• The Korean Journal of Food And Nutrition
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• v.30 no.4
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• pp.689-695
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• 2017

Ohmic heating is an internal heating method based on the principle that when an electrical current passes through food, electric resistance heat is uniformly generated internally by food resistance. Previous studies indicate that the thermal properties, external structure, internal structure, and swelling power of ohmic heat treated starch of various starches, such as potato, wheat, corn, and sweet potato, differed from those of conventional heating at the same temperature. In this study, the pasting property of starch, treated with ohmic and conventional heating, were measured by RVA (Rapid Visco-Analyzer). Our results show that as the ohmic heating temperature increased, the PV (Paste Viscosity) of the starch decreased significantly, and the PT (Pasting Temperature) increased. Changes in PV and PT indicate that the swelling of starch remains unchanged by ohm heating. The HPV (Hot Paste Viscosity), CPV (Cold Paste Viscosity) and SV (Setback Viscosity) of ohmic heated starch also differed from the conventional heated starch. The pasting property is similar to the viscosity curve of common cross-linked modified starch. In this experiment, we further confirm the similarity with modified starch and its usability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.4
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• pp.594-600
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• 1995

To efficiently utilize not only fresh chestnut(FC) but also wormy chestnut(WC), four types of chestnut starches which were fresh chestnut starch(FCS), fresh chestnut crude starch(FCCS), wormy crude starch(WCS) and wormy chestnut crude starch(WCCS) were extracted. Amylose content of FCS(46.5%) and water binding capacity of FCCS(103.0%) were higher than those of othe three, respectively. Swelling powers of all sample starches increased rapidly from 6$0^{\circ}C$ to 8$0^{\circ}C$. Solubilities showed the same pattern as the swelling powers. In the textural properteis investigated with IUTM(instron universal testing machine), hardnesses and elasticties of chestnut starches were 50~58I.U. and 14~16I.U., respectively. The results of textural evaluations showed that it was possible to prepare chestnut mook with FCS, FCCS and WCS.

• 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.

• 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.

• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.580-586
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• 1996

Gelatinization behavior and morphology of epichlorohydrin-crosslinked potato starches (XPs) were investigated. Native potato starch showed a very steep single stage swlling pattern, but crosslinked starches showed various patterns with the degree of crosslinking. Swelling power, solubility and light transmittance were reduced drastically as the degree of crosslinking increased. Brabender initial pasting temperature and peak temperature of crosslinked starches increased because the crosslinking reinforces the intermolecular net work of the starches. Although the swelling of the potato starch granule was inhibited by crosslinking as compared to that of the native one, Brabender peak viscosities (6.5% w/v, db) were on the order of 2,500 units for the native potato starch, 3,700 for the XP with 2.300 anhydroglucose units per crosslinking (AGU/CL) and 3,400 for the XP with 2,100 AGU/CL, due to the decreased breakdown of the swollen granule resulting from the resistance to heat and shear. The XP with 1,900 AGU/CL, however, did not show the peak viscosity and the viscosity was on the order of 500 units because of the excessive unhibition of the swelling. Unlike the native potato starch, 6.5%(m/v, db) pastes of the crosslinked potato starches could form gels, which could be predicted from the Brabender setback and consistency index. When the degree of crosslinking is low, random contraction and radial swelling of the granule was possible. As the degree of crosslinking increased, morphological change became similar to the single dimensional tangential swelling observed from the lenticular wheat starch. These morphological change during heating in excess water explained the gelatinization behaviors of crosslinked starches tested.

