This study aimed at improving the packaging technology of Yukwa to improve the quality and extend the shelflife using secondary packaging. After packaging the Yukwa using an OPP film, P2, P3, and P4 packaging materials were applied secondarily. Various films including (1) P1: OPP (oriented polypropylene), (2) P2: P1+OPP/LLDPE (linear low density polyethylene), (3) P3: P1+PET (polyethylene terephthalate)/NY (nylon)/CPP (cast polypropylene) and (4) P4: P1+PET/AL (aluminum)/NY/CPP (P4) were used for packaging Yukwa. The experiment was conducted at $25^{\circ}C$ for 12 weeks. P1 showed the highest acid value score (1.26 mg KOH/g), and P3 had the highest peroxide value score (32.91 meq/kg) among all packaging groups. Nevertheless, these values did not exceed the guideline values of 2.0 g KOH/g and 40 meq/kg specified in the Korean food code. The overall color difference showed a tendency for decreasing Hunter 'L' values and increasing 'a' and 'b' values; however, no noticeable difference in the outer appearance was observed in any of the packaging treatments except in the P1 for greater than 10 weeks of storage. Some texture defects were observed in the Yukwa when the moisture contents dropped below 5%. The P4 packaging treatment had the lowest moisture permeability and showed the least rheological deterioration change, followed by P3 and P2. In conclusion, the use of a secondary packaging with less gas and moisture permeability was more effective for maintaining the quality and extending the shelf-life of Yukwa than other types of packaging material.

• Korean Journal of Food Science and Technology
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• v.42 no.4
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• pp.431-437
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• 2010

This study was carried out to determine the effect of gamma irradiation (3-20 kGy) on the antioxidant, antimicrobial activities and physical characteristics of Sargassum thunbergii (ST) extracts. When ST powder was treated by gamma irradiation, the yields and total phenolic compounds (TPC) of water extracts were increased, but radical scavenging activities were not changed. When ST extract was irradiated, the TPC and DPPH radical scavenging activities were increased. In addition, gamma irradiation of ST extract decreased viscosity and removed color. These results suggest that gamma irradiation would be a useful method for improving the physical characteristics of ST extract while maintaining native biological activities.

• Horticultural Science & Technology
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• v.32 no.6
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• pp.872-878
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• 2014

This study aimed to enhance storage and freshness of strawberry fruits and foliage vegetables by spray treatment with Chlorella vulgaris as a bio-fertilizer. The tested strain, C. vulgaris CHK0008, was isolated from an organically cultivated rice paddy and identified as C. vulgaris by its morphology and 18S rDNA and 23S rDNA sequence homology. We successfully cultured C. vulgaris CHK0008 in BG11 modified medium (BG11MM) and adjusted $2.15{\times}10^6cell/mL$ C. vulgaris CHK0008 to one OD value by measuring the optical density at 680 nm using a UV-vis spectrophotometer. The soluble solid content of 'Seolhyang' and 'Yukbo' strawberry fruits treated by spray application with C. vulgaris CHK0008 was enhanced by 22.2% and 11.5% respectively, compared to untreated controls. Additionally, the decay rates of treated 'Seolhyang' and 'Yukbo' strawberry fruits decreased 63.8% and 74.4% respectively, compared to untreated control. Surface color changes and chlorosis of leaves in leaf vegetables such as lettuce, kale, red ornamental kale, white ornamental kale and beet were observed in samples treated with water spray for 10 days after cold storage. However, the decay rate of leafy vegetables treated with foliar application of 25% C. vulgaris CHK0008 liquid culture was significantly decreased compared to that of the untreated control during storage at $4^{\circ}C$.

• Journal of Life Science
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• v.17 no.4 s.84
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• pp.540-545
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• 2007

The purpose of this research is to study the effects of feeding dietary citrus byproducts TMR (total mixed ration) on physicochemical properties and sensory characteristics of Korean native beef loin (KNBL). The samples for experiment consist of the KNBL not fed with citrus byproducts (TMR-0) and the KNBL fed with citrus byproducts during fattening period (TMR-1). The control (TMR-0) KNBL was fed by general practical feeding (roughages and concentrates were fed separately), while the TMR-1 KNBL was fed by the same as TMR-0 until 17 months yearling but was fed by citrus byproducts feeding for 10 months after that. The $L^*(lightness),\;a^*(redness)\;and\;b^*(yellowness)$ value were not significantly different between TMR-0 and TMR-1. The pH of TMR-1 was lower than that of TMR-0 (p<0.05), the VBN content, TBARS value and EDA were not significantly different between TMR-0 and TMR-1. The water holding capacity, frozen loss and cooking loss were not significantly different between TMR-0 and TMR-1, but thawing loss of TMR-0 was higher than that of TMR-1 (p<0.05). The hardness of TMR-0 was higher than that of TMR-1, and the springiness of TMR-1 was higher than that of TMR-0 (p<0.05), but the cohesiveness, gumminess, chewiness and shear force were not significantly different between TMR-0 and TMR-1. The pH and VBN content during storage were not significantly different between TMR-0 and TMR-1, but the TBARS value of TMR-1 stored during 4 weeks was lower than that of TMR-0 (p<0.05). In case of sensory score, the color and aroma of raw meat, and the taste, juiciness and palatability of cooked meat were not significantly different between TMR-0 and TMR-1. But the flavor and tenderness of TMR-1 were superior than those of TMR-0 (p<0.05)

