• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 1998.10b
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• pp.10-10
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• 1998

The growth process of solid grains in a liquid matrix is usually explained in tem1S of Ostwald ripening. The variation of growth (dissolution) rate as a function of grain size during Ostwald ripening predicted that the dissolution rate becomes very large as grain size decreases but the growth rate of a large grain is rather limited. Therefore. a rather uniform size distribution of grain size is maintained once after the quasi-equilibrium state is reached. Quite frequently, however, the exaggerated grain growth (EGG) is observed to occur: only a limited number of grains grow exceptionally. From the observation that the EGG occurs only for the faceted grains with apparently straight solid-liquid interfaces, the EGG is suggested to be the consequence of growth process controlled by 2-dimensional nucleation. In this study, the result by computer calculation on the grain growth process controlled by various mechanisms will be given.

• Journal of Ginseng Research
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• v.16 no.1
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• pp.37-43
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• 1992

Structural changes of the endosperm of Panax ginseng C.A. Meyer from fertilization to germination were investigated by light microscope. The endosperm of the ginseng seed is cellular type. Since endosperm cells adjacent embryo continuously breakdown and disappear with the elongation of embryo, the real of endosperm is gradually decreased. As the anatropous ovules of immature seed with green seed coat developes more and more, ovary cells adjacent ovary cavity become abundant by the periclinal division, their size is decreased, hypotrophy of cell wall discern, and they are gradually differentiated in seed coat. Though embryo responds strongly to basic dye at the stage of completion of endosperm formation, tissue of endosperm responds to acidic dye positively Cell wall of embryo and endosperm are composed of primary cell wall not lignified. Endosperm cells adjacent embryo begin to breakdown in the endosperm tissue of indehiscent seed before the beginning of the after-ripening. Dehiscent seed of which seed coat is opened through after-ripening represent the form as a seedling in the result of embryo developments with the formation of organs; radicle, cotyledon, plumule. Umbilifom layer represents strong positive response to the toluidine blue and the basic function. Umbiliform layer that endosperm cells breakdown and disappear is observed clearly at the periphery of the embryo cotylemon, while slightly at the periphery of the radicle.

• Microbiology and Biotechnology Letters
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• v.9 no.3
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• pp.153-157
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• 1981

After Penicillium candidum and Actinomucor elegans were inooculated to soybean curd and incubated for 4-6 days at 10-13$^{\circ}C$, respectively, and the fresh soybean cheeses were soaked in ethanol-brine solution which was composed with 10% ethanol and 5% sodium chloride, for 16 weeks at above temperature. Total nitrogen content of soybean cheese was reduced by eloping the ripening time, but in soaking solution the content was increased. In amino nitrogen and reducing sugar of the cheese and the solution, the contents were continuously increased to the certain period, and after that time the rate was stupid. Nitrogen in the cheese inoculated with Act. elegans was highly hydrolysed and amino nitrogen and reducing sugar were much more produced than that inoculated with Pen. candidum.

• Korean Journal of Food Science and Technology
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• v.38 no.4
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• pp.469-474
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• 2006

This study was carried out to investigate the changes of physicochemical characteristics of Schizandra chinensis during postharvest ripening for 8 days at various temperatures. The juice yield of S. chinensis, which was 55.7% before postharvest ripening, was unchanged $(55.3{\pm}0.6-56.3{\pm}0.6%)$ at $4^{\circ}C$ storage, but was decreased at the level of 6 and 7% at $25^{\circ}C$ and room temperature (RT), respectively. During storage at $25^{\circ}C$ and RT, the titratable acidities of S. chinensis were the highest at $7.49{\pm}0.03$ and $7.20{\pm}0.03%$ after 6 days of postharvest ripening, respectively. During storage at $25^{\circ}C$ and RT, the soluble solid content of S. chinensis was increased from $8.2{\pm}0.1%$ at initial stage to a peak of $12.2{\pm}0.15%$ at 6-day storage, after which it decreased. L values (lightness) of S. chinensis were increased in all treatments during storage, and a values (redness) of $25^{\circ}C$ and RT treatments were increased from 5.04 initially to 6.77 and 7.65 at 8-day storage, respectively. The major free sugars of S. chinensis were fructose (0.55%), glucose (0.56%), and sucrose (0.50%). During storage at $25^{\circ}C$ and RT, the fructose and glucose contents were continually increased with increasing storage period, while the sucrose contents decreased after 6-day storage. Major non-volatile organic acids of S. chinensis were succinic (1.21%), citric (0.17%), and malic (0.07%) acids. Changes in the organic acids contents of S. chinensis at various temperatures showed a similar tendency to that of the free sugars. We estimated that the best conditions for the postharvest ripening of S. chinensis were 8 days at $4^{\circ}C$ storage, and 6 days at $25^{\circ}C$ and RT.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.11
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• pp.1731-1736
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• 2014

