• Applied Biological Chemistry
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• v.37 no.6
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• pp.463-471
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• 1994

Physicochemical properties, gelatinization and retrogradation characteristics of surfactant added sweet potato starches were investigated. Three different surfactants, SSL (sodium stearoyl-2-lactylate), Dimodan (mono/diglyceride) and SE1670 (sucrose fatty acid ester 1670) were used. Shapes and crystallinities of starch granules were not changed by the addition of surfactants. Total lipid contents increased and the amylose content decreased by the addition of surfactants and the order was as follows: SE1670>SSL>Dimodan. The swelling power and solubility at $80^{\circ}C$ decreased in the surfactant added starches. By amylograph, initial gelatinization temperature of untreated sweet potato starch was $72.5^{\circ}C$, and did not change by the addition of surfactants, but SE1670 or Dimodan added starch showed the peak viscosity. The peak temperature of gelatinization and enthalpy of untreated starch by DSC were $53.9^{\circ}C$ and 1.3cal/g, respectively. The peak temperature increased by the addition of surfactants, while the enthalpy decreased. In gelatinization by alkali, the viscosity was lower in surfactant added starches than in untreated starch at concentration. The degree of retrogradation by ${\alpha}-amylase-iodine$ method was a lower in SSL and SE1670 added starches than untreated starch and the enthalpy by DSC also decreased in surfactant added and retrograded starches.

• Applied Biological Chemistry
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• v.42 no.3
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• pp.240-245
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• 1999

The starches were isolated from normal (Mudeung) and waxy (Chalssal) hull-less barleys which contained similar contents of ${\beta}-glucan$ and amylose. Their water binding capacity, swelling power and solubility were analyzed. Scanning electron microscopy showed most starch granules had predominant lense shape granules. The particle size of starch granules was in the range of $0.1{\sim}30\;{\mu}m$. The higher pasting temperature was found for $Mudeung(84^{\circ}C)$ than for $Chalssal(61.5^{\circ}C)$. However, Mudeung barley had a lower peak viscosity(535 BU) than that of Chalssal(1,510 BU). Differential scanning calorymetry analysis showed that To and Tp for two starches were 57.0, $60.6^{\circ}C$ for Mudeung, and were 57.0 and $62.2^{\circ}C$ for Chalssal, respectively. Enthalpy changes were 7.9 and 13.2 J/g for Mudeung and Chalssal, respectively.

• Food Science and Preservation
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• v.18 no.2
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• pp.165-170
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• 2011

The physicochemical properties and cooking quality of Saechalssal bori (25% pearled ratio), which is a naked waxy barley, were investigated. The amylose, insoluble dietary fiber (IDF), soluble dietary fiber (SDF), total dietary fiber (TDF), and ${\beta}$-glucan contents of Saechalssal bori were 5.2, 10.8, 9.5, 20.3, and 3.7%, respectively. Pasting temperature, peak and final viscosity, and setback of Saechalssal bori were $66.5^{\circ}C$, 383.2, 231.3, and 55.6 RVU, respectively. The water absorption, expansibility, and soluble solid of Saechalssal bori were 232.2, 405.3, and 3.5%, respectively. As the ratio of water to grain increased, L value increased, whereas a and b values were decreased. The sensory evaluation showed that wateriness and overall acceptability increased with increasing ratio of water to grain, resulting in determining 2.1 times as the optimum ratio of water to grain. The cooked Saechalssal bori prepared using optimum condition had hardness (1.2 kg), cohesiveness (4.0), springiness (1.0), gumminess (5.1), chewiness (5.3), adhesiveness (0.2 kg), and A/H (0.8), respectively.

