• Korean Journal of Food Science and Technology
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• v.46 no.2
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• pp.213-218
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• 2014

The purpose of this study was to investigate the bioavailability and nutritive functions of Nak-Dong rice or genetically modified ${\beta}$-carotene-biofortified rice (GM rice) in an experimental animal model. Wistar rats fed either GM rice or Nak-Dong rice did not show differences in bioavailability, growth, organ weights, or visceral fat, suggesting that the nutrient content of GM rice is compositionally equivalent to that of conventional Nak-Dong rice. In addition, GM rice showed improved nutritive function in terms of increased defecation, decreased lipids, and decreased blood glucose.

• Korean Journal of Food Science and Technology
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• v.33 no.3
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• pp.333-337
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• 2001

The effect of roasting of Omija (Schizandra chinensis Baillon) on the physicochemical properties and the sensory quality of the extract was investigated in order to improve the quality of Omija beverage. The response surface methodology was introduced to optimize the roasting condition of Omija based on the sensory quality of the extract. The titratable acidity, the soluble solid content and the reducing sugar content of the extract increased with a mild roasting, but decreased with an excessive roasting. Prolonged roasting at high temperature decomposed red pigment making the color of the extract lighter, less red and less yellow. A mild roasting of Omija improved the sensory quality of the extract, and the highest sensory quality of the extract was provided with the roasting at $180^{\circ}C$ for 10 min, indicating the optimum roasting condition of Omija. The extract of the roasted Omija was superior in sensory properties to that of the unroasted one.

• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.1018-1023
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• 2005

Simplified procedure was developed for concentrating and detecting poliovirus and norovirus in oysters. Viruses were seeded into oyster tissue homogenates and concentrated through polyethylene glycol (PEG) precipitation, chloroform or Freon extraction, with additional PEG precipitation. Amount of viruses was evaluated using poliovirus plaque assay. Virus recovery during concentration procedure was approximately 16.4-26.0%. For defection, viral RNAs in oysters were examined using one-step RT-PCR after extraction with Trizol. Dilution or capturing of viral RNA using silica gel membrane allowed viruses to be detected by RT-PCR, whereas viruses could not be removed using $QIAshredder^{TM}$ Homogenizer, which is effective in removing RT-PCR inhibitors in lettuce and hamburgers. Freon extraction, generally used to concentrate viruses found in food, could be substituted with chloroform extraction using this procedure; no difference could be observed between detection limits of whole oyster extracts and digestive organ extracts indicating that RT-PCR inhibitors were distributed evenly throughout whole tissues. Nested PCR greatly improved efficiency of this procedure. Overall, this procedure could remove sufficient amount of inhibitors to allow detection of norovirus in oysters.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.9
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• pp.1307-1313
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• 2011

This study was conducted to evaluate the effects of irradiation temperature on the physicochemical and sensory properties of Tarakjuk, milk porridge. Tarakjuk was gamma-irradiated at different temperatures of $25^{\circ}C$ (in room), $4^{\circ}C$ (in ice), and $-20^{\circ}C$ (in dry ice) at a dose of 10 kGy, and then autoclaved at $120^{\circ}C$ for 15 min for comparison. pH and Hunter's color value of Tarakjuk were not changed by irradiation regardless of the temperature. However, the TBA (2-thiobarbituric acid) value decreased as irradiation temperature was decreased. The viscosity of Tarakjuk irradiated in dry ice was significantly higher than that irradiated at room temperature and in ice (p<0.05). For the sensory evaluation, there were no significant differences in overall acceptability between non-treated Tarakjuk and that irradiated in dry ice. Flavor pattern analysis using an electronic nose with a SAW (surface acoustic wave) sensor determined that the main peaks at retention times 3.88 and 7.34 sec were related with off-flavor induced by irradiation and unique flavor of Tarakjuk, respectively. These results indicated that irradiation at freezing temperature improved quality deterioration of Tarakjuk by gamma irradiation. However, sensory quality of Tarakjuk irradiated at freezing temperature was still lower than that of non-irradiated Tarakjuk. Therefore, further research is needed to improve the quality of Tarakjuk using combined treatment such as addition of antioxidants and vacuum packaging method.

• Food Science and Preservation
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• v.21 no.2
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• pp.231-238
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• 2014

This study was performed to investigate the changes in antioxidant activity and quality characteristics of soy sauce with Gastrodia elata (GK) and oak mushroom (MK) in maturation period to develop a new Kanjang product with improved functional and sensory characteristics. The pH was decreased, and the total acidity was higher in GK at 25-day maturation period. Although the total sugar content increased at 15 days with GK, it was reduced after 20 days. The reducing sugar, however, showed no notable differences after 20 days. The protease activities of GK was rapidly increased after 20 days. The total polyphenol and flavonoid contents tended to be similar and dramatically increased after 15 days. On the other hand, the DPPH radical scavenging activity of MK was higher than that of GK. These results showed that the 20-day maturation period of GK greatly enhanced its antioxidant activity and quality characteristics. It is thus expected to be used as functional materials.

