• Journal of the East Asian Society of Dietary Life
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• v.17 no.6
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• pp.903-910
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• 2007

In order to make acquire a potential use for Opuntia humifusa as a natural functional food material, this study was performed to determine the quality properties of Jeung-pyun made with added Opuntia humifusa, or prickly pear powder. According to an analysis of its major components, we found that the prickly pear powder consisteds of nitrogen-free extracts (71.85%) and crude fiber (11.20%). Greater additions of prickly pear powder had resulted in significantly lower pH in the of Jeung-pyun. According to measurements on the degree of Jeung-pyun gelatinization, by means of ${\beta}$-amylase, greater additions of prickly pear powder led to the higher levels of isolated maltose, indicating that the gelatinization degree of the Jeung-pyun became higher. Also, samples with higher concentrations of prickly pear powder had a tendency toward lower water content, which allowed us to expect a longer storage duration for the Jeung-pyun. In the textural property tests the Jeung-pyun that had less hardness and greater adhesiveness (p<0.05) than the control group as the content of prickly pear powder became higher. Also, the Jeung-pyunhad lower gumminess and chewiness than the control group as the content of prickly pear powder became higher. Therefore, it is possible to prepare relatively soft Jeung-pyun using prickly pear powder. For the color differences of the Jeung-pyun samples, lower L- values, and higher a- and b -values (p<0.05) presented as the addition level of prickly pear powder became higher. According to SEM observations of the Jeung-pyun, the added prickly pear powder addition groups generally showed a smaller and more inconsistent pore size, but higher porosity, than the control group. According to sensory analyses of the Jeung-pyun, the P2 group scored highest for color item, and the P4 group generated the fermented scent. Higher additions content of prickly pear powder led to the lower score, but higher scores for adhesiveness. Finally, the P2 group achieved the highest score for overall taste.

• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.939-946
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• 1997

Effects of moisture content on the gelatinization and recrystallization of non-waxy and waxy rice starch gels were investigated by differential scanning calorimetry (DSC). The recrystallization rates of the starch gels containing various moisture contents $(40{\sim}70%)$ were analyzed by Avrami equation. The waxy rice starch had higher gelatinization temperature and enthalpy than non-waxy one. The highest degrees of recrystallization in both rice starch gels stored at $4^{\circ}C$ were shown at 40%, and recrystallizations above 80% moisture content were not found. The degree of recrystallization of waxy one was higher than that of non-waxy one in the range of 40 to 60% moisture content. The Avrami exponents (n) of both rice starch gels were near to 1.0 and the time constant (1/k) was increased with increasing moisture content in the range of 40 to 70% moisture content. The recrystallization rate of waxy rice starch gel was slower than that of non-waxy one. The recrystallization of rice starch gels could be explained by the change of ice melting enthalpy during storage. The Wg's, represented the maximum practical amount of plasticizing water, were about 29.9% and 28.2% for non-waxy and waxy rice starch gels, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.5
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• pp.525-533
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• 1992

To improve the food quality of traditional Jeung-pyun(Korean fermenfed rice cake), effect of mixed ingredients on the quality of protein enriched product was studied. Changes were evaluated in chemical and textural properties of protein enriched Jeung-pyun altered by fermentation time, temperature, and steaming time. The maximum volume wxpansion was noted in dough mixed with rice flour(100 g), soy flour(25 g), sucrose(20 g), Tak-ju(50 ml) and water(10 ml), and then fermented at $35^{\circ}C$ for 3 hours. Soy protein isolate(SPI) enriched rice dough had a maximum expanded volume when 15g(w/w) of SPI, 20g(w/w) of sucrose, 60ml(v/w) of Tak-ju and 50ml(v/w) of water added into 100g rice flour, and then fermented at $30^{\circ}C$ for 2 hours. Steaming after fermentation made the smaller volume of bulk $45^{\circ}C$-50% of the initial volume be showed just after fermentation. Protein enriched Jeung-pyun prepared under the maximal volume endowing conditions showed the best protein quality(protein digestibility and protein efficiency ratio) and starch structure which was susceptible towards enzyme reaction. The improved starch quality of protein enriched Jeung-pyun could be confirmed by reducing power, gelatinization degree and amylose content. Jeung-pyun riched with soy flour at 20% level or with SPI at 5% showed the best overall quality by sensory and textural property but it had a problem in browning.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.1
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• pp.101-108
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• 1992

