• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.7
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• pp.879-884
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• 2009

Allium tuberosum Rotter (Liliaceae, Chinese chives) is a perennial herb of which leaves are used for food. This study investigated the effect of pretreatment on quality of dehydrated Chinese chives. Chinese chives was blanched at $80^{\circ}C$ for 20 sec, followed by drying at $70^{\circ}C$, $80^{\circ}C$, $100^{\circ}C$, or drying at $100^{\circ}C$ for 30 min and subsequent drying at $70^{\circ}C$, or $100^{\circ}C$ for 60 min and subsequent drying at $70^{\circ}C$. Optimum drying temperature and time was $100^{\circ}C$ for 30 min and subsequent drying at $70^{\circ}C$, or $100^{\circ}C$ for 60 min and subsequent drying at $70^{\circ}C$. These conditions were shortened time for dehydration and showed smaller decrease than others in Hunter color L, a, b. Dehydrated Chinese chives showed a constant decrease in greenness with storage, probably due to destruction of chlorophyll by light. In the measurement of Hunter color L, a, b, these conditions showed smaller decrease than others in Hunter color for 15 week storage. Chlorophyll content and SOD (superoxide dismutase)-like activity in that condition was higher than others. It was assumed that a phenolic compound that forms its thermostable activity. The fitness of drying models was conducted in order to explain reducing chlorophyll loss and SOD (superoxide dismutase)-like activity loss. Based upon the chlorophyll content, SOD-like activity, and retention of green color of the vegetable, optimum drying conditions was $100^{\circ}C$ for 30 min followed by $100^{\circ}C$ for 30 min and subsequent drying at $70^{\circ}C$, or $100^{\circ}C$ for 60 min and subsequent drying at $70^{\circ}C$.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 1993.12a
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• pp.6-9
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• 1993

According to changes in population, economic conditions, life-stile and eating habits, the frui ts and vegetables market wi 11 be shi fted from processed (i. e. , canned) to fresh. Undressed fresh produce, consisting of washed, disinfected and peeled fruits and vegetables that either sliced or grated, are currently increased in demand by retail and institutional market which use them as salad components or in ready-to use foods, Main attributes of minimally processed fruits and vegetables are convenience and fresh-like quality. Minimally processed Products readily deteriorate in quality, especially color and texture, as a result of endogeneous enzyme enhanced respiration and microorganisms which lead to reduced shelf Iife. According to changes in population, economic conditions, life-stile and eating habits, the frui ts and vegetables market wi 11 be shi fted from processed (i. e. , canned) to fresh. Undressed fresh produce, consisting of washed, disinfected and peeled fruits and vegetables that either sliced or grated, are currently increased in demand by retail and institutional market which use them as salad components or in ready-to use foods, Main attributes of minimally processed fruits and vegetables are convenience and fresh-like quality. Minimally processed Products readily deteriorate in quality, especially color and texture, as a result of endogeneous enzyme enhanced respiration and microorganisms which lead to reduced shelf Iife. Thus. to prevent these undesirable changes , val'ious techniques such as controlled atmosphere (CA) storage, modified atmosphere OIA) storage, including vacuum packaging have been receiving considerable attention, Although milch research has been done to find optimal conditions for whole intact frui ts and vegetables, only limi ted information is avai lable on fresh cut. and other minimally processed products. 81 iced frui ts exhibi t increas~d ethylene production and respiration compal'ed to whole f, 'uits during distribution in response to tissue damage. As a result, accelerated senescence and enzymatic browning OCCUI', Recent l'esearch on minimally processed fl'uits and vegetables has mainly focused on methods to inhibit browning, due to ban on use of sulfur dioxide, In order to retard or prevent these physiological changes, val'ious al ternatives, reducing agents. acidulants, chelating agents and inol'ganic sal ts have been evaluated for use on fresh cut fl'ui ts. Al though some agents were effective replacement for sulfur dioxide. consum$\textregistered$I'S demandless use of chemical on such products. Shel~ life of minimally processed products has been extended by inhibition of metabolic reactions associated with loss of quality and by inhibition of aerobic spoilage caused by wide variety of microorganisms. Appl ication of ~I.-\ packaging, including vacuum packaging, retards the rate of respiration, prevents growth of aerobic spoilage organisms, inhibits oxidation and color deterioration. Tissue softening is another major problem in minimally processed products because enzymes re 1 a ted to ce 11 wa 11 degrada t i on are not inactivated. Various treatments have been investigated for retardation of the softening of sliced products. Some studies have concentrated on the application of an active packaging system with ~I, l. packaging and calcium infi 1 tration as possible measures to retain firmness of processed products. In my opinion, one important step for production of minimally processed frui ts wi th favorabl e color of cut surface and firm texture is the selection of better cultivar. As the view, changing tendency of fresh color by apple cultivars and relationship between the tendency and PPO activity will be discussed in the seminar. In addition to the topic, research result on quality enhancement of fresh apple slices by heat shock treatment will be introduced.