The quality characteristics, enzyme activity, and antioxidative activity of fermented wild grass juices were investigated during fermentation and ripening for 6 months. Fermented wild grass juice was prepared from wild grasses (Oenothera biennis, Portulaca oleracea, and Rhus verniciflua) and sugar. Wild grasses and sugar mixed at the same ratio (1:1, w/w) and ripened at $20^{\circ}C$ for 3 months after fermentation for 3 months at $20^{\circ}C$. The $^{\circ}Bx$ of all fermented wild grass juices (FWGJ) decreased during fermentation. The pH of all FWGJ decreased gradually during fermentation and did not show any significant difference during ripening. Viscosity of FWGJ increased during fermentation but decreased during ripening periods in all tested samples. Total viable cell of FWGJ decreased after fermentation for 1 month, whereas lactic acid bacteria were not detected during fermentation. Enzyme activity was lower than 1 unit during fermentation and ripening period in all tested FWGJ samples. Enzyme activity of commercial FWGJ (Acanthopanax sessiliflorum, Oenanthe javanica, Plantago asiatica L., Platycodon grandiflorum, Orostachys japonicus A.) showed lower activity of 1 unit following invertase, cellulase, and amylase activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.2
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• pp.131-135
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• 1984

For the convenience of transportation and improvement of the utility of raw chinese cabbage during harvest season, the condition of pretreatment for the raw chinese cabbage with pickle has been examined by preserving for one to ten days. The changes in the content of riboflavin and ascorbic acid in kimchi (pickled-seasoned chinese cabbage), which was manufactured by using the pickled cabbage as a main raw material, along with ginger, garlic, red pepper powder, rad-dish and fermented shrimp as seasonings, during ripening were investigated with specially referred to palatability. The yield of the pickled cabbage compared to the raw cabbage after treating with pickle was 62 to 65% in volume and 15 to 42% in weight. After 10 days of pickling of the chinese cabbage, one-third of total ascorbic acid was diminished but no change in riboflavin content was observed. During ripening of kimchi, riboflavin content in kimchi processed with the pickled cabbage has not been changed compared to the content in convention- ally made kimchi, however, slight decrease in ascorbic acid content in the kimchi processed with the pickled cabbage was as certained. The result of organoleptic test showed that the kimchi processed with the pickled cabbage became inferior to the conventionally made kimchi with the days of ripening.

• Applied Biological Chemistry
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• v.41 no.7
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• pp.510-515
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• 1998

