• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.757-761
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• 1995

The relationship between the molecular structure of rice starch and the texture of cooked rice was investigated using hot-water soluble rice starch. The structure of hot-water soluble starch bound amylose which was composed of small molecular weight and amylopectin which was composed of chain length of $\overline{DP}\;10{\sim}20$, and the average composition of amylose : amylopectin was 7 : 3. The molecular weight of amylose was the smaller and super long chain of amylopectin was the fewer, the extractable ratio of hot-water soluble rice starch was the higher. And hot-water solubility of rice starch be responsible for molecular structure of starch. On the texture of cooked rice, the extractable ratio of hot-water soluble rice starch was the higher, the hardness was the lower and the adhesiveness was the higher. The results suggest that the molecular structure of rice starch could be responsible for the texture of cooked rice.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.2
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• pp.219-222
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• 2005

Some structural characteristics of hot-water soluble and insoluble starches (waxy black rice starch) were investigated. The hot-water soluble material content of waxy black rice starch was higher (16.6%) than that (13.4%) of Shinsunchalbyeo starch heated at 98$^{\circ}C$ for 8 min. The Amax and absorbance at 625 nm for hot-water soluble and insoluble material of waxy black rice starch were lower than those of Shinsunchalbyeo. Elution patterns of hot water soluble and insoluble materials by gel permeation chromatography (Sepharose CL-2B) were similar in both samples.

• Korean journal of food and cookery science
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• v.16 no.5
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• pp.431-436
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• 2000

Gelatinization properties of potato starches which were prepared by steeping at 10 ${\pm}$ 1$^{\circ}C$ or 25 ${\pm}$ 1$^{\circ}C$ for 11 days were investigated. The pasting and initial gelatinization temperatures measured by rapid visco-analyzer (RVA) were increased, but the peak and trough viscosities of potato starch were decreased by steeping. The onset temperature, peak temperature, conclusion temperature, and enthalpy of gelatinization were increased by steeping as measured by DSC. The contents of hot-water-soluble carbohydrate and amylose in potato starch were decreased by steeping.

• Applied Biological Chemistry
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• v.39 no.3
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• pp.212-217
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• 1996

Molecular structural Properties of Potato starches from Irish cobbler(mealy Potato), Dejima(waxy or soggy potato) and Shepody were investigated. iodine reaction of Irish cobbler, Sephody and Dejima starches were 0.45, 0.44 and 0.43. ${\beta}-amylolysis$ limit of the starches was not different between the three potato types. The percentage of each fraction was different among samples : in general, Dejima starch had higher proportion of $F1(more\;than\;{\overline}{DP})$, $F2({\overline}{DP}40{\sim}50)$ and lower proportion of $F3({\overline}{DP}15{\sim}20)$ than those of Irish cobbler starch. When the starch was heated in excess water at $98^{\circ}C$ for 8min, the yield of hot water-soluble starch were higher in waxy type than in mealy one. Each potato variety showed different gel chromatography pattern of the hot water soluble starch. When the potato starches were hydrolyzed with 2.2N HCI at $37^{\circ}C$ for 48 hr, the molecular weight of the starch was decreased.

• Applied Biological Chemistry
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• v.49 no.3
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• pp.170-174
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• 2006

For the purpose of developing a high quality agricultural microbial inoculant, methods and materials for improving encapsulation were investigated. Preparation of capsule was conducted by improving extrusion system with micro-nozzle and peristaltic pump. The sodium alginate was selected because of its cheapness, stability of cells, and gel formation ability. The yields, physical properties and gel formation abilities of extractable alginate from sea tangle were investigated by hot water extractable and alkali soluble methods. The extraction yields of hot water extractable alginate (HWEA) and alkali soluble alginate (ASA) from sea tangle were 8 and 20%, respectively. The HWEA was almost not viscous even in 1.5% of the sample solution, whereas the ASA was very highly viscous in above 3% sample solution. The gel formation ability of each samples varied from 1.5% to 5% and the ASA showed a good gel formation ability at 3% solution as commercial alginate (CA). The soil microbial inoculant, Bacillus thuringiensis, Bacillus subtilis, Lactobacillus plantarum and Geotrichum candidum encapsulated sodium alginate with starch and zeolite for stabilizer. The survivability of encapsulated soil microbial inoculant using alginate without stabilizer appeared to be 66, 52, 70 and 50%, respectively. Inclusion of starch and zeolite with alginate bead increased viabilities in Bacillus sp. and Geotrichum candidum by 81-83% and 89%, respectively.

