• Journal of the Korean Society of Food Science and Nutrition
• /
• v.32 no.8
• /
• pp.1253-1261
• /
• 2003

This study was carried out to investigate the influences of hydrocolloids on suppression of retrogradation in the Korean rice cake. Hydrocolloids were influenced to the textural characteristics of the Korean rice cake. In particular arabic gum and carrageenan had the effect of suppressing the retrogradation. Cohesiveness of the Korean rice cake added with hydrocolloids was shown to be high compared to control in organoleptic characteristics. Hydrocolloids exhibited slightly effective in retarding surface color change of the Korean rice cake. Onset temperature of gelatinization in thermal characteristics showed somewhat low in case of addition of arabic gum into the Korean rice cake and was followed by carrageenan, guar gum, gelatin and locust bean gum in onset temperature of gelatinization order. All samples added with hydrocolloids had low values in change of melting enthalphy and their range was 12.8 ∼ 17.7 J/g. The Korean rice cake added with arabic gum was lowest in melting enthalphy. The recrystallinity of the Korean rice cake added with arabic gum was greatly low compared to rice cake without hydrocolloids. Melting spreadability of the Korean rice cake added with arabic gum or carrageenan was superior in thermal characteristics. The value of exponent of Avrami was 0.97 ∼ 1.12 in study of Avrami equation. In conclusion carrageenan and arabic gum would have a suppressive effect of retrogradation in the Korean rice cake.

• The Korean Journal of Food And Nutrition
• /
• v.20 no.2
• /
• pp.185-194
• /
• 2007

This study was performed to evaluate the physicochemical, sensory evaluation of Backsulgi changed with germinated brown rice flour(GBRF) at different ratio. Moisture content decreased gently during storage and the decrease was less in GBRF-added groups than the control group. The color L value decreased significantly by with increasing the GBRF, wherease the redness(a) and yellowness(b) were both increased. As the result of measurement with texture analyzer, hardness, gumminess, chewiness, adhesiveness and fracturability of Backsulgi tended to decrease in proportion to the amount of GBRF in the formula. The thermal properties of Backsulgi were investigated by differential scanning calorimetry(DSC). Onset temperature and peak temperature of gelatinizatino in thermal characteristics showed low in case of addition of GBRF into Backsulgi. All samples changed with GBRF had low values in change of melting enthalphy. In the sensory evaluation, Backsulgi with GBRF were superior in flavor, cohesiveness, hardness, chewiness and moistureness than that of control. And Backsulgi with 20% GBRF showed the highest score in overall acceptability. Therefore we concluded that the addition of GBRF on Backsulgi improve the sensory characteristics as well as delay the retrogradation.

• Applied Biological Chemistry
• /
• v.37 no.6
• /
• pp.463-471
• /
• 1994

Physicochemical properties, gelatinization and retrogradation characteristics of surfactant added sweet potato starches were investigated. Three different surfactants, SSL (sodium stearoyl-2-lactylate), Dimodan (mono/diglyceride) and SE1670 (sucrose fatty acid ester 1670) were used. Shapes and crystallinities of starch granules were not changed by the addition of surfactants. Total lipid contents increased and the amylose content decreased by the addition of surfactants and the order was as follows: SE1670>SSL>Dimodan. The swelling power and solubility at $80^{\circ}C$ decreased in the surfactant added starches. By amylograph, initial gelatinization temperature of untreated sweet potato starch was $72.5^{\circ}C$, and did not change by the addition of surfactants, but SE1670 or Dimodan added starch showed the peak viscosity. The peak temperature of gelatinization and enthalpy of untreated starch by DSC were $53.9^{\circ}C$ and 1.3cal/g, respectively. The peak temperature increased by the addition of surfactants, while the enthalpy decreased. In gelatinization by alkali, the viscosity was lower in surfactant added starches than in untreated starch at concentration. The degree of retrogradation by ${\alpha}-amylase-iodine$ method was a lower in SSL and SE1670 added starches than untreated starch and the enthalpy by DSC also decreased in surfactant added and retrograded starches.

