• Korean Journal of Food Science and Technology
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• v.27 no.3
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• pp.428-438
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• 1995

The gelatinization properties of corn and waxy corn starch doughs were examined at various moisture contents, heating temperatures and heating times. The onset temperatures of gelatinization with 1% CMC using Brabender Amylograph were $64^{\circ}C$ for both corn and waxy corn starch. In the gelatinization properties using DSC, onset temperature$(T_o)$, maximum peak temperature$(T_p)$, completion temperature$(T_c)$ and enthalpy of the corn starch were $68.15^{\circ}C,\;74.01^{\circ}C,\;85.65^{\circ}C$ and $3.2\;cal/gram$ respectively. While those of the waxy corn starch were $68.24^{\circ}C,\;75.43^{\circ}C,\;93^{\circ}C$ and $4.2\;cal/gram$ respectively. In enzymatic analysis, when the moisture content increased from 36% to 52% and heating temperature from $60^{\circ}C$ to $100^{\circ}C$, the gelatinization degree of starch dough increased from about 10% to about 62%. The gelatinization degree of waxy corn starch dough was $15{\sim}20%$ higher than that of corn starch dough under the same gelatinization conditions. The regression equations of gelatinization degree (Y) of starch dough in the range of $36{\sim}52%$ moisture content $(X_1)\;60{\sim}100^{\circ}C$ heating temperature $(X_2)\;and\;0{\sim}2.0$ min heating time $(X_3)$ were examined using response surface analysis. The regression equation of corn starch dough was: $Y=28.659+8.638\;X_}+15.675\;X_2+7.770\;X_3-1.620\;{X_1}^2+10.790\;X_1X_2-4.220\;{X_2}^2+0.510\;X_1X_3+1.980\;X_2X_3-6.850\;{X_3}^2\;(R^2=0.9714)$ and that of waxy corn starch dough was: $Y=32.617+12.535\;X_1+20.470\;X_2+8.608\;X_3+4.093\;{X_1}^2+13.550\;X_1X_2-4.467\;{X_2}^2+1.560\;X_1X_3+2.160\;X_2X_3-9.527\;{X_3}^2$\;(R^2=0.9621)$. As the moisture content, heating temperature and heating time increased, the reaction rate constant(k) of gelatinization increased. The greatest reaction rate constant was observed at initial 0.5 min heating time of 1st gelatinization stage. At the heating temperature of $90^{\circ}C$, gelatinization of starch dough was completed almost in the initial 0.5 min heating time. The reaction rate constant of waxy corn starch dough was higher than that of corn starch dough under the same gelatinization conditions. At the 52% moisture content, the regression equation between reaction rate constant(k) and heating temperature(T) for corn starch dough was $log\;k=11.1140-4.1226{\times}10^3(1/T)$ (r=-0.9520) and that of waxy corn starch dough was $log\;k=10.1195-3.7090{\times}10^3(1/T)$ (r=-0.9064).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.3
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• pp.189-194
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• 2001

