• Applied Biological Chemistry
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• v.30 no.3
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• pp.242-249
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• 1987

Physicochemical properties on heat-moisture treatment of sweet potato starch were investigated. Starch granules of sweet potato observed by photomicroscope, polarized-light microscope and scanning electron microscope were round and polygonal. X-ray diffraction pattern was changed from Ca-pattern to A-pattern upon heat-moisture treatment. Water binding capacity was drastically increased as the moisture level was increased. The swelling power and solubility at the same temperature were decreased by heat-moisture treatment. Transmittance of 0.1% starch suspensions was increased rapidly from $65^{\circ}C$ in case of untreated starch and from $70^{\circ}C$ in case of treated starch. The starch on heat-moisture treatment was gelatinized over higher temperature range than the untreated starch.

• Applied Biological Chemistry
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• v.30 no.2
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• pp.133-140
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• 1987

The physicochemical properties and characteristics of potato starches which were isolated from the six varieties were investigated. The ash content of starch prepared from the Arkula showed lower than that of the other five samples. The shapes of starch granules were oval and round, and the average diameters were in the range of $25{\sim}26.9$ microns. The main constituents of the inorganic components of each starch sample were found to be phosphorus and potassium. The amylose contents of starches were between $27.2{\sim}32%$, and blue value, alkali numbers were in the range of $0.42{\sim}0.45$ and $5.8{\sim}7.7$, respectively. Amylograph data revealed that Nook Sack had the highest viscosity at all reference points. The swelling power and solubility patterns were negligible until $50^{\circ}C$, thereafter it increased rapidly.

• Applied Biological Chemistry
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• v.30 no.1
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• pp.24-30
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• 1987

starches, isolated from Japonica and nonwaxy rites, were analyzed fur gelatinization characteristics. Amylose contents of Taebaeg and Sangpung starch were 16 and 17%, respectively. The portion of large-sized particles was more pronounced in the case of Sangpung starch. Swelling power and solubility increased according to the rise in gelatinization temperature. The decrease of pasting temperature according to the incense in starch concentration in Sangpung starch was higher than that of Taebaeg starch. Most of the increase in light penetration was accomplished between 85 and $90^{\circ}C$. Gelatinization reactions of Taebaeg and Sangpung starch appeared as 2 different stages up to the gelatinization temperature of $90^{\circ}C$.

• Applied Biological Chemistry
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• v.31 no.4
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• pp.339-345
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• 1988

Physicochemical properties of starch isolated from the naked barley seeds during germination were investigated, The germinated barley seeds showed an apparent increase in amylose component of the starches, and water binding capacities of the starches decreased initially and then increased with longer germination time. The size frequency distribution of starch granules showed that the granules larger than $20.2{\mu}$ in diameter were preferentially degraded, and moreover the rate of degradation was higher than that of granules of any other size. It was apparent that the mean diameter of granules was $12.7{\sim}20.2{\mu}$ at all stages of germination. The results of differential scanning calorimetry, swelling power, solubility and X-ray diffraction patterns of starch granules isolated at various stages of germination showed little changes during germination. Scanning electron microscopy revealed that the starch granules have been damaged extensively by degradative enzymes during germination, but all the starch granules were not degraded uniformly.

• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1216-1220
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• 1999

The effects of low-temperature blanching on the physical properties of chestnut powder were studied. Chestnuts were blanched in water for 15, 30 and 60 min., each at three temperatures viz. $45^{\circ}C,\;55^{\circ}C$ and $65^{\circ}C$. The particle size of chestnut powder was prepared smaller than 60 mesh$(250\;{\mu}m)$. Higher blanching time and temperature increased water binding capacity(WBC) of chestnut powder. Water soluble index(WSI) was the highest for chestnuts blanched at $65^{\circ}C$ for 30 min. As with water binding capacity(WBC), swelling power of chestnut powder increased with increasing blanching time and temperature but solubility showed an reduction by increasing blanching temperature. In Brabender amylographic examination, peak viscosity of chestnut powder showed great change, but the gelatinization temperature showed no significant differences by blanching conditions.

