• Applied Biological Chemistry
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• v.18 no.2
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• pp.102-108
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• 1975

Acorn starch preparation and some of its characteric study were made. The results obtained were as follows. 1) Yearly production of acorn in Korea is amounted to be 1,200,000 l approximately. The content of its carbohydrate was found to be 72.8%, so that this would be considered as one of good resources of starch in our country. 2) The major moieties of tannin constituents of acorn were found to be the gallic acid, catechin and chlorogenic acid. 3) The type of acorn starch granules were short oval shaped having the diameters of that were in the range of $3.5{\sim}5.2{\mu}$ and $8.0{\sim}19.5{\mu}$, respectively. 4) Initial gelatinifalion teniperaiure of acorn starch was $62{\sim}64^{\circ}C$, similar to those of corn and wheat starch. 5) Alnylose content of acorn starch were 27.1%, which is lower than that of barley but higher than that of potato starch. 6) The raising power of the acorn starch was 12.4, which is higher than that of the potato starch but lower than those of common cereal starches. 7) The blue value of acorn starch was 0.43, similar to that of wheat starch and higher than those of wheat potato and rice starch but lower than that of barley starch. 8) The alkali number of the acorn starch was 11.03, similar to that of corn starch but higher than those of barley and rice starch.

• Korean Journal of Food Science and Technology
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• v.49 no.5
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• pp.463-468
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• 2017

Waxy rice starch purified from Hwaseonchal white rice was modified by octenyl succinic anhydride (OSA) for use as an emulsifier. OSA-modified starches (1, 2, and 3% OSA, pH 8.5, 6 h) were investigated to understand their physicochemical and pasting properties, and emulsion stability. The degree of substitution (DS) of 1, 2, and 3% OSA starches was 0.0062, 0.0182, and 0.0214, respectively. FT-IR spectroscopy showed that OSA starches showed weak peaks at 1724 and $1572cm^{-1}$ and the peak at $3300cm^{-1}$ was reduced by an increase in the DS. Native and OSA starches showed A type crystallinity and a similar granular size. The OSA starch increased the peak viscosity, but decreased the onset and peak temperatures, and enthalpy with an increase in OSA concentration. The creaming index of emulsion of OSA starches decreased with an increase OSA concentration. It was suggested that the emulsion stabilizing capacity of OSA waxy rice starches increased with an increase in the OSA concentrations.

• Korean Journal of Food Science and Technology
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• v.8 no.3
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• pp.179-184
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• 1976

Properties of starch from three rice varieties in Korea, Indica types Tongil, Yusin and a Japonica type Jinheung were investigated. 1) Gelatinization temperatures of Tongil, Yushin and Jinheung rice were $72^{\circ}C,\;70^{\circ}C\;and\;68{\sim}69^{\circ}C$ respectively. Gelatinization temperature of Indica variety was higher than that of Japonica variety. 2) Blue values of Tongil, Yusin and Jinheung rice starch were 0.40, 0.39 and 0.35 respectively, in which differences among rice varieties were small. 3) Color intensity of three varieties of rice starch with iodine gave rise to absorption maxima at $610{\sim}625\;nm$. 4) Amylose contents of Tongil, Yusin and Jinheung rice starch were 23.2%, 21.3% and 20.6% respectively, which were lower than those of other cereals. Amylose content of Indica variety was higher than that of Japonica variety. 5) Alkali numbers of Tongil, Yusin and Jinheung rice starchs were 7.0, 7.0 and 6.8, respectively. The differences were negligible among rice varieties. Those values were higher than that of glutinous rice starch.

• Korean journal of food and cookery science
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• v.2 no.1
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• pp.45-53
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• 1986

This study was conducted to investigate the effects of the properties of sugar (20％, 30%) and starch (l5％, 20%, 25％) to Angdo on Angdo Pyun's preference, texture and color_ Textural characteristics were examined through sensory evaluation, Rheometer. Color test by Color and color difference meter. The properties through sensory evaluation were appearance, color, flavor, hardness, thickness and acceptability. With Rheometer, compression force, work ratio, adhesive work and gumminess were measured. With Color and Color difference meter, L, a ana b were measured. The results were as follows: 1. Sensory evaluation indicated that with the increase of starch addition, the Angdo Pyun maintained a worse apperance and got hardened and thickened. As the amount of suger increased, the Angdo fyun maintained better in color and flavor as well as its acceptability. 2. Rheometer measurement indicated that a compression force, work ratio, adhesive work and gumminess tended to increase, as the starch proportion increased. As the amount of sugar increased, the Angdo Pyun maintained a greater adhesive work, work ratio and gumminess. 3. Color and Color difference meter indicated that figure L ana a tended to increase and b, ΔE and ΔC decrease, as the starch proportion increased. 4. In the analysis of correlation between hardness and compression force, it was found that they are highly related. In view of the above results, it came to the conclusion that Angdo Pyun with the addition of 30％ sugar and 15％ starch could give the best result among the groups studied.

