• Korean Journal of Food Science and Technology
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• 제15권2호
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• pp.101-107
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• 1983

The four varieties of Korean soybeans were allowed to undergo natural fermentation for seven days at ambient temperature. The average pH of the product was 3.93 and titratable acidity was 1.94%. For all varieties of soybeans the content of riboflavin increased from 98 to $309.4{\mu}g/100g$ dry-matter, relative nutritive value from 78.66 to 94.59% and available lysine from 6.56 to 7.38 mg/gN, respectively. During fermentation, the activities of protease and lipase increased, while lipoxygenase and trypsin inhibitor activity decreased markedly. The capacity of water sorption of fermented soybean flour was increased with progress of proteolysis during fermentation. The cookie and noodle prepared with 20:80 mixture of fermented soybean flour and wheat flour were in the 'like' category, but it was desirable to neutralize the sour taste produced by fermentation. Among five kinds of products prepared from the fermented soybean flour pan cake was liked most by rural consumers.

• Korean Journal of Food Science and Technology
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• 제45권5호
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• pp.550-556
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• 2013

Reflux extraction properties of Schisandra chinensis were investigated with different extraction conditions of ethanol concentration (0-99%), extraction time (2-8 h), and extraction temperature ($40-100^{\circ}C$). Different chemical properties, such as reducing sugars (RS), titratable acidity (TA), Hunter's color values, total phenolic compounds (TPC), and antioxidant activity (DPPH and ABTS assays) were analyzed for the corresponding extracts. The results showed that RS and TA increased as the extraction temperature increased. For each parameter, the maximum value was achieved, when extraction was carried out with 50% ethanol for 8 h at $100^{\circ}C$. Redness ($a^*$) of the extract decreased as all 3 extraction parameters were increased. TPC increased significantly as the extraction time and temperature increased; further, the highest TPC was achieved, when extraction was carried out with 50% ethanol. The same tendency was observed for DPPH and ABTS radical scavenging activities. The highest TPC and antioxidant activity were obtained, when extraction was carried out with 50% ethanol for 4-6 h at $60-80^{\circ}C$, respectively.

• Horticultural Science & Technology
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• 제30권1호
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• pp.42-49
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• 2012

This experiment was conducted to find out the effects of nitrous oxide ($N_2O$) on the postharvest quality of 'Janghowon hwangdo' peach fruits. Fruits were harvested at commercial maturity for marketing in late September, and treated with 70% $N_2O$ + 20% $O_2$ + 10% air, 80% $N_2O$ + 20% $O_2$, and 90% $N_2O$ + 10% $O_2$ for 48 h, and then stored at $15^{\circ}C$. No significant treatments for soluble sugar and titratable acidity contents were detected. However, good appearance and taste in peach fruit were maintained better in 80% $N_2O$ treatment than in air treatment. The treatment with 90% $N_2O$ had negative effects on weight loss and taste because of rotting by anaerobic fermentation. 80% $N_2O$ treated fruit had significantly higher fungus (Botrytis cinerea) growth inhibition of saprogenic approximately than air treatment until 12 days of storage. The browning and rotting at surface of peach were also retarded when peaches were treated with 80% $N_2O$ before they were artificially wounded. The activity of polyphenol oxidase (PPO) was inhibited about 80% in peach of 80% $N_2O$ treatment compared with in air treatment. The result showed that 80% $N_2O$ treatment was able to extend the shelf life of peach fruits through maintaining taste and inhibition of softening and browning by rotting and wounding during storage.

• Food Science and Preservation
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• 제20권6호
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• pp.784-790
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• 2013

The quality characteristics of Campbell grape juice with different extraction processes (AE; autoclave extraction, HWE: hot water extraction, and EE: enzyme extraction) were investigated. The juice yields of the AE, HWE, and EE juices were 79.8%, 82.3% and 92.6%, respectively. The titratable acidity and soluble solids of the EE juice were significantly higher than those of the other extracts. There was no significant difference in the $L^*$ values of the juices, but the $a^*$ and $b^*$ values of the EE juice were higher than those of the other extracts. The viscosity of the HWE and EE juices was higher than that of the AE juice. The major free sugars in the grape juice were identified as glucose and fructose, and the highest organic acid content was found in the EE juice. The total polyphenol content of the EE juice was 55.7 mg% and was higher than those of the AE and HWE juices, which were 31.3 mg% and 39.5 mg%, respectively. Especially, the anthocyanin content of the EE juice was 22.1 mg%, which was two to four times higher than those of the AE and HWE juices, which were 4.5 mg% and 10.5 mg%, respectively. The EE juice showed the highest antioxidant effect, measured from the DPPH free radical scavenging activity and reducing power. In conclusion, we suggest that the enzyme treatment in the grape extraction was more effective than the autoclave and hot water methods.

