• Journal of the Korean Society of Tobacco Science
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• v.5 no.1
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• pp.35-42
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• 1983

This study was conducted to know changes in chemical components and some enzyme activity on tobacco leaves of NC2326 and Hyangchio (Nicotiana tabacum L. ) by different curing methods. The activity of $\alpha$, $\beta$-amylase and invertase of flue-cured tobacco variety NC2326 were higher than that of sun-cured variety Hyangchio. And the peak of all of enzyme activity in both varieties showed at about 60 hours (at color fixing stage) and 6 days (yellowing stage) after start of flue-curing and sun-curing, respectively. The peak time of reducing sugar content were same with the maximum enzyme activity during curing process in both varieties. During both curing process, the content of starch was greatly reduced and there was a corresponding increase in reducing sugars. Increase in total alkaloids content continued during flue-curing process in both varieties, but during sun-curing process total alkaloids content of NC 2326 were Increased whereas those of Hyangchio were decreased markedly.

• Applied Biological Chemistry
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• v.19 no.4
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• pp.219-226
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• 1976

To meet the need of protein feed and fine more efficient ways of returning waste to resources, we have carried out the study of the production of yeast for foods and feeds from the corn starch cake. The present study includes the method for acid-hydrolysis, the selection of yeast capable of utilizing hydrolyzate of the corn starch cake, and culture condition of Candida tropicalis under the liquid culture and the semisolid culture. Obtained results were as follows. 1. Hydrochloric acid was more excellent on the hydrolysis of the corn starch cake than sulfuric acid, and the yield of sugar was maximum, 57.2%, when the corn starch cake was hydrolyzed with 1.0% of hydrochloric acid at 2.0kg/cm for 30 minutes. 2. As the acid solution content was increased, more sugar was liberatedfrom the mixture, until the acid solution-substrate ratio reached 10:1. Beyond this point, no further increase was observed. To prepare the cultural medium of semisolid fermentation, a acid solution to substrate ratio of 3:1 appeared to be optimum. 3. Out of 6 yeast strains, Candida tropicalis had excellent growth on the hydrolyzate of the corn starch cake, and optimum temperature and initial pH were $30^{\circ}C$ and 6.0 respectively. 4. Optimum liquid medium of Candida tropicalis is ures 0.3%, potassium phosphate monobasic 0.15g and magnesium sulfate 0.04g in 100ml of the hydrolyzate of the corn starch cake, while optimum semisolid medium is ammonium chloride 0.4g, potassium phosphate monobasic 0.1%, magnesium sulfate 0.04%. 5. Candida tropicalis could assimilate the sugar in the hydrolyzate up to more than 88.75%, and a yield of dry yeast reached 19.13% to the corn starch cake under the liquid culture. 6. Compared to the that of the untreated corn starch cake, the cellulose content of the semisolid fermented cake decreased by 3.76% to 14.7%, whereas dry yeast contents increased by 13.89%.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.9
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• pp.1182-1189
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• 2008

Changes of free sugar on Gugija-sugar leaching were investigated by adding sugar on Gugija (Lycii fructus) raw fruit. Gugija were prepared by parboiling ($40{\sim}50$ sec at hot water of $85^{\circ}C$) and unparboiling. Gugija-sugar leaching were leached after preserving (5 and 10 months at $5^{\circ}C$) Gugija-sugar mixture (ratio of raw Gugija and sugar, 1:0.2, 1:0.4, 1:0.6, 1:0.8, and 1:1/w:w). Soluble starch content of Gugija-sugar leaching increased with increasing ratio of sugar without reference to parboiling treatment, having the highest content, 2.5% at UPRGSL-4 (unparboiling Gugija:sugar, 1:0.8 leaching). Maltose content increased with increasing ratio of sugar in PRGSL, being the highest at 12.66% in PRGSL-5 (parboiling Gugija:sugar, 1:1 leaching) at 10 months leaching periods. Most of the sucrose went out of existence with increasing leaching periods; content was 4.22% on PRGSL-5 and 1.36% on UPRGSL-5. Content of glucose and fructose increased with increasing ratio of sugar; glucose content was 7.86% on PRGSL-4 and 26.22% on UPRGSL-5, at 10 months leaching periods. Fructose content was 18.46% on PRGSL-5 and 22.51% on UPRGSL-4 at 10 months leaching periods. Contents of sorbitol and glycerol increased with increasing ratios of sugar.

