• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.6
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• pp.775-783
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• 2008

This study was performed to research quality characteristics of yellow layer cakes added with diacylglycerol oil and their effectiveness in reducing trans fatty acids and inhibiting accumulation of fats in the body. The diacylglycerol oil used in this study contained 80% diacylglycerol. In treatments 0, 10, 20, 30 and 40% of the weight of margarine were substituted with diacylglycerol oil. pH and specific gravity of cake batter of treatments increased with more diacylglycerol oil compared to that of the control group. Viscosity of cake batters of treatments also became higher with increasing diacylglycerol oil than that of the control. pH of cakes rose up with increasing amounts of diacylglycerol oil. Volume of cakes became bigger by reducing loss due to water evaporation in a baking process, resulting in a moister texture because of increased moisturizing capacity in oil. In the case of color, the Hunter's colorimetric lightness (L) got higher as the added amount was increased, and redness (a), yellowness (b) and color different ($\Delta$E) got lower against control accordingly. In particular, 30% treatment showed higher levels in the areas of volumes and moisture contents while 20 and 30% treatments were superior in sensory characteristics. Therefore, a yellow layer cake made by substituting 30% of the weight of margarine with diacylglycerol oil was expected to be a low-calorie cake because the oil improves taste and quality of cakes, reduces trans-fatty acids and inhibits accumulation of fats.

• Korean Journal of Food Science and Technology
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• v.21 no.5
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• pp.669-675
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• 1989

Fresh mushroom (Agaricus bisporus L.) was irradiated (0, 1, 2, 3kGy) and kept for 20 days at 9{\pm}1^{\circ}C\;and\;80{\pm}7%$ RH. Parameters of qualities were investigated on the physical and physiological characteristics. The pileus and stipe on nonirradiated mushroom were expanded and elongated from the 3rd day of storage, there by losing the acceptability as edible samples. After 5 days of storage, 2 to 3kGy of gamma irradiation were especially effective for controllong natural maturation and senescence of fresh mushrooms and so irradiated mushrooms were acceptable more than 20days storage. The texture of irradiated samples was superior to that of nonirradiated samples, even though softening of the tissue occurred during storage. Weight loss was greatest in the nonirradiated sample due to evaporation from an increased surface area resulting from expansion and ripending, which were retarded in the 2 to 3kGy irradiated samples after 5days of storage. These results suggest that the irradiation dose of 2 to 3kGy is apparently effective to extend the shelf life of fresh mushrooms stored at the above-mentioned condition.

• Polymer(Korea)
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• v.33 no.1
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• pp.26-32
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• 2009

The aim of this research was to prepare microparticulate systems based on poly (lactide-co-glycolide)(PLGA) for the local release of ipriflavone in order to reduce bone loss. We developed the IP loaded PLGA microspheres using relatively simple oil-in-water(O/W) solvent evaporation method. HPLC was used to perform the in vitro release test of IP and morphology of cell attached on the micro-spheres was investigated using SEM. Cytotoxicity was assayed by cell counting kit-8 (CCK-8) test. Osteogenic differential cells were analyzed by ALP activity. Through RT-PCR analysis, we observed osteocalcin, ALP, and Type I collagen mRNA expression. The release of IP in vitro was more prolonged over 42 days and IP/PLGA microspheres showed the improvement on the cell proliferation, ALP activity and RT-PCR comparing with control (only PLGA). This initial research will be used to direct future work involved in developing this composite injectable bone tissue engineering system.

• Journal of the Korean Society for Nondestructive Testing
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• v.27 no.4
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• pp.345-353
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• 2007

We have obtained a topographical image nondestructively for a Cu thin film in liquid using a near-field scanning microwave microscope (NSMM), its operating frequency was 3.5 to 5.5 GHz. We have kept a distance of 10 nm between tip and sample using a quartz tuning fork shear force feedback system. As an end of tip was attached to one prong of the quartz tuning fork has a length of 2 mm, the only tip of tuning fork was immersed in water tank. A loss cause by evaporation in water tank is regulated with actuator was connected to a supplementary tank. Moreover, using a revise program of LabView, we could increase the accuracy of a measurement in liquid.

• Korean Journal of Food Science and Technology
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• v.32 no.2
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• pp.341-348
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• 2000

Effects of different types of sub-freezing methods on quality of raw pork loin, beef loin and tuna were studied. Storage tests were undertaken as follows; the three different types of sub-freezing methods, such as regular cold chamber at $-1^{\circ}C$, air-blast sub-freezing at $-5^{\circ}C$ and sharp-plate sub-freezing at $-5^{\circ}C$, were evaluated for extending freshness of samples. Pork loin packed with polyethylene-film showed no significant differences (P<0.05) in physico-chemical properties among the above sub-freezing methods. Air-blast sub-freezing methods revealed faster evaporation of moisture from samples. The same sub-freezing method also showed increased VBN values of pork loin and tuna samples. Regular cold chamber resulted in increased TBA values and K values of beef loin and tuna, respectively. It appeared that sharp-plate freezing system kept the food samples with the least loss of freshness among the above three sub-freezing methods. These results indicated that freshness of raw pork, beef and tuna could be significantly extended by the sharp-plate sub-freezing method.

