• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.475-478
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• 1994

The hydrolyzability of chemically modified starches and ramen staches was determined by hog pancreatic ${\alpha}-amylase$ in vitro test. The extents of hydrolysis were 64.5% and 59.3% in native and acetylated potato starch, 70.5% and 60.4% in native and hydroxypropylated corn starch, and 65.2% and 57.3% in native and hydroxypropylated high amylose corn starch, respectively. The hydrolysis extents of waxy corn starch derivatives were shown in the descending order of pregelatinized (74.3%)>native (72.1%)>acetylated (66.5%)>acetyl distarch adiphate (56.4%)>hydroxypropyl distarch phosphate (50.7%). In the test on starches of container and regular ramen cooked by practical way, no significant difference was observed between ramen products of five different makers. Although the hydrolysis rate and extent of chemically modified starches were lower than those of native starches, the digestibility of ramen seemed to be not affected in the common diet as the use level of modified starch was relatively low.

• The Korean Journal of Food And Nutrition
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• v.32 no.4
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• pp.304-311
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• 2019

Ohmic heating is a heating method based on the principle when an electrical current passes through food. Since this method is internal, electrical current damage occurred during heating treatment. The results of ohmic heated starch's external structure, X-ray diffraction, DSC analysis and RVA were differed from those of conventional heating at the same temperature. Several starches changed more rigid by structure re-aggregation. This change in starch was caused by change of physical, chemical, rheological property. The rheology of ohmic heated potato and corn starch of different heated methods were compared with chemically modified starch. After gelatinization, sample starch suspension (2%, 3%) measured flow curves by rheometer. Cross-linked chemically modified starch's shear stress was decreased with degree of substitution reversibly. Ohmic heated more dramatic, at $60^{\circ}C$. Potato starch's shear stress was less than commercial high cross-linked modified starch. Flow curves of potato starches measured at $4^{\circ}C$, $10^{\circ}C$, $20^{\circ}C$. Showed that Ohmic heated potato starch's shear stress ranging between $4^{\circ}C$ and $20^{\circ}C$ was narrower than modified starch. According to this study, ohmic heated potato starch can be used by decreasing viscosity agent like cross-linked modified starch.

• Journal of the Korean Society of Food Culture
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• v.22 no.1
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• pp.91-96
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• 2007

Developing carbohydrate fat replacer as materials for low-calorie and low-fat food made of Korean potato, it is expected that the new demand of fat replacer will be created. Potato starch was modified by chemical modification. Observing modified starch(treated in different method) by SEM, EZ(treated by enzyme) showed shape of deformed round oval, AC(treated by acetylation,), HPR(treated by hydropropylation) showed shape similar to that of NL(N-Lite), the commercial fat replacer. In the modified starch such as AC, peak in B and C type similar to those of general starch was found, but EZ showed non-crystalline shape. Compared to other modified starch, HPR, the chemically produced denatured starch showed very peculiar peak and structure in V-form. While the order of contents of amylopectin was in the order HPR > EZ > AC showed extremely high contents. Measuring the degree of gelatinization per the modified method, the degree of gelatinization of HPR as much higher than others. The water binding activity of modified starch was 240% in HPR. Measuring viscosity by producing general starch and modified starch as gel of 10% concentration, the CPS showed very high viscosity of 30.30 ${\times}$ 10$^3$ cp. Showing viscosity of 38.60, 31.60 10$^3$ ${\times}$ cp, the modified starch was in the order of HPR. While the calorie of starch of GPS was measured to be 3.0 Kcal/g, very low calorie those of chemically modified starch, HPR showed 2.5 Kcal/g respectively, suggesting that calorie is decreased by modified treatment. The appropriateness of processing food was experimented by substituting the existing oil and fat containing food with saturated gel of starch and modified starch in constant rate through utilization of modified starch. Therefore, research and development for materials and related products which maintain the existing quality and reduce fat contents will be constantly performed in the future.

• Polymer(Korea)
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• v.35 no.6
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• pp.580-585
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• 2011

This article aims to enhance the biodegradability and environment-friendliness of petroleum based biodegradable poly(butylene adipate-co-succinate-co-terephthalate)(PBAST) by blending chemically modified thermoplastic starch(CMPS). CMPS is a kind of bio-based biodegradable resin which is manufactured by reacting starch with maleic anhydride(MA) in the presence of a plasticizer and a free radical initiator. The characteristic properties of PBAST/CMPS blends were investigated by observing their morphology, thermal, mechanical properties, and biodegradability. The good interfacial adhesion between the phases examined by SEM revealed that PBAST/CMPS blends were compatible blends. The tensile strength and elongation decreased with increasing CMPS content, while modulus increased. The biodegradability of the blends was much higher than that of pristine PBAST and increased with increasing CMPS contents.

• Journal of the Korean Society of Food Culture
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• v.22 no.2
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• pp.254-260
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• 2007

This study was examined closely physiological activation and intended to present the possibility of developing food low-fat food. Developing carbohydrate fat replacer as materials for low-fat food made of Korean potato starch, it is expected that the new demand of fat replacer will be created. Potato starch was modified by chemical modification. The calorie of starch of GPS was measured to be 3.0 kcal/g, those of chemically modified starch, HPR showed 2.5 kcal/g respectively, suggesting that calorie is decreased by modified treatment. The appropriateness of processing food was experimented by substituting the existing oil and fat containing food with gel of starch and modified starch in constant rate through utilization of modified starch. When producing mayonnaise by substituting edible oil with gel of modified starch in 10-50%, calorie was reduced by 44${\sim}$45% when substituted by 50%, suggesting the potential of low-fat food. Measuring viscosity of mayonnaise by Brookfield viscometer, the mayonnaise with HPR showed high viscosity and the chemical modified starch group of EZ also showed high viscosity. Generally, the material property of mayonnaise tended to reduce in all measured items when oil and fat are substituted by starch substituting materials and the substituting materials increase. When it comes to the emulsification stability of mayonnaise with starch substituting materials, emulsification stability of all mayonnaise with starch substituting materials is lower than that of compared group. While the group with NL as commercial fat replacer showed emulsification stability which was slightly higher than group with modified starch and the substitution group of HPR showed higher emulsification stability. Sensory evaluation for low-fat mayonnaise by substituting oil the products substituted by modified starch was more preferred than general starch substituting products such as GPS. While NL as commercially fat replacer showed the hight preference, products with H40, EZ were also highly preferred.