• Journal of the Korean Society of Tobacco Science
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• v.3 no.1
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• pp.20-24
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• 1981

This experiment was carried out to determine the relationships between maturity and content of the chemical components in flue-cured tobacco. The results were as follows : 1) Among the chemical components, the contents of total nitrogen, ammonia nitrogen, total alkaloids, nicotine, total volatile base, petroleum-ether extract, crude fiber, crude ash, water soluble ash, and chlorine decreased significantly, and those of total sugar, reducing sugar, and starch increased as leaf maturity progressed until the stage of ripeness, but, afterwards, a reverse tendency appeared. 2) There was a significant relationship between maturity and the contents of chemical components, such as total nitrogen, protein nitrogen, ammonia nitrogen, total volatile base, and the correlation coefficients of them were -0.743, -0.789, -0.797, and -0.642, respectively.

• Korean journal of food and cookery science
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• v.7 no.4
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• pp.9-13
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• 1991

Nochi is a kind of Korean traditional food made from glutinous rice or millet. This study attempted to examine the effects o( the various factors and to clarify the factors which affect the overall eating quality of Noch. The results were summarized as follows. 1. Starch content of waxy rice was 72.4% and IBC was 0.017%. 2. $\alpha$-amylase and $\beta$-amylase activity of malt were 40.13 and 8.94 units respectively. 3. Waxy rice soaked for 3 hours was ground to flour then sifted 20 mesh sieve. The mixture of waxy rice and malt was steamed for 20 minutes. 4. In sensory evaluation on varying the amount of malt and incubation time, the most favorite tendancy of the overall eating quality was at the level of 8hours incubation made by 5% addition of malt. 5. Total sugar contents, reducing sugar contents and the intensities of iodine stain at the incubation temperature of $60^{\circ}C$ were significantly different from those at $50^{\circ}C$.

• The Korean Journal of Community Living Science
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• v.22 no.4
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• pp.573-578
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• 2011

This research was conducted to enhance the value of low quality sweet persimmon by processing paste by combining low quality sweet persimmon and red-bean. In order to make sweet persimmon paste containing red-bean, the following procedures were executed : 1) the sweet persimmon was cleaned by water 2) the fruit stalk was removed 3) it was peeled, sliced, pitted and crushed 4) steamed and peeled red-bean paste was mixed 5) sweetening materials(starch syrup, sugar and dextrin) and salt were mixed 6) boiled and stored in refrigerator. Sweet persimmon was peeled, stem and seed was removed to make the paste. When mixing sweet persimmon paste and red-bean paste in the ratio of 6 : 4, sensory point of taste and overall desirability were higher than mixing in 5 : 5 and 4 : 6 but texture was lower. The sweet persimmon paste containing red-bean was softened and the sugar content was increased from 41.4$^{\circ}$Brix to 53.1$^{\circ}$Brix when 10% dextrin was added. The overall sensory evaluation was higher in sweet persimmon paste containing red-bean than commercial red-bean paste when 10% dextrin was added. The overall desirability also shown a significant difference between them. Even though findings were statistically insignificant, sweet persimmon powder with red-bean paste increased in texture and overall desirability compared with commercial red-beans paste. Sweet persimmon powder paste containing red-bean significantly decreased in flavor, color, taste and overall desirability compared with sweet persimmon paste containing red-bean. As a result of this study, the best combination for the quantity of sub-materials to make sweet persimmon paste was 600g of sweet persimmon, 400g of red-bean, starch syrup 120g, sugar 60g, salt 4g and dextrin 100g.

