• Culinary science and hospitality research
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• v.21 no.6
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• pp.218-228
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• 2015

In this study, the physicochemical characteristics of rice sourdough fermented with Omija extract were investigated. Rice sourdough was made with a 3 stage fermentation process. pH & total titratable acidity, numbers of yeast and lactic acid bacteria, and dough expansion rate were measured. In addition, an RVA was employed to study the pasting properties of rice sourdough. There was a significant (p<0.05) change in both the pH of rice sourdough, which decreased from 5.08 to 3.98, and total titratable acidity, which increased from 0.20 to 0.57 (0.1N NaOH mL), as fermentation time increased. The amount of yeast and lactic acid bacteria significantly increased from 6.73 to 7.65 log CFU/g, 6.93 to 7.65 log CFU/g, respectively(p<0.05). The expansion rate of rice sourdough fermented with Omija extract was higher than rice sourdough fermented without Omija extract. The initial pasting temperatures of rice sourdough fermented with Omija extract were decreased from $91.3^{\circ}C$ to 85.6. The final viscosity and setbacks decreased as fermentation time increased. These results suggest that Omija extract has a beneficial effect on increasing the expansion rate of rice sourdough as a substitute for wheat flour.

• Culinary science and hospitality research
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• v.20 no.2
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• pp.100-119
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• 2014

In this study, rice was used with naturally fermented extract to compare and analyze the physico-chemical characteristics and investigated how to make pan bread made with domestic wheat flour added with naturally fermented rice extract. Also, it examined quality characteristics of pan breads prepared with 0, 10, 30, 50, 70% naturally fermented rice starters. As the fermentation time of rice starters increased, pH of bread doughs decreased. On farinograph, water absorption, development time and stability of rice starters samples were lower than the control. RVA(Rapid Visco Analyzer) analysis showed that wheat flour retrogradation was retarded by increasing rice starters content. The weights of pan breads containing rice starters were higher than that of control. The moisture content of pan breads containing rice starters decreased as storage time increased. In analyzing of visible mold colony during 7 days of storage at $28^{\circ}C$, pan breads containing rice starters was retarded mold growth. In the texture analyzer measurement, hardness of breads containing rice starters significantly increased as storage time increased, which was higher than that of control. The result of sensory properties was no significant difference between the group containing 50% naturally fermented rice starters and control group, such as appearance, flavor, taste and overall quality.

• Korean Journal of Food Science and Technology
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• v.48 no.2
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• pp.165-171
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• 2016

Physicochemical properties of waxy maize flours prepared by hydrothermal and enzymatic treatments were evaluated. Waxy maize flours were hydrothermally treated using heat-moisture treatment (HMT) and annealing (ANN) and enzymatically treated using commercial enzymes (cellulase, proteinase, and pectinase). The HMT-modified waxy maize flours had low water absorption index (WAI), melting enthalpy, viscosity, and crystallinity. However, ANN-modified and enzymatically modified waxy maize flours had high WAI, melting enthalpy, and viscosity. X-ray diffraction analysis of ANN-modified and enzymatically modified waxy maize flours revealed a typical A-type pattern and displayed sharper crystalline peaks than those observed for the control groups (native waxy maize flours). In contrast, the crystallinity of HMT-modified waxy maize flours were decreased by hydrothermal treatment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.11
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• pp.1742-1748
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• 2014

