• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.3
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• pp.267-272
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• 1999

In order to determine the optimum harvest time of vegetable corns, the changes in sugars, soluble solids, and flavor of kernels of sweet (cv. ‘Golden Cross Bantam 70’), super sweet (cv. ‘Cocktail E-51’), and waxy corns (cv. ‘Chalok 2’) were observed at different ripening stages. Sucrose was a major sugar in the sweet and super sweet corns and the content increased from 15 to 21 and 27 days after silking (DAS), respectively and then decreased. Glucose and fructose contents of sweet and super sweet corns tended to decrease with kernel maturity. Total sugar content of the sweet corn analyzed by the anthrone method increased rapidly from 15 to 21 DAS, while that of the super sweet and the waxy corns increased slowly up to 24 and 26 DAS, respectively and decreased thereafter. The content of soluble solids in sweet corn was much higher than that of super sweet corn. Starch content of the sweet corn increased slowly from 15 to 33 DAS, while that of the super sweet corn increased a little rapidly from 15 to 21 DAS and then leveled off to 33 DAS. Starch content of the waxy corn increased continuously from 21 to 38 DAS. There was a positive correlation between the sum of individual sugars (sucrose, glucose, and fructose) and soluble solids in both sweet and super sweet corns, while the content of soluble solids was not related to the sum of individual sugars or total sugars. The flavor rate of sweet and super sweet corns maintained high between 21 and 27 DAS and that of waxy corn decreased from 24 to 33 DAS. The optimum harvest time for sweet, super sweet, and waxy corns was thought to be 21 to 24 DAS considering sugar and starch contents, flavor, and marketing.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.4
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• pp.445-456
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• 2014

This study was conducted to investigate the kernel characteristics of sweet corn during ripening with different sowing date. Godangok and Guseulok were sown at April 10, July 10, July 20, and July 30 in 2013. Irrespective of sowing date, fresh and dry weight of 100 kernel, starch content, crude fat content, and hardness of sweet corn kernels were significantly increased according to maturation (p<0.05). But moisture content, total sugar content, crude protein content and crude ash content of sweet corn kernels were significantly decreased according to maturation (p<0.05). The changing rates of 100 kernel weight and starch content on kernels were faster at early sowing date than at late sowing date. The moisture content of sweet corn kernels was 68~69% at optimum for harvesting. The degree of sweetness on Godangok was about 1.8 and 1.4 times higher in sowing at July 20 and July 30 than in sowing at April 10. On the other hand, the degree of sweetness was similar regardless of sowing time on Guseulok. These results will be helpful to farmers for fall-harvest sweet corn cultivation and management.

• Korean Journal of Food Science and Technology
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• v.17 no.5
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• pp.399-402
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• 1985

Polished rice was stored for 24 weeks at $28^{\c수분함량이 16.0% after infestation with rice weevil (Sitophilus oryzae), inoculation with a storage mold, or both treatment. The moisture contents of stored rice with and without rice weevil were 16.6%-17.3% and 13.70%-14.1% respeotively. Fungal numbers were $4.3{\times}10^{6}$/g to $7.2{\times}10^{6}$/g with insects while no fungal growth occurred without them. There were considerable differences between rice weevil infested- and non-infested rice in rice kernel hardness, 1000 kernel weight, maximum viscosity on amylogram, reducing sugar content, fat acidity, and n-hexanal content in head space gas.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.3
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• pp.176-180
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• 2000

The higher sugar and lower starch in super sweet corn may be due to modified endosperm genes sh, bt series, but its seeds have major limiting factors causing low germination and low seedling vigor, This study was conducted to determine what measurable kernel characteristics during the grain tiling period might be more useful as a guide to optimize harvest date for good seed quality in hybrid super sweet corn production. Artificial crossing in super sweet corn hybrid (Chodangok 1) was made on the same day, and ears were harvested from 18 days to 53 days after pollination at weekly intervals. Kernel weight, moisture content, hardness, endosperm rate, seedling height and storage nutrients such as sugars, protein, starch, and germination rate were measured for the kernels at each harvest. Super sweet corn hybrid, Chodangok 1 presented satisfactory germination rate above 70% when harvested on 39 to 46 days after pollination. Its storage nutrients at that time were 23.7-24.2% in starch content 5.5-5.9% in total sugars, 38.9-46.6% in kernel moisture, and 62.7-64.2% in endosperm rate. Germination rate was extremely high when harvested on 39 days after pollination. The black layer of Chodangok 1 could not be used as an indicator for seed harvest. These results suggested that optimum harvest date seems to be 39 days, and kernel moisture and starch content could be used as indications of kernel maturity in deciding when to harvest fer good seed quality in super sweet corn.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.1
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• pp.73-78
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• 1994

