• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.439-444
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• 2003

The major factors related in enzymatic hydrolysis of food waste using cellulolytic enzymes of Trichoderma harzianum FJ1 were optimized by response surface analysis. The factors largely affecting to the reducing sugar concentration and enzymatic saccharification rate of food waste such as substrate concentration ($X_1$, %), enzyme concentration ($X_2$, U/ml), and reaction time ($X_3$, hr) were employed. A quadratic polynominal expressing the reducing sugar (RS) concentration relating with the above factors was as follows : RS (g/l) = -17.80 + $5.04X_1$ + $51.37X_2$ + $1.21X_3$ - $0.11X_1\;^2$ - $38.86X_2\;^2$ - $0.03X_3\;^2$ + $1.64X_1X_2$ + $0.04X_1X_3$ - $0.70X_2X_3$ ($R^2$=0.9939). The maximum value of the reducing sugar concentration and saccharification rate were obtained in the conditions of substrate concentration of 18.2%, enzyme concentration of 0.78 U/ml, and reaction time of 19 hr, respectively. The predicated reducing sugar concentration and saccharification rate by the response surface methodology were 95.13 g/l and 47.27%, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.12
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• pp.2004-2011
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• 2013

This study was carried out to investigate the chemical and microbiological properties of Kimchi containing different amounts of squid and octopus during fermentation at $4^{\circ}C$ for 56 days. Kimchi were assigned to one the of the following 7 treatment groups: CK (control Kimchi; no addition), SK-5 (added 5% of squid), SK-10 (added 10% of squid), SK-20 (added 20% of squid), OK-5 (added 5% of octopus), OK-10 (added 10% of octopus), and OK-20 (added 20% of octopus). The quality characteristics of CK and other treatments were determined by measuring the pH, titratable acidity, reducing sugar, volatile basic nitrogen (VBN), and microbial analysis. During fermentation, Kimchi containing squid and octopus had higher pH and lower acidity values than the CK group (P<0.05). The titratable acidity was increased in all treatment groups, whereas the reducing sugar content decreased gradually during fermentation. The reducing sugar contents were highest in the CK group. The VBN value increased in all treatment groups with increasing storage period, and the CK group had lower VBN value than the other treatment groups containing squid and octopus. The numbers of total bacteria and lactic acid bacteria rapidly increased up to the second week, and this slowly increased thereafter.

• Korean Journal of Food Science and Technology
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• v.30 no.2
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• pp.391-396
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• 1998

To inhibit the import of hot sauce, the manufacturing process of the Korean type hot sauce was developed. Chemical analysis of the imported hot sauce showed as follows; moisture 95.66% (w/w), salt 2.79% (w/w), titratable acidity 3.62% (w/w), crude fiber 0.42% (w/w), reducing sugar 0.03% (w/w), capsanthin 0.89% (w/w), capsaicin 4.28 mg% and pH 3.26. Korean type hot sauce prepared with red pepper, salt and vinegar was aged in oak barrel for 12 months at $10^{\circ}C$. Chemical analysis of the Korean type hot sauce showed as follows; moisture 92.05% (w/w), salt 8.82% (w/w), titratable acidity 3.88% (w/w), crude fiber 3.14% (w/w), reducing sugar 1.78% (w/w), capsanthin 0.13% (w/w), capsaicin 2.32 mg% and pH 3.29. Among chemical components, the contents of reducing sugar, salt and crude fiber except capsaicin and capsanthin were more than those of imported one. Chemical components of the Korean type hot sauce were changed slightly during aging for 12 months. The cell counts of yeast were increased from $3.2{\times}10^2\;to\;5.2{\times}10^6$ till the second month and those of lactic acid bacteria were increased from $3.{\times}10^1\;to\;1.5{\times}10^7$ till the third month, those of yeast and lactic acid bacteria decreased from the eighth month showed $6.6{\times}10^4$ and not detectable on the twelfth month, respectively. As the results of sensory evaluation on the Korean type hot sauce were evaluated to be superior to the imported to be superior to the imported one.

• The Korean Journal of Food And Nutrition
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• v.11 no.1
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• pp.1-5
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• 1998

The purpose of this study was to investigate the chemical and sensory properties of Kimchi added apple Juice. Kimchi added amount of 0, 5 and 10% of apple juice was fermented at 4$^{\circ}C$ for 20 days. During the fermentation, pH was lowered in all Kimchi samples and pH of Kimchi added apple juice was a little lower than that of Kimchi without apple juice. Acidity was increased continuously and saltiness was maintained at 1.6~2.3% levels during fermentation. Although reducing sugar was increased in the early stage of fermentation, it was decreased subsequently as fermentation proceeded. Also the reducing sugar of Kimchi added apple juice was relatively higher than the other sample. Total vitamin C(Vit C) of Kimchi added apple juice was reduced in the early stage of fermentation and increased gradually after 10 days. As a result of the sensory evaluation, Kimchi added 5% of apple juice, was showed high scores in taste, flavor, texture and overall acceptability in the early stage of fermentation.

• Korean Chemical Engineering Research
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• v.54 no.3
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• pp.431-435
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• 2016

The aim of this study was to investigate the effect of gamma irradiation on the pretreatment of wood chips with NaOH solution. The degree of saccharification was quantified by measuring reducing sugar and glucose concentrations after enzymatic hydrolysis. After pretreatment with 10 g/L NaOH, the wood chips were irradiated at the doses of 0, 50, 100, and 200 kGy, respectively. Among the irradiated samples, wood chips irradiated at the dose of 200 kGy had the highest reducing sugar concentration of 12.2 g/L. Also, to define the effect of irradiation before pretreatment, the wood chips were first gamma-irradiated and then pretreated with NaOH. When the NaOH treatment was conducted after irradiation at 200 kGy, the reducing sugar content was further increased to 13.4 g/L and glucose content of the wood chip was as high as 7.9 g/L. These results suggest that gamma irradiation may be the promising method for pretreatment of cellulose biomass.