It is possible to use hairy vetch as green manure for corn not only in corn single cropping but also in double cropping system of corn and fall oats. Fall oats and hairy vetch were mixed-sown after corn harvest and harvested as forage in the early of November, and then hairy vetch stubble was over-wintered and incorporated into soil at corn planting as green manure without N fertilizer (FO+HV-GM). Other treatments were fall oats without N fertilizer on corn (FO-0N) and with N fertilizer 200kg/ha on corn (FO-200N), hairy vetch green manure without N fertilizer on corn (HV-GM), and fell winter follow without N fertilizer on corn (WF-0N). Soil nitrate content, corn growth and nitrogen uptakes, and yield of corn were measured and compared during 2-year experimental seasons. Dry matter and N amount of hairy vetch at the plot of FO+HV-GM were 60% less than those at the plot of HV-GM. The N effect of hairy vetch green manure on corn at the plot of HV-GM was similar to that at FO-200N plot for two years. Soil nitrate at the plot of FO+HV-GM was below the half of those at plots of HV-GM and FO-200N at 6-leaf stage of corn. N uptake of corn at the plot of FO+HV-GM at silking stage was 30% less than those at plot of HV-GM and FO-200N. However, soil nitrate at 6-leaf stage of corn and the amount of nitrogen uptake of corn at silking stage increased two times and 30-40 kg/ha, respectively, compared with those at the plot of FO-0N. Corn yield at FO+HV-GM decreased about 2 ton/ha due to the decrease of corn grain weight in the first year compared with plot of HV-GM and FO-200N, but its difference was not shown in succeeding second year. Corn N uptake at FO+HV-GM decreased 60 kg/ha and 20 kg/ha in 1999 and 2000, compared with plot of HV-GM and FO-200N, respectively, but increased 30kg/ha and 45kg/ha compared with the plot of FO-0N in 1999, 2000, respectively. Therefore, it is estimated that hairy vetch green manure in fall oats-corn double cropping system can reduce nitrogen chemical fertilizer on corn as much as 50-100 kg/ha although its N effect is much lower than the N effect of hairy vetch green manure in corn single cropping of which N effect is over 200 kg/ha.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.4
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• pp.272-275
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• 2000

Winter green manure crops including legume increase grain yield of subsequent crop and substitute N fertilizer requirement with organic-No Hairy vetch grows vigorously and can provide N-rich green manure for corn with its soil incorporation after wintering. But, grain yield of corn as succeeding crop would be reduced if its planting time is delayed until late spring. This experiment was carried out to find the proper incorporation time of hairy vetch green manure and planting time of subsequent corn in cropping system with winter hairy vetch(green manure)-summer corn. Hairy vetch was incorporated into soil at a ten-day interval between April 10 and May 10 and corn was planted at 5 days after each hairy vetch incorporation. Soil nitrate concentration on April 10 and 20 in hairy vetch plot was slightly lower than that at winter fallow. Above-ground dry matter and organic-N of hairy vetch increased linearly with delayed hairy vetch incorporation time from April 10 to May 10. Average dry matter and organic-N produced by hairy vetch were 5.7 ton/ha and 248 kgN/ha, respectively. Corn growth and yield decreased as delayed corn planting time after May in spite of increasing dry matter and N-yield of hairy vetch. Nitrogen concentration of corn grain, stalk and whole plant at harvest were the highest in May 5 planting, but total N-uptake of May 5 planting were not different from that of April 25 planting because of lower grain yield. It was concluded that the proper incorporation time of hairy vetch and corn planting time were April 20 and April 25, respectively, because grain yield was the highest and corn could use hairy vetch-N effectively to produce dry matter.

• Asia-Pacific Journal of Business
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• v.8 no.1
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• pp.45-65
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• 2017

This study which focused on factors and challenges affecting the decision-making of indigenous corn farmers ascertained the determinants that make farmers decide to engage in and continue corn farming activities in Paracelis, Mountain Province, in Northern Philippines. Determinants of decision and motivational factors of corn farmers were examined based on survey responses of 120 indigenous corn farmers by applying chi-square test analysis. Results showed that there were some decision and motivational factors that were significantly related to specific characteristics of corn farmers and there were also similarities of factors that affected the decision making of farmers in terms of engaging in and sustaining corn farming activities. Among the identified driving forces, financing capability and availability of land area were highly related with farm size and with a farmer's educational attainment. Knowledge or experience and interest in corn farming were also related with educational attainment. All the identified driving forces were found to be unrelated to farmers' age. The motivational factor identified as "personally satisfying" was found to be related with age, educational attainment and years in the farming business. Factors which affected a farmer's decision to sustain corn farming activities ("sustaining" factors) such as availability of different networks is highly related to educational attainment, years in the farming business and farm size while high market price of corn was the only "sustaining" factor linked to educational attainment. Based on these factors and cited problems in corn farming, recommendations were offered to address the issues raised by farmers.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.7
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• pp.977-983
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• 2009