• Korean Journal of Food Science and Technology
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• v.25 no.6
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• pp.710-715
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• 1993

Physicochemical properties of defatted and lipid-reintroduced kidney bean, mung bean, and corn starches were investigated. Granule shapes of kidney bean and mung bean starches were oval/round, but corn starch was polygonal and each shape was not changed after defatting and lipid reintroducing. The granule sizes of starches ranged $12{\sim}45{\mu}m,\;10{\sim}32{\mu}m\;and\;5{\sim}20{\mu}m$ respectively, but those of lipid reintroduced starches increased slightly. All starches showed Ca type in x-ray diffraction but relative crystallinity was decreased by defatting. The amylose contents of starches increased after defatting but decreased after lipid-reintroduction. The swelling power and solubility of untreated starches at each temperature increased by defatting but decreased by lipid-reintroduction except corn starches. The initial pasting temperatures of kidney bean, mung bean and corn starches by amylograph were $87,\;67\;and\;80^{\circ}C$ respectively, and those of them were lowered by defatting. The peak viscosity, height at $50^{\circ}C$, consistency and setback on amylogram of starches decreased by defatting but increased by lipid-reintroduction.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.262-262
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• 2017

Brown rice contains a variety of nutritional and bio-functional components compared to milled rice. However, low consumer preference for steamed brown rice and short shelf life has been implicated as deterrents to the direct consumption of brown rice. This study was undertaken to determine the effect of degree of milling (DOM) on pasting and aging properties of brown rice cultivar. Short-grain (Japonica type) brown rice cv. Boseogchal (BSC), Baegjinju (BJJ), and Hiami (HIAM) were evaluated every month during 4 months storage. Rice cultivar were categorized into waxy (BSC), medium-waxy (BJJ), and non-waxy (HIAM) of which amylose contents were 6.81%, 10.06%, and 16.69~16.72%, respectively. Peak viscosity was the highest in BJJ followed by HIAM, and BSC, showing peak viscosity was lower at low temperature storage. At storage at room temperature from 60 to 120 days, the FFA content significantly increased in the rice samples with DOM1% followed by 3% and 5%, while not significant increase in DOM0% brown rice: at 120 days, the FFA ranged in 28.35~41.48, 111.99~130.06, 76.87~91.99, and 47.13~62.37 mg KOH/100g for DOM 0%, 1%, 3% and 5%, respectively. It indicated that the fat rancidity was the least in the order of DOM 0%, 5%, 3% and 1%. Storage at low temperature could reduce fat hydrolysis with lower FFA release, but rice grain with 1% MD also released more FFA compared to the other samples. It could be assumed that the most outer bran layer, approximately 1~3%, could provide a strong protection from fat rancidity. Pasting viscosity of rice samples also increased with increasing DOM rate. Results indicated that DOM was the most significant factor for lipid rancidity during storage, resulting in high FFA formation. It suggested that brown rice with DOM 0% and/or more than DOM 5% could provide the best shelf life.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.331-331
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• 2017

This study was conducted to know the influence of air temperature and sunshine duration on yield, chemical component, pigment color difference and starch characteristics of two colored rice cultivars in the plain area of Yeongnam province in Korea. The $L^*$, $a^*$, and $b^*$ value of brown rice in Hongjinju and Josaengheugchal rice cultivars was significantly different at continuous cultivated years, 2015 and 2016. The $L^*$, $b^*$ value of two colored rice was significantly increased in 2016 compared to 2015. The $a^*$ value of Josengheugchal rice cultivar was also significantly higher at 2016 than at 2015. It can be noticed the $a^*$, $b^*$, $L^*$ values in Josaengheugchal varied more than those in Hongjinju. Air temperature during ripening period in 2016 was higher than 2015, especially minimum temperature was too high to proper maturation for rice quality. In Josaengheugchal rice cultivar, sunshine duration after heading was longer in 2016 than in 2015. On the contrary, Hongjinju rice cultivar was ripened under condition of insufficient sunshine duration in 2016. The short growing duration by high temperature and long shiny duration made the lack of pigment for Josaengheugchal brown rice. In Hongjinju rice cultivar, shorten sunshine duration and higher night temperature were the source of the pigment deficiency. The grain size of rice which produced in 2016 was bigger than that of 2015 in both rice cultivars. The 1,000 grain weight of rice from 2016 was also bigger than that of 2015. Head rice ratio was high in the rice cultivars produced in 2015. Protein of milled rice in 2016 was more decreased than that of 2015 in Josaengheugchal rice cultivar, it showed reverse result in Hongjinju rice cultivar. Amylose contents of milled rice in 2016 were more decreased than that of 2015 in Hongjinju rice cultivar. Branch chain length distribution of amylopectin was shown a distinct difference between Josaengheugchal and Hongjinju rice flours by each produced year. Josaengheugchal rice cultivar produced in 2015 had a higher amount of short chains than that of 2016 rice starches. In Josaengheugchal rice cultivar, the pasting temperature and peak, trough, breakdown, final viscosity increased in rice flour which produced at 2016, whereas the setback viscosity and peak time showed lower value than those of rice from 2015. The most pasting properties (except of setback viscosity) of rice starch in Hongjinju rice cultivar grown in 2015 were higher than those of rice cultivar produced in 2016.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.3
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• pp.286-294
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• 1996

