• Food Science and Preservation
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• v.18 no.6
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• pp.875-883
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• 2011

Brown rice vinegar was made from brown rice mash with different brewing starter addition rates in static culture, and its quality characteristics were investigated. As a result, the amounts of alcohol produced in the fermentation process were shown to be 9.1, 8.8, 8.6 and 8.5% in the Nuruk 75 : crude enzyme 25 (B), Nuruk 50 : crude enzyme 50 (C), Nuruk 25 : crude enzyme 75 (D) and Nuruk 0 : crude enzyme 100 (E), respectively. The higher the percentage of crude enzyme added was, the lower the alcohol content that was produced. Nuruk 100 : crude enzyme 0 (A) was appeared to contain the lowest alcohol content (7.7%). In addition, the titratable acidity in all the groups was about 0.7%. The final titratable acidity (BV) of brown rice vinegar made with static culture was the highest (approximately 5.2%). The initial pH appeared to be between 3.6~4.0 and steadily decreased as the fermentation progressed, and the pH was almost unchanged after 15 day fermentation. The examination of the changes in the organic acids showed that the acetic acid content was similar in all the groups, and that the single starter added (AV, EV) group had much more other organic acids than the mixed starters added (BV, CV, DV) group. From these results, the mixed starters (Nuruk and crude enzyme) added group appeared to be superior to the single starter added in terms of alcohol production ability and vinegar quality. As the future aging process, however, is expected to change the flavor components and sensory characteristics, studies on various quality factors of vinegar are needed.

• Food Science and Preservation
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• v.19 no.6
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• pp.799-806
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• 2012

This experiment was conducted to establish the optimum conditions for high $CO_2$ gas treatment in combination with a proper gas-permeable packaging film to maintain the quality of fig fruit (Ficus carica L). Among the fig fruits with different high $CO_2$ treatments, the quality change was most effectively controlled during storage in the 70%-$CO_2$-treated fig fruit. Harvested fig fruit was packaged using microperforated oriented polypropylene (MP) film to maintain the optimum gas concentrations in the headspace of packaging for the modified-atmosphere system. MP film had an oxygen transmission rate of about $10,295cm^3/m^2$/day/atm at $25^{\circ}C$. The weight loss, firmness, soluble-solid content (SSC), acidity (pH), skin color (Hunter L, a, b), and decay ratio of the fig fruits were monitored during storage at 5 and $25^{\circ}C$. The results of this study showed that the OPP film, OPP film + 70% $CO_2$, and MP film+70% $CO_2$ were highly effective in reducing the loss rate, firmness and decay occurrence rate of fig fruits that were packaged with them during storage. In the case of using treatments with packages of OPP film and OPP film+70% $CO_2$, however, adverse effects like package bursting or physiological injury of the fig may occur due to the gas pressure or long exposure to $CO_2$. Therefore, the results indicated that MP film containing 70% $CO_2$ can be used as an effective treatment to extend the freshness of fig fruits for storage at a proper low temperature.

• Food Science and Preservation
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• v.17 no.5
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• pp.586-594
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• 2010

We evaluated changes in the microbiological quality and safety of food items (vegetables, seaweed, and processed food) supplied to elementary school food services to evaluate the distribution/delivery system. Pretreated vegetables, seaweed, and processed food were delivered to schools in refrigerated (${\leq}10^{\circ}C$) vans that made several delivery stops before arriving at the schools. During the distribution stage, total plate and coliforms counts were: bellflower roots $7.6{\times}10^5-6.7{\times}10^6$ and $5.8{\times}10^4-5.2{\times}10^5$ CFU/g; blanched bracken $4.5{\times}10^3-2.1{\times}10^5$, $5.0{\times}10^3-1{\times}10^4$ CFU/g; onion $1.2{\times}10^4-1.4{\times}10^4$, $5.0{\times}10$ CFU/g; soybean sprouts $9.6{\times}10^4-6.3{\times}10^7$ and $1.1{\times}10^3-1.2{\times}10^7$ CFU/g; soybean curd < $10-9.7{\times}10^5$ and < $10-2.3{\times}10^5$ CFU/g; and starch jelly < $10-3.8{\times}10^3$ and <10 CFU/g. Bacillus cereus < $10-4.1{\times}10^2$ CFU/g, Escherichia coli $1.0{\times}10-2.0{\times}10$ CFU/g, and Staphylococcus aureus $1.3{\times}10^2-4.1{\times}10^2$ CFU/g were detected on peeled bellflower, whereas B. cereus < $10-4.1{\times}10^2$ CFU/g, Listeria monocytogenes $1.0{\times}10-4.5{\times}10^2$ CFU/g, and S. aureus $1.8{\times}10^2-4.5{\times}10^2$ CFU/g, were detected on soybean sprouts. Most food items were double-wrapped in vinyl and placed in corrugated cardboard boxes prior to delivery, but the boxes, when placed in vans, were not segregated from other food items being delivered to schools and other destinations.