• The Korean Journal of Food And Nutrition
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• v.22 no.3
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• pp.387-395
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• 2009

This study was conducted to investigate the effects of starch concentrations and heating conditions on the gel characteristics of arrowroot starch. Arrowroot starch gels with various pHs, and starch concentrations, were prepared using different temperatures and heating times, and then stored for 24 hrs at $4^{\circ}C$. The hardness of sample gels made at pH 2.0 and 4.0 increased as the starch concentration increased from 7% to 10%, with the maximum value of 94 N being obtained when the gel was prepared at pH 4.0 with a starch concentration of 10%. The maximum hardness of samples prepared with concentrations of starch ranging from 7~9% appeared at $80^{\circ}C$, regardless of the heating temperature and time. Furthermore, the hardness of samples prepared at greater than $100^{\circ}C$ was relatively lower than that of samples prepared at other temperatures. When a starch concentration of 8% was used, the degree of gelatinization(DR) increased as the heating temperature increased, with the maximum value of DR being about 76% at $120^{\circ}C$, regardless of heating time. After storage for 24 hrs, the hardness of samples prepared at $70^{\circ}C$, $80^{\circ}C$ and $90^{\circ}C$ appeared to decrease, while that of samples prepared at $100^{\circ}C$, $110^{\circ}C$ and $120^{\circ}C$ increased. The correlation between hardness and the degree of gelatinization or retrogradation was very high when samples were prepared at $80^{\circ}C$ with a starch concentration of 9%, as indicated by a correlation coefficient of greater than 0.95. Overall, the microstructures of freeze-dried arrowroot starch gel were composed of a continuous network of amylose and amylopectin with fragmented ghost structures in an excluded phase, but these ghost structures were more evident after storage and with increased heating temperature.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.2
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• pp.296-309
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• 1999

Autopolymerized resin facilitates a more rapid and easier means for the construction of removable orthodontic appliances than heat cured resin. But many reports reveal that more unreacted monomer is found in autopolymerized resin. It is very important to achieve maximum degree of polymerization because if polymerization is inadequate, high level of unreacted monomer has been shown to adversely affect mechanical and physical properties, and also the question of allergy or toxicity to methylmethacrylate must be considered. The purpose of this study was to compare the degree of polymerization according to curing method and curing time. Five groups were desinged ; Group 1 was polymerizied at room temperature($28^{\circ}C$) ; Group 2 in $28^{\circ}C$ water ; Group 3 in $28^{\circ}C$ water under 30psi pressure ; Group 4 in $43^{\circ}C$ water ; Group 5 in $43^{\circ}C$ water under 30psi pressure for 10 minutes, 1 hour 12 hours, 1 day and 3 days. The degree of polymerization was measured by means of Fourier Transform Infrared spectroscopy. The results were as follows: 1. The degree of polymerization increased constantly in accordance with curing time in all groups and after curing for 10 minutes, Group 1 showed significantly higher degree of polymerization after 12 hours and Group 2, Group 3, Group 4, Group 5 after 1 hour(p<0.05). 2. The degree of polymerization decreased in the order of Group 5, Group 4, Group 3, Group 2, Group 1 except when the curing time was 1 hour and 12 hours(p<0.05). 3. The degree of polymerization of Group 4, Group 5 cured at $43^{\circ}C$ showed significantly higher degree of polymerization than Group 2, Group 3 at $28^{\circ}C$ except when the curing time was 1 day(p<0.05). 4. Among Group 2, Group 3 and Group 4, Group 5, the pressure had no effect on polymerization except when the curing time was 12 hours(p<0.05). 5. Between Group 1 and Group 2, the method of storage had no effect on polymerization except when the curing time was 1 hour(p<0.05).

