• Journal of the Korean Home Economics Association
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• v.39 no.1
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• pp.103-111
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• 2001

This study was attempted to investigate the effect of partial replacement of rice flour with black or brown rice flour on texture properties and retrogradation of Julpyun(Korean rice cake). In sensory evaluation, the Julpyuns replaced black or brown rice flour 20% had high score in color, flavor and overall acceptability not including mouthfeel. As the result of the measurement with texture analyzer, hardness, gumminess and chewiness of Julpyuns tended to decrease in proportion to the amount of black and brown rice flour in the formula. These resets implied that the degree of retrogradation of black and brown rice Julpyuns might be low. Julpyuns replaced with black rice were a little lower than those of brown rice in the hardness. In the retrogradation speed by Avrami,s equation, the rate constants of Julpyun replaced black and brown rice flour was lower than that of milled rice, restating in delay in firming.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.140-146
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• 2000

The physicochemical properties, such as retrogradation, fat acidity and viscosity, on the pine nut's gruel at various contents of pine nut (0, 1, 3 and 5%) during storage at 4, 25 and $40^{\circ}C$ were investigated. The degree of retrogradation was increased rapidly at the initial storage stage. The lowest value (about 10%) of the degree of retrogradation was observed in the gruel sample containing 3% of pine nut. Also, the rate constant of retrogradation was showed the lowest value (0.0422) in the gruel containing 3% of pine nut regardless of storage temperatures. The fat acidity was showed the lower value than 30 mg KOH in all samples. The viscosity increasing velocity(RVU/min) between holding strength and final viscosity was decreased as the pine nut's content was increased. However, it was not affected by the storage temperatures.

• Korean journal of food and cookery science
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• v.8 no.3
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• pp.281-289
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• 1992

The physicochemical, rheological and sensory characteristics of Backsulgies added with dietary fibers-cellulose, pectin and wheat bran-were investigated. The maximum acceptable ratio of fibers was 10% for wheat bran or cellulose, 3% for pectin. As me results of physicochemical analysis, cellulose and pectin had larger water-binding capacity man wheat bran. Swelling power was increased with temperature increment. But the type of added dietary fiber did not make significant differences. The degree of gelatinization was measured by maltose content. The retrogradation of backsulgies was significantly delayed by the addition of dietary fibers. The retardation effect of dietary fibers for retrogradation of backsulgies was also proved by textural analysis and time constant determination of Avrami equation. Pectin had especially excellent delaying effect while me storage time extended. There were no significant differences in sensory characteristics between me backsulgi with no dietary fibers and backsulgies added with cellulose 3%, pectin 1% and wheat bran 3%. Therefore, we concluded mat cellulose 3%, pectin 1% and wheat bran 3% were me optimum addition ratios, which have the delaying effect of retrogradation, and which could be accepted as same as conventional backsulgies organoreptically.

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

• Preventive Nutrition and Food Science
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• v.16 no.2
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• pp.157-164
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• 2011

The influence of sodium salts and chlorides at various concentrations (0.05, 0.10, 0.50, and 1.00%) on the reheating behavior of retrograded rice starch and cooked rice was investigated. The degree of gelatinization of the all retrograded rice starch gels and the cooked rice containing sodium salts and chlorides increased after reheating compared to the starches without salt. Gelatinization also showed an increasing trend as the concentration of sodium salts and chlorides increased. The increase of gelatinization after reheating the samples containing sodium salts and chlorides was greater than 38.0%. The reheated retrograded rice starch and cooked rice containing $Na_3PO_4$ showed the lowest set back value and retrogradation rate constant. Among all the samples, the cooked sample containing $Na_3PO_4$ showed the highest increment of gelatinization after reheating. Also, this same sample showed the lowest retrogradation degree.

• Korean journal of food and cookery science
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• v.9 no.2
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• pp.67-73
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• 1993

The effects of addition of brown rice flour on the Backsulgies were examined. We chose the addition ratio of brown rice flour as 0%, 50%, 100% along with the pilot study. The addition of brown rice flour did not make significant changes in water-binding capacity, swelling power and the degree of gelatinization. But the addition of brown rice flour had a delaying effect of retrogradation of Backsulgies by textural analysis. In sensory evaluation, the Backsulgi added brown rice flour 50% had the highest value in the overall quality of sensory characteristics. But there was no significant difference in the other sensory characteristics between the 50% and 0% added with. Therefore we concluded that the addition of brown rice flour on Backsulgies improve the sensory characteristics as well as delay the retrogradation and would be a good source of dietary fiber.