• Food Science and Preservation
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• v.25 no.1
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• pp.36-43
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• 2018

In this study, we investigated the inhibition effect of various herbs on the rancidity of soybean oil. The antioxidant activity of herb-infused oils was evaluated by examining their total phenolic contents and DPPH radical scavenging abilities. The total phenolic contents were found to increase with addition of herbs to the soybean oil. Rosemary-infused oil (RO) exhibited the highest total phenolic contents ($77.28{\mu}g\;GE/mL$), followed by the lemon-balm-infused oil (LO), green-tea-infused oil (GO), and soybean oil (SO) alone (36.82, 36.66, and $21.24{\mu}g\;GE/mL$, respectively). Similary, the DPPH radical scavenging activity of the herb infused oil also increased. Moreover, measurements on the total polar compound (TPC) contents, acid value, and p-anisidine value were carried out in order to confirm the changes in the rancidity of the oils during frying. The time for the TPC content to reach 25% was confirmed to be delayed from 62 h for SO to 68 h, 74 h, and 80 h for GO, RO, LO, respectively. Even though there were some differences between the p-anisidine and acid values, it was confirmed that the addition of herbs inhibited the rancidity of soybean oil. Therefore, the results in this study show that adding herbs to soybean oil could positively contribute to the inhibition of oxidation and rancidity.

• Food Science and Preservation
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• v.25 no.1
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• pp.145-154
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• 2018

The purpose of this study was to investigate the ability of natural antioxidants as stabilizers for meat by-products to prevent lipid oxidation. The white internal organs were evaluated using different treatments: no antioxidant (control), ascorbic acid (T1), Artemisiacapillaris Thunb. (T2), Opuntia (T3), Schisandra chinensis (T4), and Saururuschinensis (Lour.) Baill (T5). Antioxidant activities were analyzed by measuring DPPH contents, superoxide anion radical levels, nitrate scavenging activities, and total polyphenol contents. T1 and T2 showed higher antioxidant activities and total polyphenol contents (p<0.05). Additionally, changes in physicochemical properties (pH, color, volatile basic nitrogen [VBN], and thiobarbituric acid reactive substances [TBARS]) and microbiological aspects in white internal organs processed with antioxidants were investigated. As storage time increased, the CIE $a^*$ and $b^*$ values of the white internal organs processed with natural antioxidants were decreased (p<0.05), and CIE $L^*$ values were low, particularly for the T3 sample relative to that in the control. Moreover, the pH, VBN, and TBARS values of samples T2-T5 were increased after 7 days of storage, but showed low values compared with those of the control (p<0.05). Moreover, compared with the control group, the treatments showed antimicrobial effects. Our results indicated that these natural antioxidants could be used as lipid oxidation stabilizers of meat by-products during storage and that Artemisiacapillaris Thunb. and Opuntia may have applications as natural antioxidants in the meat by-product industry.

• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.2
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• pp.157-161
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• 2011

Although many researches have been carried out concerning the watershed division in natural areas, it has not been researched for the urban watershed division. If the boundary between two urban areas is indistinct because no natural distinction or no administrative division is between the areas, the boundary between the urban areas that have the different outlets (multi-outlet urban watershed) is determined by only designer of sewer system. The suggested urban watershed division model (UWDM) determines the watershed boundary to reduce simultaneously the peak outflows at the outlets of each watershed. Then, the UWDM determines the sewer network to reduce the peak outflow at outlet by determining the pipe connecting directions between the manholes that have the multi-possible pipe connecting directions. In the UWDM, because the modification of the sewer network changes the superposition effect of the runoff hydrographs in sewer pipes, the optimal sewer layout can reduce the peak outflow at outlet, as much as the superposition effects of the hydrographs are reduced. Therefore, the UWDM can optimize the watershed distinction in multi-outlet urban watershed by determining the connecting directions of the boundary-manholes using the genetic algorithm. The suggested model was applied to a multi-outlet urban watershed of 50.3ha, Seoul, Korea, and the watershed division of this model, the peak outflows at two outlets were decreased by approximately 15% for the design rainfall.

• Korean Journal of Soil Science and Fertilizer
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• v.20 no.2
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• pp.185-192
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• 1987

A green house experiment was conducted to find out the acetylene reducing and $N_2$-fixing activity from photosynthetic and aerobic heterotrophic nitrogen fixing microorganisms in submerged paddy soil under different agricultural locality, soil series, soil texture, soil type, and drainage condition in which samples taken from without nitrogen treatment plot of NPK trials on 16 sites of the farmer's field. The results obtained were summarized as follows: 1. The highest acetylene reducing activity was observed at 7 days after incubation in the light condition (photo synthetic microbes+heterotrophic bacteria) while it was observed at 35 days incubation in the dark condition (heterotrophic bacteria). 2. Among the soil series, photosynthetic nitrogen fixing activity was pronounced more in Jangae, Ogcheon and Hwadong series while lower was obtained in Buyong and Daejeong series. Aerobic heterotrophic nitrogen fixing activity was high in Buyong and Daejong series. 3. Estimated amount of $N_2$-fixation from acetylene reducing activity was equivalented to 3.0 mg in light condition and 4.9 mg/100g/105 days in dark condition. 4. Among the agricultural locality, photosynthetic nitrogen fixing activity was high in rather warm southern part while heterotrophic nitrogen fixing activity was predominated more in mountainous area and Chungcheong continental. 5. Photosynthetic nitrogen fixing activity was predominated in high productive soil while aerobic heterotrophic nitrogen fixing activity was pronounced more in crose coarse sandy soil. 6. The soils properties of high photosynthetic nitrogen fixing activity were constituted of poorly or imperfectly drained clay or clay loam soil while heterotrophic nitrogen fixing activity was pronounced more in well to moderately well drained sandy or sandy loam soil.

