• Korean journal of food and cookery science
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• v.22 no.2 s.92
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• pp.147-157
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• 2006

To improve the properties of non-waxy rice flours for baking, soaked-wet milled rice flour (SWRF) was adjusted moisture content (MC) to 30 and 50 % and heated at 50 and $70^{\circ}C$ in a shaking water bath for 6 and 18 hrs, respectively. Moisture-heat treated rice flours were investigated with regard to particle size distribution, and morphological, physicochemical and pasting properties for comparing dry and wet milled flours. The particle size of rice flour treated with 30% MC was distributed between $4-20{\mu}m\;and\;100-200{\mu}m$, like SWRF. The particles above $200{\mu}m$ in the flour were produced at higher heating temperature. By SEM, starch granules were found in the rice flours treated with 30% MC, who whereas aggregated starch granules were shown in the flours treated with 50% MC. Moisture-heat treatment using higher MC and heating temperature decreased the lightness and increased the yellowness of non-waxy rice flours. Water binding capacity of 30% moisture treated rice flour was similar to that of SWRF. In the same moisture treated rice flour, swelling power was higher, but solubility was lower at $50^{\circ}C$ than at $70^{\circ}C$. The initial pasting temperature by RVA increased after moisture-heat treatment. The peak viscosity of moisture-heat treated rice flour was higher for 30% moisture than that of the others. The rice flour treated with 30% MC and heated at $50^{\circ}C$ showed low setback and increased stability for retrogradation.

• The Korean Journal of Food And Nutrition
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• v.32 no.4
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• pp.355-363
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• 2019

This study was conducted to explore the quality characteristics of colored rice depending on the cultivars (Jeogjinu, Josaengheugchal, Joeunheukmi, Heukjinjubyeo, Hongjinju, Heukjinmi, Geongganghongmi) for porridge. The moisture, crude protein, lipid, ash, amylose and damaged starch contents of colored rice ranged from 10.05~11.23%, 7.72~8.69%, 2.68~3.26%, 1.62~1.88%, 6.29~20.31% and 5.06~8.26%, respectively. The highest moisture (11.23%), crude protein (8.69%), lipid (3.26%) and ash (1.88%) contents of colored rice were detected in Heukjinjubyeo, Joeunheukmi, Josaengheugchal and Heukjinmi, respectively. The lowest amylose and damaged starch contents of colored rice were detected in Josaengheugchal and Joeunheukmi, respectively. In general, the water binding capacity, water solubility and swelling power of Heukjinmi were greater than those of the other cultivars. The investigation of the pasting properties (peak, trough, break down, final and setback viscosity, peak time, pasting temperature) of colored rice indicated a low value in Josaengheugchal. The lowest hardness (13,673.25 g) of colored rice was observed in Heukjinjubyeo while the highest digestibility (5.44 glucose mg/g) of colored rice was observed in Josaengheugchal. These results indicated that Josaengheugchal are suitable cultivars for porridge.

• Korean journal of food and cookery science
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• v.10 no.4
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• pp.405-411
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• 1994

This study was conducted to know the quality of chou made with flour pastes which were stored at different conditions of quick freezing, slow freezing, cold and room temperature. Also, this study included investigation of the chou properties such as expansion, sensory evaluation, degree of gelatinization, and physical and structural properties of paste were observed. There were not significant differences m diameter, height, volume, appearance, hollow formation, and sensory evaluation between the chou made with the paste stored at freezing condition and chou directly baked after pasting. Quick and slow freezing storages did not significantly affect the properties of chou, and the same results were obtained among the chou made with pastes thawed at room temperature and in microwave ovenrange. The chou of pastes stored at room temperature and in microwave ovenrange. The chou of pastes stored at room temperature and stored in refrigerator showed lowed expansion and value of sensory evaluation than those of frozen pastes. The paste stored at room temperature had the lowest hardness and viscosity compared with the other storage conditions. According to the observation of light microscope. the lipid bodies of the paste of freezing storage smaller those of the room temperature and refrigerator storage. The expantion of chou made with paste stored at room temperature was greatly decreased due to the high coalescence of lipid bodies, and also the paste components such as lipid, starch granule gluten at room temperature had inferior dispersion condition. The general tendency of the degree of gelatinization of chou were low in all treatments of paste. The values were 23.5%~46.0% in freezing, 77.3% in room temperature, 68.7% in directly baked after pasting, and 61.0% in cold storage, respectively. The formation and the taste of chou made with frozen paste were similar to those of chou directly baked pasting.

