• The Korean Journal of Food And Nutrition
• /
• v.28 no.4
• /
• pp.586-593
• /
• 2015

The baking properties of gluten-free rice bread with different percentages of corn starch and waxy corn starch were investigated. The specific gravity and color (L, a, b) of the dough as well as the appearance, color (L, a, b) and texture of the rice bread were analyzed. Replacement of rice flour with 1, 2.5, 5, 7.5 and 10% corn starch did not have a significant effect on the specific gravity and color of the dough. The volume and specific volume of the rice bread showed an increasing trend as the amount of added corn starch increased. The chewiness, gumminess and hardness of the rice bread showed a decreasing trend as the amount of added corn starch increased. Replacement of rice flour with 1, 5 and 10% waxy corn starch did not have a significant effect on the specific gravity and color of the dough. The color of the rice bread showed an increasing trend as the amount of added waxy corn starch increased. These results suggest that replacement of rice flour with 7.5% corn starch or 1% waxy corn starch is effective for gluten-free rice bread.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.26 no.3
• /
• pp.436-442
• /
• 1997

Corn starch was extruded under relatively low shear, high moisture, and low temperature. Puffing of corn starch dough was induced by injecting $CO_2$gas in the range from 0MPa to 0.09MPa. Piece density and compressive modulus for puffed corn starch were decreased by increasing the injection pressure to 0.07MPa, and increased above 0.07MPa. the microstructure of corn starch puffed with $CO_2$gas showed thick cell size, compared with those puffed with steam. RVA paste viscosity curves of corn starch puffed with $CO_2$had different patterns from those puffed with steam, probably resulted from partial gelatinization of starch. Water absorption and solubility were not significantly changed by $CO_2$injection pressure, but the average degree of polymerization was reduced by higher $CO_2$injection. The water absorption, water solubility, and the average degree of polymerization for corn starch puffed with $CO_2$were significantly lower than those puffed with steam.

• Korean Journal of Food Science and Technology
• /
• v.27 no.3
• /
• pp.428-438
• /
• 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 Food Science and Technology
• /
• v.39 no.2
• /
• pp.169-174
• /
• 2007

In this study, we examined the characteristics of alkali gelatinization of corn starch. Here, the degree of corn starch gelatinization increased exponentially with the NaOH concentration of the starch slurry. The alkali gelatinization initiation point (AGIP) was obtained from the intersection point of gelatinization slope line, which resulted from the regression of the logarithmic degree of gelatinization, and was markedly changed. The effects of temperature and corn starch concentration on alkali gelatinization were studied with a 10%(w/w) corn starch suspension. We found that this corn starch suspension gelatinized in 24.1 meq/g starch of NaOH at $40^{\circ}C$, and in 9.8 meq NaOH/g starch at $60^{\circ}C$. Moreover, a 40%(w/w) corn starch suspension gelatinized with 9.5 meq NaOH/g starch, even at $40^{\circ}C$. These results indicate that the amount of alkali added for the gelatinization of corn starch has an inverse relationship with the temperature and concentration of corn starch.

• Food Science and Industry
• /
• v.51 no.1
• /
• pp.45-60
• /
• 2018

The starch industry in Korea had been based on sweet potato and potato for long time to produce starches which were used for mainly starch noodle such as cellophane noodle. Because of the poor storage stability, high price, and fluctuation of production by year and year of potatoes, the raw material for the production of starch had been changed to corn in 1970s. Along with this, the mass production system had been established, which enabled the production of various starch-related products including modified starches for food, textile, paper, and other industrial uses, starch sweetners, high fructose corn syrup, and gelatinized starch. In this paper, a brief background of corn industry in Korea has been described. The production of starch from corn has been emphasized and the future of corn industry in relation with GMO has been suggested.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.45 no.4
• /
• pp.52-64
• /
• 2013