• Journal of Bio-Environment Control
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• v.22 no.2
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• pp.91-99
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• 2013

This research analyzed surplus solar energy in Venlo-type greenhouse using acquired typical meteorological year (TMY) data for designing a heat storage system for the surplus solar energy generated in the greenhouse during the day. In the case of paprika, the region-dependent heating loads for Jeju, Jinju, and Daegwanryong area were approximately 1,107.8 GJ, 1,010.0 GJ, and 3,118.5 GJ, respectively. The surplus solar energy measured in Jeju area was 1,845.4 GJ, Jinju area 1,881.8 GJ, and Daegwanryong area 2,061.8 GJ, with the Daegwanryong area showing 11.7% and 9.6% higher than the Jeju region and Jinju region respectively. In the case of chrysanthemums, regional heating loads were determined as 1,202.5 GJ for the Jeju region, 1,042.0 GJ for the Jinju region, and 3,288.6 GJ for the Daegwanryong region; the regional differences were similar to those for paprika. The recorded surplus solar energy was 1,435.2 GJ, 1,536.2 GJ, and 1,734.6 GJ for Jeju, Jinju, and Daegwanryong region, respectively. The Daegwanryong region recorded heating loads 20.9% and 12.9% higher than in the Jeju and Jinju region, respectively. From the above, it can be said that cultivating paprika, compared to cultivating chrysanthemums, requires less heating energy regardless of the region and tends to yield more surplus solar energy. Moreover, if the Daekwan Pass region is excluded, the surplus solar energy exceeds the energy required for heating. Although the required heating energy differs according to regions and crops, cucumbers were found to require the highest amount, followed by chrysanthemum and paprika. The amount of surplus solar energy was the highest in the case of paprika, followed by cucumber and chrysanthemum.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.4
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• pp.446-454
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• 2008

The traditional Korean drink "Jehotang", which is one of the most commonly prescribed drugs for treatment of the heat stroke accompanied by high fever, severe sweat and thirst, it is effective far quenching thirst strengthening the stomach, stopping diarrhea and regulating intestinal function. It is also known to play a role in activating the growth of useful microbes in the intestine and in multiplying intestinal immune cells. Thus, this study investigated all aspects of the drink in an effort to develop a new functional beverage. In the course of this study, the analytical research into the literature concerning Jehotang an error in the secrets of preparing the drink. The Japanese apricot, which was given the botanical name, "Prunusmume", should only be used with the flesh (scientifically referred to as "Fructusmume"), which is fumigated with straw fire before drying. and the seed should be thrown away. The honey should only be used after it is heated with a gentle fire, before removing the white foam that farms on its surface to make the "Yeonmil". Two kinds of cooking processes were found in the ancient literature. One procedure boiling down the powered Fructus mume mixed with the Yeonmil, while the other procedure involved preparing the Fructus mume's water by adding water to it and blending the water with the Yeonmil and the rest of the raw ingredient before boiling them down. The current procedure, in which the cooking is done in a double boiler, has been widely adopted to its simplicity. The finished Jehotang is put in porcelain, kept at room temperature, and consumed after mixing with cold water.

• Journal of Dental Rehabilitation and Applied Science
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• v.18 no.3
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• pp.157-170
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• 2002

The purpose of this study is to analyze the shear bond strength according to kinds of surface treatment agents and resin cements after acid etching of IPS Empress 2. For this purpose, test groups were classified into silane-treated bonding groups, silica-coated group and Targis link applied group. Then, nine bonding groups in total, each three groups per kind, were prepared by using three kinds of resin cements-Panavia F, Variolink II and Rely-X ARC, and thirty test specimens per group were prepared. To examine any changes in the oral environment, the shear bond strength of each test specimen was measured after dipping test for 24 hours and for five weeks, respectively, in distilled water at $37^{\circ}C$ and performing heat cycle 10,000 times in total, each 2,000 times per week, during a five weeks of dipping, under the condition similar to the oral environment. The bond failure modes were also observed by means of a scanning electron microscope. The results are summarized as follows 1. Statically significant differences between the surface conditioning materials were observed. The shear strength of the silane treatment was the highest of all three types of surface treatments(p<0.001). 2. Shear strengths varied significantly for different types of resin luting agents. But bond strength of Targis link surface treatments were not significantly different(p<0.05). 3. No significant difference of bonding strengths was found between storage time conditions(24 hours and 5 weeks). Only group II, IV, VII, IX were significantly different(p<0.05). 4. After thermocycling, the shear bond strengths of all groups were significantly decreased (p<0.05). Group III, V, VI were no significantly different. 5. On the SEM observation of fractured surfaces, all groups were shown complex failure.

