• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.215-221
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• 2006

This study focuses on investigating the effect of porosity-controlled earthenware on fermentation of kanjang, Korean soy sauce. Porosity of fermentation vessel was controlled by changing the mixing ratio of raw soils at manufacturing earthenware. Earthenwares contented 0%, 40% and 60% of the mixture of red brown soil and powdered soil (1 : 1), respectively. The more contents of the mixed soil, the more porosity in earthenware. During fermentation of kanjang in porosity-controlled earthenwares at $30^{\circ}C$ for 4 months, physical, chemical, microbiological and sensory quality attributes were monitored. Compared to other containers, kanjang in the earthenware that had 0% mixed soil showed less water loss, salt content and pH. It also produced higher total acidity, protease activity, total nucleotide, and microbiological changes which included total aerobic bacteria, lactic acid bacteria and yeast. Total nitrogen and free amino acids in kanjang did not show the consistency with the mixed soil contents of fermentation containers, which may take more effect of other factors as water loss than the porosity of vessels. However, the percentage of glutamic acid in total free amino acids was a little higher in the earthenware that had 0% of mixed soil than other containers. These positive physicochemical, microbiological changes also resulted in higher sensory quality.

• Korean Journal of Food Science and Technology
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• v.44 no.1
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• pp.69-75
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• 2012

To investigate the effects of soybean germination time on the quality of cheonggukjang, the physicochemical characteristics and enzyme activities of cheonggukjang during fermentation were compared. B. subtilis SCD 115035 strain isolated from traditional cheonggukjang was selected for making cheonggukjang. Germinated (12-h) soybeancheonggukjang produced the highest amount of viscous substance (13.22%) after 48 h of fermentation, and the contents were inversely proportional to the germination time of the soybeans. The acidic- and neutral-protease activities of ungerminated soybean-cheonggukjang were higher than those of germinated soybean-cheonggukjang. The amino nitrogen content of ungerminated soybean-cheonggukjang was the highest (436.93 mg%) at 48 h of fermentation, and its content was similar to that of 12-h germinated soybean-cheonggukjang. However, the total isoflavone content of 36-h germinated soybean-cheonggukjang was the highest after 72 h of fermentation, and its content was higher than those of cheonggukjang made from soybeans germinated for 0, 12, and 24 h.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.5
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• pp.736-742
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• 2013

The physiochemical properties of commercial fruit vinegars were compared according to fermentation methods. Type A vinegars were synthesized through acetic acid fermentation while Type B vinegars were produced using both alcohol and acetic acid fermentation serially. There were differences from using these fermentation methods; Type A vinegars had a lower pH and slightly higher total acidity than Type B vinegars. The content of total sugar and reducing sugar were relatively higher in Type B vinegars, which showed a higher content of the free sugars (fructose, glucose, sucrose, and maltose). The intensity of brown color and Hunter's a and b values were also high in Type B vinegars. In contrast, the content of organic acids was higher in Type A vinegars, which were mainly composed of acetic, tartaric, malic, and succinic acid. We were also able to estimate the fruit juice content of vinegars through its content of organic acids. Type B vinegars contained a higher total phenolics and flavonoids content than Type A vinegars, and showed a higher DPPH radical scavenging activity.

• Magazine of the Korean Society of Agricultural Engineers
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• v.35 no.2
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• pp.92-103
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• 1993

