• Applied Biological Chemistry
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• v.13 no.3
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• pp.207-218
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• 1970

Studies were carried out to develope the most economical and practical methods of packaging and preservation of kimchi, so commercialization of kimchi manufacture could proceed rapidly. The results obtained may be summarized as following. (1) It is generally established that the acceptable range of lactic acid content of kimchi is between 0.4% and 0.75%. Based on sensory evaluation, kimchi having lactic acid content below 0.4% and above 0.75% was not edible, and the time of optimum taste corresponded to the vicinity of 0.5% of lactic acid content. For the refrigeration storage with or without preservatives, the packaging kimchi in plastic film must be done at the lactic acid content of 0.45%, for lactic acid fermentation will continue slowly after the packaging. However, for the heat sterilized kimchi the packaging should be done at the 0.5% of lactic acid content for the best because lactic acid fermentation is completely stopped after the packaging. (2) Polyethylene, polypropylene, and polycello were chosen as suitable packaging materials. Polyethylene is cheapest among them but kimchi packaged in this film was damaged frequently in handling process and gave off kimchi flavor. On the other hand polypropylene also gave off kimchi flavor, but its higher mechanical strength gave better protection to kimchi and it had superior display effect due to the transparancy. Therefore polypropylene made much better packaging material. Polycello proved to be the best packaging material from the standpoint of physical characteristics but its price is higher than that of other plastic films. To be effective, the thickness of plastic films for packaging kimchi must exceed 0.08mm. (3) Keeping property of kimchi appeared to be excellent by means of freezing. However, by the time the frozen kimchi was thawed out at room temperature, moisture loss due to drip was extensive, rendering the kimchi too stringy. (4) Preservation of kimchi at refrigerated temperatures proved to be the best method and under the refrigerated condition the kimchi remained fresh as long as 3 months. The best results were obtained when kimchi was held at $0^{\circ}C$. (5) In general, preservatives alone were not too elective in preserving kimchi. Among them potassium sorbate appeared to be most effective with the four fold extension of self-life at $20^{\circ}C$ and two fold extension at $30^{\circ}C$. (6) In heat sterilization the thickness of packaged kimchi product had a geat effect upon the rate of heat penetration. When the thickness ranged from 1.5 to 1.8cm, the kimchi in such package could be sterilized at $65^{\circ}C$ for 20 minutes. Kimchi so heat treated could be kept at room temperature as long as one month without apparent changes in quality. (7) Among combination methods, preservation at refrigerated and heat sterilization could be favorably combined. When kimchi was stored at $4^{\circ}C$ after being sterilized at $65^{\circ}C$ for 20 minutes, it was possible to preserve the kimchi for more than 4 months.

• The Korean Journal of Mycology
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• v.17 no.3
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• pp.124-131
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• 1989

Some factors effecting on mycelial growth and cultural substrates using pine sawdust were investigated to develop an artificial cultivation technique. The optimal temperature and media pH for the mycelial growth were at $25^{\circ}C$ and 4.0, respectively. The mycelial growth was not different among three isolates tested. Among them ASI 19003 isolate showed the highest mycelial density and fruitbody yield. Among supplements added into pine sawdust, wheat bran was the best and its appropriate percentage was 20 for the mycelial growth. The mycelial densities were uprisen according to the amounts of the supplement. The highest yield, 107g/bottle of the sporophores of the mushroom was obtained from the substrates supplemented by 30% of wheat bran, but no fruitbody was formed on non supplemented one. Optimal moisture contents of the substrates was different for the mycelial growth, pinheading and fruitbody yields. Sixty five, 60 and 75% of moisture contents of the substrates were optimal for the mycelial growth, pinheading and fruitbody yields, respectively.

• The Korean Journal of Mycology
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• v.2 no.1
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• pp.1-6
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• 1974

1. The mycelial growth and sporulation of Mycogone perniciosa was compared on modified Czapek's media deficient in carbon source, nitrogen source, K,Mg, P or the heavy metal elements. The mycelial growth was significantly reduced in solution cultures lacking Mg, K or P and only a trace of growth occurred in solutions lacking carbon source or nitrogen source. Most sparse sporulation and smaller chlamydospores than on any of deficient agar media occurred on agar media dificient in carbon source or nitrogen source. 2. In both potato dextrose agar and malt extract solution, growth of the fungus was optimum at $25^{\circ}C$, and undetectable at $10^{\circ}C$ and $35^{\circ}C$. 3. Optimum pH for growth of this fungus was 7.0. 4. This fungus was killed in soil when exposed to $50^{\circ}C$ or higher for 20 minutes or more.

