• Korean journal of food and cookery science
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• v.11 no.5
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• pp.472-478
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• 1995

녹두가루와 전분의 일반성분 및 무기성분을 조사하고 녹두가루의 농도(4-8%,건량기준), 녹두전분의 농도(3-8%,건량기준)에 따른 호화 특성 및 리올로지특성을 비교하였다. 녹두가루의 일반성분은 수분 6.8%, 단백질 25.0%,지방 1.21%,회분 1.77%,비타민 B$_1$과 B$_2$는 각각 0.57과 0.11 mg/100 g이었다. 전분의 비타민 함량은 B$_1$이 0.002 mg/100 g, B$_2$가 0.02 mg/100 g이었다. 가루의 무기질함량은 칼슘이 374.9 mg/100 g으로 가장 높았고 인(353.0 mg/100 g), 칼륨(176.3 mg/100 g), 마그네슘(116.9 mg/100 g), 나트륨(107.6 mg/100 g) 순서이었다. 전분현탁액의 광투과도로 부터 예측한 전분의 호화온도는 67$^{\circ}C$이었다 녹두가루와전분의 팽윤력은 60-8$0^{\circ}C$의 가열온도에서 직선적으로 증가하였으며 그 정도는 전분이 가루보다 컸다. 용해도는 $65^{\circ}C$이후부터 증가하여 녹두 가루는 8$0^{\circ}C$까지 지속적으로 증가하였으나 전분은 7$0^{\circ}C$ 이후에는 완만하게 증가하였다 녹두가루는 농도가 증가함에 따라 아밀로그래프의 최고 점도가 증가하였으나 전분은 6-8%의 농도에서 최고점도를 나타내지 않았으며92.5$^{\circ}C$에서 15분간 유지하는 동안 점도는 지속적으로 증가하였다. 최고점도의 대수값과 농도는 직선적인 관계를 나타냈으며 동일한 최고점도를 나타내는 농도는 전분이 가루보다 2.6ft'3도 낮았다. 녹두가루(4-8%, 건량기준)와 전분(3-8%, 건량기준)현탁액을 95$^{\circ}C$에서 40분간 유지시켜 호화시킨 액을 6$0^{\circ}C$에서 측정한 결과, 항복응력과 점조 도지수는 농도가 증가함에 따라 커졌고 유동지수값은 1.0보다 작아 녹두가 루와 전분호화액은 항복응력을 가진 의가소성 유체의 성질을 나타내었다 동일한 점조도지수값을 나타내는 농도는 전분이 가루보다 약 1.3%정도 낮았다.

• Korean journal of food and cookery science
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• v.32 no.5
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• pp.575-584
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• 2016

Purpose: Nurungji is a traditional Korean food made by yellowish scorched rice. After getting gelatinization of rice, a thin crust of scorched rice will usually be left in the bottom of the traditional cooking pot. In this study, physicochemical characteristics and antioxidant properties of five commercial nurungji products (CNP1, CNP2, CNP3, CNP4, and CNP5) were evaluated. Methods: Physicochemical properties of the five commercial nurungji products were evaluated with AOAC method. The antioxidant activities were assessed using the 1,1-diphenyl-2-picryl hydrazyl (DPPH), 2,2-azinobis-(3-ethyl-benozothia zoline-6-sulfonic acid)(ABTS), ferric reducing antioxidant power (FRAP), and reducing power assays. Results: Water content was the highest in CNP3, followed by CNP1, CNP2, CNP5, and CNP4. Crude ash content of all nurungji was less than 1%. In Hunter color parameter, the significantly highest a value (redness) and b value (yellowness) were measured in the CNP4 product, meanwhile the lowest in CNP3 (p<0.05). The nurungji products of CNP4 and CNP5 had the significantly higher content in total polyphenols and total flavonoids, compared to those of other products. CNP3 and CNP2 had the lowest in total polyphenols and total flavonoids, respectively. CNP4 and CNP5 products showed the significantly higher values in antioxidant activities, whereas CNP3 had the lowest activity. Conclusion: The high value of antioxidant activities in CNP4 and CNP5 might have been affected primarily by the total polyphenols with increasing browning color during the heat treatment.

• The Korean Journal of Food And Nutrition
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• v.28 no.1
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• pp.126-133
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• 2015

Ohmic heating uses electric resistance heat which occurs equally and rapidly inside food when the electrical current is transmitted into. Prior to the study, we have researched the potato starch's thermal property changes during ohmic heating. Comparing with conventional heating, the gelatinization temperature and the range of potato starch treated by ohmic heating are increased and narrowed respectively. This result is appeared equally at wheat, corn and sweet potato starch. At this study, we treated potato, wheat, corn and sweet potato starch by ohmic/conventional method and observed change of external structure by microscope and internal structure by X-ray diffractometer. Conventional heated at $55^{\circ}C$ potato starch was not external structural changes. But ohmic heated potato starch is showed largely change. Some small size starch particle were broken or small particles are made of larger particle together or small particles caught up in the large particle. Changes in ohmic heated potato starch at $60^{\circ}C$ was greater. The inner matter came to an external particle burst inside and only the husk has been observed. The same change was observed in the rest of the starch. The change of internal structure of potato starch was measured using X-ray diffraction patterns. There was no significant difference between ohmic and conventional heating at $55^{\circ}C$. But almost every peak has disappeared ohmic at $60^{\circ}C$. Especially $5.4^{\circ}$ peak to represent the type B was completely gone. When viewed from the above results, external changes with change in the internal crystal structure of the starch particles were largely unknown to appear. In conclusion, during ohmic heating changes of starch due to the electric field with a change in temperature by the heating was found to have progressed at the same time.