• Korean Chemical Engineering Research
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• v.60 no.4
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• pp.473-477
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• 2022

In this study, candidate technologies for lithium recovery from the process waste liquid generated in the waste battery recycling process were reviewed, and technologies applicable to the process from the commercialization point of view were reviewed from a qualitative point of view. The evaporation method is difficult to apply because it requires a large-scale land and shows a low recovery rate due to the loss of Li during the concentration process. In the case of precipitation, a commercially available technology shows a high recovery rate due to the high Li/Na selectivity of phosphoric acid, but there are disadvantages in that the process is complicated due to the use of expensive phosphoric acid, requiring a recovery step, and continuous operation is impossible because solids are handled in the Li concentration process. In the case of solvent extraction, if we find an inexpensive extractant with high Li/Na selectivity, continuous operation is possible with the method used in extraction of other metals in the previous step, and when Li is concentrated, continuous operation is possible because it is in a liquid state. If it shows a similar recovery rate compared to precipitation technology, commercialization will be the most likely.

• Horticultural Science & Technology
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• v.28 no.4
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• pp.529-534
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• 2010

Occurrence of wilted symptom in watermelon plant ($Citrullus$ $lanatus$ L.) is known to be caused by physiological disorder. The symptom results in the loss of fruit production and thus the economical loss of watermelon growers. The incidence of symptom is often found from the middle of March to the end of May in the major watermelon crop production areas of Korea (i.e. Uiryeong, Gyeongnam (lat $37^{\circ}$56'64"N, long $126^{\circ}$99'97"E)). Despite of extensive information about the physiological disorder, little study has been conducted to understand a relationship between the wilted symptom and accompanying environment factors (e.g. temperature). This study aimed to investigate effects of environmental conditions amended by a forced-ventilation system on physiological characteristics of watermelon and incidence of the wilted symptom. Watermelon plants were grown from January to May, 2009 with either the forced-or natural-ventilation treatment in a greenhouse located in the Uiryeong. In the result, the forced-ventilation treatment decreased the air, leaf and root-zone temperature approximately $4.5^{\circ}C$, $5^{\circ}C$ and $3^{\circ}C$, respectively, compared to the natural-ventilation. The fruit growth rate was maximized twice during the entire growing period. The higher rate of fruit growth was observed under the natural-ventilation than the forced one. Maximization of the fruit growth rate (approximately 430 g per day) was first observed by 12 days after fruiting under the natural-ventilation treatment, while the second one (approximately 350 g per day) was observed by 24 days after fruiting. The wilted symptom started occurring by 22 days after fruiting under the natural-ventilation, whereas no incidence of the symptom was found under the forced-ventilation treatment. Interestingly, the forced-ventilation lowered the fruit growth rate (approximately 320 g per day) compared to the natural one. Maximization of the fruit growth rate under the forced-ventilation was found at 4 days later than that under the natural one. This result coincided with a slower plant growth under the forced-ventilation treatment. These results suggest that the forced-ventilation slows down extension growth of fruit and plant, which may be associated with lowering leaf temperature and saturation deficit. We suggest the hypothesis that the forced-ventilation may alleviate stress of the wilted symptom by avoiding extreme water evaporation from leaves due to high temperature and thus by reducing competition between leaves and fruits for water. More direct and detailed investigations are needed to confirm the effect of the forced ventilation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.3
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• pp.229-235
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• 2001

