• Journal of the East Asian Society of Dietary Life
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• v.3 no.2
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• pp.139-145
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• 1993

Retrogradation characteristics of the acetylated and raw starch were investigated with the chucheongbyeo and Samkangbyeo. The freeze-thaw stability and syneresis on starch gel were more stable and lower in acetylated rice starch, suggested that the rice starch acetylated with acetyl group is more stable in the various conditions. The retrogradation time constant of acetylated rice starch gel from the Chucheongbyeo and Samkangbyeo which were measured at 5$^{\circ}C$ storage were 11.7 days and 10.2 days, respectively. In addition, the retrogradation time constant in 21$^{\circ}C$ were 50.5 days and 49.8 days, indicating that retrogradation was noticiably retarded in this occation.

• Food Science and Biotechnology
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• v.17 no.4
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• pp.780-786
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• 2008

Effect of acetylated starches (acetylated rice starch and acetylated tapioca starch) on rheological properties of hot pepper-soybean paste (HPSP) at different mixing ratios of rice flour (RF) and acetylated starch (AS) (10/0, 9/1, 8/2, and 7/3) was evaluated in steady and dynamic shear. All HPSP samples at $25^{\circ}C$ exhibited shear-thinning (n=0.31-0.36) and thixotropic behavior with high yield stresses and their steady flow curves were well described by power law and Casson models. The presence of AS resulted in the decrease in consistency index (K), apparent viscosity (${\eta}_{a,100}$), and yield stress (${\sigma}_{oc}$), and their predominant decreases were noticed at higher ratio of RF to AS (7/3 ratio). Arrhenius temperature relationship represents variation with temperature in the range of $5-35^{\circ}C$ with the high determination coefficients ($R^2=0.97-0.99$). Dynamic moduli (G', G", and ${\eta}^*$) values of HPSP samples mixed with AS were lower than those of HPSP with no added AS within the experimental range of frequency (0.63-62.8 rad/sec). Steady and dynamic shear rheological properties of HPSP samples seem to be greatly influenced by the presence of acetylated starch.

• Food Science and Biotechnology
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• v.18 no.1
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• pp.118-123
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• 2009

In order to find out the effect of low level of starch acetylation on physicochemical properties of potato starch, amylose content, digestibility of raw and gelatinized starch, thermal properties, pasting properties, and the swelling power of native and acetylated potato starches were measured. The amylose content was significantly lower in acetylated starch than in their counterpart native starches. Though a tendency in the decrease in digestibility of raw starch was observed with starch acetylation, acetylation did not alter the proportion of readily digestible starch (RDS), slowly digestible starch (SDS), and resistant starch (RS) of both raw and gelatinized potato starches. No clear increase in the swelling power was observed, however, the peak and onset gelatinization temperatures and the enthalpy required for starch gelatinization decreased with starch acetylation. Peak and breakdown viscosities were reduced due to acetylation of potato starch while final viscosity and set back were increased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.8
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• pp.1264-1269
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• 2014

This study investigated the effects of rice starch addition, including native, acetylated, and hydroxypropy-lated rice starch, on the quality characteristics of instant fried noodles. Compared to 100% wheat flour (control), flours containing acetylated or hydroxypropylated rice starch showed reduced initial pasting temperatures as well as peak and breakdown viscosities as determined using a Rapid Visco-Analyzer (RVA). The addition of acetylated and hydroxylated rice starch as well as native rice starch increased cooked weight, volume, and water absorption of the fried noodles compared to control noodles. The addition of native rice starch tended to increase softness of noodles, whereas addition of acetylated or hydroxypropylated rice starch significantly lowered hardness, gumminess, and chewiness values. The results of the sensory evaluation indicate that noodles containing rice starch showed improved sensory characteristics such as color, appearance, flavor, taste, and texture. Especially, acetylated rice starch could be used to improve eating quality of instant fried noodles.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.817-821
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• 2007