This experiment was conducted to determine the rice quality between slowlelease fertilizer(SRF) and conventional fertilizer (CF) with the amount of 100% and 80% under direct seeding on dry paddy field, respectively. In rice quality, the percentage of matured grain and immatured grain was higher in CF with machine transplanting than in SRF with direct seeding, and the less amount of fertilizer applied, the lower percentage of immatured grain was obtained. The percentage of carbohydrate showed the difference between CF and SRF, and higher at the level of 100% applicated than that of 80% application. The contents of fat and ash were higher in CF with less fertilizer, and there was no trend to different cultural methods but it was related to the amount of fertilizer in amylose content. The nitrogen and sodium content of milled rice was high in SRF under machine transplanting as well as direct seeding. Calcium and magnesium content showed high in direct seeding but there was not significantly difference between CF and SRF.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.546-551
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• 1993

Rice flour obtained by four different milling methods, Pin mill. Colloid mill, Micro mill, and Jet mill, were used to investigate physico-chemical properties and product. Crude fat, ash, and protein contents of rice flours between different milling methods were similar. Blue value, amylose content, and damaged starch which related to properties of rice flour were reduced in the order that of Jet mill, Micro mill, Colloid mill, and Pin mill. Water absorption index, water solubility index, and water retention capacity increased as damaged starch increased. Hardness of gel(15%) is the highest value for Pin mill. The finer granules (Jet mill) had lower gelatinization onset(To) and peak(Tp) than any other rice flours. Those result are simillar with amylogram properties. Enthalpy of gelatinization increased as damaged starch increased. Jet mill had the highest score (p<0.05) of overall test in sensory evaluation and good paste properties.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.612-618
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• 1999

Physicochemical properties of amaranth starch were compared with those of waxy rice and waxy corn starches. Amaranth starch granules vary from $1.1{\sim}1.9\;{\mu}m$ in diameter and are polygonal in shape. Total amylose contents from waxy rice, waxy corn and amaranth starches were 0.01, 0.03 and 0.07%, respectively. Swelling power of amaranth starch granule was slightly different from waxy rice. The swelling power of amaranth increased at $70^{\circ}C$. X-ray diffraction patterns of amaranth and other waxy cereal starches showed an A-type crystalline structure. Relative crystallinities of their starches were similar. According to pasting properties by Rapid Visco-Analyzer, amaranth starch showed a very high gelatinization temperature $(75.1^{\circ}C)$ and lower viscosity and higher stability than other waxy cereal starches during heating and cooling cycle. Peak onset temperatures (To) of starches from waxy rice, waxy corn and amaranth in DSC thermograms were $58.7{\sim}64.0$, 67.2 and $71.5^{\circ}C$, respectively, and their peak enthalpies were similar. Enthalpy of reheated amaranth starch after 3 day storage at $4^{\circ}C$ was higher than those of waxy corn and rices starchs.

• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.879-884
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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 solubility 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 viscosity 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.