This experiment was carried out to investigate the major characteristics associated with the flavor rate and their changes according to days after silking of super sweet corn(Cocktail 86) for vegetable and waxy corn(Chalok 1). Ear elongation finished around 22∼24 days after silking. In kernel development, elongation was much more prominant in super sweet corn than that in waxy corn but thickness was vice versa. Pericarp thickness and kernel hardness of super sweet corn were slightly increased but those of waxy corn were increased rapidly as the ears matured. Moisture and sucrose content of super sweet corn remained high but the waxy corn was not. The reducing sugars(glucose, fructose) were relatively high at the early maturity stage but they were decreased as the ears matured and negatively correlated with sucrose and flavor rate. Soluble solids (Brix %) were positively correlated with sucrose and total sugar(sucrose+ glucose+fructose) content in waxy corn but not in super sweet corn and was considered as inappropriate criate criterion to envaluate the sugar content and flavor rate. Pericarp thickness and sucrose content were positively correlated with the flavor rate in both hybrids but total sugar content, and kernel hardness were positively correlated with flavor rate in super sweet corn and waxy corn respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.spc1
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• pp.161-166
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• 2005

Objectives of this study were to select inbred lines which have a good eating quality and desirable segregates during inbreeding of waxy corn. The 64 inbred lines showed a large variance in their kernel shape and weight. 100-kernel weight, pericarp thickness, kernel length, kernel width, and kernel thickness ranged $11.7\~37.3g,\;11\~77{\mu}m,\;5.8\~9.6mm,\;6.5\~10.0mm$, and $4.1\~6.8mm$, respectively. The physicochemical analysis of 64 waxy corn inbred lines showed crude protein, crude fat, free sugar, and amylopectin content ranging $8.7\~15.8\%,\;2.3\~5.8\%,\;1.1\~11.0\%,\;and\;78.5\~93.8\%$, respectively. The texture property analysis of 64 inbred lines by texture analyzer showed a big difference. Gumminess, hardness, and chewiness of 64 inbred lines ranged $91\~383,\;181\~394,\;and\;73\~370$, respectively. The principal component analysis for 14 characteristics related to kernel quality showed that $73.1\%$ of the total variation could be attributed to the first five principal components. Biological meaning of the principal component was explained clearly by the correlation coefficient between principal components and characters. The first principal component appeared to correspond to small kernel and bad eating quality, The second principal component appeared to correspond to large kernel and good eating quality. The 64 inbred lines were classified into 8 groups by the cluster analysis using the first and second principal component. Among the groups, group VII and VIII included inbred lines with good eating quality that had thin pericarp thickness, low protein content, large kernel, and soft tenderness.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.1
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• pp.17-22
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• 2015

A total of CNU 28 hybrids were developed at the CNU Corn Breeding Lab. were evaluated to identify new cultivars in botanical characteristics, fresh yield per 10a and taste qualities. Most of these hybrids were stable in environmental stresses such as lodging, disease and insects. Stem height ranged from 115.0 to 239.3 cm, and ear height ranged from 30.7 to 107.0 cm. The ear height to stem height ratio was showed low than 50% of standard as a stable plant type to lodging. The range of ear length was 14.2 cm to 23.0 cm. Especially, CNU 13H-73 was very longest ear as a 23 cm. The fresh yield per 10a was high in purple of CNU13H-79 hybrid than control hybrid Miheuckchal, and CNU13H-73 in white hybrid was similar Yeonnong check hybrid. The 100-kernel weights in CNU13H-3 and CNU13H-9 hybrids were higher than that of the control hybrid. CNU13H-98 among hybrids had a 100-kernel weight of 20.32 g, which was heavier than that of the control hybrid Daehackchal Gold 1. The average pericarp thickness was $41.4{\mu}m$, CNU13H-46 among hybrids had a very thin pericarp as a $35.5{\mu}m$. The mean sugar content of the used hybrids was 14.95 brix%; CNU13H-73 and CNU13H-55 had higher than Mibak2 as a control hybrid.