• Food Science and Preservation
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• v.5 no.3
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• pp.217-223
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• 1998

Quality and component of dry Omija during storage and shelf-life of fresh Omija were investigated. Acidity and pH of dry Omija were not significantly different among drying methods, but reducing sugar(3.77%) of field (drying was much lower than that of hot air drying(11.02%) and freeze drying(10.12%). Crude protein was higher in order of freeze drying> hot air drying> field drying, and the optical density of freeze drying at 520nm were higher up to about 3 times than field drying and hot air drying, respectively. Moisture content of dry Omija during the storage was increased, whereas acidity decreased at 25$^{\circ}C$. However changed little at 4, -5, -20$^{\circ}C$ Reducing sugar increased until 8 mouth, and thereafter decreased continuously. Optical density and color(L,a,b) decreased at 25$^{\circ}C$ but increased at 4, -5, -20$^{\circ}C$. Shelf-life of flesh Omija at 4$^{\circ}C$ was limited to 9 days because staring decay. Acidity and reducing sugar of flesh Omija continuously decreased during storage at -5, -60$^{\circ}C$. Optical density increased until 8 month and then decreased, and especially the optical density of 8 month storage at -60$^{\circ}C$ was higher than initial's.

• Food Science and Preservation
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• v.23 no.4
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• pp.510-515
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• 2016

The purpose of study was to evaluate quality, physicochemical and sensory characteristics of acorn Sulgidduk by addition of acorn powder. Acorn Sulgidduk was processed rice powder which added 0, 5, 10, 15, and 20% of acorn powder. The moisture, crude lipid, and crude ash contents of Sulgidduk added with acorn powder was increased by addition amount of acorn powder, but carbohydrate and crude protein contents were decreased. By addition amount of acorn powder, soluble protein content of Sulgidduk were increased, but reducing sugar content were decreased. The L values of Sulgidduk were decreased by addition amount of acorn powder, but increased the a and b values. The hardness, adhesiveness, cohesiveness, springness and chewiness were decreased by addition amount of acorn powder. The sensory test of Sulgidduk added 10% of acorn powder showed the best score in overall preference. Therefore, these results suggested that Sulgidduk added 10% of acorn powder could be applied for produce of acorn Sulgidduk.

• Food Science and Preservation
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• v.22 no.4
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• pp.528-534
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• 2015

This study was performed to analyze the processing and quality characteristics of whey Makgeolli prepared with different types of yeast and ratio of the whey content. Lactose content of yeast culture medium containing S. cerevisiae. was 1.36% whereas lactose content of yeast culture containing K. marxianus KCCM 12015 was very little. Yeast culture of both K. marxianus KCCM 35455 and K. marxianus KCCM 50700 did not produce lactose. Until the 10th day, ethanol production ability of S. cerevisiae, K. marxianus KCCM 12015, K. marxianus KCCM 35455, and K. marxianus KCCM were 0.31%, 2.51%, 2.53%, and 2.59%, respectively. Total acids content increased rapidly with the increase in the addition of whey content in the initial 2 days and then decreased during 4~10 days of fermentation. In the aspect of pH, the pH was rapidly decreased in the initial 2 days and then increased until 10th day of fermentation with the increase in whey content. Ethanol content of whey Makgeollis at 10th day of fermentation was the highest in yeast culture containing K. marxianus. From the sensory evaluation, the flavor score of whey Makgeollisin was higher than that of control. The color and taste scores were increased as the increase in the addition of whey. The comprehensive preference indicated that Makgeolli prepared with 100% whey was the best among other samples.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.1
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• pp.109-116
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• 2016

This study evaluated the effects of low-dose X-ray irradiation treatment on quality characteristics and sensory evaluation of imported navel oranges during storage at $20^{\circ}C$ for 12 days. The samples were irradiated at doses of 0.2, 0.4, 0.6, 0.8, and 1.0 kGy, and changes in color value, hardness, Brix/acid ratio, total sugar content, reducing sugar content, vitamin C content, and sensory evaluation were investigated. There were no significant differences between non-irradiated and irradiated samples in terms of color value, Brix/acid ratio, total sugar content, reducing sugar content, and vitamin C content. Difference in hardness between non-irradiated and irradiated samples decreased at the end of storage. Reducing sugar content was reduced as storage period increased. The sensory evaluation scores of non-irradiated and irradiated samples were not significantly different according to storage period, except for sweetness and texture. Overall acceptability was not significantly different by irradiation dose or storage period. These results suggest that X-ray irradiation does not affect quality characteristics or sensory evaluation.

• Korean Journal of Food Science and Technology
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• v.28 no.4
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• pp.650-656
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• 1996

Quality changes of salted Chinese cabbage with different package pressure and storage temperature were examined during 7-day storage. Each storage yield for 7 days at $0^{\circ}C$ was $87.1{\%}$ in AP (atmospheric pressure) and 83.1% in LP (low pressure). Initial salinity was 2.62 in AP and 2.05 in LP and their changes during the storage were very small. In AP the pH slowly decreased to 5.66 after 7-day storage at $0^{\circ}C$ but rapidly decreased to 4.08 at $20^{\circ}C$. Concentration of reducing sugar in LP was higher than that in AP, as more juice was exuded in LP than in AP. The compression force of salted Chinese cabbage changed slowly at $0^{\circ}C$ and constantly increased at $20^{\circ}C$ during the storage, but decreased in LP. The amount of exuded juice was small in AP but large in LP. Quality changes of salted Chinese cabbage was minimum in AP at $0^{\circ}C$ during the 7-day storage.