• Korean Journal of Food Science and Technology
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• v.18 no.6
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• pp.421-426
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• 1986

The carbohydrate characteristics and storability of two Korean traditional confections Seban-kangjeong (a Korean fried waxy-rice cookie) and starch-dashik (a Korean pressed starch cookie) were studied as compared with two Western confections fried cookie and biscuit. Seban-kangjeong showed lower contents of starch and sucrose and higher content of reducing sugar whereas starch-dashik showed higher contents of starch and sucrose and lower content of reducing sugar. Moisture content was higher in Korean confections than in Western confections. The degree of gelatinization was higher in Seban-kangjeong and fried cookie which were made through a frying process. Moisture adsorption isotherms were constructed for the four products. In storage test for 6 months under different temperature and humidity conditions, the relative humidity maintaining the initial moisture content of products was 68% for Seban-kangjeong and starch-dashik and 20% for fried cookie and biscuit. The ratio of retrogradation in storage was 15% in Seban-kangjeong, 20% in starchdashik and 28% in fried cookie and biscuit, showing the lowest progress in freezer storage.

• Korean Journal of Microbiology
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• v.27 no.3
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• pp.221-224
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• 1989

Amylolytic filamentous fungus, Aspergillus oryzae and nonamylolytic sugar fermentable yeast, Saccharomyces cerevisiae were fused by protoplast fusion in order to develope microorganisms having their intergrated function. Aminoacid auxotrophic properties were used as a genetic marker of protoplast fusion, and 35% PEG 4000 was used as a fusogenic agent. Complementation frequengy of fusion was $4.6\times 10^{-6}$ Obtained fusants showed the morphology of yeast strains, the amylase activity and the ethanol productivity. Among the properties of the fusants, morphology and prototrophic property were sustained stably but their ethanol productivity from starch was reduced. Although fusant strains had 0.5-fold ethanol productivity compared to that of S. cerevisiae in glucose medium, they produced ethanol from strach by direct fermentation.

• Journal of Life Science
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• v.17 no.9 s.89
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• pp.1260-1265
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• 2007

Magnetically separable enzyme-coated nanofibers were developed for the hydrolysis of starch. Stability of ${\alpha}-amylase-coated$ nanofiber was greatly improved and its residual activity was maintained over 92.7% after 32 days incubation at room temperature and under shaking conditions (200 rpm). The recovery of enzyme was high and enzyme activity after 10 recycle was 95.2% of its original activity. Developed enzyme-coated nanofibers were used for the hydrolysis of starch. When 0.5 mg of magnetically separable enzyme nanofibers was used, 40 g/l of starch (2 ml) was completely degraded within 40 min. The continuous enzyme reactor was developed and used for starch hydrolysis and 76% of starch (30 g/l) was hydrolyzed with 1 hr residence time.

• Korean Journal of Environment and Ecology
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• v.30 no.1
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• pp.92-97
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• 2016

The purpose of this study was to improve growth and survival rate of marine microalgae and macroalga zoospores using with eco-friendly capsulation materials. The capsulation materials were chosen an alginic acid which extracted from marine brown algae combining with starch and calcium chloride. The capsulated microalgae, Nannochloropsis salina and macroalga zoospores, Ulva australis were evaluated with growth and survival rate. When the mixed ratio of alginic acid was less than 50%, capsule formation was not performed. When the ratio of 50% alginic acid and 50% starch, the microalgae was shown the highest growth and survival rate increasing up to $8.74{\times}10^5cells\;mL^{-1}$ while 100% of alginic acid was the lowest rate up to $4.92{\times}10^5cells\;mL^{-1}$. The increasing starch ratio improved to their growth and survival rate, however decreasing alginic acid make physical capsule formation weaken. By applying on a surface of artificial reef, capsulated algal zoospores were germinated 99 individuals $cm^{-2}$. This attempt will be provided to basic core technology for marine afforestation in coastal area.

• Korean Journal of Food Science and Technology
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• v.48 no.4
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• pp.341-346
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• 2016

The AMY2B gene, encoding human pancreatic ${\alpha}$-amylase isozyme (HPA II), was expressed in Pichia pastoris, and the effects of chloride ions on HPA II activity toward starch substrates were investigated. As seen with chloride ion-dependent ${\alpha}$-amylases-including HPA I, the isozyme of HPA II-chloride ions increased enzyme activity and shifted the optimal pH to an alkaline pH. The activity enhancement by chloride was more significant at pH 8 than that at pH 6, suggesting that the protonation state of the general acid/base catalyst of HPA II was important for the hydrolysis of starches at an alkaline pH because of the increase in its $pK_a$ by chloride ions. The turnover values for cereal starches as the substrates markedly increased in the presence of chloride by up to 7.2-fold, whereas that for soluble starch increased by only 1.7-fold. Chloride inhibited substrate hydrolysis at high substrate concentrations, with $K_i$ values ranging from 6 to 15 mg/mL.

• Korean Journal of Food Science and Technology
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• v.52 no.4
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• pp.409-414
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• 2020

In this study, we conducted a physiochemical property analysis using commercial faba bean flour (CFBF), faba bean flour (FBF), and faba bean starch (FBS). We observed that the FBS granules were elliptical and cracked on the surface. Moreover, FBS showed significantly lower solubility and apparent viscosity than FBF and CFBF. With respect to the pasting properties, FBS exhibited a peak viscosity of 1349.3 cP at 94.8℃ and a breakdown of 42.7 cP, whereas FBF and CFBF displayed no pasting properties. The FBS gelatinization enthalpy (12.9 J/g) was relatively high compared with the values obtained for FBF and CFBF (5.9 and 4.6 J/g, respectively). The FBS X-ray diffraction patterns showed a C-type pattern with peaks at diffraction angle (2θ) of 5.9°, 15.2°, 17.3°, and 23.1°, which were the same in FBF and CFBF with relatively low peak intensity. These results represent basic data for using faba bean as a food material.