• The Korean Journal of Food And Nutrition
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• v.19 no.3
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• pp.279-287
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• 2006

This study was carried out to investigate the influences of modified starches on suppression of retrogradation in Korean rice cake for their optimization, Garaeduk. Based upon studying Avrami equation, the Avrami exponent n value of all the experiment samples was found to be 1.03 ${\sim}$ 1.37 in the influence of modified starches on retrogradation of the rice cake. This means that the retrogradation of the Korean rice cake occurred instantly after the crystallization of starch particles in the Korean rice cake formulated by modified starches. The highest Avrami exponent n value was indicated in the control sample. The rate constant k of retrogradation in the Korean rice cake formulated by modified starches showed comparatively low and appeared to be the lowest in the Korean rice cake formulated by SHPP. This tendency was shown well in the time constant(1/k) of retrogradation velocity. According to the DSC analysis, the onset temperature of gelatinization in thermal characteristics showed somewhat high in case of addition of modified starch into the Korean rice cake on storage time and the SHPP was slowly gone up. In peak temperature of gelatinization in thermal characteristics of the DSC analysis, SSOS and ASA were increased a little in comparison with the control. The control was comparatively high increase. Melting enthalphy of all samples added with modified starches (SSOS: 21.1${\rightarrow}$23.7${\rightarrow}$24.1, ASA: 21.1${\rightarrow}$24.8${\rightarrow}$25.4) appeared to be lower than that of the Korean rice cake without modified starches(21.2${\rightarrow}$26.1${\rightarrow}$27.1). The Korean rice cake added with SHPP was shown to be the lowest in the increasing rate of melting enthalpy(20.9${\rightarrow}$21.4${\rightarrow}$22.1). Heat spreadability of all the samples in Martin melting diameter was revealed to be good in order of control, ASA, SSOS, SHPP and especially the Korean rice cake added with SHPP was shown to be the best in heat spreadability. In color, sensory examination and textural characteristic of the Korean rice cake added with modified starches, the L$^*$value was not changed practically with the storage time and seemed to be stable. The a$^*$ value of the samples was followed by control(2.21${\rightarrow}$5.34: 141.6%), ASA (2.01${\rightarrow}$4.22: 110.0%), SSOS (2.78${\rightarrow}$4.87: 75.2%) and SHPP (2.12${\rightarrow}$3.40: 60.4%) in order of color change. Also the b$^*$ value of the samples was followed by control(4.32${\rightarrow}$6.35: 47.0%), ASA (4.66${\rightarrow}$5.73: 23.0%), SSOS (4.90${\rightarrow}$5.89: 20.2%) and SHPP (4.89${\rightarrow}$5.12: 4.7%) and there was the least (or no) color change with the SHPP. Textural characteristics of samples was shown to be the highest in case of modified starch addition and especially SHPP appeared to be the best in texture.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.3
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• pp.386-392
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• 2015

The purpose of this study was to evaluate the quality characteristics and antioxidant activities of noodles added with Rehmanniae Radix Preparata powder (RP). Wheat flour noodles were prepared with four levels of RP (0, 2.5, 5, and 7.5%). Moisture absorption of RP added noodles was somewhat greater than that of control. The turbidity of RP noodles decreased according to addition of RP. Hunter L (lightness) and b (yellowness) values of RP added noodles decreased according to addition of RP amount. Textural properties (measured by a texture analyzer), hardness, and springiness of RP noodles up to 5% were not significantly different from those of control. Antioxidant activity of RP added noodles increased according to addition of RP: $IC_{50}$ values of DPPH radical scavenging activity for raw noodles was 3.77 mg/g, whereas values of raw noodles with RP 2.5 and 7.5% were 3.69 mg/g and 2.47 mg/g, respectively. Polyphenol content increased according to addition of RP. Amylogram showed that RP addition increased initial gelatinization temperature, decreased breakdown, and reduced setback and consistency, which indicates protection against retrogradation. The sensory preference test revealed that cooked noodles with added 2.5% RP showed the highest scores for color, odor, taste, and overall preference. It is suggested that RP up to 2.5% could be substituted for wheat flour to improve noodle quality.