• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.3
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• pp.277-281
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• 1999

Dull grains segregated from F$_3$ and F$_4$ of the crosses between two dull mutants and a glutinous cultivar were compared with non-glutinous and glutinous segregants for their physicochemical properties. Amylose content of dull rice grain segregated from the dull/glutinous cross showed the intermediate value between glutinous and non-glutinous rice grain, whether it is controlled by the recessive or dominant gene. Alkali digestibility value (ADV) of dull rice grain was lower than that of glutinous or non-glutinous rice. A positive correlation was found between ADV and amylose content of homozygous non-glutinous or dull F$_4$ grains, but a negative relationship was observed in glutinous grains. Protein content of dull grain was significantly higher than that of glutinous or non-glutinous grain segregated from the same cross, while those of glutinous and non-glutinous grains were not different. Among gelatinization characteristics, initial pasting temperature and peak viscosity of dull grains were higher than glutinous rice, and were not different with non-glutinous grain. Hot, cool and consistency viscosities of dull grain were intermediate between glutinous and non-glutinous rices. Dull grains showed the highest breakdown viscosity and the lowest setback viscosity among the three endosperm types.

• Korean Journal of Food Science and Technology
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• v.16 no.2
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• pp.201-205
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• 1984

Some physicochemical properties of ginger root (Zingiber officinale) starch were compared with those of cross-linked corn starch. The ginger root starch that contained 23.5% amylose had a water-binding capacity of 99.1% and a B-type X-ray diffraction pattern. The optical transmittance of the ginger root starch suspension increased from $70^{\circ}C$ and showed a similar pattern to cross-linked corn starch. Solubility studies revealed that both ginger root and cross-linked corn starches had low swelling power and solubility in water up to $90^{\circ}C$, and reduced solubility in potassium hydroxide. Brabender amylograph data indicated that the ginger root starch (7%) had a relatively high initial pasting temperature $(81.5^{\circ}C)$ and was stable against heat and mechanical shear, which resembled to the cross-linked corn starch.

• Korean Journal of Food Science and Technology
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• v.9 no.2
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• pp.138-143
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• 1977

Physicochemical properties of buckwheat starch were investigated. Starch granules were in the range of $4.3{\sim}11.4$ microns in size, the average being 7.8 microns. The starch had a water-binding capacity value of 103.7%, blue value of 0.35 and amylose content of 25%. The initial and final gelatinization temperatures were $61^{\circ}$ and $65^{\circ}C$, respectively. Amylograph data showed that the starch had an initial pasting temperature of $64.5^{\circ}C$. The kinetic study of crystallization of buckwheat starch during aging at $21^{\circ}C$ suggested that the mechanism of starch crystallization is instantaneous nucleation followed by rod-like growth of crystals.

• Korean Journal of Food Science and Technology
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• v.19 no.2
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• pp.97-101
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• 1987

Physicochemical properties of heat-moisture (18, 21, 24 and 27%) treated naked barley (Youngsanbori) starch indicated that crystailinity of the starch was decreased upon treatment and water-binding capacity drastically increased as the moisture level increased. The swelling power was decreased, but the solubility increased by heat-moisture treatment. Apparent viscosity in aqueous sodium hydroxide solution was repressed as moisture-treatment level increased. Amylograph hot paste vicosities were decreased upon treatment except initial pasting temperature.

• 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.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.6
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• pp.778-788
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• 2013

The objective of this study was to investigate the effects and availability of arrowroot powder in making white bread. The characteristics of pasting, farinogram and alveogram of the dough containing arrowroot powder were analyzed. Further, the physicochemical properties of white bread were analyzed by different mixing ratios (0, 3, 5 and 7%) of arrowroot powder during storage periods. When 7% of arrowroot powder was added, the initial pasting temperature of the dough by using a RVA (rapid visco analyzer) was significantly increased. Peak viscosity, holding strength, break down, final viscosity and set back were decreased by increasing added arrowroot powder. With the increasing amounts of arrowroot powder, the values of farinogram and alveogram parameter for the dough showed a tendency to decrement. The texture profile analysis of the white bread revealed that hardness, springiness, cohesiveness and gumminess were increased by adding arrowroot powder and further, the storage time was longer. By increasing the amount of added arrowroot powder, the L value of the white bread was decreased, whereas the a, b value were increased. In the sensory evaluation, the white bread of the control and that of the added 3% arrowroot powder showed the highest preference in total score.