• Korean journal of food and cookery science
• /
• v.13 no.3
• /
• pp.278-285
• /
• 1997

The effects of three surfactants (SSL, Dimodan, and SE1670) on the properties of cooked nonwaxy and waxy rice during storage were investigated by sensory evaluation, instrumental test, and measurement of retrogradation degree. The results of sensory evaluation revealed that the overall quality of cooked rice was affected by textural characteristics. The addition of surfactant decreased the roughness and hardness of cooked rice, however, increased the stickiness and moistness during the storage in the order of SE, SSL, and Dimodan. In instron test, the hardness of surfactant-added cooked rice was significant lower than that of control. The addition of surfactant decreased the degree of retrogradation both in cooked nonwaxy and waxy rices.

• Korean journal of food and cookery science
• /
• v.18 no.4
• /
• pp.390-398
• /
• 2002

The purpose of this study was to select a cake ingredient acting as an emulsifier to retard the retrogradation of rice cake commercially available. For the purpose, Backsulgi, a traditional Korean rice cake, was prepared by adding various ingredients having high contents of lecithin such as raw soybean powder, parched soybean powder, soybean oil, egg yolk powder, and then the changes in the sensory and textural characteristics of the cakes were determined while storing them at the temperatures of 4$\^{C}$ and 20$\^{C}$ for 0, 1, 2 and 3 days. Based on the sensory evaluation, Backsulgi samples added with raw soybean flour were significantly different in roasted nutty smell, roasted nutty taste, softness, moistness, cohesiveness and overall quality compared with the control in the longer storage time at 20$\^{C}$.

• Korean Journal of Food Science and Technology
• /
• v.45 no.4
• /
• pp.460-465
• /
• 2013

Garaedduk made with various levels of buckwheat flour (0, 15, 30, and 45%) for rice flour was prepared using retrogradation-retardation technology and their physical and sensory properties were investigated. The moisture content of garaedduk decreased and the color differences increased as the ratio of buckwheat flour to rice flour increased. During storage at $4^{\circ}C$, the hardness values of garaedduk made with 15 and 30% buckwheat flour were maintained for up to three days. Immediately after manufacture, garaedduk made with higher levels of buckwheat flour had reduced overall acceptability. However, there was no significant difference in the overall acceptability of garaedduk made with 0 and 15% of buckwheat flour after storage. Therefore, buckwheat flour can replace rice flour with retrogradation-retardation technology to inhibit the starch retrogradation of garaedduk, which maintained its overall quality at a buckwheat flour level of 15%.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.36 no.10
• /
• pp.1320-1325
• /
• 2007

Retarding retrogradation of a Korean rice cake (Karedduk) added with carbohydrate materials after $0{\sim}30hrs$ of storage at $5^{\circ}C$ were investigated by Avrami equation using textural characteristics. Carbohydrate materials such as powdered sugar, trehalose, fructooligosaccharide (95%), isomalto, healtholigo, and galactooligo-saccharide (50%) were added in 0, 1, 5 or 10% levels on dry rice flour. In the amylogram, the breakdown (P-H) and consistency (C-H) for Karedduk added with carbohydrate materials were lower than those of the control. Decrease in the Avrami exponent (n) and increase in the time constant (1/k) of Karedduuk added with carbohydrate materials during storage determined by Avrami equation were important comparison factors to the control in terms of retrogradation rate analysis. The Aurami exponent (n) for control, fructooligosaccharide (95%) 10% and healtholigo 1% addition were 2.415, 1.977 and 3.297, respectively. The time constant (1/k) for fructooligosaccharide (95%) 5% and healtholigo 1% addition were lower than thecontrol. Lastly, Karedduk added with carbohydrate materials, except for fructooligosaccharide (95%) 5% and healtholigo 1% addition, was effective in retarding retrogradation.