The survival and effect of three new probiotic inoculants (Lactobacillus plantarum CCM 4000, L. fermentum LF2, and Enterococcus faecium CCM 4231) on the nutritive value and fermentation parameters of corn silage was studied under laboratory conditions. Whole corn plants (288.3 g/kg DM) were cut and ensiled at $21^{\circ}C$ for 105 days. The inoculants were applied at a concentration of $1.0{\times}10^{9}$ cfu/ml. Uninoculated silage was used as the control. The chopped corn was ensiled in 40 plastic jars (1 L) divided into four groups (4${\times}$10 per treatment). All corn silages had a low pH (below 3.55) and 83-85% of total silage acids comprised lactic acid after 105 days of ensiling. The probiotic inoculants in the corn silages affected corn silage characteristics in terms of significantly (p<0.05-0.001) higher pH, numerically lower crude protein content and ratio of lactic to acetic acid compared to control silage. However, the inoculants did not affect the concentration of total silage acids (acetic, propionic, lactic acids) as well as dry matter digestibility (IVDMD) of corn silages in vitro. In the corn silages with three probiotic inoculants, significantly (CCM 4231, CCM 4000) lower n-6/n-3 ratio of fatty acids was detected than in control silage. Significant decrease in the concentration of $C_{18:1}$, and significant increase in the concentration of $C_{18:2}$ and $C_{18:3}$ was mainly found in the corn silages inoculated with the strains E. faecium CCM 4231 and L. plantarum CCM 4000. At the end of ensiling, the inoculants were found at counts of less than 1.0 log10 cfu/g in corn silages.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.1
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• pp.80-85
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• 2018

Objective: This study was conducted to investigate the effect of corn grain particle size on ruminant fermentation and blood metabolites in Holstein steers fed total mixed ration (TMR) as a basal diet to explain fundamental data of corn grain for cattle in Korea. Methods: Four ruminally cannulated Holstein steers (body weight $592{\pm}29.9kg$) fed TMR as a basal diet were housed individually in an auto temperature and humidity modulated chamber ($24^{\circ}C$ and 60% for 22 h/d). Treatments in a $4{\times}4$ Latin square design were TMR only (control), TMR with whole corn grain (WC), coarsely ground corn grain (CC), and finely ground corn grain (FC), respectively. The corn feeds substituted for 20% energy intake of TMR intake. To measure the ruminal pH, ammonia N, and volatile fatty acids (VFA), ruminal digesta was sampled through ruminal cannula at 1 h intervals after the morning feeding to determine ruminal fermentation characteristics. Blood was sampled via the jugular vein after the ruminal digesta sampling. Results: There was no difference in dry matter (DM) intake between different corn particle size because the DM intake was restricted to 1.66% of body weight. Different corn particle size did not change mean ammonia N and total VFA concentrations whereas lower (p<0.05) ruminal pH and a ratio of acetate to propionate, and higher (p<0.05) propionate concentration were noted when the steers consumed CC compared with WC and FC. Concentration of blood metabolites were not affected by different particle size of corn grain except for blood triglyceride concentration, which was significantly (p<0.05) increased by FC. Conclusion: Results indicate that feeding CC may increase feed digestion in the rumen, whereas the FC group seemed to obtain inadequate corn retention time for microbial degradation in the rumen.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.3
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• pp.379-385
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• 2004