• Korean Journal of Soil Science and Fertilizer
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• v.20 no.2
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• pp.161-168
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• 1987

This study was conducted to evaluate the effects of potassium and sulfur power levels on the growth, nutrients' uptake at different growing stage and seed yield of peanut plant and changes of soil chamical properties in a sandy peanut cultivated soil of Nak-dong riverside in 1984. 1. The length of main stem, that of branch NO. and NO. of branches per plant were increased by the increased application of potassium and sulfur powdar. Especially sulfur powder treated plot were shown in positive effect with obtained in main root length, NO. of roots and Wt. of noudles formed per plant, roots' weight of peanut plant was much more than top's Wt. at harvesting stage, and so ratio of dry matter Wt. top/root was low. 2. The noudle's Wt. formed was positively significant recognized with dry matter Wt. of peanut plant at harvesting stage and the treatments of potassium were increased 7-20% compared with potassium non-treated plot and sulfur's treatments were increased 4-13% than that of potassium 15kg/10a treatment which was sulfur's non-treated plot in seed yield. 3. Relationship between all nutrients' uptake at flowering stage and seed yield were positively significant recognized, but $P_2O_5$ uptake and N/S ratio showed negative effect at harvesting stage of peanut plant. 4. By the increase of potassium and sulfur powder application, the soil pH at two different stages were almost not differential and the content of K, $P_2O$ and $SO_4$ in soil and $SO_4/P_2O_5$ ratio were increasing tendency.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.6
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• pp.351-356
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• 2006

A long-term experiment was initiated in 1979 at Experiment Farm of Honam Agricultural Research Institute, to investigate the effects of continued use of organic matter (rice straw and compost) along with different levels of nitrogen fertilizer in rice cultivation. The soils of experimental plots is classified as Jeonbug series developed on Fluvio-marine deposits. The application rates of rice straw and compost were 5 Mg/ha/year and 10 Mg/ha/per year, respectively. The fertilizer N application rates per season were 0, 100, 150, 200, and 250 kg/ha. In 2002, after 24 years of experiment, the effect of different treatments on soil pH, characteristics soil organic matter, soil N and P were investigated. The results of the study is summarized as following. The continue use of organic matter tended to lower the soil pH, to increase organic matter and available phosphate contents. The rice straw tended to lower soil pH more than compost, while the effect of compost was greater in increasing soil organic matter and available soil P then rice straw. The application of organic matter resulted in the increase in total organic N in the soil. Such effect was greater in compost application than in rice straw application. In organic N, greatest was amino acid-N, followed by unidentifiable organic N. The least was amino sugar-N. The application of organic matter with and without nitrogen fertilizer affected the in organic fractions of P, particularly Fe-P and Al-P. The application of rice straw tended to increase Ca-P.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.2
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• pp.108-117
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• 2005

Pharmaceutical byproduct sludge and cosmetic industry wastewater sludge can be used as a raw material of compost. Effects of three types of pharmaceutical byproduct sludge and one type of cosmetic industry wastewater sludge on soil properties and red pepper growth were investigated in a field based concrete pot ($2{\times}2m$). These sludges and pig manure ($5Mg\;ha^{-1}$, dry basis) were incorporated into the upper of loam soil 30 days prior to transplanting red pepper. Changes in soil properties and contents of heavy metals and toxic organic compounds in soil and plant were measured. And also plant growth measurement and bioassay of soil phytotoxicity were included. Contents of heavy metals were increased in the soils treated with the sludges. Plant growth in the sludge treatments were mostly inferior to that of NPK treatment, especially in early stage. Content of N in plant was lower in all sludge treatments at early and middle growth stages, and it was especially caused by characteristics and concentration of nitrogen and organic matter of sludges. Total yield of red pepper was highest in the NPK treatment and followed by pharmaceutical sludge 3, pig manure, pharmaceutical sludge 1, and pharmaceutical sludge 2, and the yield of cosmetic sludge treatment was considerably lower than others. HEM and PAHs contents in soil of cosmetic sludge treatment were $4.80mg\;kg^{-1}$ and $2,263.2{\mu}g\;kg^{-1}$, respectively. Root elongation of lettuce exposed to the water extract of soil treated with cosmetic sludge was about 20% of that found in the test with soil extract of non fertilization treatment. At present, raw materials of compost were authorized according to the contents of organic matter, heavy metals and product processing. Toxic organic compounds analysis and bioassay would be helpful for authorization and assessment of suitability of raw materials of compost.