• Journal of Microbiology and Biotechnology
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• v.24 no.2
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• pp.254-263
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• 2014

Enteromorpha polysaccharides (EP) extracted from green algae have displayed a wide variety of biological activities. However, their high molecular weight leads to a high viscosity and low solubility, and therefore, greatly restrains their application. To solve this problem, bacteria from the surface of Enteromorpha were screened, and an Alteromonas macleodii strain B7 was found to be able to decrease the molecular weight of EP in culture media. Proteins harvested from the supernatant of the A. macleodii B7 culture were subjected to native gel electrophoresis, and a band corresponding to the Enteromorpha polysaccharide lyase (EPL) was detected by activity staining. The enzyme identity was subsequently confirmed by MALDI-TOF/TOF mass spectrometry as the putative ${\alpha}$-amylase reported in A. macleodii ATCC 27126. The amylase gene (amySTU) from A. macleodii B7 was cloned into Escherichia coli, resulting in high-level expression of the recombinant enzyme with EP-degrading activity. AmySTU was found to be cold-adapted; however, its optimal enzyme activity was detected at $40^{\circ}C$. The ${\alpha}$-amylase was highly stable over a broad pH range (5.5-10) with the optimal pH at 7.5-8.0. The highest enzyme activity was detected when NaCl concentration was 2%, which dropped by 50% when the NaCl concentration was increased to 16%, showing an excellent nature of halotolerance. Furthermore, the amylase activity was not significantly affected by tested surfactants or the presence of some organic solvents. Therefore, the A. macleodii strain B7 and its ${\alpha}$-amylase can be useful in lowering EP molecular weight and in starch processing.

• Food Quality and Culture
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• v.3 no.1
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• pp.1-5
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• 2009

The objective of this study was to develop a reliable and reproducible descriptive analysis procedure for Korean style sweet pumpkin gruel (Hobakjuk). The sensory attributes of the sweet pumpkin gruel were developed and defined, the sample preparation method was standardized, and the sensory evaluation procedure for a sample was established. Seven types of sweet pumpkin gruel (five ready-to-eat type vs. two ready-to-heat type) were selected to be analyzed. Panel training and descriptive analysis were carried out with these 7 samples. A total of 12 sensory attributes (2 aroma/odor, 5 taste/flavor, 4 texture/mouthfeel, and 1 aftertaste attributes) were developed to describe the sensory characteristics of the sweet pumpkin gruel. The definition and reference standards for each sensory attribute were determined to clearly understand each attribute. In the main experiment, trained panelists evaluated the sensory characteristics of the 7 gruel samples based on a fifteen-point intensity scale using the developed attributes. The results were statistically analyzed by analysis of variance, principal component analysis, and cluster analysis. The results showed that the 7 sweet pumpkin gruel samples significantly differed in their intensities of all attributes except for sweet pumpkin aroma and viscosity. The ready-to-eat style samples were distinctly characterized by their sweet pumpkin aroma and flavor, whereas the ready-to-heat style samples were markedly characterized by their low intensity of gelatinized starch and pumpkin flavor retention.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.4
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• pp.459-467
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• 2013

This study was conducted to investigate the effects of substituting whole barley flours on quality characteristics of noodles. Noodles were made with composite flour containing 20% whole barley flour of various hullless barley cultivars and the quality characteristics, ${\beta}$-glucan content and antioxidant characteristics were investigated. In amylogram characteristics, the initial pasting temperature and peak viscosity were increased, and setback was decreased in complex flour. Noodles containing barley flour had low lightness, yellowness and high redness compare to wheat noodle. Water absorption of cooked noodles was lower than wheat noodle. The value of swelling index was high in noodles containing non-waxy barley flour and low in noodles containing waxy barley flour. Hardness and gumminess of noodles were lower than wheat noodle. Noodles containing non-waxy barley had higher hardness, cohesiveness and gumminess than noodles containing waxy barley flour. Dahan, non-waxy barley cultivar showed similar characteristics with the wheat noodle. ${\beta}$-Glucan content and antioxidant activity were increased with adding barley flour. Cooked noodle had slightly high ${\beta}$-glucan content, low starch content and low antioxidant activity compared to value of uncooked noodle.

• The Korean Journal of Food And Nutrition
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• v.30 no.6
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• pp.1260-1267
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• 2017

The properties of rice were studied on five rice cultivars (Ilpumbyeo, Samkwang, Goami-4, Dodamssal, and Thai rice), and employed two kinds of saccharification treatment methods (treatment I : rice shape, treatment II: grinding rice shape). Thai rice showed differences in width and length when compared to other cultivars of rice, and the Goami 4 had the lowest thousand-grain weight. The Goami4 and Dodamssal each showed high contents of amylose and resistant starch, and the water absorption rate was close to maximum at 90 minutes as well as the highest level of Goami 4 at all times. The qualities of highest water-binding capacity, solubility and swelling power was most significant in Thai rice. The lowest hardness level of wet rice resulted in the lowest hydration-related characteristics. High amylose content rice, in particular, showed low sugar content and slightly increased sugar content as the saccharification process improved (treatment II). On the other hand, high amylose cultivars had the same high degree of hardness as boiled rice. From these results, the Dodamssal was found to have the lowest viscosity at all temperatures but highest viscosity during the saccharification process, suggesting it may be successfully implemented as a thickener in rice beverage processing. The purpose of this study was to attempt to provide basic data on the development of rice beverage manufacturing technology, based upon the quality characteristics related to beverage processing of rice cultivars.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.3
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• pp.212-218
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• 2011