• Korean Journal of Microbiology
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• 제49권4호
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• pp.403-414
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• 2013

This study evaluated the physicochemical and microbiological characteristics and antioxidant properties of yogurt samples fermented with lactic acid bacteria (LAB) obtained from pickled cabbage. API 50 CHL systems and 16S rRNA nucleotide sequence analyses revealed that the isolates were Lactobacillus casei PC05 and L. acidophilus PC16. Cell counts, titratable acidity, and viscosity of the yogurt samples fermented with L. acidophilus PC16 were significantly higher than those of the samples fermented with L. casei PC05 (P<0.05). The detected cell counts and physicochemical properties were significantly lower in plain yogurt than in soy yogurt (P<0.05). Yogurt samples fermented with L. acidophilus PC16 exhibited higher antioxidant activity, measured as ability to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and chelate ferrous ions, than those fermented with L. casei PC05. However, the ability to scavenge superoxide anions and superoxide dismutase (SOD) activity were significantly (P<0.05) higher in yogurt samples fermented with L. casei PC05 compared to those in samples fermented with L. acidophilus PC16. The antioxidant activity of soy yogurt was significantly (P<0.05) higher than that of plain yogurt. The antioxidant activity of the tested strains resulted in lipid peroxidation inhibition (in vitro), which may be related to the elimination of free radicals, chelating ability, and reducing power. There were no significant differences in the physicochemical properties and antioxidant activities of the yogurt samples during cold storage.

• Microbiology and Biotechnology Letters
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• 제44권2호
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• pp.109-116
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• 2016

A test meju (meju 1) was prepared by inoculating two strains of Bacillus amyloliquefaciens (EMD17, MJ1-4), Pichia farinosa SY80, and Rhizopus oryzae into cooked soybeans. A control (meju 2) was prepared by inoculating Bacillus subtilis KACC16450 and Aspergillus oryzae. Another control (meju 3) was prepared using rice straw as the source of microorganisms. Three different mejus were fermented for 56 days outdoors. Meju 1 and meju 2 showed higher pH values than meju 3, whereas meju 3 showed higher titratable acidity than meju 1 and meju 2. Meju 1 showed the highest fibrinolytic activity. Bacillus cereus was not detected in any mejus, but various microorganisms were detected in meju 2 and 3. Histamine was detected in meju 2 and tyramine in meju 3 at lower concentration, which were not detected in meju 1. It was concluded that microbially safe, fermented soybean products could be produced from meju fermented with starters such as B. amyloliquefaciens EMD17 and B. amyloliquefaciens MJ1-4.

• Journal of the Korean Society of Food Science and Nutrition
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• 제45권2호
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• pp.202-208
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• 2016

The physicochemical properties and antioxidant activities of fermented mulberry by lactic acid bacteria were investigated. The viable cell counts of lactic acid bacteria slowly increased up to 8.31 log CFU/mL. The pH and titratable acidity were 3.90 and 0.15%, respectively, after 24 h of fermentation. Color in terms of L and a values decreased, whereas b and ${\Delta}E$ values increased. The total anthocyanin contents of fermented mulberry (171.40 mg/100 g) was higher than that of mulberry (144.70 mg/100 g). The cyanidin-3-glucoside and cyanidin-3-rutinoside contents of fermented mulberry were 61.39 mg/100 g and 85.45 mg/100 g, respectively. Total phenolic and flavonoid contents of fermented mulberry (10.75 g/100 g and 5.02 g/100 g, respectively) was higher than those of mulberry (4.53 g/100 g and 1.77 g/100 g, respectively). The oxygen radical absorbance capacity of fermented mulberry was $292.94{\mu}M/g$. The 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity and superoxide radical scavenging activity of fermented mulberry at $250{\sim}2,500{\mu}g/mL$ were 17.40~58.21% and 32.63~87.34%, respectively. The ferric reducing antioxidant power and reducing power of fermented mulberry at $250{\sim}2,500{\mu}g/mL$ were $37.03{\sim}762.13{\mu}M$ and 0.12~0.74, respectively. The results suggest that mulberry fermented by lactic acid bacteria has potential as functional materials in food industry.