The thermal and photometric properties of mulching materials modify the radiation and energy balance on the mulched soil surface and thereby change the soil temperature. The soil surface energy balances and soil temperatures under the mulching treatments of non-mulched control, recycled paper (RPM), and black polyethylene film (BPFM) were compared before and after the establishment of potato canopy. On August 30 in 1998 when potato was not emerged yet and solar radiation was 17.9 MJ $m^{-2}$${day}^{-1}$ , the net radiation of the soil surface was estimated as 10.(1, 2. 4, and 1.3 MJ $m^{-2}$${day}^{-1}$ under the control, BPFM, and RPM, respectively. The sensible and latent heat loss from the soil surface was 9.65 MJ $m^{-2}$${day}^{-1}$ in the control, most of the net radiation being lost through evaporation and convection, whereas it amounted only to 1.39 MJ $m^{-2}$${day}^{-1}$ in BPFM and 1.36 MJ $m^{-2}$${day}^{-1}$ in RPM. Therefore, the soil heat fluxes were 0.36 1.02, and 0.06 MJ m$^{-2}$ day$^{-1}$ under the control, BPFM and RPM, respectively. On September 27 when potato canopy was fully developed, the soil surface net radiation in the control was sharply decreased as compared to that of Aug. 30, whereas the net radiation of the mulched soil surfaces showed little changes. The soil heat flux was -0.01, 0.95, and 0.12 MJ $m^{-2}$${day}^{-1}$ at the soil surface under the control, BPFM and RPM, respectively. As the mulching treatments brought about such alteration of energy partitioning into the soil, the highest soil temperature was recorded in BPFM and the lowest in RMP without regard to potato canopy development. However, the soil temperature differences among the treatments become smaller when potato canopy were fully developed.

• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.2
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• pp.59-67
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• 2017

The aim of this experiment was to investigate the effect of air suction rate (SR) during the composting process of swine manure mixed with sawdust used as a bulking agent. In the 25 L composting reactors, the suction rate (SR) was at four different treatment levels (100%, 200%, 300%, 400%), and were fixed on the based on constant aeration rate into the composting mixtures. The temperature reached to thermophilic phase within 2 days and it was maintained up to the $5^{th}$ day of the composting process in all reactors and then gradually decreased to room temperature at the end of the composting process. The moisture content (MC, %) of the initial mixtures was 64.27%, and it was reduced to 38.4, 33.08, 14.59 and 11.93 in the different suction rate of 100%, 200%, 300%, 400%, respectively in the end process. During the composting, the level of pH was increased from 6.83 to 8.67 and it gradually decreased to 7.56 in 100% and 200%(SR). At the same time, the pH values were reduced only up to 8.19 at 300%, and 8.08 at 400%(SR), showing that suction strengths of 100% and 200% were the better option for composting than those of 300% and 400%. The total Kjeldahl nitrogen (TKN) of initial composts mixtures was 2.3% and were changed in 3.3, 3.1, 2.5, and 2.3% at the end of the composting period from the 100%-400% (SR) variations respectively. These results also indicated that 100% and 200% (SR) were more affected by the dry mass loss as $CO_2$ and water evaporation. The initial value of C/N ratio was 25.17 and were significantly reduced to 11.88, 11.97, 14.31, and 14.72 at the end of the experiment, respectively from the 100%-400% (SR) variations. These results suggest that the suction rate (SR) of 100% and 200% relative to constant air supply would be the optimal conditions to produce high-quality compost.

• Korean Journal of Food Science and Technology
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• v.7 no.3
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• pp.128-134
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• 1975

For development of long-term storage method of sweet-persimmons using polyethylene film bags, basic experiment was conducted with 30 boxes of sweet-persimmons in 1973 and the same experiment was extended for industrial application with 2,500 boxes of the persimmons in the cold storage of Jinyoung Sweet-persimmon Association in 1974. Investigation was made on change of the quality by storage period. At the same time, persimmons put in the cold storage test were shipped to market at different time in order to monitor consumer response and commercial feasibility. The followings are conclusion obtained from the result of this experiment. 1. Storage of sweet-persimmon, Buyu, produced in Jinyoung, Kimhae was possible for 1 month at $2^{\circ}C{\pm}1^{\circ}C$ cold storage. This storage period was extended to 4 months until the end of February in case that the fruits were hermetically sealed in P.E. film bags of 0.08 to 0.1 mm thickness. 2. During the storage period of sweet-persimmons packed in the film bags, the loss of weight due to evaporation was effectively prevented with use of the film of bag thicker than 0.04 mm. 3. The storage ability of 3-5 persimmons per small bag was somewhat superior to that of many persimmons packed in the large box of 15kg capacity. 4. The thicker the film of bags, the more $CO_2$ gas was accumulated inside, however, from 1 month after beginning of the storage the rate of $CO_2$ accumulation became very low maintaining the stabilized level of 5-6% at the plot of 0.06-0.08mm thick bags. 5. While the persimmons were in storage, decreased was the content of total sugars, total acids, and vitamin C, of which the phenomenon was remarkable especially with the fruits of non-packed plot. 6. The sweet-persimmons in the film bags subjected to cold storage when shipped to market in their intact condition were more beneficial than when they were shipped out in unpacked condition. The intact fruits packed in the P.E. film bags were able to keep their commercial value for 10days in the outdoor situation. 7. The sweet-persimmons that were packed in the film bags and put in the cold storage had maintained promissing marketability and the economic feasibility was acknowledged when the experimental practice was applied to industrial scale.