• Korean Journal of Breeding Science
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• v.42 no.3
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• pp.212-217
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• 2010

A new waxy corn hybrid 'Daedukchal 1' was developed from single cross between CNU 504 and CNU 2396 at Chungnam National University in 2007. Inbred CNU 504 used as a seed parent and inbred CNU 2396 as a pollen parent were collected throughout domestic regions. Tasseling date of this hybrid was seven days later than that of check hybrid, 'Chalok 1'. 'Daedukchal 1' was 19.7 cm in ear length and 4.5 cm in ear diameter. On yield trial, ear length of this hybrid was increased 29.7% compared with a check hybrid, 'Chalok 1'. 'Daedukchal 1' had white kernels and good eating quality due to high sugar content and thinner pericarp. The ratio of kernel set length/ear length was similar to 'Chalok 1'. It is moderately resistant to southern leaf blight and northern leaf blight but susceptible to corn borer. The yields of 'Daedukchal 1' in fresh ear weight and in number of fresh ear were 16% and 8%, respectively, higher than those of a check hybrid in regional yield trials for two years. Seed production for this hybrid was better because of the consistency of tasseling dates.

• Journal of Applied Biological Chemistry
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• v.62 no.1
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• pp.25-30
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• 2019

This study investigated the quality changes in whole super sweet corn during thermal processing to extend its shelf-life. To minimize the reduction of unique texture of whole sweet corn after the sterilization, the alcohol sanitation applied and the cold point of a whole corn ear was determined using a computer simulation. The cold point was located between the corn kernel and the cob. The microorganisms on the surface of sweet corn were reduced by more than 1 log CFU/g after alcohol sanitation, then the whole corn was treated to satisfy the degree of sterilization ($F_{121.1}=4$). The quality of sterilized sweet corn was compared with the control that was treated with steaming. The quality changes of sterilized sweet corn during storage were monitored for 9 months at $25^{\circ}C$. The hardness was maintained within 30% of its initial value. The minimum of hardness was $464.50{\pm}103.35g$ and maximum of hardness was $514.50{\pm}81.83g$. The differences in the sugar content among the samples were found, but the sugar content of corn kernel remained within 30% of the control, ranging from $28.83{\pm}1.05$ to $34.36{\pm}0.42%$. The yellowness was higher than that of control by 5%. The maximum value of yellowness was $34.36{\pm}0.42$. The general bacteria and molds and yeasts in corn kernel stored at $25^{\circ}C$ were not detected after 9 months of storage at $25^{\circ}C$. Therefore, in this study, we have demonstrated that the thermal sterilized method extends the shelf-life of whole sweet corn with minimizing its quality changes over 6 months in room temperature.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.1
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• pp.136-142
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• 2012

Sogokju, a Korean glutinous rice wine and one of the oldest Korean traditional wines, is famous for its unique taste acquired from a 100-day incomplete fermentation process. This study investigated the effects of the degree of rice milling on the physicochemical and sensory characteristics of Sogokju. It evaluated the physicochemical characteristics, pasting and color properties, and structural properties of starch using four different degrees of milled rice (Oryza sativa L.) cultivar Dongjinchalbyeo. Samples of brown rice with milling yields of 92%, 84%, 76%, and 68% were produced using both abrasive and friction whiteners. This study showed that the protein, lipid, and ash content of milled rice decreased as the degree of milling increased. The lower hardness of the kernel below milling yield 92% suggested that milling may be related to the lower protein content of the kernel. The pasting curve showed a significant increase in viscosity properties as the degree of milling increased. This is due to the decrease in protein and lipid content, the increase in starch content, and the difference in amylopectin chain-length distribution. Further milling of white rice, based on 92% milling yield, had an effect on the amylopectin chain-length distribution due to the degree of polymerization (DPn) of 37~60. The long chain of amylopectin also contributed to the viscosity. The increase in the degree of milling decreased the glucose and total sugar content of Sogokju. However, it increased the total acidity of Sogokju. Moreover, the lightness of Sogokju decreased while its yellowness increased. These results indicate that the degree of milling can alter the taste and color of Sogokju. The sensory evaluation showed that the increase in the degree of milling decreased consumer preference for Sogokju. The sensory score for Sogokju was positively correlated with its brix degree, glucose content, pH, and protein content of raw rice.