This study was performed to determine the relative quality of mungbeans harvested in bulk after applying a labor-saving cultivation (LSC) method, compared to mungbeans harvested three different times under the conventional cultivation condition. There was no significant difference in starch, crude protein, and vitexin or isovitexin content of seed according to the cropping system or harvest time. The mungbeans grown under the LSC method had the highest crude fat content, followed by mungbeans from the third-, the second- and the first-harvest mungbeans under the conventional cultivation. No significant difference was found in the composite ratio of saturated fatty acids to unsaturated fatty acids according to cropping system or harvest time. The second-harvest mungbeans grown under the conventional cultivation condition had 17 different types of fatty acids, while the third-harvest mungbeans grown under the conventional cultivation and those grown under the LSC condition had the fewest types of fatty acids with 12. Of the major saturated fatty acids, palmitic acid and arachidonic acid had the highest composite ratio in the first conventional cultivation followed by the second, the third and the LSC. However, stearic acid showed the opposite tendency. Of the major unsaturated fatty acids, linoleic acid had the highest composite ratio in the first conventional cultivation, followed by the second and third conventional cultivation and the LSC. Amylogram characteristics of the mungbeans were significantly different according to cropping system and harvest times. The mungbeans harvested after the first conventional cultivation had significantly higher pasting temperature, peak viscosity, holding strength viscosity, final viscosity and breakdown, while mungbeans harvested after the third conventional cultivation had significantly higher setback viscosity. In contrast, the mungbeans harvested under the LSC methods had a significantly lower amylogram value. When harvest rate, color values and amino acid content of sprout were measured, mungbeans grown under the LSC conditions had a low harvest rate of sprout, but had Hunter's color values and amino acid content of sprout similar to those of mungbeans grown under the conventional cultivation condition.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.4
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• pp.424-431
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• 2013

Consumption of waxy corn is steadily increasing due to consumer preference for natural food. However, availability of waxy corn is limited because most of them are used for steamed waxy corn. It is therefore important to create new demands of waxy corn using food processing technology. There is little prior research about characteristics of milled kernel in waxy corn. This study examined the physicochemical and cooking properties of milled kernel using nine waxy corn hybrids. Colored hybrids (Heukjinju, Miheukchal, and Eolrukchal1) showed high milling yield and low change of grain length after milling process compared to other hybrids. The total starch content ranged from 62.1 to 68.4% and the gelatinization temperature of starch was lowest in Yeonnong1 ($69.9^{\circ}C$). The breakdown viscosity of Yeonnong1, Miheukchal and Heukjinju was higher than those of tested hybrids, whereas setback viscosity of those hybrids was lower. In cooking properties of milled waxy corn, water absorption and volume expansion rate were high in Yeonnong2 (84.9, 219.3%), Miheukchal (85.9, 211.4%), and Heukjinju (80.9, 203.7%). In the sensory test, the overall preference was significantly higher in Heukjinju and Miheukchal. Thus, Heukjinju, Yeonnong2, and Miheukchal showed good scores in milling yield, cooking properties, and the preference of sensory test. These results will provide fundamental information to extend milled waxy corns usage.

• Korean Journal of Food Science and Technology
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• v.26 no.6
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• pp.670-678
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• 1994

The effects of amylase addition during extrusion cooking of rice on the physico-chemical properties of the extrudates were investigated in order to develop rice-based Korean style weaning food products. A laboratory-built single screw extruder was used, the enzymes used were Termamyl 120LS(amylase from Bacillus licheniformis, NOVO Co.), BAN 240L(amylase from Bacillus amylolichuefaciens, NOVO Co.) and malt powder. By the addition of enzymes, the water soluble index of the extrudates increased by 3 times compared to that of the extrudates without enzyme and the concentration of reducing sugar in the extrudates increased drastically at 28 feed moisture. The gel permeation chromatographic pattern showed that the large molecular starch fractions diminished by the addition of enzyme during extrusion and the low molecular fraction increased. The residual enzyme activity in the extrudate were 27% for the most thermo-resistance enzyme by treating at $140^{\circ}C$ in the metering section of the extruder. The sediment volume of the extrudate dispersion increased as the metering section temperature increased to $140^{\circ}C$ . By the addition of enzymes the viscosity of extrudate dispersion was redused $1/4{\sim}1/200$ of that of the extrudates without enzyme. It allowed to use 1.8 times of solid material to the weaning food formulation to attain the same level of consistency as the commercial products. It proves that the addition of amylase during rice extrusion is effective to increase the energy density of weaning food by starch degradation, which results in the increases of water solubility, reducing sugar content, dispersibility and fluidability.