A sunday system with a horizontal bin-type composter was constructed and operated to evaluate its composting performance for four days for each test in October, 1992. A sundry system is one of popular systems for composting livestock manure, of which main benefit is to utilize unlimited, clean, and free solar radiation. A rectangular concrete bin(composter) with dimension of 300cm(length) X90cm(width) X60cm(height) was bedded alternatively with four lanes of aeration pipes and heating pipes, and was insulated at three walls with 50mm styrofoam. Each aeration pipe of a diameter of 25mm had 4mm perforated holes at every 15cm longitudinally, and supplied air of about 2m$^3$/min to the composter to maintain aerobic condition . A stirrer rotating at 1 rpm made one round trip every 20 minutes on the conveying chain along the the length of the composter. Five tests (Test 1~Test 5) were implemented to evaluate the composting effectiveness of a sundry system with a horizontal bin-type composter. Treatments of two levels of the mixture ratio of swine manure and paper sludge cakes(manure : paper sludge cakes= 1 : 4 and 1 : 2) and two levels of the water content(W/C ; 70% and 50%) were made to test the significance of the physicochemical properties for decomposition of the mixture materials. Temperature, C/N ratio, water content, microbial activity of the composting materials were taken measurements to evaluate its performance with the lapse of composting time for tests. A small-scale sundry system with a bin-type composter did not appear to be an appropriate system for composting livestock manure. Since heat generation by the composting materials could not overcome heat loss due to areation in a small-scale composter, a proper thermal enviroment could not be maintained to propagate massively thermopilic microorganism relatively in a short period of time. Different from the result of Chol et al.(1992) 6), a temperature variation of the composting materials did not show the peak clearly and C/N ratio didn't lower with time as expected. Mesophilic microoragnism seemed to play an important role for decomposition of the mixture materials. A sundry system with a bin-type composter may be good for a large-scale livestock farm household which may produce enough animal manure. Therefore a decision should be made very carefully to choose a system for composting livestock waste.

• Korean Journal of Food Science and Technology
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• v.45 no.1
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• pp.53-58
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• 2013

The effect of baking on the physicochemical and sensory properties was investigated using a model system of sponge cakes incorporated with pine leaf powder (PLP) as a value-added food ingredient. PLP was incorporated into cake batter at 5 levels (0, 2, 4, 6, and 8%, w/w) by adding an equivalent amount based on the weight of wheat flour. After appropriate mixing, sponge cakes were baked at $170^{\circ}C$ for 30 min in an oven. The baked cakes were cooled to room temperature for 1 h prior to all measurements. The pH, moisture content, specific volume, height, volume index, and symmetry index decreased significantly with the increase in PLP content (p<0.05). On the contrary, specific gravity of the batter and baking loss increased (p<0.05). The lightness of the cakes decreased, whereas redness increased significantly with the higher amount of PLP in the formulation (p<0.05). Hardness also increased significantly (p<0.05). Both total polyphenol content and DPPH (1,1-diphenyl-2-picryl hydrazyl) radical scavenging activity increased significantly by the addition of PLP (p<0.05). The consumer acceptance test indicated that the addition of PLP up to 4% did not cause a significant unfavorable effect on the consumer acceptances in all attributes. The sponge cakes with 2-4% PLP would be recommended with respect to the overall acceptance score while taking advantage of the functional properties of PLP without sacrificing the consumer acceptability.

• Korean Journal of Food Science and Technology
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• v.48 no.5
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• pp.486-491
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• 2016

Efficacy of dielectric barrier discharge-cold plasma treatment (DBD-CPT) for microbial decontamination of onion powder was evaluated. Onion powder, inoculated with Escherichia coli O157:H7, Salmonella Enteritidis, or Listeria monocytogenes, was treated with helium DBD-CPT. DBD-CPT (9 kV, 20 min) inhibited E. coli O157:H7, S. Enteritidis, and L. monocytogenes by $1.4{\pm}0.5$, $2.3{\pm}0.3$, and $1.2{\pm}0.0log\;CFU/cm^2$, respectively. The inactivation levels of E. coli O157:H7, S. Enteritidis and L. monocytogenes increased by $2.2{\pm}0.1$, $2.5{\pm}0.1$ and $1.9{\pm}0.3log\;CFU/cm^2$, respectively, as water activity increased from 0.4 to 0.8, and increased by $2.3{\pm}0.4$, $2.1{\pm}0.1$ and $1.6{\pm}0.1log\;CFU/cm^2$, respectively, as the particle size increased from 0.3 to $1.0cm^2$. Neither the ascorbic acid and quercetin concentrations nor the color of onion powder was changed by DBD-CPT (p>0.05). These results demonstrate the potential for application of DBD-CPT in improving microbiological safety of onion powder while preserving the physicochemical properties.

