• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.6
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• pp.977-985
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• 2002

In order to improve the quality of traditional kochujang, submaterials like sea tangle and chitosan were added to kochujang and their effects on microbial characteristics, enzyme activities and physicochemical characteristics were investigated for 24 weeks of fermentation. The activities of $\alpha$,$\beta$-amylase in kochujmg were higher in sea tangle added at 2% level and chitosan added at 0.1% level. However, acidic protease activity decreased as the ratio of submaterials increased. Viable cells of yeasts in the kochujang increased rapidly for 4~8 weeks of fermentation, and bacterial counts decreased in submaterials added groups. Moisture contents of kochujang increased until 12 weeks of fermentation, but water activity decreased. As the ratio of sea tangle increased, water activity decreased. Consistency of kochujang increased after middle of fermentation, and they increased remarkably by addition of sea tangle. The degree of increase in total color difference ($\Delta$E) of sea tangle added group was lowest. The titratable acidity of kochujang decreased after 4 weeks, and they changed a little by addition of chitosan. Amino nitrogen contents of kochujang increased as mixing ratio of submaterials increased in the late period of aging. Ammonia nitrogen contents was lower in chitosan added kochujang at 24 week of fermentation. Reducing sugar contents of kochujang increased rapidly for 4~8 weeks of fermentation, and they increased as the ratio of chitosan increased. Ethanol contents of kochujang increased until 12~16 weeks of fermentation, with lower values in sea tangle added group. After 24 weeks of fermentation, the result of sensory evaluation showed that 0.1% chitosan added kochujang were more acceptable than sea tangle added kochujang in the taste, color and overall acceptability.all acceptability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.4
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• pp.621-628
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• 2002

Effect of the thickness of packaging film on the ripening of mature-green mume (Prunus mume Sieb. et Zucc) fruit was investigated by measuring physicochemical changes of the fruit during storage. Fruits were packaged using low density polyethylene (LDPE) films with thicknesses of 20, 30, and 40$\mu$m and stored at the room temperature. The physicochemical properties such as contents of various pectic substances, molecular weight distribution of soluble pectic substances, and surface image of the fruit were determined during storage of 8 days. In general, regardless of the thickness of the films applied, a content of water-soluble pectin (WSP) in the fruit was increased during storage, but both contents of HCI- soluble pectin (HSP), and Ca and Mg in total alcohol-insoluble solids were decreased. Sephacryl S-300 gel filtration study revealed that fractions of high molecular weight HSP and WSP decomposed into lower molecular weight pectins during storage. The scanning electronic microscope also identified a significant structural change of the fruit skin over the storage time. It could be concluded from the results that fruits packaged with LDPE 30${\mu}{\textrm}{m}$ film maintained the highest physicochemical quality of green mume fruit during storage.

• Korean Journal of Food Science and Technology
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• v.45 no.3
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• pp.339-344
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• 2013

Application of intense pulsed light (IPL) treatment is an emerging technology with interesting prospects in food preservation. However, information concerning the factors affecting the inactivation of microorganisms and their impact on the quality of fresh-cut food is scarce. In this study, the effects of IPL treatment on the microbial inactivation and physicochemical change in paprika were determined. The viability of bacteria in paprika treated with IPL decreased slightly with the treatment time. In addition, water content was slightly decreased after IPL treatment regardless of the color of paprika. However, except in red paprika, sugar content increased after IPL treatment. The pH of paprika increased in all samples, and the polyphenol content decreased with treatment time, but these differences were very small. After IPL treatment of paprika, vitamin C content increased in yellow and red samples. Hunter color values-lightness (L), redness (a), and yellowness (b)-increased in red paprika, but all values decreased in orange paprika.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1129-1134
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• 2003

