• Journal of the East Asian Society of Dietary Life
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• v.10 no.5
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• pp.431-438
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• 2000

The physical and processing properties of acorn jelly were investigated to see the effect of polysaccharides in seaweed extract and corn starch. The yield of acorn jelly added starch concentration was slightly increased when the concentration was added more. However, moisture content and color had no significant changes with concentration. In the case of acorn jelly added sea tangle, color of acorn jelly was darker, but color of the jelly with carrageenan was lighter. According to the concentration of seaweed extract, the hardness was increased as concentration was added. The texture of acorn Jelly added agar had the highest binding. In the case of acorn jelly added corn starch, there were no significant changes, but this binding was stronger than the acorn jelly added extract of marine algae. In the physical and sensory properties of acorn jelly with corn starch, the ideal mixture ratio between the acorn jelly and the corn starch was 6:4.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.803-810
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• 1998

The mechanical and thermal properties of solutions of acorn starch were investigated, to determine the effect of sucrose on the retrogradation. The contents of moisture and amylose of purified acorn starch was 9.35, 27% respectively. From the moecular weight distribution, Mw and Mn of acorn starch were 1,220,432 and 137,201 relatively and the polydispersity of acorn starch was 8.8952. The creep compliance of acorn starch with and without sucrose were decreased with increasing sucrose concentration in the short term. The temperatures of DSC curve of 15% acorn starch solution containg sucrose shifted slightly to higher temperatures with increasing sucrose content. The enthalpy change associated with the gelatinization was increased with increasing sucrose content. After 7 days storage, the creep compliance of acorn starch gel with sucrose were shown higher than acorn starch gel. Regelatinization enthalpy of acorn starch/sucrose/water system was decreased with increasing sucrose content and increased with storage time. In addition, the characteristic temperatures such as onset temperature, peak temperature and conclusion temperature was increased by sucrose addition. Retrogradation ratio decreased with increasing sucrose content, thus sucrose inhibit retrogradation in the long term. Sucrose acts as an antistaling reagents and retatards the retrogradation.

• Korean Journal of Food Science and Technology
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• v.21 no.1
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• pp.9-12
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• 1989

Sensory characteristics of acorn gels were evaluated as affected by acorn starch concentrations(7, 8, 9, 10 and 11%) and by soaking periods(4, 8 and 16 days) of acorn and acorn flour. The characteristics evaluated were color, clarity, firmness, cohesiveness, flavor and astringency. Panelists indicated in the scoring test that all the characteristics were pronounced as the starch concentration increased, except clarity, The result of ranking test on gels made with acorn starch soaked for 4, 8 or 16 days indicated that color, firmness, cohesiveness, flavor and astringency decreased, as soaking period increased. However, the soaking periods did not affect clarity of acorn gels.

• Korean journal of food and cookery science
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• v.8 no.1
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• pp.9-14
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• 1992

The morphological properties of acorn starch granules and starch gels were examined with scanning electron microscope and X-ray diffractometer. The shape of acorn starch granule was rounded triangular and some elliptical. The size distribution of starch granule was also analyzed. The mean value of minor axis, major axis and the ratio of those were 4.785 $\mu\textrm{m}$, 7.30 $\mu\textrm{m}$ and 0.68, respectively. The surface micro-structure of acorn starch gels were investigated by SEM. Acorn crude and refined starch gel were very different in surface micro-structure. X-ray diffraction pattern of acorn starch was C-type, and the pattern of acorn starch gels were extremely different because of disintegration of starch granules by gelatinization. The diffraction intensity of acorn refined starch gel was slightly higher than crude starch gel.

• Korean journal of food and cookery science
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• v.11 no.2
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• pp.158-163
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• 1995

This study was surveyed and compiled the contribution about acorn in korea .the physico-chemical properties of acorn and acorn starch. preparation of acorn starch and elimination of the acorn tannin, the rheological properties of acorn starch gel. Nutrition of acorn and antioxidative activity of tannin in acorn extract. The result obtained were as follow. 1. The chemical compositions of acorn were water 6.5∼13.7%, crude ash 1.9∼3.4%, crude fat 1.1∼5.0%, crude protein 5.8∼7.8%, crude fiber 2.1∼3.6%, N-free extract 71∼77.5%, total tannin 4.6∼9.3%, Ca 92.7∼460.9mg%, p 80.0∼740.9mg%, Na 66.2∼93.9 mg%, and K 867.9∼983.1mg%. 2. The acorn tannin was extracted with water, acetone, and ethanol. The generation method was wash SE settling method with water. 3. The shape of acorn starch granule was rounded triangular and some elliptical, rasing power 12.4∼12.5, Blue value 0.43∼0.47, Alkali number 10.8∼11.3, Amount of Arnylose 28.8∼30.50% Tannin contents on the initial go tim-zation temperature of acorn starch were not influenced but maximum and cooling viscosity o the acorn starch were decreased. 4. Nutritional effect and diet absorption rate were not influence, by rice and 20% T-A(elimination of tannin from the acorn) mixed diet, and the content of lipid in s rum were not influenced by rice 40% and T-A (elimination of tannin from the acorn) mixed diet. 5. jallic acid, digallic acid, gallotannin were contained in acorn powder extract. The main antioxidative : stlvity was speculated due to the gallic acid.