This study was carried out to investigate the characteristics of starch paste which was used for the conservation of paper properties. Three kinds of commercial corn starch and five kinds of fermented wheat starch were examined on the contents of amylose and amylopectin, shapes of particles, and viscosity and pH of paste. And adhesive strength on the drying, accelerated aging, and wetting treatments were measured. The contents of amylopectin of oxidized corn starch were higher those of cationic corn starch, unmodified corn starch, and fermented wheat flour. In case of fermented wheat flour, increasing of a fermentation period was resulted in increasing of amylopectin contents. The particle shapes of commercial corn starch showed with a uniform polygon, but fermented wheat flour showed with a mixture of small and large oval types. The viscosity of oxidized corn starch were very lower those of cationic corn starch and unmodified corn starch. And increasing of a fermentation period of wheat flour was resulted in increasing of viscosity. The pH of commercial corn starch were 3.6-7.5 and fermented wheat flour were 3.6-5.2. Through the examination on the nature and adhesive strength of starch paste, the oxidized corn starch 60 cps which is the name of products and wheat flour which had fermented for 5 years were considered that most suitable for conservation of paper properties.

• Korean journal of food and cookery science
• /
• v.12 no.1
• /
• pp.1-5
• /
• 1996

The effects of defatting on sensory and instrumental characteristics of corn and mung bean starch gels during storage were investigated. The untreated and defatted starch gels stored at room temperature for 24 hrs and 72 hrs. The sensory characteristics of defatted corn starch gels were significantly different from untreated ones but the properties of defatted corn starch gels were similar to those of mung bean ones. Mung bean starch gels showed no changes in sensory characteristics by defatting. In the case of instrumental properties, there was highly significant in all characteristics between corn starch gels and mung bean starch gels, but firmness in defatted corn starch gel was similar as in mung bean starch gels.

• Journal of Food Hygiene and Safety
• /
• v.14 no.1
• /
• pp.84-89
• /
• 1999

Octenylscuccinated corn starches prepared by reaction of corn starch with 1-octenylsuccinic anhydride(OSAn) and their degree of substitution (DS), reaction efficiency(RE), residual octenylsuccinic acid (OSA), and physicochemical properties were compared with those of the native corn starch. DS increased with increase of OSAn and RE was much nearly the same regardless of increased of OSAn. The content of residual of residual OSA was significantly lower than that of regulation of food additives. And as washing frequency of dispersion of the reactant was increased, the content of residual OSA of octenylsuccinated starch was decreased. Raid Visco-Analyzer initial pasting temperature and setback of octenylsuccinated starches decreased whereas peak viscosity and breakdown increased. When DS of octenylsuccinated starches increased, temperature of initial gelatinization of octenylscuccinated starches drastically decreased. The octenylsuccinated starches also formed clearer pastes. The solubility was much nearly the same regardless of increase of DS at 7$0^{\circ}C$ but the swelling power increased 1.2~1.7 times higher than that of native corn starch at 7$0^{\circ}C$. The water binding capacity of octenylsuccinated starches also decreased.

• Journal of the East Asian Society of Dietary Life
• /
• v.10 no.5
• /
• pp.431-438
• /
• 2000

The physical and processing properties of acorn jelly were investigated to see the effect of polysaccharides in seaweed extract and corn starch. The yield of acorn jelly added starch concentration was slightly increased when the concentration was added more. However, moisture content and color had no significant changes with concentration. In the case of acorn jelly added sea tangle, color of acorn jelly was darker, but color of the jelly with carrageenan was lighter. According to the concentration of seaweed extract, the hardness was increased as concentration was added. The texture of acorn Jelly added agar had the highest binding. In the case of acorn jelly added corn starch, there were no significant changes, but this binding was stronger than the acorn jelly added extract of marine algae. In the physical and sensory properties of acorn jelly with corn starch, the ideal mixture ratio between the acorn jelly and the corn starch was 6:4.

• Preventive Nutrition and Food Science
• /
• v.2 no.1
• /
• pp.23-28
• /
• 1997

Physicohemical properties of corn starches isolated from non-glutinous and corn grains fol-lowing γ-irradiation up to 10kGy were investigated. Blue value, water binding capacity and swelling power decreased, while alkali number ad solubility increased by γ-irradiation , which was more pronounced in glu-tinous corn starch than in non-glutinous corn starch. The optical transmittance increased with an increment of heating temperature and applied irradiation doses. No significant difference was observed in Hunter's color value between both starches isolated from non- irradiated and irradiated and irradiated corn grains. Amylograph viscosities decreased remarkably as dose levels increased. The overall effects of γ-irradiation was more distinguished in glutinous starch than in non-glutinous starch.