• Food Science and Preservation
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• v.20 no.4
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• pp.467-474
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• 2013

This study demonstrated that the physiochemical properties and anti-oxidants activities of soy sauce with Oak mushroom (MK) and Astragalus memyranaceus (AK) improved in sensory acceptability and functionality during the ripening period of 30 days. The pH content was reduced and the total acidity content was increased with time. The total sugar of AK and MK was higher than traditional soy sauce (TK), and the changes in amino nitrogen of the AK increased dramatically from 0.50 to 0.98%. During the antioxidant experiments, the total polyphenol and flavonoid contents increased at a steady rate and studies showed that the DPPH free radical scavenging activities were higher in all treatments except in the traditional soy sauce. According to the results of this study, the antioxidant activities of the AK and MK were higher than the TK, while the preference for the AK and MK was higher than the TK. In conclusion, the AK could be used as a functional soy sauce.

• Food Science and Preservation
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• v.15 no.1
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• pp.144-149
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• 2008

Physiological, sensory and microbiological evaluations were conducted during fermentation of Chungkookjang. with Choi-cha (non-fermented green tea) powder in efforts to improve the sensory quality of Chungkookjang. Growth of fermentative microorganisms in Chungkookjang was inhibited by Choi-cha; the pH and VBN value decreased as the concentration of Choi-cha increased. Brightness (L) and redness (a) of Chungkookjang fermented with Choi-cha were significantly decreased, resulting in the appearance of all samples fermented with Choi-cha being less attractive than was the control. The sensory quality of Chungkookjang was significantly increased when Choi-cha was added up to 3%, (w/v), and off-odor was reduced. The antioxidative property of Chungkookjang fermented with 3% (w/v) Choi-cha was significantly higher than that of the control. This result indicated that the sensory quality of Chungkookjang was improved by fermentation with 3% (w/v) of Choi-cha powder.

• Food Science and Preservation
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• v.22 no.5
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• pp.636-643
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• 2015

This study investigated changes in quality and sensory characteristics of soy sauce (Kanjang) with added Astragalus membranaceus (AK) to develop a new soy sauce product with improved sensory characteristics. The pure salinity slowly increased, but AK 10% decreased. The pH was a constant in all samples. The soluble solid content (Brix) increased after 2 months, but AK 10% decreased. With increased addition of Astragalus membranaceus (AM), the optical density increased after 4 months. The amino nitrogen increased in soy sauce with AK 5%. The total free amino acid content gradually increased in soy sauce with AK 5% aged for 6 months. As the addition of AM increased, the crude protein level decreased, but there was no difference between AK 0% and 5%. The sensory tests of AK 5% after 6 months showed higher acceptance. According to the aging period, the acceptability of AK 5% was the best. The results showed that soy sauce with of AK 5% and aged for 6 months exhibits greatly enhanced quality and sensory characteristics. Therefore, it is expected to be used as a natural resources in seasoning area.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.192-199
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• 2000

Lactic acid bacteria (LAB) fermented food was prepared from milk or egg white powder (EWP) and added with five kinds of freeze drying protectant (FDP). Effects of FDP on growth and acid production of LAB were investigated. Effects of FDP on organoleptic properties of LAB fermented food were also studied. (1) Some of FDPs showed protective effect against damage to Lactobacillus acidophilus in LAB fermented food during freeze drying, while FDP did not show any protective effect against damage to L. acidophilus during freezing. This protective effect differed with substrate and concentration of FDP (2) Optimum concentration of Tween 80 and ascorbate added to milk sample was 0.2 % (W/V) and 1 %(W/V), respectively. Optimum concentration of raffinose and ascorbate added to EWP sample was 3 %(W/V) and 1 %(W/V), respectively (3) Among FDPs added to L. casei fermented food, raffinose and ascorbate added to EWP sample showed FDP effect. Among FDPs added to L. delbrueckii fermented food, raffinose added to EWP sample showed FDP effect. (4) Samples added with MSG showed MSG taste. Milk sample added with ascorbate showed slightly more acid taste than reference sample, while taste of EWP sample added with ascobate did not differ with reference sample. Tween 80 added to milk sample or EWP sample improved texture of LAB fermented food.

• Food Science of Animal Resources
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• v.32 no.4
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• pp.504-511
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• 2012

The effects of the addition of wheat fiber on physico-chemical properties and sensory characteristics of pork loin cutlets were investigated to develop pork loin cutlets formulated with different concentrations of wheat fiber (0, 1, 2, 3, and 4%). The moisture content, ash content, pH, and lightness of pork loin cutlets increased with increasing wheat fiber levels (p<0.05). However, the fat content, calorie, redness, hardness, cohesiveness, gumminess, and chewiness decreased with increasing wheat fiber levels (p<0.05). The protein content, yellowness, and springiness of pork loin cutlets did not show significant difference (p>0.05). The sensory evaluation shows the greatest overall acceptability was ranked at the pork loin cutlets added with wheat fiber at 3%. Pork loin cutlets with added wheat fiber could be commercially acceptable meat products, and can be improved quality characteristics. The best results were obtained for pork loin cutlets with addition of 3% wheat fiber.