• Korean Journal of Food Science and Technology
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• v.33 no.1
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• pp.60-65
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• 2001

Physicochemical properties of 4 kinds of domestic and 7 kinds of foreign starch vermicelli (1 from Chinese, 6 from Japan) were determined. Peak temperature of starch vermicelli measured by DSC were $42{\sim}48^{\circ}C$ which were much lower than gelatinization temperatures of their raw material starches. X-ray diffraction peaks of starch vermicelli were not sharp compared with those of raw material starches which indicated that starches were gelatinized by heating and retrograded by cooling and freezing during production of starch vermicelli. Hardness and compression slope of sweet potato starch vermicelli measured by rheometer were respectively $9,500{\sim}11,000\;g/cm^2$ and $18,000{\sim}26,000\;g/cm^2$ which were twice higher than those of corn starch vermicelli. Cooking loss of corn starch vermicelli, which was 19.8%, was higher than that of sweet potato starch vermicelli, $4.2{\sim}6.6%$ and mung bean starch vermicelli, 7.7%. In changes of thickness of starch vermicelli during cooking i.e swelling ratio, sweet potato starch vermicelli had $58{\sim}69%$ of swelling ratio, which was higher than that of corn starch vermicelli, 50%. Corn starch vermicelli, which was relatively less elastic and easily broken, was shown to be inferior to that of sweet potato starch vermicelli in overall quality.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.8
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• pp.1124-1130
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• 2014

The objective of this study was to determine the responses in the digestibility of dry matter (DM) and amino acid (AA) composition of ileal endogenous flow (IEF) of pigs (initial body weight, $69.1{\pm}6.46$ kg) fed N-free diets (NFD) formulated with different ratios of corn starch to dextrose. Fifteen pigs fitted with a T-cannula at the distal ileum were fed 5 diets according to a triplicated $5{\times}2$ incomplete Latin-square design. Each period consisted of a 5-d adjustment period and 2 d of ileal digesta collection for 12 h on each of d 6 and 7 and between each period, there was a 5-d recovery period to avoid abnormal weight loss. The ratios of corn starch to dextrose investigated were 0:879, 293:586, 586:293, 779:100, and 879:0 for diet numbers 1, 2, 3, 4 and 5, respectively, and chromic oxide (5 g/kg) was used as an indigestible index. Ileal DM digestibility was greater in Diet 1 than that in Diet 4 (89.5% vs 87.3%, p<0.01) but they were not different from Diet 2, 3, or 5. The IEF for most of indispensable AA were not different among diets with the exception of Met, in which a lack of corn starch or dextrose gave lower (p = 0.028) IEF of Met than diets containing corn starch and dextrose. Likewise, the dispensable AA and total AA in the IEF did not differ among diets. The respective IEF of AA (mg/kg of dry matter intake) in pigs fed Diets 1, 2, 3, 4, or 5 were 301, 434, 377, 477,or 365 for Lys, 61, 89, 71, 87, or 61 for Met, and 477, 590, 472, 520, or 436 for Thr. Proline was the most abundant AA in the IEF followed by Gly, Glu, and Asp and together accounted for approximately 50% of the total ileal AA flows of pigs fed NFD. In conclusion, the variation in proportion of corn starch and dextrose in a NFD does not largely affect estimates of IEF of N and AA for growing-finishing pigs.

• Korean Journal of Food Science and Technology
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• v.23 no.5
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• pp.642-645
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• 1991

The rheological properties of wheat flours and corn starch and cooking properties of dry noodle in the presence of calcium phosphate hydroxyapatite(Ca-P) were studied. The additive($0.2{\sim}0.8%$) had essentially no effects on farinograms of strong and all-purpose wheat flours, however, they decreased the amylograph pasting temperature and increased the peak viscosity of flours, which was more pronounced in all-purpose flour. The cooking properties of dry noodles in the presence or absence of the Ca-P showed no significant differences, but the cutting forces of cooked noodles were increased by Ca-P at 0.4%. The pasting properties of corn starch in the presence of Ca-P($0.2{\sim}0.8%$) were similar to those of wheat flour. The gelatinization temperature of corn starch by differential scanning calorimeter decreased by $1^{\circ}C$ in the presence of 0.4% Ca-P. The time constant, a reciprocal of rate constant, of corn starch gel was slightly increased in the presence of 0.2 or 0.4% Ca-P.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.38 no.5 s.118
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• pp.38-46
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• 2006

Many researches for extensive uses of Hanji have been performed. With the advent of an information-oriented age, the development of Hanji which is printable has been considered as a new field of study. Since Hanji has many drawbacks in comparison with common printing papers, that is, rougher surface, huger absorption of ink and lower physical properties and printabilities. Improving the properties and printabilities of Hanji is therefore the most important work to deal with. This study was conducted to find out useful mixed agents for surface sizing suitable for printable Hanji. Four surface sizing agents (CMC, corn starch, PYA, AKD) were applied for mixture in this study. The physical properties of surface sized Hanji were measured. Results obtained were as follows. Based on designated agents according to concentration, each of the mixed agents was prepared. The kinds of mixture were corn starch (3%) and PVA (5%), corn starch (3%) and AKD (0.1%), corn starch (3%) and CMC (1%), AKD (0.1%) and CMC (1%), AKD (0.1%) and PVA (5%), CMC (1%) and PVA (5%). Each mixed surface sizing agents was included with these ratios (100:0, 90:10, 70:30, 50:50, 30:70, 10:90, 0:100) respectively. All the mixed agents improved the physical properties and printabilities of Hanji. Among them, mixed agent of CMC (1%) and corn starch (3%) with 90:10 ratio is superior to the others for not only smoothness but also ink printability. In view of the result achieved, it is regarded that it can be fit for using Hanji as a printing paper and turned out to be a good contribution to Hanji industry.