• Applied Biological Chemistry
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• v.39 no.1
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• pp.49-53
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• 1996

Acid-modified starch was prepared by treating a warm aqueous starch suspension with dilute mineral acid$(0.2\;N\;HCl,\;45^{\circ}C,\;20\;mim{\sim}1\;h)$. The swelling power and solubility of acid-modified red bean starches increased and the changes occurred at tower temperature. According to gel chromatography of starches, the amylose and amylopectin moieties of red bean starches were not affected very much by hydrolysis conditions used. The elution profiles of soluble carbohydrate showed that the larger molecules were leached as the heating temperature increased. Total amounts of soluble carbohydrate were increased by acid-modification. The gel strength of acid-modified starches at each temperature increased, whereas cohesiveness decreased in acid-modified starch gels except at $85^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.545-550
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• 2003

The effect of ${\beta}-glucan$ on gelatinization of barley starch was studied. By the rapid visco-analyzer measurement, gelatinization of starch became rapid and viscosity increased largely on the RVA pattern by addition of ${\beta}-glucan$ to starch. The results of differential scanning calorimeter showed that molecular structure of starch was getting stabilized through shifting up of gelatinization temperature and increase in enthalpy by addition of ${\beta}$-glucan. X-ray diffraction pattern also showed the same results as differential scanning calorimeter. But it was revealed that addition of ${\beta}$-glucan to starch didn't affect characteristics such as microscopic observation, solubility, swelling power, and iodine binding properties during gelatinization of starch.

• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.268-275
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• 2004

Effects of soaking time and particle size on physicochemical properties of nonwaxy rice flour were investigated. Nonwaxy rice grains were soaked at $4^{\circ}C$ for 0, 1, 12, and 24 hr, dried at room temperature, and milled, Resulting flours were passed through 45-mesh ($<355{\mu}m,\;IL45$) and 100-mesh ($<150{\mu}m\;IL100$) sieves and separated into $<40{\mu}m\;and\;40-100{\mu}m$ series. IL45 series showed higher amount of large particles ($40-100{\mu}m$) than IL100 series. As the soaking time increased, protein and ash contents decreased, and amylose content, water-binding capacity, swelling power, and solubity of nonwaxy rice flours increased. Swelling power and solibility of nonwaxy rice flours also increased between $65-85^{\circ}C$. Water-binding capacity, swelling power, and solubility of IL100 series were higher than those of IL45 series. 12 hr-soaked nonwaxy rice flour pastes showed higher peak viscosity and breakdown but lower setback and visicosity at $95\;and\;50^{\circ}C$ than 1 hr-soaked ones. X-Ray diffractograms of nonwaxy rice flours were not affected, whereas surface appearance was affected, by soaking time and particle size.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.1
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• pp.12-16
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• 2002

In this study, the physicochemical properties of warty black and glutinous rice flours were compared. Crude protein content of waxy black rice flour (9.01%) was higher than than of glutinous rice flour (7.54%). Most mineral contents of waxy black rice flour were higher than those of glutinous rice flour. The major fatty acids in the waxy black and glutinous rice flours were oleic acid (38.57% and 36.95%) and linoleic acid (38.60% and 39.10%). The major detected amino acids of both samples were aspartic acid, glutamic acid and arginine. Water binding capacity of waxy black rice flour (93.26%) was higher than that of glutinous rice flour (87.42%) . Swelling powers and solubilities of waxy black rice flour were lower than those of glutinous rice flour in according to increasing temperatures. Maximum absorbance wavelength (λ$_{max}$) and absorbance at 625 nm were similar between both samples. X-ray diffraction patterns of both samples showed traditional A type as Peaks 2$\theta$ at 15.1$^{\circ}$, 17.1$^{\circ}$, 18.0$^{\circ}$and 23.2$^{\circ}$. The relative crystallinities of waxy black and glutinous rice flours were 0.40 and 0.41, respectively.

• The Korean Journal of Food And Nutrition
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• v.30 no.1
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• pp.31-40
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• 2017

This study was undertaken to evaluate the quality characteristics and antioxidant characteristics of commercially available mixed grains in Korea. The quality characteristics of mixed grain products studied were the mixing ratio, water binding capacity, water solubility, swelling power, and pasting characteristics. The antioxidant characteristics assessed the total polyphenol, flavonoid contents, DPPH and ABTS radical scavenging activities. The mixing ratio of commercially available mixed grain products consisted of 5~25 kinds of grains, with maximum products containing 15-grain products. The water binding capacity, water solubility, and swelling power in commercially available mixed grain products were 99.83~122.83%, 6.91~39.26% and 7.76~86.92%, respectively. The peak, trough, breakdown, final and setback viscosity were $31.53{\pm}20.17RVU$, $25.24{\pm}13.22RVU$, $6.29{\pm}7.43RVU$, $50.27{\pm}25.84RVU$ and $18.74{\pm}8.68RVU$, respectively. Total polyphenol and flavonoid contents were $817.14{\sim}2,524.29{\mu}g\;GAE/g$ and $106.36{\sim}1,099.09{\mu}g\;CE/g$, respectively. The DPPH and ABTS radical scavenging activities were 31.91~151.70 mg TE/100 g and 28.09~119.92 mg TE/100 g, respectively. Products with high phenol content and radical scavenging activity were found to contain greater proportion of brown rice, colored rice, barley and soybean.