• Korean Journal of Food Science and Technology
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• v.49 no.4
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• pp.421-429
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• 2017

In this study, we investigated the effect of roasting temperature on nutrient content, digestive enzyme activities, and antioxidative properties of sesame seed juice. The sesame seeds were either roasted at 160, 200, and $240^{\circ}C$ or not roasted, and the juice was extracted using a low-speed juice extractor. Owing to the short duration of roasting, benzo[a]pyrene were not detected and trans fatty acids were negligible detected in all sesame seed juices. The sesame seed juice contained abundant nutrients such as minerals, vitamins, and fatty acids. The contents of minerals, vitamin B1 and B3, and sesamol increased with increase in roasting temperature; however, the levels of fatty acids, vitamin B2, sesamin, and sesamolin decreased. In addition, the antioxidant content and antioxidative activities of sesame seed juice increased with increase in roasting temperature. Therefore, these results suggest that roasted sesame seed juice possesses high antioxidative activities, which may be beneficial for preventing oxidative damage in the body.

• Korean Journal of Food Science and Technology
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• v.50 no.3
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• pp.339-343
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• 2018

Effects of different drying processes, such as hot air drying (HA), superheated steam with hot air drying (SHS/HA), and superheated steam with far infrared radiation (SHS/FIR), on the properties of cherry tomatoes (Solanum lycopersicum var. cerasiforme) were studied. Characteristics of dried cherry tomatoes were determined by examining the water content, internal microstructure, and rehydration capacity under different drying processes. Moreover, ascorbic acid (AA) and lycopene levels were also measured to evaluate thermal damage caused by drying. Cherry tomatoes dried using both SHS/HA and SHS/FIR had water content and water activity similar to those of intermediate moisture food, indicating partial dehydration after combined drying processes. Although AA and lycopene levels decreased drastically after drying, tomatoes dried using SHS/FIR showed the lowest losses of AA and lycopene among samples. Cherry tomatoes dried using SHS/FIR showed a less compact internal cell structure than that of cherry tomatoes dried using HA and SHS/HA, resulting in the highest rehydration capacity. These results suggest that a combined drying process such as SHS/FIR is more effective than conventional hot air drying for the production of partially dried cherry tomatoes with improved quality attributes.

• Journal of the Korean Society of Food Culture
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• v.20 no.3
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• pp.346-351
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• 2005

The physiochemical characteristics and sensory properties of Jinyang-ju was investigated on pH, total acidity, alcohol content, conductivity, dissolved solid, turbidity, reducing sugar content and sensory evaluation. Glutinous rice starter showed the enzyme activity that the ${\alpha}-amylase$ was 121.0 unit, ${\beta}-amylase$ was 40.0 unit and acidic. neutrality protease were 34.2, 23.7 unit, while the nonglutinous rice starter showed ${\alpha}-amylase$ was 156.0 unit, ${\beta}-amylase$ was 45.2 unit, acidic neutrality protease were 9.06, and 0.1 unit, respectively. The pH of the glutinous rice Jinyang-ju and nonglutinous rice Jinyang-ju showed the value of 5.33 and 4.04, total acidity of 2.30% and 2.05%, alcohol(%) of $2.58{\sim}13.5%\;and\;2.51{\sim}15.5%$, total organic acid content(mg%) of 4.35 and 7.63, free sugar of 4.98 mg% and 2.90 mg%, respectively. The sensory evaluation showed that the glutinous rice Jinyang-ju was more acceptable value than nonglutinous rice Jinyang-ju.

• Journal of agriculture & life science
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• v.46 no.5
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• pp.91-100
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• 2012

Physicochemical and antimicrobial activities of 12 different garlic cultivars were investigated. Width and weight of California late cultivar (60.44mm, 53.73g) was the biggest and heaviest but Changyoung cultivar (44.04mm, 25.15g) was the smallest and lightest among the variety of garlic. The range of L, a and b color characteristics of garlic surface from different variety were 84.13~90.56, -1.10~0.77 and 18.24~26.61, respectively. Shear force was the lowest in California early, but 94-12-2 cultivar ($4211.35cm/kg^2$) was higher than another cultivars. Soluble solid range was 6.40~11.33 %brix, and Changyoung cultivar was the highest than the others, significantly. pH of garlics from different cultivar were 5.57~6.53. Total thiosulfinate content of California late cultivar (146.05mM/g) was higher, but Italy cultivar (93.23mM/g) was lower than the others. Total pyruvate content was the highest in Yugo cultivar ($162.50{\mu}M/g$) and the lowest in California early cultivar ($147.41{\mu}M/g$).