• Korean Journal of Food Science and Technology
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• v.25 no.4
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• pp.334-339
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• 1993

Physicochemical properties such as amylose content, swelling power, gelatinization and DSC of legume starches were investigated. The granule shape of legume starches was oval. The size of cowpea and mung bean were smaller than kidney bean and red bean. The amylose content of mung bean and kidney bean was larger and were $25{\sim}29%$. Swelling power of kidney bean starch was much lower than other starches in all temperature range. In gelatinization temperature by Brabender amylogram, red bean starch was low, but kidney bean starch was rather high. Amylographic hot-paste viscosity and set back of cow pea, mung bean and red bean starches were high. But those of kidney bean starch were very low. DSC results Indicated kidney bean starch gelatinized in higher temperature. From above results, row pea and mung bean starches were similar in granule size and shape, solubility and swelling power, amylogram, and DSC thermogram. But kidney bean starch was very different and red bean starch was slightly different with the physicochemical properties of cow pea and mung bean starches.

• 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.

• Archives of Pharmacal Research
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• v.29 no.12
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• pp.1179-1186
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• 2006

Cross-linked starch microspheres were prepared using different kinds of cross-linking agents. The influence of several parameters on morphology, size, swelling ratio and drug release rate from these microspheres were evaluated. These parameters included cross-linker type, concentration and the duration of cross-linking reaction. Microspheres cross-linked with glutaraldehyde had smooth surface compared with those prepared with epichlorhydrine or formaldehyde. The particle size increased with increasing the cross-linking time and increasing the drug loading. Swelling ratio of the particles was a function of cross-linker type but not the concentration or time of cross-linking. Drug release from starch microspheres was measured in phosphate buffer and also in phosphate buffer containing a-amylase. Results showed that microspheres cross-linked with epichlorhydrine released all their drug content in the first 30 minutes. However, cross-linking of the starch microspheres with glutaraldehyde or formaldehyde decreased drug release rate. SEM and drug release studies showed that cross-linked starch microspheres were susceptible to the enzymatic degradation under the influence of alpha-amylase. Changing the enzyme concentration from 5000 to 10,000 IU/L, increased drug release rate but higher concentration of enzyme (20,000 IU/L) caused no more acceleration.

• Korean Journal of Food Science and Technology
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• v.18 no.6
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• pp.437-442
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• 1986

Physicochemical properties of chestnut starch, which was adjusted at 14, 18, 21 and 24% moisture and heated for 16 hr at $100^{\circ}C$, were investigated. The cystallinity, swelling power and solubility of the starch were decreased upon heat-moisture treatments. The swelling power of the heat-moisture treated starch showed an inverse relation with moisture levels, while the solubility showed opposite trend. The swelling power and the solubility of both raw and heat-moisture treated starches held a liner relationship. The. water binding capacity of the starch was drastically increased upon heat-moisture treatments. Amylograms revealed that the heat-moisture treated starches had higher initial pasting temperature and lower viscosity than untreated starch. No peak viscosity was observed for the heat treated starches above 21% moisture. The minimum moisture contents for gelatinization of raw and heat-moisture (18%) treated starches were 45 and 40%, respectively. The gelatinization temperature of raw and heat-moisture (18%) treated starches was $65^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.34 no.3
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• pp.431-436
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• 2002

To develop a method for increasing RS level in maize starch, cross-linked resistant starches treated with annealing were prepared. Maize starch and amylomaize VII were used in the study and annealed at $40{\sim}60^{\circ}C$ before cross-linking modification. To compare effect of annealing below gelatinization temperature, starches were heat treated at 70 and $100^{\circ}C$. RS contents were assayed by pancreatin-gravimetric (P/G) method. When maize starch and amylomaize VII were cross-linked at $45^{\circ}C$ and pH 11.0 by slurrying the starch on a solution of STMP(sodium trimetaphosphate), STPP(sodium tripolyphosphate), and sodium sulfate, RS content was 14.7% and 45.3%, respectively. Annealing below gelatinization temperature before cross-linking increased RS contents of prepared cross-linked starches but did not affect the swelling power. Heat treatment above gelatinization temperature increased the swelling power of cross-linked starch prepared from maize starch. The characteristics by X-ray diffractometry and scanning electron microscopy of cross-linked resistant starch were not changed by annealing.