• Journal of the Korean Home Economics Association
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• v.39 no.1
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• pp.91-102
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• 2001

The non-starch polysaccharides in the cell wall of rice, glutinous rice, and black rice, were analyzed. They were fractionated into fractions; water-soluble, hot writer-soluble, ammonium oxalate-soluble, sodium hydroxide-soluble, potassium hydroxide-soluble, and the alkali-insoluble, according to the solvent solubility. The dietary fiber contents were 5.4% in glutinous rice, 4.2% in rice and 7.5% in black rice. The sodium hydroxide soluble fibers were abundant in each kind of rice, especially 4.01% in black rice. The water soluble fibers were 80% of dietary fiber in glutinous rice, 66% in rice, 86% in black rice. It was supposed that the content of the water soluble fibers in rice was increased by pounding. Pectic substances in water soluble fibers, hot water soluble fibers, and ammonium oxalate soluble fibers fraction, were 2.4% in glutinous rice fraction,1.59% in rice, and 1.12% in black rice. Alkali soluble fibers were considered as hemicellulose. Black rice contained 5.80% of hemicellulose, which was more than twice as much as glutinous rice(2.58%) and rice(2.22%). Alkali insoluble fibers were considered as cellulose, which showed no considerable difference. Among samples content of uronic acid in glutinous rice, rice and black rice were 0.9%, 0.66%, 1.8% respectively. Uronic acid of black rice was twice more than other samples tested. The fraction of black rice that uronic acid was extracted at most was the fraction of sodium hydroxide. Mono saccharides of the fraction was the glucose, the arabinose, the xylose.

• Korean Journal of Food Science and Technology
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• v.24 no.2
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• pp.187-192
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• 1992

Some structural characteristics of Japonica and Tongil type rice starches and their fractions were investigated to elucidate the differences between the two rice types. Japonica rice starches showed broader gelatinization temperature ranges and had higher ${\lambda}_{max}$ than those of Tongil ones. Intrinsic viscosity of starch, amylose and amylopectin for Japonica type were lower compared with those of Tongil type. ${\beta}-amylolysis$ limit of rice starch were not different between two rice types, but those of amy_lose and amylopectin of Japonica ty_p_e were lower than Tongil type. The average unit chain length(${\overline}CL$) and average outer chain length(${\overlne}OCL$) of Japonica type amylopectin were shorter than those of Tongil one. Sepharose CL-2B chromatography of hot water soluble starch revealed that each starch had unique elution profile.

• Korean Journal of Food Science and Technology
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• v.30 no.1
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• pp.97-102
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• 1998

Arrowroot starches, harvested in March, June, September and December, indicated that the December starch had the lower values of amylose content, ${\beta}-amylolysis$ limit and intrinsic viscosity, but the highest value of water-binding capacity. The swelling power were similar among different starches. The gelatinization by KSCN revealed that the December starch was the most resistant to alkali gelatinization. Gelatinization temperature, determined by differential scanning calorimetry, of the December sample was shifted to higher temperture by $1^{\circ}C$ compared with the others. When the December starch was heated at $98^{\circ}C$ for 8min, 93.8% of total amylose and 7.2% of total amylopectin were solubilized, which was the highest and the lowest, respectively.

• Food Engineering Progress
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• v.13 no.4
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• pp.360-364
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• 2009

The onion extractions of MIX treatment (5% $\beta$ cyclodextrin+1% calcium chloride+1% soluble starch mixture solution) using hot water (100${^{\circ}C}$ and 80${^{\circ}C}$) and ultrasonic treatment (25${^{\circ}C}$) incresed L values and decreased a and b values apart from the extraction methods. Extent of the browning reaction as caused by the MIX treatment (0.093) following 100${^{\circ}C}$ water extraction resulted in as low as 31% O.D. level, as compared to the control(0.296). Analysis of the pyruvic acid showed that the control had higher content of pyruric acid than MIX-treated samples. The MIX treatment had lower intensities and higher preferences of browning color and pungency taste compared to the control. The total and coliform microbial counts increased continuously during storage period, while the MIX treatment reduced the number of viable cells. Finally, it was concluded that the MIX treatment was highly effective in suppressing the undesirable browning color and pungent taste after processing, and the microbes increment during storage.

• Microbiology and Biotechnology Letters
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• v.21 no.2
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• pp.119-124
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• 1993

An alkalophilic microorganism for overproduction of cyclodextrin glucanotransferase (CGTase) was newly isolated from hot-water spring soil, and identified as Bacillus firmus var. alkalophilus H609. The strain maintained stability during preservation and cultivation for the enzyme production, and produced significant amount of CGTase corresponding to the volumetric activity of 75 units/mL at 37C, initial pH of 11.2, and after 40 hours. The strain excreted several different proteins showing CGTase activity that catalyzed the formation of mainly beta-and Gamma-type cyclodextrin (ratio of 7:1) from soluble starch without accumulation of alpha-type. Other enzymatic properties were also investigated.