• Journal of Life Science
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• v.25 no.1
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• pp.21-28
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• 2015

Genetic polymorphisms of adipocyte determination and differentiation factor 1 (ADD1) gene were screened in Hanwoo and Jeju Black cattle-derived commercial (JBC-DC) populations. The ADD1 genotypes were determined using the presence/absence of 84-bp fragment at intron 7 region. The association of ADD1 genotypes for economic traits was examined in both populations. In the Hanwoo steers, ADD1 D/- carcasses showed significantly thicker backfat levels than those from WW (p<0.05). However, the thickest level of backfat appeared in WD heterozygotes, whereas thicker backfat did not appear in DD homozygotes in the JBC-DC population (p<0.05), leading to the supposition that synergic effects of alleles W and D increase backfat deposition. On the other hand, there was no association between the ADD1 genotypes and intramuscular fat deposition measured as meat quality index and marbling score. From these results, we concluded that the bovine ADD1 affected the backfat in subcutaneous tissue, rather than intramuscular fat in muscle tissue. In addition, the DD animals showed higher levels of meat color than those from W/- (p<0.05). Interestingly, a highly significant difference was found between the genotypes and carcass weights only in the JBC-DC population, and D/- animals were heavier by more than 38 kg than those from WW (p<0.001). The results of this study reveal faster growth rate and differences in steer productivity according to genotypes of the ADD1 gene. These findings demonstrate that ADD1 genotypes may effectively function as molecular genetic markers for the improvement of Hanwoo and Jeju Black cattle-related crossbreeding systems.

• Journal of Life Science
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• v.19 no.1
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• pp.94-100
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• 2009

This study was carried out to examine the antimicrobial effects of grapefruit seed extract (GSE) and processed sulfur solution (PSS) against human skin pathogens: Malassezia furfur, M. restricta, Propionibacterium arnes, Trichophyton mentagrophytes and T. rubrum. The antimicrobial effects of GSE and PSS were tested by agar diffusion method and micro broth dilution method. As the results, the MIC values of GSE against M. furfur, M. restricta, P. acnes, T. mentagrophytes and T. rubrum were 3.91, 3.91, 0.004, 0.024, and $0.012{\mu}l/ml$, respectively. The MIC values of PSS were 0.03, 0.03, 0.156, 0.003, and $0.012{\mu}l/ml$, respectively. Antimicrobial activity of skin care emulsion products containing 0.5% GSE and 0.5% PSS against human skin pathogens were 5.2, 4.3, 8.0, 9.5 and 12.8 mm, respectively. Refractive index, pH, viscosity and color value of skin care emulsions containing GSE and PSS were measured. According to these results, it was concluded that the GSE and PSS were the promising sources of antibacterial agent which could be useful for skin and hair care products as well as for the alternative medicine development in treatment of certain types of skin ailments.

• Journal of Food Hygiene and Safety
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• v.25 no.3
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• pp.251-257
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• 2010

The experiment was conducted to find out the nutritive value and microbial status of different wholesale cuts of goat carcass. The meat sample (4 cuts from each animal $\times$ 3 different age groups $\times$ 3 animals in each group = 36 samples) was obtained from 1-, 2-, and 3-year aged goats. The whole sale cuts were shoulder, rack, loin and leg of each goat carcass. To assess the quality of meat sample, the general appearance, color, smell, juiciness, proximate composition, pH, total bacteria, coliform bacteria, and yeast were studied. The mean pH value of different cuts ranges from 5.65-5.69 didn't differ significantly, but due to age differences the pH values (5.59-5.74) differed significantly (p < 0.01). The values of juiciness in different ages ranged from 32.24-42.10% which differed significantly (p < 0.01). The marbling of the cuts of rack portion was more pronounced than that of other cuts. The ranges of crude protein (CP) content of goat carcass (20.78-27.71%) differed significantly (p < 0.01) and leg portion contained higher CP than other portion. Fat contents of different cuts ranged from 2.66-11.47% differed significantly (P < 0.01). The moisture content of the carcass differed significantly which ranged from 69.20-73.31%. The ash content of the cuts of 1-year aged groups (0.99 $\pm$ 0.13%) was higher than that of other age groups and differed significantly (P < 0.01). The calcium (Ca) content did not differ significantly. The phosphorus (P) content was higher in one year old goat (0.15 $\pm$ 0.03%) than that of the goats of other ages. The total viable count (TVC) content of microorganisms ranging from 5.05-5.15 log cfu/g at different ages did not differ significantly. The coliform count (CC) of different cuts differed significantly (P < 0.01) which ranged from 2.56-3.05 log cfu/g; it also differed significantly (P < 0.05) in different ages (2.79-2.84 log cfu/g) and was higher in 1 year old goat carcass. The yeast count differed significantly in different cuts (P < 0.01) and ages (P < 0.05). From the study it is concluded that the age and different wholesale cuts have direct influence on quality of goat carcass.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.204-212
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• 1994

