• Korean Journal of Food Science and Technology
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• v.15 no.4
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• pp.392-398
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• 1983

A pilot single-screw food extruder was constructed, and its mechanical properties and product characteristics were investigated by using corn grits. The screw rotational speed was varied and the changes in temperature profile of the barrel for the start-up period of operation were measured. The rate of heat generation for the start-up period was affected by the screw speed and feed rate. The screw speed resulted in a great influence on the estimated dough viscosity. The changes in the dough viscosity could indicate the on-set of termoplastic reaction in the barrel. The expansion ratio during the start-up period mainly depended on the barrel temperature and the degree of thermoplastic reaction in the barrel. The barrel temperatures for the gelatinization and burning of corn grits depended on the screw speed as well as the feed rate.

• The Korean Journal of Food And Nutrition
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• v.24 no.2
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• pp.239-245
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• 2011

The purpose of this study was to investigate the quality of sugar-snap cookies containing various types and mixture ratios of sugar. The characteristics of sugar-snap cookies prepared with fructose, high-fructose corn syrup and invert sugar were examined through physical properties measurement and sensory evaluation. Results of the investigation suggest significant differences in the cookies made with various sugars. High-fructose corn syrup was better than others for making sugar-snap cookies. The quality of cookies baked with high-fructose corn syrup was improved compared to cookies baked with invert sugar or fructose. Varying the formula, with high-fructose corn syrup had little or no effect on the quality of the final product. Using different quantities of invert sugar and high-fructose corn syrup significantly affected the physical properties of the cookies. Sugar-snap cookies containing invert sugar had an extremely positive effect.

• The Korean Journal of Mycology
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• v.39 no.3
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• pp.171-174
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• 2011

This study was carried out to elucidate suitable supplementary nutrition for Neolentinus lepideus cultivation. The main substrate for cultivation was douglas fir sawdust, and supplementary materials for experiment were corn meal, corn hull, corncob, beet pulp, and potato starch. The higher amount of total nitrogen source was showed in corn meal (0.45%) than any other nutritive materials. Incubation ratio and cultivation period showed the best 97% and the shortest 43 days on medium with corn meal substrate. The fruit body yield and biological efficiency on medium with 10% corn meal were highest 122 g/1 kg and 35%, respectively. Factor analyses concerning fruiting yield showed total nitrogen source (r = 0.95) and crude fat (r = 0.65). These results are recommended that N. lepideus cultivation is corn meal material as the source of the supplementary nutrition and total nitrogen source as the factor of fruiting body yield on the Douglas fir sawdust medium.

• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.475-478
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• 1994

The hydrolyzability of chemically modified starches and ramen staches was determined by hog pancreatic ${\alpha}-amylase$ in vitro test. The extents of hydrolysis were 64.5% and 59.3% in native and acetylated potato starch, 70.5% and 60.4% in native and hydroxypropylated corn starch, and 65.2% and 57.3% in native and hydroxypropylated high amylose corn starch, respectively. The hydrolysis extents of waxy corn starch derivatives were shown in the descending order of pregelatinized (74.3%)>native (72.1%)>acetylated (66.5%)>acetyl distarch adiphate (56.4%)>hydroxypropyl distarch phosphate (50.7%). In the test on starches of container and regular ramen cooked by practical way, no significant difference was observed between ramen products of five different makers. Although the hydrolysis rate and extent of chemically modified starches were lower than those of native starches, the digestibility of ramen seemed to be not affected in the common diet as the use level of modified starch was relatively low.

• Journal of The Korean Society of Grassland and Forage Science
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• v.12 no.3
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• pp.178-184
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• 1992

Five varieties of silage corn were cultivated to compare the growth characteristics and productivity. Corn varieties were Pioneer 3144(P 3144), 3160(P 3160), 3282(P 3282), 3352(P 3352) and Suweon 19 (S 19). The corns were seeded on May 2 and harvested on August 15, and measured the plant height, leaf length, leaf width, stem diameter, and yields of fresh and dry matter. The results obtained were as follows: 1. Plant height of P 3352 and P 3144 grown about 280cm throughout the experimental period was the tallest(P<.Ol), and those of P 3160, P 3282 and Suweon 19 ranged from 246.3 to 256.0 cm. 2. Leaf length is the longest in P 3352 and the shortest in P 3282(97.63cm vs 84.17cm), and there was significant(P<.Ol) difference between corn varieties. 3. Stem diameter was the longest in P 3144 and the shortest(P<.Ol) in P 3352(3.28cm vs 2.66cm). 4. P 3144, P 3282 and P 3352 had the greatest(P<.Ol) fresh matter yields per 10a in leaf, stem, and ear and whole plant, respectively. 5. Dry matter yield of P 3282 was the greatest(P<.Ol) in stem(1,080.6 kg/lOa) and leaf(304.5 kg/lOa), and that of P 3352 was the greatest in ear(864.1 kg/lOa) and whole plant yield(2,021 kg/lOa). 6. Ratios of respective part of corn to total dry matter were ranged from 12.7 to 17.8 76 for leaf, 44.5 to 66.9% for stem and husks, and 16.9 to 42.8 % for ear, and the highest in P 3160, P 3160 and P 3352, respectively. Consequently, P 3352, P 3144 and P 3282 shown high productivity in dry matter yield could be recommended as a reliable corn varieties for silage.