• Food Science and Biotechnology
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• v.16 no.4
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• pp.646-649
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• 2007

The effect of the addition of 2 kinds of chemically modified starches (the anti-caking agents; tapioca starch and com starch) on caking of ramen soup was observed using a low-resolution proton-pulsed nuclear magnetic resonance (NMR) technique. After storing ramen soup samples with diverse compositions of modified starch at 20-40% relative humidity for 4 weeks, changes in the spin-spin relaxation time constant ($T_2$) were measured as a function of temperature. $T_2-Temperature$ curves for ramen soup containing modified starches showed that the caking initiation temperature (glass transition temperature) was increased by $5^{\circ}C$ following the addition of only 0.5% modified cornstarch. The results indicate that the modified com starch used in this study would be an effective anti-caking agent for ramen soup, thus prolonging the shelf life of the product.

• Polymer(Korea)
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• v.33 no.2
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• pp.164-168
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• 2009

The effects of chemically modified thermoplastic starch (CMPS) on the morphology, thermal and mechanical properties of the blends of poly (lactic acid)(PLA) and poly(butylene adipate-co-terephthalate)(PBAT) were studied. Blends of PLA/PBAT with the CMPS contents of 10, 20 and 30 wt% on the basis of PLA/PBAT weight were prepared by a twin screw extruder. The morphology, thermal and mechanical properties of the blends were examined by using scanning electron microscope (SEM), differential scanning calorimeter (DSC) and a tensile tester. The DSC study revealed that PLA/PBAT blends are thermodynamically immiscible, while the compatibility was much improved by addition of the CMPS.

• Food Science and Preservation
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• v.13 no.3
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• pp.404-412
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• 2006

TThe purpose of this study was to investigate the physicochemical properties of chufa(Cyperus esculentus L., var sativus Boeck) starches by physical and chemical modification. Chufa starches were exposed to the microwave with 700W power oven for 1, 2, and 3 minutes. Also, starch was oxidized with 1.5%, 3% and 6% (15, 30, 60 mg Cl2/g starch $40^{\circ}\C$, pH 10, 3.0 hr) sodium hypochlorite. The shape of starch granules was not changed much by microwave heating and sodium hypochlorite. Water binding capacity increased but amylose content swelling power, and solubility decreased with increasing microwave heating time. Water binding capacity of the oxidized starch decreased with increasing the content of sodium hypochlorite. With increasing the microwave heating time, gelatinization temperature decreased, but enthalpy(${\Delta}H$) increased in physical modification of chufa starches. Also, chemically modified chufa starches have the similar pattern in gelatinization properties. Peak viscosities of RVA in physically modified chufa starches were 416-188 RVU, and in chemically modified chufa starches they were 129-267 RVU.

• Korean Journal of Food Science and Technology
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• v.40 no.3
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• pp.290-296
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• 2008

This study examined the physicochemical properties of chemically and enzymatically cross-modified waxy rice starches. The waxy rice starch was cross-linked using phosphorous oxychloride, and then partially hydrolyzed with four commercial ${\alpha}$-amylases (Fungamyl, Termamyl, Liquozyme, Kleistase). Swelling power and the moisture sorption isotherm did not change with cross-modification. Two cross-modified waxy rice starches (hydrolyzed with Termamyl and Liquozyme) showed higher solubilities than native starch and the two other cross-modified starches (hydrolyzed with Fungamyl and Kleistase). In terms of RVA characteristics, the two cross-modified waxy rice starches hydrolyzed with Termamyl and Liquozyme, respectively, had lower peak viscosity, holding strength, and final viscosity than the native starch. However, the two starches hydrolyzed with Fungamyl and Kleistase, respectively, revealed higher peak viscosity, holding strength, and final viscosity than the native starch. No differences were displayed in the X-ray diffraction patterns and DSC thermal characteristics of the cross-modified waxy rice starch as compared to both the native and cross-linked starches, indicating that cross-linking and enzymatic hydrolysis occurred in the amorphous region and did not alter the crystalline region.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.1
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• pp.39-46
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• 2004

Waxy maize starches are inherently stable in soluble status and can be chemically modified to improve stability along with heat, acid and shear resistance. This study was carried out to investigate the effect of theological and sensory characteristics of the yellow layer cake made by adding different levels of waxy maize starch as a fat substitute for shortening. By increasing the substitution level of waxy maize starch for shortening, the specific gravity of cake batter increased and the viscosity decreased. The microstructures of cake crumb observed by the scanning electron microscope were not different significantly, and the size of air cells and fat particles also were not substantially decreased by increasing fat substitution level. The texture profile analysis using texture analyzer decreased by increasing the different substituting levels of waxy maize starch. Among various sensory properties, the color value of layer cake increased by increasing the level of waxy maize starch. However, the appearance, flavor, taste, texture and overall preference decreased.