• Journal of Life Science
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• v.15 no.3 s.70
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• pp.439-446
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• 2005

Ferritin is known to be the principle iron-storage protein in a wide variety of rganisms. The electro­phoretic mobility and immunological cross-reactivity of dog splenic ferritin were compared with those of horse, bovine, and pig splenic ferritin after isolation using heat treatment, salting out, column chromatography, and ultrafiltration. These isolation methods allowed the recovery of $\~84{\mu}g$ of the ferritin per g of spleen. The iron content in the dog ferritin was $22.7\%$, which appeared to be higher than those in the other mammalian ferritins tested. The electrophoretic mobility of the dog ferritin under nondenaturing conditions was similar to its bovine counterpart, whereas it was more identical to pig and horse ferritins on an SDS-polyacrylamide gel. The molecular weight of the dog ferritin subunit was 19.5 kDa on an SDS-polyacrylarnide gel, and the subunit was unable to bind with iron. The polyclonal anti-dog ferritin raised in rats was able to cross-react with the pig, bovine, and horse ferritins, upon Ouchterlony double immunodiffusiion. A Western blot analysis also revealed that the anti-dog ferritin, which specifically bound with the dog ferritin subunit, could also recognize the horse, bovine, and pig ferritin subunits and the maximum cross-reactivity was exhibited with the pig ferritin subunit, indicating that the dog ferritin is immunochemically more similar to the pig ferritin than its other mammalian counterparts. Accordingly, these results elucidate the biochemical and immunochemical characteristics of dog ferritin that might have a potential to be applied as an oral iron supplement to treat iron deficiency anemia.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.2
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• pp.166-172
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• 2002

The top shell, Omphalius pfeifferi capenteri meat vacuum-packed in can (diameter$\times$height, 74.1mm$\times$50.7mm) were heated at 115$^{\circ}C$ up to $F_0$ values of 5 min, 10 min, 15 min and 20 min, and the changes in food components were studied. After 14 days storage at 37$^{\circ}C$ and 55$^{\circ}C$, no growth of microorganism and panelling were recognized from the canned meats which were sterlized at 115$^{\circ}C$ with $F_0$ value of S min and over. In the case of proximate composition of the canned meats, the moisture content decreased with the increase of $F_0$ value, while crude protein increased. The increase of volatile basic nitrogen content, pH and degree of browning and the decrease of mineral, total amino acid, free amino acid, trimethylamine oxide, total creatinine contents and yields were observed during thermal processing, In sensory evaluation on color, texture and taste in the canned meats, no significant difference was observed among a boiled sample and the canned meats heated at re value of 10 min and below. But, in the canned meats heated at $F_0$ value of over 15 min, its sensory scores decreased with the increase of $F_0$ value. From these results, the reasonable $F_0$ value for preparation of the heat-treated top shell meats was in the range of 5$\~$10 min.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.5
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• pp.812-821
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• 2008

The characteristics of cold-pressed sesame oil (CPSO), virgin sesame oil (VSO), commercial heat-press extracted sesame oil (CHPESO) and commercial supercritical fluid extracted sesame oil (CSFESO) were investigated. The total phenolics of CPSO, VSO, CHPESO and CSFESO were 31.27, 68.33, 60.65 and 31.44 mg/100 g, respectively. Their $\gamma$-tocopherol contents were 32.82, 31.66, 29.26 and 26.87 mg/100g, respectively. The sesamol, sesamin, and sesamolin contents of VSO were the highest. The oxidation induction period (4.53 hr) of CPSO was lower than that of VSO, CHPESO and CSFESO (19.90, 16.50, and 12.23 hr, respectively). CPSO was rapidly oxidized during storage at $60^{\circ}C$ in the dark, and its peroxide value (POV) was increased about 14 times. Although there were few differences in electron-donating abilities at low concentrations (below 100 mg%), VSO showed the highest electron-donating abilities at higher concentrations (77.76% at 10,000 mg%). Contents of linolenic acid and oleic acid were $40.35{\sim}43.98$ and $31.59{\sim}33.46\;g$/100 g, respectively. CPSO contained the highest amount of oleic and linoleic acid among the variously extracted sesame oil.