• Journal of the Korean Home Economics Association
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• v.23 no.1
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• pp.33-47
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• 1985

The rheological properties of acorn starch gel were investigated in region of small and large deformation. The properties were compared with those of potato and wheat starch gel. On the physical characteristics and the effect of tannin contents of acorn starch were examined. RESULTS : 1. X-ray diffractogram of acorn starch showed C-type and its granules swelled gradully with heating. 2. Hardness, brittleness and both small and large deformation of the acorn starch gel were remarkably large, also the concentration dependence of the acorn starch gel could be recognized in small deformation and hardness. 3. The Young's modulus of Hookean body in small deformation and the rupture stress in large deformation differed obviously from the parameters of rheological properties in various gels. 4. It was found that the selling power, viscosity and rhelogical properties were affected obviously by the tannin.

• 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.

• Food Science and Preservation
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• v.11 no.4
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• pp.496-502
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• 2004

Purified acorn starch was obtained from alkali precipitation method. Acorn amylose and acorn amylopectin were fractionated from purified acorn starch by butanol improvement method. Gel permeation chromatography (GPC) was used to measure molecular weight distribution of acorn starch, acorn amylose, acorn amylopectin and corn starch, corn amylose, corn amylopectin. GPC measurement diagrams were obtained by each retention time. And then, we used DMSO and DMF as solvent, pullulan as standard material. We calculated the Number-average molar mass (Mn), Weight-average molar mass (Mw) and polydispersity from molecular weight distribution of each sample. As a result of estimating molecular weight using GPC, Mw of amylose has small value than Mw of amylopectin. From this fact, the molecular structural aspects of amylose and amylopectin were predicted and it was in good agrement with the tendency of polydispersity by GPC. The polydispersity of starch had big value than amylose and amylopectin, from this result, it might be known that the range of molecular weight appeared broad by heterogeneous properties of two components. The viscosity of purified acorn starch, amylose, amylopectin seperated from acorn starch, was decreased by increasing the shear rate and raising the temperature exponentially. Acorn starch solutions exhibited pseudoplastic power law fluid behavior.

• The Korean Journal of Rheology
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• v.10 no.1
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• pp.7-13
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• 1998

중량 평균 분자량이 1.22$\times$106이고 다분산도가 8.90이며 수분과 아밀로오스 함량이 각각 9.35%, 27%인 도토리 전분에 sucrose를 첨가하여 동적 유변학적 특성에 대한 온도와 농도의존성을 고찰하였다. AS(acorn starch)-sucrose 계의 점도는 전단속도가 증가하면 감 소하는 전단담화 현상을 나타내며 sucrose 농도가 증가할수록 점도가 증가하였고, Casson 식에 의해 얻어진 항복치는 sucrose 농도가 증가하면 증가하였다. 저장영률과 손실영률은 sucrose 농도가 증가하면 단일하게 증가하였고 손실 탄성률은 온도가 증가하면 감소하였다. DSC 측정자료를 zipper model에 적용시켜 본 결과 sucrose 농도가 증가할수록 zipper의 수 와 junc-tion zone의 수는 증가했으며 크기는 감소하였다. Sucrose는 전분과 수소결합을 형 성하여 용액내에서 가소제처럼 거동함을 알수있었다.

• Korean journal of food and cookery science
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• v.3 no.1
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• pp.14-19
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• 1987

The physicochemical properties of acorn starch were investigated by comparing acorn crude starch and refined starch, Proximate composition analysis revealed that the contents of crude protein, fat and ash were higher in acorn crude starch than in refined starch. Water binding capacity and swelling power of crude starch were a little higher than refined starch. Gelatinization temperature determined by optical transmittance and by Amylograph were $68^{\circ}C$ and $73^{\circ}C$, respectively. The viscosity of crude starch had the amylose content of 28.8%, and the molecular weight of amylose was 20, 425 and glucose unit per segment of amylopectin was 21.