• Korean Journal of Food Science and Technology
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• v.33 no.1
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• pp.157-160
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• 2001

RS yields and swelling powers of cross-linked RS 4 starches and effects of RS 4 starches on the pasting profiles of RS 4 added wheat starch were measured using RVA. RS yields by AOAC method were different among RS 4 starches and RS levels were higher in low swelling RS 4 starches than moderate swelling RS 4 starches. Swelling power was different with botanical source of starch and preparing procedure of RS 4 starches. The pasting curves of RS 4 added wheat starches showed increasing initial pasting temperature and lower viscosity but the patterns were similar to those of wheat starch. The pasting viscosity pattern of RS 4 added wheat starches was related with swelling power of RS 4 starch.

• Preventive Nutrition and Food Science
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• v.17 no.1
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• pp.87-91
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• 2012

Three oat cultivars and one oat breeding line were evaluated for chemical, hydration and pasting properties. Protein, starch and ${\beta}$-glucan levels ranged 11.13~14.37, 56.37~64.86 and 3.44~4.76%, respectively. The oat cultivars Daeyang and Seonyang contained higher ${\beta}$-glucan levels of 4.76 and 4.35%. The Daeyang variety had a higher water absorption index (WAI) of 2.83~3.35 (g/g), but a lower water solubility index (WSI) of 8.67~11.08%. Daeyang and Seonyang cultivars showed higher peak and trough viscosity, but lower breakdown and setback, indicating that they easily swell, and thus could possibly provide the desirable viscosity of an oat product. The ${\beta}$-glucan levels were correlated positively with WAI, peak and trough viscosity, and negatively to WSI, breakdown and setback viscosity.

• Korean Journal of Food Science and Technology
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• v.46 no.2
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• pp.135-142
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• 2014

Physicochemical, pasting, and digestion properties of sweet potato starches from 11 Korean cultivars were investigated. Starch granules were variably oval, round, polygonal, spherical, and bell-shaped, and of 10.2-15.3 ${\mu}m$ in mean particle diameter. Amylose contents varied from 12.3 to 17.4%. A similar chain length distribution of amylopectin was found in each of the cultivars. The portion of $B_3$ correlated with the degree of amylose leaching. Thermal properties determined by differential scanning calorimetry showed high values of gelatinization temperatures in Shinyulmi and Jeungmi starches, but a relatively low value in Daeyumi starch. All starches exhibited a Ca-type diffraction pattern. Differing patterns were observed in swelling factors, depending on temperature. The contents of rapidly digestible starch, slowly digestible starch, and resistant starch ranged from 9.6-17.4, 31.4-45.6, and 35.7-62.8%, respectively. In Rapid Visco Analyser profiles, differences were observed in pasting parameters such as pasting temperature, peak viscosity, final viscosity, and breakdown.

• Preventive Nutrition and Food Science
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• v.10 no.3
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• pp.207-213
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• 2005

Molecular structures and functional properties of starches isolated from normal, waxy, and zero amylose barleys were examined. Amylopectins from zero amylose starch had the largest molecular weight $(M_w)$, whereas those from high amylose starch, the smallest. A good correlation between the $(M_w)$ and the radius of gyration $(R_g)$ was observed among amylopectins from various starches, indicating similar polymeric conformation in solution even with the differences in the $(M_w)$. The debranched amylopectin molecules from different types of barley starches exhibited similar profiles, implying that the packing geometry of double helices in the different types of barley starches may be similar. Zero amylose starch showed the highest peak viscosity (326 RVU) in RV A viscograms at lower pasting temperature $(67.6^{\circ}C)$, compared to normal and high amylose starches. Relationship between RVA peak viscosity and amylose content suggested that the presence of amylose inhibited the development of granular swelling of barley starches during cooking. A rapid retrogradation, traced by differential scanning calorimetry (DSC) and strain-controlled rheometry, occurred in the high amylose starch sample during storage, while zero amylose starch showed a very good resistance to retrogradation, indicating excellent storage stability.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.4
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• pp.441-451
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• 2019

This study was conducted to investigate the crop characteristics of 181 sweetpotato germplasms collected from Korea and overseas. The longest shoot vine length was observed in IT232211 (354.8 cm) and the shortest shoot vine length was observed in IT232185 (32 cm). The maximum numbers of shoot branches and nodes were produced by IT232091 (23.0) and IT232174 (67.8), respectively. Differences in Rapid Visco Analyser profiles were observed for pasting parameters such peak, trough, final, breakdown, and setback viscosities; and pasting temperature. The peak and breakdown viscosities were highest in IT232050 and IT232010, at 338.3 and 207.2 Rapid Visco Unit (RVU), respectively. The trough viscosity was lowest in IT232019 at 103.8 RVU. IT232101 had the highest final viscosity (284.6 RVU), and IT232192 had the highest setback viscosity (81.7 RVU). IT232197 had the highest pasting temperature at 86.8℃, and that of IT232134 was lowest at 72.7℃. To evaluate functional substance content, we analyzed 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and total polyphenol content. The highest frequency proportion of starch was in the 10%-15% range (50.8% of the plants), followed by the 5%-10% range (38.1% of the germplasms). Sugar content ranged from 13.5 to 33.3% (23.2% on average); the highest frequency proportion of sugar was in the 20%-25% range (56.9% of the germplasms), followed by the 25%-30% range (25.4% of the germplasms). The highest frequency proportion of water was in the 70%-80% range (52.5% of the germplasms), followed by the 60%-70% range (44.2% of the germplasms). Our results provide basic data for the selection of useful resources and for the development of new sweetpotato varieties.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.4
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• pp.533-538
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• 2012