Changran jeotkal, a Korean traditional fermented seafood, was prepared as a pilot scale using a commercial method and irradiated at 0, 2.5, 5.0 and 10 kGy by gamma ray to investigate possibilities for further industrial application. To see the effectiveness and rapid industrialization, hot pepper powder was irradiated at 10 kGy and manufactured the changran jeotkal (HP-10 kGy) as same method since the hot pepper powder was approved legally for gamma irradiation in Korea. The content of volatile basic nitrogen and amino nitrogen was significantly reduced by gamma irradiation in all storage periods. Amino nitrogen contents of 0, 2.5, 5.0, 10 kGy and HP-10 kGy were 98.9, 98.5, 92.4, 88.0 and 93.1mg%, respectively after 12 week of storage at $10^{\circ}C$. In total, 8 kinds of biogenic amines were found from the samples, and the contents in the gamma irradiated changran Jeotkal were lower than those of the control during storage. The sample of HP-10 kGy showed similar physicochemical characteristics to the sample irradiated as $2.5{\sim}5.0\;kGy$. Results indicated that gamma irradiation of fermented seafood products such as seasoned changran jeotkal improved quality stability, thus, we recommend gamma irradiation for industrial application.

• Journal of Animal Science and Technology
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• v.58 no.6
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• pp.23.1-23.17
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• 2016

Background: The functionality of myofibrillar proteins is a major factor influencing the quality attributes of muscle foods. Nonetheless, the relationships between muscle type and oxidative changes in chevon during ageing are meagrely elucidated. Postmortem changes in antioxidant status and physicochemical properties of glycolytic gluteus medius (GM) and oxidative infraspinatus (IS) muscles in goats were compared. Methods: Twenty Boer bucks (9-10 months old, body weight of $36.9{\pm}0.725kg$) were slaughtered and the carcasses were subjected to chill storage ($4{\pm}0.5^{\circ}C$). Analyses were conducted on GM and IS muscles sampled on 0, 1, 4 and 7 d postmortem. Results: Chill storage did not affect the antioxidant enzyme activities in both muscles. The IS had greater (P < 0.05) superoxide dismutase and catalase activities than GM. Carotenoid and tocopherol contents did not differ between muscles but decreased (P < 0.05) over storage. The IS had higher (P < 0.05) glycogen and ultimate pH and lower (P < 0.05) shear force and cooking loss than GM. The carbonyl content, % metmyoglobin, drip loss and TBARS increased (P <0.05) while free thiol, metmyoglobin reducing activity (MRA), shear force and myoglobin decreased (P < 0.05) over storage. Muscle type had no effect (P > 0.05) on free thiol, MRA and TBARS. The GM had lower (P < 0.05) redness on d 0 and 1 than IS while the IS had greater carbonyl, % metmyoglobin and drip loss than GM on d 7. The reflective density of slow myosin heavy chain (MHC) was higher (P < 0.05) while the density of fast MHC and actin was lower (P < 0.05) in IS than GM. Regardless of muscle type, the density of MHC decreased (P < 0.05) while that of actin was stable over storage. Nonetheless, the degradation of fast and slow MHC was greater (P < 0.05) in IS than GM. Muscle type had no effect (P > 0.05) on consumer preference for flavour, juiciness and overall acceptability. However, IS had higher (P < 0.05) tenderness score than GM on d 1 and 4 postmortem. Intramuscular fat was higher (P< 0.05) in IS compared with GM. Fatty acid composition did not differ between the muscles. However, GM had lower (P < 0.05) n-6/n-3 ratio than IS. The n-3 and n-6 PUFA declined (P < 0.05) while the SFA increased (P < 0.05) over storage. Conclusion: The changes in myofibrillar proteins and physicochemical properties of goat meat during postmortem chill storage are muscle-dependent.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.3
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• pp.219-225
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• 2011

The physicochemical properties of rice endosperm from five rice varieties and effects of milling on baking bread properties of rice flour were investigated. Five rice varieties exhibited different level of amylose content. The ratio of longer amylopectin chain length to the distribution of endosperm starches was the highest in Goami3. According to the RVA measurement of rice flours, the pasting temperatures of Seolgaengbyeo and Goamibyeo were lower than those of the other rice varieties. There were differences in the changes of swelling power of rice flour under increasing temperature. Each rice flour sample for bread-making was processed into two different particle size by using an air-classification mill, and significant differences were observed among cultivars in the average particle size and damaged starch content of rice flours. Rice flour of Seolgaengbyeo with fine particle size showed the highest value in specific volume after baking.