• Korean Journal of Food Science and Technology
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• v.45 no.6
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• pp.747-753
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• 2013

The physicochemical properties of sweet potato (SP) starches reclaimed from an SP-processing sludge without freezing (RC/NF) and with freezing (RC/FR) were investigated. Lab-isolated (LI) SP starch, as a control, were prepared from raw SP. RC/NF and RC/FR SP starches were recovered from SP-processing sludges by the repeated sieving and washing procedure. The total starch contents and amylopectin branch-chain distributions did not differ for three SP starches. Relative to LI and RC/NF SP starches (possessing similar physicochemical characteristics), the apparent amylose and phosphorus contents, swelling factor, and pasting viscosity were reduced for RC/FR SP starch. However, the freezing treatment altered X-ray diffraction pattern (at $5.5^{\circ}$, $11-12^{\circ}$, and $24^{\circ}$ $2{\theta}$) of RC/FR SP starch, which likely increased its gelatinization peak and completion temperatures. Its amorphous region in total diffractogram was reduced, resulting in the enhanced relative crystallinity. Overall results suggested SP starches recovered from an SP-processing sludge would have the potential to replace commercial SP starch products.

• Applied Biological Chemistry
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• v.49 no.1
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• pp.49-54
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• 2006

Physicochemical properties of cross-linked rice starches were investigated. Swelling power of cross-linked rice starch increased at relatively lower temperature $(60^{\circ}C)$ than native rice starch $(70^{\circ}C)$. Cross-linked rice starch showed lower solubility $(1.7{\sim}6.1%)$ than native rice starch $(2.2{\sim}13.8%)$ and solubility is not significantly different with the amount of phosphorus oxychloride. Pasting temperature $(69.2{\sim}70.6^{\circ}C)$ and peak viscosity $(2,874{\sim}3,175\;cp)$ of cross-linked rice starch were lower than native starch $(71.6^{\circ}C,\;3,976\;cp)$, but holding strength $(2,177{\sim}2,708\;cp)$ and final viscosity $(3,424{\sim}3,826 \;cp)$ of cross-linked rice starch were higher than native starch (1,000 cp, 2,312 cp). DSC thermal transitions of cross-linked rice starches were shifted to a lower temperature than native rice starch but there was no significant difference in gelatinization enthalpy between native and cross-linked rice starches. X-ray diffraction pattern of both native and cross-linked rice starches showed typical A-type crystal indicating that cross-linking had not affected the crystalline region of starch.

• Journal of Ginseng Research
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• v.8 no.2
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• pp.135-152
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• 1984

Solubility and degree of swelling of the starch were about 15% and 30%, respectively when the starch in agueous solution was heated at 90$^{\circ}C$ for 30minutes. The starch showed no singnificant differences in the degree of swelling and soblubility with a growing period of ginseng. The starch was begun gelatinize at 50-55$^{\circ}C$ and completed at 65-70$^{\circ}C$ by the amy tical methods of X-ray diffraction, disappearance of crystalinity. Brabender angly lographic analysis and amylase digestion test. The maximum and minimum peak viscosities of 10% starch solution were 5.500 B.U and 1960 B.U, respectively. The starch showed no significant differences in pasting temperature, maximum and minimum viscosities on amylogram with a growing period of ginseng. The intrinsic viscosities of the starch and amylose were 0.54 and 1.5-1.9, respectively.

• Food Engineering Progress
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• v.15 no.4
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• pp.332-337
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• 2011

Physicochemical properties of hydroxypropylated and cross-linked (HPCL) rice starch were investigated. Dual modification of rice starch was carried out by hydroxypropylation using propylene oxide (2, 6, and 12%) and then crosslinking using phosphorus oxychloride (0.005% and 0.02%). Swelling power of dual-modified rice starch increased at lower temperature (60$^{\circ}C$) than that of native rice starch (70$^{\circ}C$). HPCL rice starch showed slightly lower solubility (1.6-6.1%) than native rice starch (2.2-13.8%). Solubility and swelling power tended to gradually increase with increasing phosphorus oxychloride contents. RVA pasting temperature (66.2-70.8$^{\circ}C$) and peak viscosity (160.6- 171.1 RVU) of HPCL rice starch were lower than that of those of native starch (71.3$^{\circ}C$, 190.4 RVU) and decreased with increasing propylene oxide concentration. DSC thermal transitions of HPCL rice starches shifted to lower temperature and show less amylopectin melting enthalpy (11.8-9.8 J/g) than that of native rice starch (11.9 J/g). Overall, physicohemical properties of HPCL rice starches were highly dependent on hydroxypropylation rather than crosslinking.