Two trials in vivo and in vitro were conducted, in vivo to determine the apparent digestibility of gross energy, crude protein, dry matter, acid detergent fiber, neutral detergent fiber and apparent digestible energy in 10 corn by-products. In vivo the diets included one basal corn diet, four corn gluten meal diets, four corn distillers dried grains with solubles diets and two corn distillers dried grains diets using the different methods, 12 crossbred barrows weigh $40{\pm}$1.6 kg were allocated into individual metabolic crate, according to a $6{\times}6$ Latin square design. In vitro using flask technique, filter bag technique and dialysis tubing technique, the digestibilities of gross energy, crude protein and dry matter in corn gluten meal and corn distillers dried grains with solubles were investigated. Pepsin, pancreatin, intestinal fluid, rumen fluid and cellulase were used in incubation. The results showed that correlation coefficient was 0.73 in corn distillers dried grains with solubles between the digestibility of crude protein and acid detergent fiber in vivo (p<0.01); and correlation coefficient was 0.68 in corn distillers dried grains with solubles between the digestibility of gross energy and neutral detergent fiber in vivo (p<0.01). Apparent digestible energy (DE) of corn by-products in pig total tract was predicted by the percentage of crude protein (CP) and the content of gross energy (GE) in feedstuff. The equation: DE=5,601.09+26.69$\times$CP %-0.5904$\times$GE, ($R^2=0.72$). In vitro, filter bag technique was more convenient; furthermore, the digestibility for the treatments (pepsin+pancreatin+rumen fluid and pepsin+pancreatin+cellulase) was better.

• Current Research on Agriculture and Life Sciences
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• v.32 no.2
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• pp.105-109
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• 2014

The soybean [Glycine max (L.) Merr.], an edible legume, has a high protein content in both its hay and grain, so it is often used as a supplement for other forages that have a deficient protein concentration. Therefore, this study investigated the forage quality and yield in the case of mixed planting of soybean and corn. The forage yield and quality were assessed for three cropping patterns: soybean mono planting, corn mono planting, and mixed planting of soybean and corn. For planting, this study used a forage corn cultivar, Kwangpyeongok, and three recombinant inbreed lines, W2, W4, and W11, selected from Glycine soja (PI483463)${\times}$G. max (Hutcheson). The mixed planting of soybean and corn produced a higher forage yield than the corn mono cropping. The crude protein and crude fat content were also increased with the mixed planting of soybean and corn when compared with the corn mono cropping. Some decrease of ADF and NDF, and increase for RFV in mixed planting of soybean and corn than corn mono cropping. Therefore, the results show that mixed planting of soybean and corn is an effective cropping system to improve the forage quality.

• Korean Journal of Food Science and Technology
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• v.13 no.1
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• pp.53-56
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• 1981

Several tests were conducted to study lipoxygenase activity and off-flavor developement in frozen sweet corn. Fresh corn contained about 60% of total lipoxygenase activity in the germ section. When non-blanched frozen sweet corn was stored at $-10^{\circ}F$, it developed off-flavor and most significant changes in the flavor profile of off-flavored sweet corn was $4{\sim}5$ times higher hexanal peaks. The high hexanal peaks observed in the sterilized sweet corn with added lipoxygenase, alone and in combination with other enzymes, suggested the fact that high hexanal peaks in off-flavored sweet corn could be due to an oxidative reaction of lionleic acid (and other unsaturated fatty acids) catalyzed by lipoxygenase. Based on lipoxygenase activity and linoleic acid content in sweet corn, this reaction occur most heavily in the germ section of sweet corn. There was a significant relationship between flavor score of frozen stored corn-on-the-cob and hexanal peak in the germ section of corn-on-the-cob. This result indicated that hexanal peak could be used as an objective index of off-flavor development in frozen sweet corn.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.5
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• pp.694-699
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• 2005

The aim of this study was to develop muffins in which corn bran fiber was substituted 10, 30, 50 or $70\%$ for fat and the quality characteristics were compared with a full-fat counterpart. The volume and height of muffin was highest in control and decreased with increasing corn bran fiber content, but no difference in weight was observed (p<0.05). The incorporation of corn bran fiber in the product lowered lightness and redness values but decreased yellowness values. The mechanical texture parameters including hardness, springiness, gumminess and brittleness increased with increasing corn bran fiber levels. Scanning electron microscope showed that the size of air cells was decreased with increasing corn bran fiber levels. Sensory analysis yielded muffin with $30\%$ substitution of butter with corn bran fiber was considered to be as acceptable as control.