• Food Science and Preservation
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• 제9권3호
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• pp.315-320
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• 2002

In order to improve some problems such as contamination of undesirable mold, mycotoxin production and excessive drying on the surface of traditional meju. Control meju without koji and capsule type meju(CM) coated with soybean mixture containing 0.5%, 1% and 2%(w/w) R. oligosporus koji were dried at room temperature (10∼15$^{\circ}C$) for 3 days. Control meju I was fermented in outdoor for 27 days. Control meju IIand CMs were fermented in Korean yellow clay room at 25$^{\circ}C$ for 7 days under 80% relative humidity as first step, and then fermented in outdoor (average temp. 2.7$^{\circ}C$, December) for 20 days as second step. The moisture content of CMs were higher than that of control meju I to the range of 2.88∼7.55%(w/w). pH and titratable acidity in CMs were similar to control group. Amino type nitrogen content in CMs(800.80, 816.0, 901.60 mg%) were 2.2∼2.6 times higher than that in control meju I (347.2 mg%). Reducing sugar content in CMs(2.78∼3.13%) was similar to control meiu I (2.10%) and control meju H(2.31%). Lightness(L) value of control meju I was higher than that of control meju IIand CMs.

• Food Science and Preservation
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• 제12권6호
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• pp.540-545
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• 2005

This study was conducted to evaluate the efficacy of high a)z pre-treatment (60, $100\%$ for 3, 6, 12 hr) on quality of 'Hikawa Hakuho' peach fruits. High a)z treatment inhibited the respiration and ethylene production, especially with long tenn treatment for more than 6 hr. Discoloration of peel, softening and decay were reduced by high $CO_2$ treatment $CO_2$ concentration of $60\~100\%$ did not affect soluble solids content and titratable acidity of fruits. $CO_2$ treated fruits, however, showed higher sweetness score compared with control. As the $CO_2$ concentration and treatment duration increased from 60 to $100\%$ and from 3 to 12 hr, respectively, the efficacy on quality increased. Fruits treated with $100\%\;CO_2$ for 3 hr and $60\%\;CO_2$ for 12 hr, however, showed very low flavor score due to the residual $CO_2$ in flesh. High $CO_2$ injury was not noted at any $CO_2$ levels tested in this study. Above results suggest that $60\%\;CO_2$ treatment for 6 hr resulted in as good control of respiration, ethylene production, decay, discoloration and softening without off-order.

• Applied Biological Chemistry
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• 제50권4호
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• pp.287-294
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• 2007

Effect of combined use of anti-microbial materials, such as ethanol, mustard and chitosan, on the quality of low salted kochujang was investigated during fermentation at $20^{\circ}C$ for 12 weeks. Viable cells of yeast increased remarkably during fermentation, but increasing ratio was significantly low in ethanol-mustard added kochujang. Activity of ${\beta}-amylase$ was high in anti-microbial material added kochujang, whereas ${\alpha}-amylase$ and protease activities were low in those groups. Water activity decreased during fermentation with being low in the control kochujang prepared with normal-salt without anti-microbial materials. Hunter L-, a- and b-values of kochujang increased during fermentation, and the degree of increase in total color difference $({\Delta}E)$ was low in ethanol added kochujang. Titratable acidity of kochujang was decreased in anti-microbial materials added group at late aging period, and oxidation-reduction potential was low in the control kochujang. Total sugar and reducing sugar contents of kochujang were high in ethanol-mustard added kochujang. Ethanol contents of kochujang increased at late aging period, with high values in ethanol-chitosan added kochujang. Amino nitrogen content increased during middle of fermentation, and ammonia nitrogen content of kochujang decreased in ethanol-mustard-chitosan added group during fermentation. After 12 weeks fermentation, sensory results showed that ethanol or ethanol-mustard added kochujang were the highest in color and flavor with the highest overall acceptability.