• Clean Technology
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• v.19 no.3
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• pp.264-271
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• 2013

In this study, we optimized the removal condition of contaminants attached on the scrap surface to recycle the scrap generated from the Zr alloy tube manufacturing process back to the nuclear grade. The main contaminant is remnant of watersoluble cooling lubricant that is used in the pilgering manufacture during the tube production, and it is assumed to be compressed and carbonized on the surface of tube. Zirlo alloy tube of ${\phi}9.50mm$, which has high occurrence frequency of scrap, was selected as the object to be cleaned, and cleaning abilities of reagents were evaluated by measuring the characteristics of contaminants remained and by analyzing the surface of the tube after cleaning process. For evaluation of each cleaning agent, we selected two types of sodium hydroxide series and three types of potassium hydroxide series. Furthermore, to confirm dependence on tempe-rature and ultrasonic intensities, cleaning at the room temperature, $40^{\circ}C$, and $60^{\circ}C$ was conducted, and results showed that higher the cleaning temperature and higher the ultrasonic intensity, better the cleaning effect. As a result of the bare-eye inspection, while the use of sodium hydroxide provided satisfactory condition on the tube surface, the use of potassium hydroxide series provided satisfactory condition on the tube surface only when the ultrasonic intensity was over 120 W. In the cleaning effect analysis using the gravimetric method, cleaning efficiency of sodium hydroxide series was as high as 97.6% ($60^{\circ}C$, 120 W), but since the tube surface condition was poor after the use of potassium hydroxide, the gravimetric method was not appropriate. In the analytical result of surface contaminants on the tube surface, C, O, Ca, and Zr were detected, and mainly C and O dominated the proportion of contaminants. It was also found that the degree of cleaning on the tube affected the componential ratio of C and O; if the degree of cleaning is high, or if cleaning is well-conducted, the proportion of C is decreased, and the proportion of O is increased. Based on these results, optimal cleaning for application in the industry can be expected by categorizing cleaning process into three steps of Alkali cleaning, Rinsing, and Drying and by adjusting cleaning parameters in each step.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.317-323
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• 1994

Nine plant foods (persimmon leaf, perilla seed, Chinese quince, ginger root, walnut, mugwort leaf, arrowroot, buckwheat and sorghum) rich in phenolic substances were examined for their effects on the digestive enzymes, food-poisoning bacteria and mutagenicity/antimutagenicity by Ames test. Among tested samples, Chinese quince significantly inhibited the $\alpha-amylase$ activity (97%), exhibiting an uncompetitive inhibition type. Protease activity was inhibited by Chinese quince (86%), persimmon leaf (51%) and mugwort leaf (20%), in which mugwort extract exhibited a noncompetitive type. Lipase was activated >50% by all samples. The inhibition of $\alpha-amylase$ was highly correlated with the content of condensed tannin (r=0.89) and the inhibition of protease, with total phenolic content (r=0.84). Total phenolies fraction of tested samples showed the growth inhibition toward E. coli. Streptococcus faecalis and Salmonella enteritidis, in which the effect of perilla, sorghum and arrowroot was the highest for E. coli. Standard phenolics and food samples did not show any mutagenicity toward Salmonella typhimurium TA98 and TA100. Tannic acid inhibited the mutation of the two strains by benzo[a]pyrene whereas total phenolics fractions of Chinese quince and walnut exhibited antimutagenicity to a lesser extent.

• Journal of Sericultural and Entomological Science
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• no.12
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• pp.37-45
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• 1970