The effect of acetylated rice (AR) starch at different concentrations (0, 4, 6, and 8%) on rheological properties of surimi sols and gels was studied. Dynamic frequency sweeps of surimi-AR starch sols at $10^{\circ}C$ showed that the magnitudes of storage moduli (G') decreased with an increase in starch concentration while those of tan ${\delta}$ increased, indicating that the effect of AR starch on the viscoelastic properties of surimi sols depended on starch concentration. In general, the G' thermograms of surimi sols showed the similar sol-gel transition pattern and they were also influenced by the addition of AR starch. The presence of AR starch in the surimi gel system reduced the gel strength and expressible moisture content (EMC). Surimi-AR starch gels showed better freeze-thaw stability compared to the control (0% starch concentration). The effect of AR starch on the rheological properties of surimi sols and gels appeared to be related to the swelling ability of starch granules in the presence of limited water available for starch.

• 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.

• Food Science and Biotechnology
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• v.17 no.5
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• pp.1119-1121
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• 2008

The effects of storage time (0, 1, and 2 month) and temperature (5, 15, and $25^{\circ}C$) on the dynamic rheological properties of hot pepper-soybean paste (HPSP) mixed with acetylated starches (AS) were studied by small-deformation oscillatory measurements. Dynamic moduli (G', G", and $\eta^*$) values of HPSP-AS mixtures increased with an increase in storage time and also decreased with increasing storage temperature. However, dynamic moduli values of the control (no added AS) were independent on storage time and temperature. Tan $\delta$ values (ratio of G"/G') in all HPSP samples did not change much with an increase in storage time and temperature. After 2 months of storage, the dynamic moduli of the HPSP-AS mixture samples were much lower than those of the control, indicating that the addition of AS can inhibit the retrogradation that developed over a long period of storage. Structural and rheological properties of HPSP samples seem to be stabilized by the presence of AS.

• The Korean Journal of Food And Nutrition
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• v.9 no.2
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• pp.107-115
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• 1996

In order to study the effect of modified starch and biopolymer on the quality of smoked pork sausage, acetylated starch and biopolymer were added to the smoked pork sausage and physical characteristics, sensory qualify, and water holding capacity were Investigated. In the textural characteristics SA, SB and SC group were lower in hardness than control group. Cohesiveness was lower only on the SA group which was added by 0.6% acetylated starch. Adhesiveness was higher on the SA and SC group by addition of biopolymer. All treatment group were lower in springiness than control group. The effect of biopolymer and acetylated starch on gumminess and chewiness was evident but not constant In each group. In the mechanical characteristics such as hardness, springiness, gumminess, chewiness were indicated positive correlation coefficient, the other hand negative correlation in adhesiveness. The result of folding test was not changed in 20 days storage. At 30 days storage SB group contained the 0.6% acetylate starch showed the best point. The other hand the biopolymer added SA and SC group less acceptable, the biopolymer added SA and SC group, which were added by biopolymer and acetylated, indicated cap. 65% lower VBN value than control group. Sensory evaluation were not significantly difference in hardness, fracturability and adhesiveness but cohesiveness was higher in SC group. Gumminess was significantly higher in SA and SC group by biopolymer addition. Overall acceptability in sensory evaluation were significantly higher In SC group by biopolymer addition. Overall acceptability in sensory evaluation correlated significantly with fracturability, chewiness and gumminess. Chewiness of sensory evaluation and mechanical gumminess were not significantly correlated.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.4
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• pp.487-492
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• 2006

Acetylated rice starches were prepared by reaction of rice starch with acetic anhydride, and their physicochemical properties as a function of degree of substitution (DS) were evaluated. The percentage of acetyl group and DS were $0{\sim}2.71%\;and\;0{\sim}0.104$, respectively. DS increased with increase in acetic anhydride content. DS increased swelling power and solubility of rice starch. Light transmittance (%) values of acetylated rice starches were much higher than that of native rice starch and increased with increase in DS. Rapid Visco Analyzer initial pasting temperature of acetylated rice starches decreased with increase in DS, while peak viscosity and breakdown values increased. Starch gets showed a significant decrease in syneresis (%) with the increase in DS.

• 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 $70^{\circ}C$.