This study investigated the quality characteristics of commercial rice flour (CRF) and rice flours prepared by different milling methods for sulgidduk. For particle distribution, dried rice flour after the 1st roll mill using a pin mill showed a particle size of greater than $710{\mu}m$, whereas a particle size less than $250{\mu}m$ accounted for 48% of whole rice flour. This proportion was higher than CRF after the 2nd step roll mill. Crude protein, lipid, and ash contents were significantly highest in 1st roll mill samples. For color, roll & pin made up of many small particles showed a high L value. CRF and roll & pin showed significantly higher starch damage and water-holding capacity, whereas pasting temperature, peak viscosity, and setback of RVA pasting characteristics were lower than 1st roll mill. When rice cakes were made from three kinds of rice flour, roll & pin was not significantly different compared to the CRF. However, rice cakes made with 1st roll milled rice flour showed rough crumb and crust. Rice cake made with roll & pin or CRF showed similar characteristics for texture. In the quantitative descriptive analysis, rice cake made with roll & pin showed better appearance, flavor, taste, texture, and overall acceptability than CRF and 1st roll mill. Therefore, rice flour prepared by roll & pin could be applied to sulgidduk with high quality.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.7
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• pp.900-907
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• 2008

The physicochemical properties of black rice flours produced from dry and wet milling were carried out to investigate their applications in food processing industry. The dry milled black rice flours showed lower fat, protein, ash, and anthocyanin contents than those of wet milled black rice flours with no effect due to number of millings. Average particle sizes ($379{\sim}288\;{\mu}m$) of dry milled flours were bigger than those ($336{\sim}253\;{\mu}m$) of wet milled flours. Particles with 60 mesh or more increased with increasing milling times. Wet milled flours had higher damaged starch, water solubility index (WSI), and water absorption index (WAI) compared to dry milled flours. Pasting properties measured by rapid visco analyzer (RVA) resulted in higher pasting temperatures in dry milled flours ($62.5{\sim}69.4^{\circ}C$) than wet milled flours ($46.1{\sim}46.4^{\circ}C$). As the number of milling times increased, pasting temperature of wet milled flours were not effected. Dry and wet milling resulted in reduced trough, final viscosity, and consistency with increasing milling times.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.spc1
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• pp.77-83
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• 2006

This study was carried out to investigate the agronomical and physicochemical properties of five newly bred sugary lines in YARI (Yeongnam Agricultural Research Institute) that developed from the cross of sugary and Hwayeongbyeo, Hwasambyeo and Seomjinbyeo. Culmlength of newly bred sugary lines were longer than that of Nampyeongbyeo as $84.2{\sim}99.3cm$. However the weight of 1,000 grains and yield were lower than that of Nampyeongbyeo by two to three times. According to physicochemical properties, most of the new bred sugary lines showed low contents of amylose and mineral compare to normal varieties. And all sugary lines showed much higher amount of the sucrose and glucose contents compare to Nampyeongbyeo. Especially the sucrose content of newly bred sugary line, 55413, was 5 times higher than that of Nampyeongbyeo nevertheless, fructooligosaccharide and isomaltooligsac charide were not detected. The amylopectin constitution of sugary lines showed more chairs of DP (Degree of Polymerization)<12 but fewer chains of DP $13{\sim}24$ compare to Nampyeongbyeo. Newly bred sugary lines were lower viscosity in RVA (Rapid Viscosity Analysis).

• Korean journal of food and cookery science
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• v.18 no.5
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• pp.534-542
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• 2002

This study was carried out to determine the effects of various starches (mungbean starch, cowpea starch and corn starch) on the quality characteristics of Omija jelly made of Omija extract. The viscosity of starch suspended in Omija extract and distilled water was measured by using a RVA(Rapid Visco Analyzer), and, color value, syneresis, texture(rupture test and TPA test) and sensory properties of Omija jelly and pure starch jelly were measured. Gelatinization temperature of each starch suspended in Omija extract was higher than that suspended in distilled water, whereas final viscosity of Omija jelly was decreased. Omija extract appeared to retard the gelatinization of starch and recrystallization of gelatinized starch. The viscosity of com starch was lowest among the three types of starch, suggesting thai higher concentration is needed in the use of com starch. The lightness(L) of corn starch gel was the highest among the gels. The syneresis of Omija jelly was lower than that of starch jelly, therefore, Omija extract seemed to be helpful on the stability of starch gel. Rupture properties of Omija jelly was lower than that of starch jelly, whereas the adhesiveness of omija jelly was greater. Omija jelly made of corn starch was less cohesive and more sticky than other gels, and its acceptability was very low. Sensory characteristics of the gel were relatively well correlated with the mechanical characteristics. Overall acceptability of Omija jelly was high in the concentration of 7, 8% of mungbean starch and 8, 9% of cowpea starch. Thus, the optimum concentration of starch for making Omija jelly using mungbean starch was 7, 8% and that using corn starch was 8, 9%.