Changes were evaluated in chemical and textural properties of Jeung-pyun (fermented rice cake) altered by the particle size of rice flour, amount of added Tak-ju (Korean traditional unrefined liquor) and sucrose, fermentation time and temperature, and steaming time. Particle size of polished rice flour did not affect the volume expansion during fermentation of rice dough by Tak-ju. The maximum expanded volume was noted in the dough, containing 20% sucrose (rice flour vs sucrose = 5 : 1, w/w), fermented at $35^{\circ}C$ for 3 hours. Any volume expansion was not occurred in rice dough without sucrose. The highest value of reducing power and gelatinization degree were observed in the rice dough with Tak-ju (rice flour vs Tak-ju = 2 : 1, w/v), while the lowest blue value was revealed in that case. Steaming followed after fermentation made the smaller volume of bulk by $45{\sim}50%$ of the initial volume be showed just after fermentation. Jeung-pyun prepared under the conditions could give maximum expanded volume by fermentation showed the best overall quality by sensory and textual properties.

• Journal of the Korean Society of Food Culture
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• v.10 no.2
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• pp.101-106
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• 1995

The effects of ${\alpha}-rice$ flour on the physicochemical properties of Korean rice cake were investigated. Before cooking, the degree of gelatinization of rice cake without ${\alpha}-rice$ flour was 5.75%, but 16% for adding ${\alpha}-rice$ flour. After cooking, the degree of gelatinization of rice cake were increased from 52% to 85% by adding ${\alpha}-rice$ flour. The L value of rice cake with ${\alpha}-rice$ flour increased, but there was no significant difference in L value between samples. The hardness of rice cake before and after cooking were increased by adding ${\alpha}-rice$ flour whereas after frozen stoarge there was no apparent effect on the color values of rice cake. The water absorption ratio of rice cakes during cooking were increased by addition of ${\alpha}-rice$ flour. Scanning electron photomicrographs revealed that the rice cake with ${\alpha}-rice$ flour has more porous structure with rapid rehydration.

• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.930-936
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• 2004

Effects of rice cultivars and degree of milling (DM) on composition, pasting properties, total phenolic contents, and distribution of phenolic acids were investigated. Rice and bran fractions with 94.4, 92.0, and 90.4% milling yields from brown rice of four cultivars (Odae, Nampyung, Chucheong, and Ilmi) were used. Fat and ash contents of milled rices decreased with increasing DM, whereas protein contents were not affected. In rice bran, differences in fat and ash contents by cultivars were higher than those caused by DM. With increasing DM, gelatinization temperature of rice flour decreased, whereas peak viscosity and hold viscosity at $95^{\circ}C$ increased. While cold viscosity, final viscosity, and setback varied among cultivars, DM had little effect. Total polyphenolic contents in brown rice, milled rice, and rice bran were 93.9-88.8, 30.3-71.9, and 310.0-541.6 mg catechin eq/100g, respectively. Major phenolic compounds were identified as ferulic and p-coumaric acids. Total phenolic content of brown rice (65.9-27.9 mg%) decreased with increasing DM, whereas ratio of ferulic acid composition increased. Chucheong and Ilmi varieties showed biggest reduction of phenolic acid contents by milling. In rice bran, ferulic and p-coumaric acids were 157.8-240.2 and 31.8-90.4 mg%, respectively. Contents of sinapinic, benzoic, and m-hydroxybenzoic acids in rice bran were higher than those of brown and milled rices.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.11
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• pp.1716-1723
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• 2014

This study was designed to examine the change in physical properties of extruded brown rice-vegetable mix at different pregelatinized brown rice contents and $CO_2$ gas injection. Moisture content, screw speed and die temperature were fixed to 30%, 100 rpm and 60, respectively. $CO_2$ gas injection was adjusted to 0, 300, 600, and 800 mL/min. The content of vegetables (carrot, pumpkin, kale and Angelica keiskei) mix was fixed 5%. Pregelatinized and raw brown rice powder were blended as the ratio of 0/95, 30/65 and 50/45. Specific mechanical energy input decreased as pregelatinized brown rice ratio increased. Expansion index increased and the size and number of pores increased but density decreased with the increasing in $CO_2$ gas injection. Gelatinization degree increased as $CO_2$ gas injection increased. In conclusion, cold extrusion with $CO_2$ gas injection at $60^{\circ}C$ die temperature could be applied for Saengsik (uncooked food) making.