• Korean Journal of Food Science and Technology
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• v.35 no.3
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• pp.393-398
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• 2003

Effects of convection oven dehydration conditions on the physicochemical and sensory properties of ginkgo nut powder were examined using three types of pre-treatment on ginkgo nuts: coarse grinding of ginkgo nut (GR); coarse grinding followed by 1 min blanching (GB); 3 min blanching followed by coarse grinding (BG). Pretreated ginkgo nuts were dried in convection oven at 70 and $80^{\circ}C$ to the moisture content of approximately 5%. Rehydration rate, swelling power, solubility, lightness, and greenness of GB ginkgo nut powder dried at $70^{\circ}C$ were the most similar to those of freeze dried one. GR and GB samples dried at $70^{\circ}C$ had higher sensory values of green color and ginkgo nut flavor. Ginkgo nut powder with desirable quality attributes could be produced by drying GB in convection oven at $70^{\circ}C$ for 10 hr.

• Korean Journal of Food Science and Technology
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• v.35 no.3
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• pp.386-392
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• 2003

Physicochemical and microbiological changes of grape wine fermented and aged at 25 and $15^{\circ}C$ for 2 and 14 weeks, respectively, were investigated. Viable bacterial cell number, $3.3{\times}10^2\;CFU/mL$ at the beginning of fermentation, increased to $2.3{\times}10^6\;CFU/mL$ after 2 weeks, then decreased to $1.9{\times}10^3\;CFU/mL$ after 14 weeks. Viable yeast cell number increased from $2.8{\times}10^2\;to\;2.2{\times}10^7\;CFU/mL$ during fermentation, then decreased to $1.6{\times}10^4\;CFU/mL$ after aging. Turbidity, pH, total sugar content, reducing sugar content, and solid content of grape wine decreased during fermentation, whereas acidity and alcohol content increased to 0.64 and 8.4%, respectively. Most physicochemical properties did not change significantly during aging. When grape wine was filtered through $0.45-{\mu}m$ nitrocellulose membrane, followed by various ultrafiltration membranes with different molecular weight cut-off values, Biomax 100K membrane with $100\;L/m^2/hr$ (LMH) of initial flux was chosen for ultrafiltration process. These membrane filtration treatments resulted in complete removal of microorganisms and decreases in turbidity, reducing sugar, and solid content. Physicochemical properties of wine did not change, and no microorganisms were found during storage at $30^{\circ}C$ for 12 weeks.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.7
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• pp.1104-1111
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• 2014

To investigate major characteristics affecting the consumer acceptability of Cheonggukjang, the physicochemical characteristics and consumer perception of 16 Cheonggukjang samples (seven commercial samples and nine samples prepared in the laboratory) were analyzed. Overall, consumer acceptability of Cheonggukjang increased with higher contents of amino nitrogen and volatile basic nitrogen, as well as at lower moisture contents. Cheonggukjang samples with higher consumer acceptability showed higher purchase intent (%) and willingness to pay (won/200 gram package), implying consistency in consumer evaluation. Ideal characteristics of Cheonggukjang were lighter color, less water in the soup, stronger characteristic Cheonggukjang taste, sweetness and nutty taste, as well as less off odors, saltiness, and bitterness. The result of this study demonstrates the needs to improve sensory quality by considering the relatively low consumer acceptability of Cheonggukjang samples.

• Food Science and Preservation
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• v.21 no.5
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• pp.646-651
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• 2014

To evaluate the processing adaptability of burdock (Arctium lappa L) tea, the physicochemical properties of burdock tea treated with steaming and roasting were investigated. The tea treatments included hot-air drying after roasting (HDR, drying at $60^{\circ}C$ for 6 hr), steaming after hot-air drying (SHD, steaming at $100^{\circ}C$ for 10 min), and steaming and then hot-air drying followed by roasting (SHDR, roasting at $250^{\circ}C$ for 3 min). The physicochemical properties, antioxidant activities, and sensory properties of the HDR, SHD, and SHDR teas were measured in hot water, and the tea was extracted from each sample. The color values of lightness (L) and yellowness (b) were lower in the HDR and SHDR teas, and the total sugar content of the SHDR tea was significantly higher than that of the other teas. The ABTS and DPPH radical scavenging abilities of the SHDR tea with a 500 mg% concentration were significantly higher than those of the SHD tea. In the sensory evaluation, the SHDR tea was ranked significantly higher than the other samples as to its color, flavor, taste, and overall acceptability. The results suggest that SHDR can be applied to burdock tea to achieve high quality and functionality.