The processing management forms of our country's filature factories in 1969 are summarized as follows. (1) About 80％ of total cocoon collection is made within 5 days involving peak day, and 10％ of cocoon collection is finished until 3 days before and after the peak day, (2) About 92％ of alive cocoons transported on unpaved road, and about 40％ of the cocoons purchased by all factories are loaded on trucks from common selling station which is far beyond 40km, therefore a new packing system of alive cocoons to drop the damage of cocoon qualities, should be taken. (3) 22％ of all factories in our. country have only low-temperature cocoon drying machine. Therefore the installment of hot-air cocoon drying machine is required urgently. (4) In view of cocoon qualities in our country, the grouping method of cocoon for reeling. taken by about 50％ of the factories at percent, which classify cocoons for reeling as high group (1,2,3,4 grades) and low group(5,6 grades), will have to be replaced by the method tat classify them high group (1,2 grades) middle group (3,4 grades), low group (5,6 grades). (5) The .ratio of cocoon assorting stood about 10％ in multi-ends reeling, about 15％ in automatic reeling, conclusively, the ratio of cocoon assorting for automatic reeling was higher tan that for multi-ends reeling. One person's ability for a day in cocoon assorting reaches to about 80-100kg. (6) Cocoon cooking condition requires the increase of the cooking time, the pressure and temperature used to be prolonged as much as the qualities of cocoons are material cocoon ior automatic and double cocoon machines are treated uncompletely. (7) Automatic silk reeling is being performed at 1-2$^{\circ}C$ lower in reeling water temperature and operated at about twice velocity. (8) The temperature and humidity of rereeling room stood at 25$^{\circ}C$, 67.2％ R.H and 32.3$^{\circ}C$, 51.9％ R.H of rereeling machine are showed, Average rereeling velocity is 233m/min and large reefs charged for one person are 7.5 reels and form of skein used in all factories is double skein. (9) About 73％ of water sources for filature used under-earth water. About 48％ of all filature factories in our country have not yet water purifying equipments. Installation of the equipment for these factories seems to be urgent, (10) Denier .balance, sizing reel, seriplane, are being used in most factories as self-inspection apparatus. (11) More than 90％ of the factories use the vacum tank in rereeling process and about 20％ of them use it in cocoon cooing process (12) Only 21％ of the factories use chemicals in filature process. About all them use "Seracol 100" in cocoon cooking process and "Seracol 500" in rereeling process, (13) Above survey results explain each all factories show large difference in the processing management. Therefore, it is believed that intercommunication through seminar or technical exchange will contribute to the production evaluation of cocoon in our filature industry.

• Korean Journal of Agricultural and Forest Meteorology
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• v.3 no.4
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• pp.185-198
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• 2001

This study was conducted to reveal the effects of local climatic conditions on reproductive growth in a mature stand of Korean white pine based on climatic estimates. For this, the reproductive growth such as production and characteristics of cone and seed were first measured and summarized for seven years from 1974 to 1980. The local climatic conditions in the study site were also estimated by both a topoclimatological method and a spatial statistical technique. The local climatic conditions were then correlated with and regressed on the growth factors to reveal the relationships between the climatic estimates and the reproductive growth. Average number of conelet formation per tree showed highly negative correlation with some climatic variables related to minimum temperature in the year of flower bud differentiation. Especially, the most significant negative correlation were found between average of the minimum temperature for June and July of flower bud differentiation year and the number of conelet formation. There was no significant correlation between the number of cone production and climatic variables. However, total precipitation from December of the flowering year to February of the cone production year showed the most high correlation (r=0.6036) with the number of cone production. It was found that significant climatic variables affecting the amount of cone drop and cone drop percentage were the sum of cloudy days from June of the flowering year to August of the cone production year. Positive correlation was significantly recognized between the average weight of empty seed per cone and total precipitation from December of the flowering year to February of the cone production year. For the percentage of empty seed, five climatic variables among 19 variables were significantly correlated at 10% level. The average weight of a cone showed negative correlation with total precipitation from June of the flowering year to August of the cone production year. It was also found that average weight of a seed had highly negative correlation with total precipitation from December of the flowering year to February of the cone production year. The average weight of cone coat was negatively correlated with two climatic variables derived from clear days, which are sum of clear days from November of the flowering year to March of the cone production year and sum of clear days from December of the flowering year to February of the cone production year. On the other hand, it showed positive correlation with mean temperature of May in the flowering year. The exactly same results were obtained in correlation analysis for the percentage of cone coat.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.1
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• pp.8-13
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• 2010

Seedling establishment, overwintering ability and dry matter production of Chinese milk vetch (Astragalus sinicus L. CMV) in natural reseeding practice were compared with the annual seedling in 2006~2007 and 2007~2008. In natural reseeding, CMV seeds were distributed up to 15 cm soil depth in autumn after rice harvest and the seeds generally emerged from soil at less than 5 cm depth while they all emerged from soil surface in the annual seeding. It took 7-8 d longer in seedling establishment of the natural reseeding practice than the annual seeding. Generally, the natural reseeding practice showed higher seedling stand than the annual seeding because of high seedling survival rate. The high seedling survival rate in natural reseeded plant was attributed to the longer root length than that of the annual-seeded plant. In annual seeding, most of the seeds emerged from the soil surface and the root can not easily penetrate the soil while, in natural reseeding technology, the seeds incorporated into the soil during land preparation emerged from the soil at 0 to 5 cm depths, thereby having longer root length. The long root length contributed to greater ability to survive even under low temperature and low soil moisture conditions during winter. The dry matter production in the natural reseeding practice was also higher than the annual seeding when the temperature is low and soil moisture is not sufficient. This result indicates that natural reseeding technology is more stable and beneficial in seedling establishment and dry matter production as compared with the annual seeding especially under unfavorable environmental condition for CMV growth. This practice could be encouraged in CMV-rice cropping system in the southern parts of Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.2
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• pp.149-154
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• 1992