• The Korean Journal of Food And Nutrition
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• v.31 no.1
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• pp.80-88
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• 2018

This study was conducted to develop easily chewable Korean rice cake (Garaedduk) for the elderly while maintaining its original form and flavor. We developed two types of easy-to-chew Garaedduk products by adding starch-degrading enzyme or trehalose, respectively. Characteristics of Garaedduk products were investigated and comparative analysis was carried out between control and experimental groups. The water content of control and enzyme-added Garaedduk was 43.55% and 44.11%, respectively, which was significantly higher than trehalose-added Garaedduk (40.30%) as free water content was reduced by the formation of hydrogen bonds between trehalose and water molecules. Due to the browning of reducing sugar produced by the decomposition of rice starch, Hunter b-value of enzyme-added Garaedduk was significantly higher compared to others. Hardness, adhesiveness, gumminess, and chewiness of experimental groups were lower than the control group. Consumer test scores showed significant differences with respect to overall liking, chewiness, and swallowing between control and experimental groups. Elderly preferred experimental Garaedduks over control and the experimental groups were evaluated to be softer, easily chewable, and swallowable.

• Korean Journal of Food Science and Technology
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• v.18 no.6
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• pp.431-436
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• 1986

The action of crude amylolytic enzymes extracted from Wonki and Chunmi sweet potatoes, ${\alpha}-amylase$, and ${\beta}-amylase$ on the sweet potato starches from Wonki (dry type) and Chunmi (moist type) were studied. The activity of crude amylolytic enzyme extracted from Wonki was higher than that extracted from Chunmi. The content of reducing sugar released from the reaction between crude amylolytic enzyme and Chunmi starch preheated at $70^{\circ}C$ was higher, but that preheated at $95^{\circ}C$ was lower than that from Wonki starch preheated at the same temperature. The activites of ${\alpha}-amylase$ and ${\beta}-amylase$ on the Wonki starch were higher than those of the Chunmi starch at the same conditions. Iodine affinity of amylolytic enzyme-treated starch was decreased and enzyme treated starch granule shape was found with porous structure having inner layers. X-ray diffraction patterns of amylolytic enzyme-treated starches were the Ca type like the intact starches and relative crystallinity was decreased.

• Applied Biological Chemistry
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• v.37 no.2
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• pp.77-84
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• 1994

Sweetpotatoes were baked (BK), microwaved (MW), microwaved/baked (MWBK), and microwaved/hold/microwaved (MWHO). Sugars, Huntercolors, compression and shear forces, sensory scores, moisture content, starch, and alcohol insoluble solids (AIS) were determined for each treatment. The BK roots contained higher (p<0.05) amount of sugars and less (p<0.05) starch. The MW roots contained higher (p<0.05) amount of starch, AIS, and less (p<0.05) sugar. The BK product resulted in the least (p<0.05) compression and shear forces needed to break it. The MW product demanded the greatest (p<0.05) force. The MWHO showed very similar results to the BK. Sensory scores for the BK and the MWHO sweetpotatoes were very acceptable. In color scores, the MWHO products were very acceptable and similar to the BK in flavor.

• Korean Journal of Agricultural Science
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• v.27 no.2
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• pp.81-85
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• 2000

In order to find a proper storage temperature and times for vegetable waxy corn, several waxy hybrids used in the study. Among waxy hybrids, stem height and ear length of Daehakchal and Eulrukchal hybrides were higher than Chalok#1 and #2 used as a check, but flowering daus were later about 7 days than check. Sugar content of Daehakchal was not almost changed at $-4^{\circ}C$ and below, whereas it was rapidly decreased at $4^{\circ}C$. Most hybrids with high sugar content were fast converted into starch than lower content hybrid. While moisture contents of waxy hybrids used were almost constant regardless of storage temperature in vegetable com packaged with poly ethylene vinyl. From these results, storage temperature of vegetable waxy corn was recommended at least $-4^{\circ}C$ below. Under the $-10^{\circ}C$ and below, storage period of vegetable waxy corn could prolong 60 days and above because sugar and moisture content of vegetable corn measure at $-10^{\circ}C$ and $-20^{\circ}C$ were almost no changed compared with those of fresh corn measured at harvest.