The retrogradation properties of a Korean rice cake ($Karedduk$) added with oligosaccharides after 0~30 hr of storage at $5^{\circ}C$ were examined by texture profile analysis and the Avrami equation using textural characteristics. Oligosaccharides, such as galactooligosaccharide (50%) and maltooligosaccharide, were added to dry rice flour at levels of 10%. In the amylogram, the breakdown (P-H) and consistency (C-H) of the Korean rice cake (Karedduk) added with oligosaccharides were lower than those of the control. Texture profile analysis using a Texture Analyzer revealed that the hardness of the Korean rice cake ($Karedduk$) added with oligosaccharides was lower than the control. The Avrami exponent ($n$) for the control, galactooligosaccharide (50%) 10% and maltooligosaccharide 10% addition was 2.415, 2.771 and 2.683, respectively. The time constant (1/$k$) for galactooligosaccharide (50%) 10% or maltooligosaccharide 10% addition was higher than the control. Overall, adding galactooligosaccharide (50%) 10% or maltooligosaccharide 10% to a Korean rice cake ($Karedduk$) is effective in retarding retrogradation.

• Korean journal of food and cookery science
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• v.26 no.6
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• pp.677-684
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• 2010

The purpose of this study was to investigate the effects of black foods (black rice and black garlic) and the ratio of black garlic on the quality of Sulgiddeok. Pasting properties as measured by a rapid visco analyzer (RVA) were lower for black rice flour than white rice flour. Colorimetric analysis revealed that L, a, b values were dependent on the type of rice. For texture profiles, texture was associated with RVA profiles. During storage, hardness of black rice Sulgiddeok increased to a lesser degree than that of control. After observation via scanning electron microscopy (SEM), black rice Sulgiddeok showed a honeycomb-like network structure. In sensory analysis, black rice Sulgiddeok showed a tendency to prefer the control. The addition of appropriate black garlic (BG1) helped to improve the quality. In accordance with the aforementioned results, decreased retrogradation related to black rice Sulgiddeok and black foods (black rice and black garlic) could result in quality products with high nutritional value.

• Korean Journal of Food Science and Technology
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• v.22 no.7
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• pp.753-761
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• 1990

The physicochemical properties of starches from aerial and subterranean tuber of yam were compared with those of rice and sweet potato. Aerial tuber yam contained higher level of amylose than others, whereas water binding capacity, swelling power and solubility was highest in subterranean tuber yam starch. Brabender amylograms of 5% starch suspensions indicated that the initial pasting temperature of yam starches were slightly higher than that of rice and sweet potato starches, the maximum viscosities of starches from subterranean and aerial tuber yam were 860 and 590 B.U., respectively. Yam starches were more difficult to hydrolyze by ${\alpha}-amylase$ than rice and sweet potato starches. ${\beta}-Amylolysis\;limit$ for yam starches and their amylose and amylopectin were higher than rice and sweet potato starches. The elution profiles of starches on Sepharose CL-2B were different from each other but they were similar between yam starches. Incomplete debranched fractions in the aerial tuber yam amylopectin was particularly higher than other samples. The weight ratio of short chains to long chains for debranched amylopectins was the lowest in aerial tuber yam.

• Korean Journal of Food Science and Technology
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• v.51 no.4
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• pp.348-355
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• 2019

This study investigated the impact of cellulase treatment on the extraction yield of potato starch (PS), and compared the physicochemical properties of PS by conventional (CSE) and enzymatic (ESE) starch extraction. In ESE, the PS extraction yield was predominantly influenced by reaction temperature, time and their interaction, compared to the cellulase concentration. When potatoes were treated for 8 h at $40^{\circ}C$ with 1.5% cellulase, the PS extraction yield was about 3.4-fold higher than that by CSE. Compared to CSE-PS, ESE-PS showed lower total starch contents and higher amylose contents, resulting in lower swelling factors and distorted pasting viscosity profiles accompanied by absence of peak and breakdown viscosities. However, ESE did not affect the gelatinization characteristics of PS. Overall results suggested that ESE can provide the highest yield of PS, and ESE-PS can be a potential starch source for extending the utilization of PS in food industries.