• Korean Journal of Food Science and Technology
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• v.28 no.2
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• pp.305-310
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• 1996

The degrees of retrogradation (DR) for 50% rice flour gels kept at $4^{\circ}C$ and $20^{\circ}C$ for the 6-day storage period at 0.5, 1.0 and 2.0% (w/w, on dry weight basis) levels of lipid additives (sucrose fatty acid ester, SE1670; soybean oil) were measured by ${\alpha}$-amylase-iodine method, differential scanning calorimetry (DSC) and X-ray diffractometry. The DRs were higher in rice flour gels stored at $4^{\circ}C$ than those stored at $20^{\circ}C$. The sucrose fatty acid ester and soybean oil reduced the retrogradation of rice flour gels, but the effect was higher in samples stored for 1 day. The DR decreased more effectively in the addition of SE1670 than that of soybean oil In case of SE1670, the change of enthalpy by DSC showed similar patterns with the degree of retrogradation by ${\alpha}$-amylase method; however, it was not the case for soybean oil. The intensity of peak at $2{\theta}=16.7^{\circ}$ in X-ray diffraction pattern was reduced with lipid additives but it was not clear.

• Journal of the Korean Society of Food Culture
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• v.26 no.4
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• pp.400-408
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• 2011

This study was performed to analyze the retarded degree of Garaetteok retrogradation added with different ratios 0-15% (w/w) of apple pomace dietary fiber powder (DFP). SEM (${\times}$500) showed that air cell size on the Garaetteok surface increased as DFP content increased, whereas control had a compact structure without air cells. The degrees of Garaetteok retrogradation after 3 days at 4 and 25$^{\circ}C$ by ${\alpha}$-amylase iodine method were 57.44 and 41.55% for control, respectively. On the other hand, those of 15% DFP Garaetteok were 28.38 and 15.05%, respectively. Enthalpy changes (${\Delta}$E) by DSC of control, 10 and 20% DFP Garaetteok after 3 days of storage at 4$^{\circ}C$ were 4.41, 4.17, and 3.80 J/g, respectively, whereas those at 25$^{\circ}C$ were 2.14, 1.04, and 0.72 J/g. Hardness of 15% DFP Garaetteok was around 48% compared to that of control after 3 days of storage at 25$^{\circ}C$. Increasing DFP content from 0 to 15% decreased L color value from 86.2 to 55.1, whereas a and b values increased from -1.9 to 8.9 and from 5.3 to 20.8, respectively. In a sensory intensity test, hardnesses of 15% DEP Garaetteok were significantly different at 1 and 0.1% compared to those of control after production and followed by storage for 3 days at 4$^{\circ}C$, respectively.

• Korean journal of food and cookery science
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• v.29 no.3
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• pp.267-274
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• 2013

Demand for a rice cake, a popular traditional food in Korea, is rising, but its industrial-scale production is extremely difficult due to its short shelf-life caused by starch retrogradation and microbial spoilage. By means of the sourdough fermentation technique, we attempt to develop rice cakes with a longer shelf-life. Heterofermentative lactic acid bacteria (Weissella koreensis HO20, Weissella kimchii HO22) isolated from kimchi were used to ferment wet-milled rice flour for their abilities to produce exopolysaccharides and to inhibit the microbial spoilage of rice cakes. After 24 hr of fermentation at $25^{\circ}C$, viable cell counts in rice dough increased from $10^6$ CFU/g to $10^8$ CFU/g and total titratable acidity increased from 0.05% to 0.20%, whereas pH decreased from 6.5 to 5.1. Fermented rice flour showed significantly lower peak, trough, and final viscosities as well as breakdown and setback viscosities measured by rapid viscoanalyzer. Both lactic acid bacteria showed in vitro antifungal activity against Penicillium crustosum isolated from rice cakes. The antifungal activity remained constant after the treatments with heat, proteinase K and trypsin, but fell significantly by increase of pH. Rice cakes made of fermented rice flour were found to retard mycelial growth of P. crustosum. The degree of retrogradation as measured by the hardness of the rice cake was significantly reduced by the use of fermented rice flour. The results suggest that use of fermented rice flour has a beneficial role in retarding starch retrogradation and in preventing fungal growth, hence extending the shelf-life of rice cakes.

• Korean Journal of Food Science and Technology
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• v.20 no.3
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• pp.331-337
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• 1988

The thermal properties of typical five Indica and five Japonica rice varieties were investigated by Differential Scanning Calorimetry (DSC). There was no significant difference in gelatinization temperature between Indica and Japonica varieties, but the average enthalpy of gelatinization was larger in Indica types than that in Japonica. However, the enthalpy of melting of amylose-lipid complex was larger in Japonica types than that in Indica types. The DSC thermogram of hydrolyzed rice residue included a smaller peak of gelatinization with narrow range of temperature. Retrogradation of gelatinized rice kernel was also determined with DSC theremograms. The endothermic peak areas clearly increased with increasing storage time at $4^{\circ}C$ so that the area could be used as a measure of the relative degree of retrogradation. The results indicated that Samgang variety(Indica) retrograded more rapidly than Chuncheong variety(Japonica).