• Korean Journal of Food Science and Technology
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• v.47 no.2
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• pp.149-157
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• 2015

The effects of feed moisture content (25, 35, and 45%), screw speed (230, 250, and 270 rpm), and barrel temperature (130, 140, and $150^{\circ}C$) on the product yield and soluble arabinoxylan (SAX) content from destarched corn fiber (DCF), and its optimization were investigated. The yield and SAX content of corn fiber gum (CFG) from the extruded destarched corn fiber (EDCF) were higher than those of DCF. Statistical analyses revealed that the feed moisture content and barrel temperature had a significant effect on the CFG yield and total SAX content. The optimum extrusion pretreatment conditions were as follows: feed moisture content, 30%; screw speed, 260 rpm; barrel temperature, $133^{\circ}C$. This study showed that the response surface methodology was suitable for the optimization of the extrusion conditions used to maximize the CFG yield and total SAX content from EDCF.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.5
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• pp.381-387
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• 2003

Winter hairy vetch (HV) can be used as green manure with conventional tillage system (CT), in which chemical N fertilizer required for cultivation of sub-sequent com could be fully saved, or as cover crop with no-tillage system (NT) in which soil could be protected from erosion, control of weed, and the reduction of N fertilizer application. This experiment was carried out to compare the enrichment of soil mineral nitrogen (SMN) at corn root zone, and the changes of com growth and N uptake according to HV amounts (winter fallow, above-ground HV removed, intact HV, and HV added from aboveground HV removed) under two tillage systems in the upland field of National Crop Experiment Station, Suwon, Korea in 1996. HV cultivation during winter decreased SMN a little at com planting. HV incorporation with CT increased SMN rapidly during early growth stage according to rapid decomposition of Hv. SMN by HV cover with NT was increased slowly and its increase was higher in the surface soil (soil layer 0-7.5cm) compared to deep soil layer 7.5-22cm. Com growth and N status at corn silking stage, com yield and N uptake at harvest were increased in proportion to aboveground HV amounts regardless of tillage system. Average hairy vetch nitrogen (HV-N) uptake efficiency by com was 10% higher with CT than with NT in which average HV-N uptake efficiency was 43 %. Corn yields were not different between two tillage systems, but corn N uptake was increased by 33 kgN/ha more with CT than with NT due to the increase of corn N concentration. The increase of SMN and com N uptake from HV cover with NT could not be disregarded though those with CT were higher than with NT

• Korean Journal of Food Science and Technology
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• v.23 no.3
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• pp.317-324
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• 1991

Gelatinization behaviours and gel properties of hydroxypropylated corn starches (HPCS) were investigated with differential scanning calorimeter, amylograph and rheometer. Gelatinization temperature of HPCS decreased as degree of substitution increased. The retrogradation of corn starch was greatly reduced by hydroxypropylation, indicating that the association of starch molecules was sterically hindered by hydroxypropyl groups. In HPCS, gel was formed slowly and gel strength decreased resulting in soft and sticky texture. Texture profiles of HPCS gels were similar to those of tapioca and waxy corn starch. HPCS has shown a remarkable increase of paste transparency compared to native corn starch.

• Journal of The Korean Society of Grassland and Forage Science
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• v.18 no.2
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• pp.107-112
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• 1998

This experiment was carried out to investigate effects of herbicide application method on Abutilon avicennae control and corn yield at the forage experimental field, grassland and forage crop division, National Livestock Research Institute, RDA, Suwon from 1996 to 1997. The experiment was arranged in a randomized block design with three replication. The herbicide application consisted of control, 2-3 leaf stage(Dicamba), 5-6 leaf stage (Dicamba) and soil treatment(Pendimetha1in). The hybrid of corn used in this experiment was P 3352. The results obtained are summarized as follow; 1. The plant and ear height was the lowest at control. Tasseling and silking date were delayed 3-4 day at control. The length and weight of ear were the highest at Dicamba treatment in 2-3 leaf stage. 2. The herbicide injury of corn was detected slightly after 10-20 day but the injury was recovered soon. The weed control efficiency was 96.7 and 81.8% at Dicamba treatment in 2-3 and 5-6 leaf stage, respectively. 3. The fresh and dry matter yield of Dicamba treatment in 2-3 leaf stage was higher than that of control by 36%, but no significant difference was found among herbicide application method. 4. Herbicide application method had little effect on the ADF, NDF and CP contents, but the CP and IVDMD of ear were higher than that of stover. The results of this experiment indicate that the application of Dicarnba in 2-6 leaf stage of corn will remove almost all of A butilon avicennae and increase DM yield of corn.

• Journal of The Korean Society of Grassland and Forage Science
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• v.37 no.3
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• pp.216-222
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• 2017

This study was conducted to examine the effect of corn (Zea mays L.) - soybean (Glycine max L.) silage prepared by intercropping method on the nutritive value of the silage, in vitro rumen fermentation characteristics, dry matter degradability, as well as milk yield and milk composition of dairy cows. In a couple of experiments intercropped corn-soybean silage (CSBS) was compared with corn silage (CS) and/or Italian ryegrass hay (IRG). Numerically, CSBS had higher crude protein, ether extract, and lactic acid contents compared to CS. In vitro rumen fermentation analysis demonstrated that up to a 24-h incubation period, both CS and CSBS showed higher total gas production, ammonia N concentration, and dry matter degradability compared to IRG (p<0.05). The investigation on animals was conducted in a commercial dairy farm located in Gyeongju, South Korea, employing 42 Holstein cows that were divided into 2 group treatments: CS and CSBS in a completely randomized design. Although no significant difference was observed in milk yield, animals fed on CSBS showed significantly higher milk protein (p<0.05) and milk fat content (p<0.01), compared to animals fed on CS. Taken together, our findings indicate that corn-soybean silage that is cultivated, harvested, and prepared through intercropping can improve the protein content of the silage, and can also enhance in vitro rumen fermentation, dry matter degradability, and performance of dairy cattle.