To estimate the possibility of wine-making with Korean dried persimmon, its homogenized and filtered solution was fermented at $15^{\circ}C$ and $25^{\circ}C$ for 12 weeks with Saccharomyces cerevisiae (Japan Alcoholic Beverage Association N0.7). Sugars of dried persimmon were mainly composed of 27.02% of glucose, 19.81% of fructose and 5.12% of mannose. In the fermentation at $25^{\circ}C$, glucose was almost completely consumed in 8 days, but fructose and mannose were consumed up to 64% and 74%, respectively, in the same period and were not utilized any more afterwards. In the fermentation at $15^{\circ}C$, 75% of glucose, 20% of fructose and 49% of mannose were consumed in 8 days and these sugars were continuously utilized for 12 weeks. Organic acids in the homogenized and filtered solution were levulinic acid (148.6 mg%), 4-methylvaleric acid (73.5 mg%), oxalic acid (28.7 mg%), acetic acid (8.5 mg%), N-butyric acid (8.4 mg%) and succinic acid (6.7 mg%). Irrespective of fermentation temperature, levulinic acid rapidly reduced according to progression of fermentation. Oxalic acid, N-butyric acid and succinic acid decreased at 2nd day of fermentation, and then increased at 4th and 6th days and subsequently decreased again under the levels of the solution. Acetic acid and 4-methylvaleric acid increased with the proceeding of fermentation and at 12th week of fermentation these contents were more than those of the solution. The contents of total free amino acid significantly reduced at 2th day of fermentation and then increased to the level of the solution at 12th week irrespective of fermentation temperature. Ethanol content rapidly increased to the levels of 5.3(v/v) at $15^{\circ}C$ and 9.4%(v/v) at $25^{\circ}C$ to 8th day after fermentation, but at 12th week its content was 14.5%(v/v) at $15^{\circ}C$ and 9.4%(v/v) at $25^{\circ}C$. The higher alcohots identified were 2-methyl-l-propanol, 3-methyl-ibutanol, 2-methyl-l-butanol and 2-methyl-2-propanol and the range of those contents was from 0.001% (v/v) to 0.06%(v/v). The color of the wine fermented at $15^{\circ}C$ was slightly superior but flavor and taste were slightly superior in the wine fermented at $25^{\circ}C$.

• The Korean Journal of Food And Nutrition
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• v.29 no.5
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• pp.618-627
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• 2016

This study evaluated the hydration, gelatinization, and saccharification properties of rice processing for beverage development. The properties of rice were studied on 10 rice cultivars (Samkwang, Ilpum, Seolgaeng, Anda, Dasan-1, Goami-4, Danmi, American rice, Chinese rice, and Thai rice) and employing four kinds of pre-treatment methods (dry grain, wet grain, dry flour, and wet flour). The results showed that moisture content of rice was between 11.88~15.26%. Increase in soaking time along with highest water absorption was noted in American rice cultivar (46.81%). The water binding capacity of Thai rice was higher when compared to that of other rice flours. In addition, solubility and swelling power of rice were 4.52~26.65% and 0.19~2.05%, respectively. The amylose content of Goami-4 was higher in rice processing. Using a rapid visco analyzer (RVA), the initial pasting temperature of Danmi cultivar was found to be the highest; the peak viscosities of Anda cultivar and Dasan-1 cultivar, and Chinese rice were higher than of those of other rice flours. After saccharification, the pH, soluble solids content, and reducing sugar content of rice processed through different pre-treatment methods were in the range of 6.22~7.08, $4.67{\sim}16.07^{\circ}Brix$, and 0.35~11.67% (w/w), respectively. In terms of color values, the L-value of dry grain, a-value of wet (grain, flour), and b-value of dry sample (grain, flour) were found to be the highest. Assessment of various factors and cultivars characteristics of the raw grains are of importance in the development of rice beverage.