• Applied Biological Chemistry
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• v.40 no.3
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• pp.220-224
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• 1997

As corn starches with different amylose content were heated at different temperature $(100^{\circ}C,\;121^{\circ}C)$ with starch / water ratio (1:3.5, 1:9) and heating-cooling treatment was repeated up to 4 times, the yield of RS(resistant starch) from heated corn starches was investigated by the enzymatic-gravimetric method and the ${\alpha}-amylase$ treatment. Compared to ${\alpha}-amylase$ method, enzymatic-gravimetric method was more effective to hydrolyze the amorphous region of heated corn starch. With increasing the amylose content and the number of heating-cooling treatment, the yield of RS increased, regardless of isolation method. Heated corn starches formed at $121^{\circ}C$ provided higher yield of RS than those formed at $100^{\circ}C$. Higher RS yield was also observed in the case of starch/water ratio (1:3.5) compared to the case of ratio (1:9).

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.1023-1029
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• 2002

Relationship between RVA properties and physical properties of film made from native corn starch and hydroxypropylated corn starch at various levels of plasticizers was examinel. Tensile strength of the film decreased, but its elongation and water vapor permeability increased with increasing plasticizer concentration. The film with glycerol showed greater changes in physical properties than that with sorbitol. Hydroxypropylated starch film showed lower tensile strength, higher elongation, and higher water vapor permeability than the native starch film. Sorbitol resulted in films with relatively high tensile strength, whereas glycerol produced films with increased elongation. The most reliable parameters for the relationship between RVA properties and film properties were RVA peak viscosity, tensile strength, and water vapor permeability. Water vapor permeability and tensile strength had linear relationship with RVA properties. The tensile strength and water vapor permeability of film could be predicted using the RVA peak viscosity.

• Applied Biological Chemistry
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• v.29 no.4
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• pp.333-338
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• 1986

Physicochemical properties of starch isolated from germinated corn were investigated and compared with those of nongerminated corn starch. Amylose content and initial gelatinization temperature of germinated starch were lower than those of nongerminated starch. Swelling power and solubility of both starches exhibited two stage behavior, however germinated starch revealed lower swelling power and higher solubility compared to those of nongerminated starch. Both starches showed a typical A type X-ray diffraction and irregular oval shape including partly polygon with the size of $10-25{\mu}m$. However, germinated starch showed many holes with the size of $1-2{\mu}m$ on the surface of granule.

• Microbiology and Biotechnology Letters
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• v.19 no.5
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• pp.514-520
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• 1991

Direct synthesis of cyclodextrin (CD) from extruded insoluble corn starch without liquefaction procedure using cyclodextrin glucanotransferase (CGTase) was carried out. Increased CD production rate and yield were achieved in heterogeneous enzyme reaction system containing extruded corn starch compared with those of conventional system employing liquefied or partially cyclized starch. At extruded starch concentration of 100 g/l the CD concentration and conversion yield were reached up to 54 g/l and 0.54, respectively. High purity of $\alpha \beta \gamma$-CDs without accumulation of undesirable malto-oligosaccharides was produced, furthermore, the residual extruded starch was easily separated by centrifugation from reaction mixture, whlch will facilitate the purification procedure. Granular structure of extruded starch was observed by SEM to investigate enzyme reaction mechanism. Supplemental addition of $\alpha$-amylase enhanced slightly the initial CD production rate, but it decomposed produced CD at the late stage. Various! extruded raw starches, such as, corn, rice, and barley were also suitable substrates for CD production.

• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1024-1028
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• 1998

Crystalline structure of the extrudate of high amylose corn starch was studied by X-ray diffractometer and $^{13}C\;NMR$. The X-ray diffraction crystal ratio of the extrudates (barrel temperature $100^{\circ}C$ )of high amylose corn starch slightly increased from 6.08% to 8.37% by increasing feed moisture content from 25% to 45%. But extrudates of high amylose corn starch showed similar crystal ratio on various extrusion conditions. Extrudates of high amylose corn starch (feed moisture content 20%, barrel temp $140^{\circ}C$) showed more enlarged crystal structure than that of non-extrudates. The perpendicular distance of crystal increased by extrusion. Crystal ratio was changed from $6.3{\sim}8.3%$ to $4.5{\sim}5.8%$ during storage at $4^{\circ}C$. Starch configuration was examined with $^{13}C\;NMR$. Double helical content was measured by $^{13}C\;NMR$ method. The highest double helical content (60%) was obtained from high amylose corn starch extrudate (barrel temp.: $100^{\circ}C$, feed moisture content 45%). Double helical contents and resistant starch (RS) yield (pancreatin) were positively correlated. However, double helical content of the extrudates was not changed by the storage at $4^{\circ}C$.

• Applied Biological Chemistry
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• v.27 no.3
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• pp.214-216
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• 1984

Alkali gelatinization of rice, corn, arrow root and ginger root starches at various sodium hydroxide concentrations was investigated. Critical concentrations of alkali for starch gelatinization ranged from 2.33 to 3.17 meq NaOH per gram of starch. Ginger root starch was most resistant to alkali gelatinization and arrow root starch was least stable to alkali.