Effect of freezing of soybean and addition of mugwort on the flavor development and the changes of chemical compositions in Chungkookjang was investigated. The changes in the amount of amino-type N, the activities of ${\alpha}-amylase$ and protease, and the content of volatile compounds were determined during aging of Chungkookjang. During ripening, a little higher protease activity was detected in Chungkookjang made of frozen soybean than in that made of non-frozen soybean. However, the profile of ${\alpha}-amylase$ activity of Chungkookjang made of frozen soybean was very similar to that of Chungkookjang made of non-frozen soybean. The amount of amino-type N increased gradually with the ripening period and decreased after 21 days of ripening. The amount of amino-type N was slightly higher in Chungkookjang made of frozen soybean than in that made of non-frozen soybean. Addition of mugwort had little effect on the enzyme activities and the amino-type N content. The mugwort added in Chungkookjang reduced the production of cis-3-hexenol which is responsible for the unpleasant odor, and freezing of soybean enhanced the production of 2, 6-dimethyl pyrazine which is contribute to the taste. According to sensory evaluation, flavor was the highest after the 14 days of ripening and addition of mugwort increased significantly the flavor in both Chungkookjang prepared with frozen soybean and Chungkookjang with non-frozen soybean. However, the effect of freezing of soybean on the flavor was not significant.

• Food Science and Preservation
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• v.15 no.2
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• pp.311-316
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• 2008

We studied changes in a high-proof maesil liqueur during a 5 month leaching and ripening period at $10^{\circ}C,\;20^{\circ}C$, and $30^{\circ}C$. Titratable acidity increased after 2 months at all temperatures, but pH only changed after 2 months at $30^{\circ}C$. The absorbance at 420 nm increased significantly during a high temperature leaching and ripening period. The alcohol concentration was similar for maesil liqueurs held at $10^{\circ}C$ and $20^{\circ}C$ for 2 months. The levels of reducing sugars and polyphenols were also higher for liqueurs stored at higher temperatures. The major free sugars present after one month (in order of decreasing concentration) were fructose, glucose, sucrose, and maltose. The major organic acids were citric, lactic, malic, succinic and acetic acid The total organic acid content of maesil liqueur decreased after 1 month at $10^{\circ}C$ but increased until 2 months at $20^{\circ}C$ and $30^{\circ}C$.

• Journal of Nutrition and Health
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• v.13 no.3
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• pp.150-154
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• 1980

For the purpose of clarifying the changes of free amino acid content in seeds of Korean mung bean during the ripening process, samples ranging in five stages-10, 15, 20, 25 and 30 days after blooming were collected. The results obtained were as follows: 1) Amino acids detected in the first stage were lysine, histidine, arginine, cystine, aspartic acid, threonine (including serine), glutamic acid, valine, methionine sulfoxide and methionine sulfone. 2) In the second stage (15 days after blooming) more amino acids such as glycine, isoleucine, tyrosine, phenylalaninc, and methionine were detected in addition to those in the first stage. More methionine was appeared, while the level of methionine sulfoxide and methionine sulfone was decreased. 3) In the 3rd stage leucine was first detected. The level of leucine was increased slowly as the seed was being ripened. After 4th stage methionine sulfoxide and methionine sulfone were not detected, while the level of methioniene was steadily increased. 4) After 20 days the levels of lecuine, valine. isoleucine, and methionine were increased, while the others were either decreased or remained at the same level.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.2
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• pp.87-95
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• 2017

The increase in the frequency of occurrence of abnormal weather could include severe rainfall, which could cause rice submergence during the ripening stage. This experiment was conducted to clarify the effects of submergence during the ripening period on yield and quality of rice. The flooding treatment was conducted at 7 and 14 days after heading. Flooding conditions were created with two conditions, flag leaf exposed and overhead flooding, and each condition was divided into two conditions according to water quality-clear and muddy. Although the yield decrease was more severe at 7 days after heading because of the decrease in the ripening ratio, the head rice ratio was more affected at 14 days after heading because of the increase in the chalky kernel ratio. The maximum quantum yield (Fv/Fm), which indicates the photosynthetic efficiency, did not differ before and after the flooding treatment until flooding continued for 4 days. In addition, stem elongation occurred because of flooding as an avoidance mechanism in japonica rice. This phenomenon was expected to decrease the supply of assimilation products to the spikelet (sink). Overall, it was suggested that additional experiments should be conducted examining the change in the starch synthesis mechanism and transfer of assimilate products resulting from submergence, for development of cultivation techniques corresponding to submergence and breeding of varieties with submergence tolerance characteristics.