Buckwheat has been a popular favorite food crop in Korea for a long time. The objective of the study was to investigate the effects of climatic conditions and cultural methods on grain yields of summer buckwheat variety Sinnong 1 planted during the spring season in Suwon, Korea from 1989 to 1991. Frost minimum temperature of late April was -0.3$^{\circ}C$ in 1990 being very low as compared with 3.7$^{\circ}C$ of the normal year, and affected early growth of the seedlings emerging from the soil surface. In late May of 1990, the frost minimum temperature was 7.3$^{\circ}C$ being low as compared with 8.8$^{\circ}C$ of the normal year, and also induced cold injury to fertilization and grain filling. Total precipitation 374.5mm of mid and late June, 1990 provided serious damage to the grain filling and maturing buckwheat seeds and along with causing seed sprouting before harvest. However, the climates of 1989 and 1991 were very good for the growth and development of spring-sown buckwheats. When summer buckwheat cultivar Sinnong 1 was planted on April 20, 1989, its highest grain yields 268-292kg /10a were harvested from the plots of seeding rate 8kg /10a, drill seeding and polyethylene film mulching, and the mean grain yield of the plots was 238kg /10a in 1989, but 64.3kg in Suwon, and 40.2kg /10a in Muan in 1990. In 1991 maximum grain yield 277kg /10a was produced from the April 15 planted and vinyl-mulched plot, and 255kg /10a from the April 25 planted and non-mulched plot. Herbicide Alachlor-sprayed plots produced lower grain yields than no weed control and manual weeding plots. Mechanized drill-seeding saved 83～84% in planting hours as compared with manual broadcasting 21.6 hours /ha, and produced 9% more in grain yields from the two-season croppings of mechanized drill-seeding culture being 364kg /10a in total yields per year.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.1
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• pp.110-117
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• 2008

Soybeans (Glycine max) with a black seed coat have been widely utilized as food source and as a medicinal herbs in Korea. The pigmentation in the seed coat of black soybean is due to accumulate anthocyanins in the epidermis palisade layer. The anthocyanin content and composition of the black soybean seed coat are considered as a standard. of quality evaluation of black soybean. The main objective of this study was to investigate the optimal condition for an extraction method of anthocyanins and compare anthocyanin quantity and composition within black soybean varieties and germplasms. In the test of extraction solvent, absorbance at 530 nm and Hunter's a value were increased as increasing the concentration of MeOH, but Hunter's Land b values were the exact opposite of absorbance and Hunter's a values. There was no significant difference for anthocyanin contents from 1% HCl - $H_2O$ to 1% HCl - 80% MeOH. In the aspects of anthocyanin contents and HPLC peak resolution, 1% HCl - 20% MeOH extraction solution was the most suitable solvent. Among the 5 kinds of extraction method using 1% HCl - 20% MeOH solution, the anthocyanin contents of room temperature extraction at 72 h was the highest among the methods. High extraction temperature, sonication and reflux method influenced on the decrease of anthocyanin contents because of breakdown of anthocyanins. There was no significant difference for extraction time between 12 h and 24 h. However, the optimal extraction condition were at room temperature for 12 h. The anthocyanin contents in seed coats of black soybean were determined on the basis of HPLC peak area at 530 nm. Ten black soybean varieties and germplasms were tested with optimal conditions founded in this study. On the basis of antocyanin component, these can be classified into three groups; C3G, C3G + D3G and C3G + D3G + Pt3G. The total anthocyanin content in seed coats ranged from 1.58 to 10.62 mg/g of seed. The total anthocyanin content of the variety "Geomjeongol" was about 7 times higher than that of variety "Heugchong". Information for extraction method and diversity in antocyanin of soybean seed coats can be used for future research for germplasm evaluation and development of high quality black soybean varieties.