• Journal of the Korean Society of Food Culture
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• v.21 no.3
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• pp.311-318
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• 2006

This study aims to investigate the quality characteristics of breads with the addition of sweet pumpkin powder. Farinogram showed that the absorption rate of the dough decreased, the development time and stability became shortened, and the degree of attenuation tended to be grown along with increasing the amount of pumpkin powder. From the amylogram, it was found that the gelatinization starting temperature and the maximum viscosity of pumpkin powder added dough seemed to be decreased as the amount of pumpkin powder was increased. Extensogram showed that there was a decrease in the degree of extension of the dough added with increasing the amount of pumpkin powder, while an increase in the degree of resistance and resistance/extensibility. The lightness (L value) and redness (a value) of bread was found to be decreased with increasing the amount of pumpkin powder, while the yellowness (b value) increased. In terms of the dough texture, for which the hardness, cohesiveness and gumminess of the dough were measured, there were no significant differences between groups, while the dough added with 8.0% pumpkin powder showed a significant decrease in the elasticity. The results of sensory evaluation showed that the highest score of color (p<0.05) and taste (p<0.05) were obtained from the bread added with 6.0% and 8.0% pumpkin powder, while the highest score of texture in control and 3.0% pumpkin bread. In addition, the highest score of flavor (p<0.05) and overall acceptance (p<0.05) were observed in bread added with 6.0% pumpkin powder. Upon the results of this study, it was assumed that the development of food products using pumpkin are prospective in response to health-oriented consumers.

• Korean journal of food and cookery science
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• v.5 no.2
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• pp.1-8
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• 1989

The physicochemical properties and gel forming properties of mungbean and buckwheat crude starches were investigated. The results were as follows; 1. The granule size and shape of mungbean crude starch were $11~32\mu\textrm{m}$ and oval, and those of buckwheat crude starch were $3~10 \mu\textrm{m}$ and polygonal. 2. The amylose conteut of mungbean crude starch and buckwheat crude starch were 78.0% and 26.4% respectively. 3. The blue value of mungbean crude starch and buckwheat crude starch were 1.030 and 0.409, respectively. 4. Periodate oxidation of mungbean crude starch resulted that amylose had the average molecular weight of 95, 648, degree of polymerization of 590 and amylopectin had the degree of branching of 5.4, glucose unit per segment of 18.6, and periodate oxidation of buckwheat crude starch resulted that amylose had the average molecular weight of 133, 690, degree of polymerization of 825 and amylopectin had the degree of branching of 5.2, glucose unit per segment of 19.2 5. Water binding capacity of mungbean crude starch was 185.1% and that of buckwheat was 209.9% 6. The pattern of change in swelling power of mungbean crude starch for increasing temperature started to increase at $60^{\circ}C$ and increased rapidly from $70^{\circ}C$, and that of buckwheat increased slowly from $60^{\circ}C$ to $90^{\circ}C$ without rapid increase. 7 The ranges of gelatinization temp. of mungbean and buckwheat crude starches were 63. 9-$109^{\circ}C$ and 52.5-84.$2^{\circ}C$, respectively. 8. The gelatinization patterns for 6% munbean crude starch and 8% buckwheat crude starch were investigated by Brabender amglograph. Mungbean crude starch showed the initial pasting temperature of 77.6$^{\circ}C$ without peak height, and buckwheat crude starch showed that of $62.5^{\circ}C$ without peak height. In addition, sensory evaluation for sample starch gels (mungbean, buckwheat, cowpea) was done. 1. The difference of sensory characteristics for each starch gel was significant. 2. The sample starch gels were regarded as 'Mook' by pannels. 3. 74.44% of the degree of Mooklike was explained by hardness.

• The Korean Journal of Food And Nutrition
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• v.15 no.4
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• pp.321-325
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• 2002

For examination, amaranth was first dried its surface after sufficient soaking in water. Dried amaranth was roasted when the moisture contents reached 30∼50%, its nasty smell disappeared and its color turned to yellow and it was puffed. Pretreated amaranth was added to biscuit for the improvement of apparence and merchandise value. The maximum expansion was reported at the moisture percentage of 130∼160% according to the examination of expansion and moisture percentage. In order to compare gelatinization of different processing, three different amaranth were prepared as follows ; Raw amaranth, steamed/dried amaranth, and roasted amaranth. The degree of gelatinization was increased as the percentage of moisture was increased and the degree of gelatinization of roasted amaranth was higher than the one of steamed/dried amaranth, their moisture contents were 62.10% and 57.59%, respectively In addition, the hardness($\times$10$\^$5/dyn/㎠) of roasted amaranth was showed lower values than that of steamed amaranth and raw amaranth were showed the large values. After examining biscuits containing each amaranth, raw amaranth had problem with nasty smell and bad texture, and streamed/dried amaranth were able to remove viscosity but turned brown. Biscuits containing roasted amaranth had good smell and texture, and besides the color of biscuits became bright because roasted amaranth turned white. Biscuits tasted best when it contained 5% of roasted amaranth. The rancidity of biscuits with 5% roasted amaranth were proceeded slowly while roasted amaranth itself had high acid value and peroxide value. For the safety from oxidation, it was fairly safe for about 6 months.