• Korean journal of food and cookery science
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• v.33 no.1
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• pp.28-36
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• 2017

Purpose: This study was conducted to understand the factors that affect the texture of gluten-free rice pasta prepared buckwheat, mung bean, and acorn starches and to compare textural properties of samples 100% semolina. Methods: The moisture content, weight and water absorption test investigated and texture profile analysis measured by texture analyzer. Results: 100% semolina sample's value was lower than gluten-free rice pasta moisture content, weight and water absorption test. moisture content weight was in pasta with mung bean starchin pasta with buckwheat starch. Texture profile analysis showed that increasing amount of buckwheat, mung bean, and acorn starches increased hardness, chewiness, cohesiveness and springiness, and decreased adhesiveness of gluten free rice pasta. Conclusion: This study suggested that adding buckwheat, mungbean and acorn starches could improve texture properties of gluten-free rice pasta.

• Culinary science and hospitality research
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• v.22 no.7
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• pp.100-111
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• 2016

Tomato sauce were prepared with five different thickening agents including roux (TR), non-glutinous rice powder (TN), glutinous rice powder (TG), potato starch (TP) and tapioca starch (TT) to examine proximate composition (moisture, carbohydrate, crude protein, crude fat, crude ash, crude ash), calorie, color value, pH, salinity, $^{\circ}Brix$, reducing sugar, viscosity and sensory test (attribute difference, acceptance). The results were as follows: Moisture, carbohydrate content were the lowest while crude fat and calorie were the highest in TR (roux). On the other hand, moisture, carbohydrate content were the highest while crude protein, crude fat and calorie were the lowest in TP (potato starch) and TT (tapioca starch). Using potato starch and tapioca starch are supposed to be prepared low-fat, low-calorie tomato sauce. L value was the highest in TN (non-glutinous rice powder), a value was the highest in TP (potato starch), b values was the highest in TR (roux). pH of tomato sauce showed a range of 5.24 to 5.39. TG (glutinous rice powder) was the highest and TT (tapioca starch) was the lowest in pH. TP (potato starch) was the highest salinity, reducing sugar was the lowest. TG (glutinous rice powder) was the lowest salinity, $^{\circ}Brix$ was the highest. And TR (roux) was the lowest $^{\circ}Brix$, reducing sugar was the highest. In viscosity, TG (glutinous rice powder) was the highest and TT (tapioca starch) was the lowest. The attribute difference test results was the highest in gloss, color intensity, tomato odor, tomato taste, pure taste in TT (tapioca starch) and savory taste, oily taste, thickness, residue was the highest in TR (roux). The preference test results reveal that the appearance, flavor, taste, texture and overall acceptance level was the highest in TP (potato starch) and TT (tapioca starch). The results of this study, tomato sauce prepared potato starch and tapioca starch instead of the traditional roux was higher in sensory acceptability. Recently, people is avoided high-fat and high-calorie foods, and potato starch and tapioca starch are confirmed that the tomato sauce can be made of a low-fat and low-calorie.

• Applied Biological Chemistry
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• v.36 no.6
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• pp.533-538
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• 1993

The Wx protein, known as starch synthase or starch glucosyl transferase (E.C. 2.4.1.11), is responsible for the amylose synthesis. In an effort to explain the mechanism of amylose biosynthesis, the starch synthase known as Wx protein was identified by analyzing the various wx rice mutants with SDS-PAGE of proteins extracted from rice starch. Finally, the 66 kDa protein was purified by extracting the starch-bound protein fractions followed by Suprose 12 gel filtration chromatography.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.2
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• pp.35-46
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• 2023

The transplanting period limit considering the rice yield in the Dague region, the inland plains of Gyeongsangbuk-do, was estimated to be July 15^th for early and mid-maturing rice and July 5^th for mid-late maturing rice. However, as the transplanting time was delayed, the characteristics of rice starch changed significantly. In the case of early and mid-maturing rice varieties, the starch granule size increased as the transplanting time was delayed; the opposite tendency was observed for mid-late maturing varieties. In all mature rice types, the late transplanting resulted in a longer pasting time and a higher pasting temperature. In addition, the peak viscosity, breakdown, and gelatinization temperature were significantly lowered, the relative crystallinity degree decreased, and the setback was significantly increased. In the case of Ilpum, a mid-late maturing rice variety, the distribution of amylopectin short chains tended to increase when rice was transplanted on June 30^th.

• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.776-782
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• 1995

The effects of alum$(Al{\cdot}K(SO_4)_2{\cdot}12H_{2}O)$ on the rheological properties of $3{\sim}9%(w/v)$ gelatinized solutions of nonwaxy and waxy rice starches were investigated to evaluate the possibility of utilizing a starch modifying agent. Gelatinized non-waxy and waxy rice starch solutions showed a pseudoplastic flow behavior with yield stress. Pseudoplasticity of two rice starch solutions increased by the addition of alum$(0.05{\sim}1.0%,\;w/w)$. Alum increased the yield stresses and consistency indexes of two rice starches and these values decreased with increasing starch concentration. Also, alum(0.5%, w/w) increased the flow activation energy of gelatinized waxy rice starch solution and activation energy decreased with increasing waxy rice starch concentration in the range of $3{\sim}7%(w/v)$, but for the nonwaxy rice starch, activation energy decreased at starch concentration of 7%(w/v). From the above results, it was found that alum had the possibility of utilizing a modifying agent for the rheological property of gelatinized starch solution.

• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.939-946
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• 1997

Effects of moisture content on the gelatinization and recrystallization of non-waxy and waxy rice starch gels were investigated by differential scanning calorimetry (DSC). The recrystallization rates of the starch gels containing various moisture contents $(40{\sim}70%)$ were analyzed by Avrami equation. The waxy rice starch had higher gelatinization temperature and enthalpy than non-waxy one. The highest degrees of recrystallization in both rice starch gels stored at $4^{\circ}C$ were shown at 40%, and recrystallizations above 80% moisture content were not found. The degree of recrystallization of waxy one was higher than that of non-waxy one in the range of 40 to 60% moisture content. The Avrami exponents (n) of both rice starch gels were near to 1.0 and the time constant (1/k) was increased with increasing moisture content in the range of 40 to 70% moisture content. The recrystallization rate of waxy rice starch gel was slower than that of non-waxy one. The recrystallization of rice starch gels could be explained by the change of ice melting enthalpy during storage. The Wg's, represented the maximum practical amount of plasticizing water, were about 29.9% and 28.2% for non-waxy and waxy rice starch gels, respectively.

• Korean Journal of Food Science and Technology
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• v.53 no.5
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• pp.514-520
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• 2021

This study identified and quantified the sugar-related metabolites and analyzed the structural features of starch in kimchi added with various concentrations of glutinous rice paste during fermentation. The pH values and total bacterial counts indicated that the fermentation of kimchi with 10% glutinous rice paste progressed more quickly than that of kimchi with other rice paste concentrations. The addition of glutinous rice pastes to kimchi resulted in increased glucose and decreased fructose contents during fermentation compared to the control kimchi. Maltose content increased significantly with increasing glutinous rice paste concentrations. The average chain length distribution of starch in kimchi decreased with increasing proportions of short chains as fermentation progressed. However, the average chain length distribution of starch increased with increasing glutinous rice paste concentration in kimchi. Our results confirmed that the sugar-related metabolites and starch structural changes were highly influenced by the added starch paste concentration.

• Korean Journal of Food Science and Technology
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• v.25 no.2
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• pp.123-129
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• 1993

Physico-chemical properties of the acetylated and raw starch were Investigated with the chucheongbyeo and samkangbyeo. The solubility and swelling power was increased by acylation reaction. The light transmittance was higher in the acetylated rice starch. The blue value of chucheongbyeo and samkangbyeo rice starches were lowered to 10.9% and 16.0%, respectively, by the acylation reaction. The alkali number was 7.6 in the chucheongbyeo rice starch and 7.2 in the samkangbyeo rice starch, whereas acylated starch in the same orders was 55 and 52, respectively. The hardness, adhesion, cohesion of starch gel was increased by the acylation reaction. The temperature of initial gelatinization of the acetylated chucheongbyeo and samkangbyeo rice starch was shown to $59^{\circ}C\;and\;62^{\circ}C$, respectively, lowering $5{\sim}6^{\circ}C$ in temperature by the acylation. The viscosity as well as by the acylation reaction was raised 38% and 14%, respectively. The rice starch particles were shown to plygonal structure. But it were deformed in the acylated starch, and was completely destroyed in the starch which is by gelatinized for 30 min. at $70^{\circ}C$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.3
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• pp.210-218
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• 2018

This study was conducted to examine the influence of different transplanting dates on rice quality and starch properties (morphology and pasting properties) of rice varieties that may be used for the production of rice flour. Three rice flour varieties, 'Seolgaeng', 'Hangaru', and 'Milyang317', were transplanted on May 20, May 30, June 10, and June 20. The peak viscosity decreased with a delay in the transplanting date. However, the amylose content increased with a delay in the transplanting date, whereas that of protein decreased. Amylopectin short-branch chain content increased in the rice varieties that were transplanted on May 30. The morphology of the starch granule of the varieties was determined by SEM. No apparent external difference in the starch granules was observed for the different transplanting dates. These results indicate that the transplanting date influenced the amylopectin structure and pasting properties, which led to changes in the physicochemical characteristics of rice starch.

• Korean Journal of Food Science and Technology
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• v.38 no.3
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• pp.385-391
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• 2006

Physicochemical properties of hydroxypropylated waxy rice starches were investigated to reduce steeping-time of yukwa (Korean oil-puffed rice snack) processing. Swelling power of hydroxypropylated waxy rice starch increased at relatively higher temperature $(60^{\circ}C)$ than native waxy rice starch $(70^{\circ}C)$. Solubility of hydroxypropylated waxy rice starches increased with increasing propylene oxide content. Pasting temperature $(66.3-66.9^{\circ}C)$ and peak viscosity (216-232 RVU) of hydroxypropylated waxy rice starch were higher than those of native starch (179 RVU) and increased with increasing propylene oxide content. DSC thermal transitions of hydroxypropylated waxy rice starches shifted toward higher temperature. Amylopectin melting enthalpy of hydroxypropylated waxy rice starch (8.4-9.2 J/g) was similar to native starch (9.0 J/g). X-ray diffraction patterns of native and hydroxypropylated waxy rice starches showed typical A-type pattern with no significant differences between them, suggesting hydroxypropylation only affected amorphous region. Results suggest hydroxypropylated waxy rice starch is not applicable for yukwa due to low puffing efficiency and dark color.