• Korean Journal of Food Science and Technology
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• v.36 no.4
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• pp.568-573
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• 2004

Effects of dry heating and pH on pasting, thermal, and textural properties of corn starch containing soy protein isolate (SPI) were investigated. Samples were prepared by drying corn starch dispersions containing 3% SPI at $40^{\circ}C$ (unheated sample) or additionally heating dried mixtures at $130^{\circ}C$ (heated sample). Pasting properties of starch samples and textural properties of starch gels were measured using Rapid Visco-Analyzer (RVA) and Texture Analyzer (TA), respectively. Effects of SPI addition and dry heating on retrogradation and microstructure of gel samples were investigated using DSC and SEM, respectively. Pasting viscosity of dry-heated samples was significantly higher than that of unheated samples, and at pH 8 compared to pH 6. Dry-heat treatment decreased fracture stress and strain of starch gels containing SPI. No significant effects of dry-heat treatment and pH were observed on retrogradation of starch gels. Addition of SPI retarded starch retrogradation and modified starch gel properties with increased nutritional value. Dry-heat treatment with SPI could be possible method for starch modification.

• Culinary science and hospitality research
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• v.17 no.3
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• pp.172-180
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• 2011

This study explores the quality characteristics of white pan bread added with perilla leaf powder, and the results are as follows. The WRC(water retention capacity) of PLP (perilla leaf powder) added to the bread dough increased as the addition increased, and the initiation temperature during the rapid visco analysis (RVA) increased with more additions, showing significant differences. The highest and the lowest viscosity of the sample decreased as the powder added increased. The brightness(L value) of the bread without the powder was the highest, and the redness (a value) and the yellowness (b value) showed significant differences among the samples. Hardness increased showing significant differences among the samples as the powder added increased Chewiness was the highest but preference value was the lowest in the sample with 7% of the powder. The lowest score was shown in the color of the sample with the most PLP added. Flavor was the lowest of 4.93 in the comparison sample without the leaf powder added while bitter taste scored the highest of 5.21 in the sample of 3% powder added. It was also the highest in overall acceptance while the sample with the most powder showed the lowest of 4.03. From these results, it can be said that the preference of bread with PLP seems to decrease when more than 5% of PLP is added.

• Korean Journal of Food Science and Technology
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• v.38 no.3
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• pp.385-391
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• 2006

Physicochemical properties of hydroxypropylated waxy rice starches were investigated to reduce steeping-time of yukwa (Korean oil-puffed rice snack) processing. Swelling power of hydroxypropylated waxy rice starch increased at relatively higher temperature $(60^{\circ}C)$ than native waxy rice starch $(70^{\circ}C)$. Solubility of hydroxypropylated waxy rice starches increased with increasing propylene oxide content. Pasting temperature $(66.3-66.9^{\circ}C)$ and peak viscosity (216-232 RVU) of hydroxypropylated waxy rice starch were higher than those of native starch (179 RVU) and increased with increasing propylene oxide content. DSC thermal transitions of hydroxypropylated waxy rice starches shifted toward higher temperature. Amylopectin melting enthalpy of hydroxypropylated waxy rice starch (8.4-9.2 J/g) was similar to native starch (9.0 J/g). X-ray diffraction patterns of native and hydroxypropylated waxy rice starches showed typical A-type pattern with no significant differences between them, suggesting hydroxypropylation only affected amorphous region. Results suggest hydroxypropylated waxy rice starch is not applicable for yukwa due to low puffing efficiency and dark color.