• Korean journal of food and cookery science
• /
• v.19 no.2
• /
• pp.136-143
• /
• 2003

This study was carried out to investigate the quality of bread made with different types of brown rice flours. 20% of the wheat flour from the bread recipe was substituted with the different types of brown rice flours, such as, raw brown rice flour (RBRF), soaked brown rice flour (SOBRF), and sprouted brown rice flour (SPBRF). The loaf volume of the bread: decreased by 3.2%∼7.4% with the addition of the brown rice flours. The "L" value of these breads decreased, while the "a" and "b" values increased. In terms of the texture, the SPBRF bread was the hardest on the 1st day of storage, but it was the least hard on the 5th day of storage. The RBRF bread was the least springy. The SPBRF bread was the most cohesive. The adhesiveness was not significantly different among the breads. In terms of the degree of retrogradation using the ${\alpha}$-amylase method, the SOBRF and SPBRF breads showed a little lesser degree of retrogradation than the control and the RBRF bread. In the sensory evaluation, the control bread obtained high score for crumb color and grain, while the brown rice flours breads obtained high scores for mouthfeel and taste. Overall acceptability, defined by a higher score, was higher for the SOBRF and SPBRF breads than the control bread, which was not significant. Thus, this study showed that processing rice flour was more effective than raw rice flour in substituting wheat flour.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.44 no.10
• /
• pp.1517-1524
• /
• 2015

The purpose of this study was to determine the storage characteristics of Sulgidduk, a kind of rice cake, added with Portulaca oleracea L. The effect of P. oleracea L. paste (0, 1, 3, or 5%) on the storage qualities of Sulgidduk was evaluated during storage period at $20{\pm}2^{\circ}C$ for 3 days. As the amount of P. oleracea L. paste increased, loss of water in P. oleracea L. Sulgidduk decreased. Textural properties by texture profile analysis showed that hardness of Sulgidduk added with 5% P. oleracea L. paste was the lowest among treated samples. However, the hardness of all Sulgidduks increased during storage, regardless of the addition amount of P. oleracea L. paste. In accordance with the texture results, differential scanning calorimetry exhibited that the enthalpy of Sulgidduk with 5% P. oleracea L. addition was the lowest, indicating the delaying effect of P. oleracea L. paste on retrogradation of rice cake. From these results, the addition of P. oleracea L. to Sulgidduk extended shelf-life by delaying retrogradation.

• Korean journal of food and cookery science
• /
• v.17 no.4
• /
• pp.391-398
• /
• 2001

This study was carried out to investigate the effects of storage temperature(5$\^{C}$ and 25$\^{C}$) and time(1, 24, 48 and 72hours) on the retrogradation characteristics of mungbean starch gels by using differential scanning calorimeter, rapid visco-analyzer, $\beta$-amylase method, X-ray diffractometer and scanning electron microscope. Endothermic peaks of gels stored at 5$\^{C}$ were shifted to the lower temperature than those stored at 25$\^{C}$ and endothermic enthalpy of gels stored at 5$\^{C}$ was greater than that stored at 25$\^{C}$. DSC thermograms showed that the retrogradation rate of gels stored at 5$\^{C}$ was higher than that shored at 25$\^{C}$. The pasting properties of the gels such as peak viscosity and final viscosity increased with increasing storage time except the gels stored at 25$\^{C}$ for 72 hours and this trend was more apparent at the storage temperature of 5$\^{C}$. The digestibility measured by $\beta$-amylase method decreased with increasing storage time and this trend was more apparent at the storage temperature of 5$\^{C}$. X-ray diffraction patterns of the gels stored at 5$\^{C}$ showed more distinct peak than those stored at 25$\^{C}$, but no difference was detected by the storage time. The microstucture of all the gels showed a well developed three dimensional network The network structure of the gels stored at 25$\^{C}$ formed a thick matrix after 72 hours and those stored at 5$\^{C}$ from the early stage of storage.