• Korean Journal of Food Science and Technology
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• v.24 no.4
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• pp.347-352
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• 1992

Physicochemical properties of native and defatted nonwaxy(Dongjin byeo) and waxy(Sinseunchalbyeo) rice starches were investigated. The granule shapes of rice starches were polygonal and X-ray diffraction patterns were A types, but relative crystallinity was decreased by defatting. The amylose content of defatted starches slightly increased, but water binding capacity of defatted starches decreased. Swelling power and solubility of starches increased with the increase of temperature, at each temperature increased by defatting. Transmittance of Dongjinbyeo and Sinseunchalbyeo starch suspensions showed a rapid increase at $60{\sim}65^{\circ}C$, $55{\sim}60^{\circ}C$ respectively. The initial pasting temperature by amylograph of Dongjinbyeo and Sinseunchalbyeo starches were $66^{\circ}C$ and $64^{\circ}C$, respectively. The gelatinization temperature of defatted starches was higher than that of the nondefatted starches. Dongjinbyeo starch decreased peak viscosity and breakdown by defatting, but Sinseunchalbyeo starch unchanged.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.3
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• pp.186-190
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• 2005

This experiment was conducted to collect the basic information on the varietal diversity in amylogram properties of 3 different rice sub-species under tropical conditions in IRRI 2001 wet season based upon correlation and principal component analysis. The peak viscosity and breakdown property of Tongil type, i.e.; temperate Indica species showed higher similarity with Japonica type species rather than typical Indica and tropical japonica types. The amylogram properties such as final viscosity, pasting consistency and setback of Tongil type varieties were lower than those of typical Indica and tropical japonica types. The peak viscosity showed positive correlation with trough, while the breakdown showed negative correlation with setback in all tested 3 rice subspecies. The first principal component was applicable to increase the gelatinization temperature, final viscosity, pasting consistency and setback, and applicable to decrease the peak viscosity and breakdown. Varietal classification by the principal component score of each pedigree could be applied to the interpretation of the community by the scatter diagram for the amylogram properties to the different sub-species of rice at IRRI conditions.

• Applied Biological Chemistry
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• v.40 no.4
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• pp.301-306
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• 1997

This study is presented to investigate the physico-chemical properties and qualities for the starch isogenic lines bred in barley(Hordeum vulgare L.).The pearling yield showed higher value in Franubet and Wafranubet than others, but the whiteness of pearled barley varied with the cultivars. The milling rate showed excellence in Franubet, fractured granular lines, whereas that of the waxy and round endosperm isogenic lines is poor. Franubet, the lines having fractures starch granule, was highest in starch content. The highest value in swelling power and water-binding capacity of the barley was proved by the lines having waxy and fractured starch endosperms. The amylogram patterns indicated that the waxy lines such as Wanubet and Wafranubet have lower initial gelatinization temperature and higher maximum viscosity than those of the normal lines. ${\beta}-Glucan\;viscosity$ was generally higher in waxy barley but changed greatly with the cultivars. The water absorption, soluble solid and expansibility in cooking property showed the highest value in waxy and fractured starch granular lines, and the whiteness of cooked barley did not differ with cultivars.

• 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 Science and Technology
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• v.45 no.6
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• pp.747-753
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• 2013

The physicochemical properties of sweet potato (SP) starches reclaimed from an SP-processing sludge without freezing (RC/NF) and with freezing (RC/FR) were investigated. Lab-isolated (LI) SP starch, as a control, were prepared from raw SP. RC/NF and RC/FR SP starches were recovered from SP-processing sludges by the repeated sieving and washing procedure. The total starch contents and amylopectin branch-chain distributions did not differ for three SP starches. Relative to LI and RC/NF SP starches (possessing similar physicochemical characteristics), the apparent amylose and phosphorus contents, swelling factor, and pasting viscosity were reduced for RC/FR SP starch. However, the freezing treatment altered X-ray diffraction pattern (at $5.5^{\circ}$, $11-12^{\circ}$, and $24^{\circ}$ $2{\theta}$) of RC/FR SP starch, which likely increased its gelatinization peak and completion temperatures. Its amorphous region in total diffractogram was reduced, resulting in the enhanced relative crystallinity. Overall results suggested SP starches recovered from an SP-processing sludge would have the potential to replace commercial SP starch products.

• Korean Journal of Food Science and Technology
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• v.40 no.3
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• pp.321-325
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• 2008

This study was carried out to examine the effects of wheat flour ferment cultured by Lactobacillus acidophilus on the physical characteristics of cooked noodle. Different scanning calorimeter(DSC) analysis results for noodle gelatinization showed that the noodles containing flour ferment had higher enthalphy values than the control noodle. And based on the degree of retrogradation for the noodles containing the flour ferment, enthalpy decreased as the amount of the ferment increased, resulting in the delay effect on the retrogradation. According to textural property evaluations over a storage period, the noodles containing the flour ferment had increases in hardness and cohesiveness, and the springiness of the control group was higher than that of the noodles containing the flour ferment; however, this difference between groups gradually disappeared with increasing storage time. Finally, the noodles containing 10% flour ferment had a higher overall preference score than the control group, indicating that the addition of the flour ferment during noodle production can have a beneficial effect on the preference.

• Food Science and Biotechnology
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• v.16 no.6
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• pp.943-947
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• 2007

The acid modification of waxy rice starch was conducted to improve the yugwa production process. The intrinsic viscosity, paste viscosity, and differential scanning calorimetry characteristics of acid modified starch were measured, and bandaegi and yugwa prepared from acid modified starch were evaluated. The intrinsic viscosities of acid thinned starches were 1.48, 1.27, 1.15, and 0.91 mL/g after reaction times of 1, 2, 3, and 4 hr, respectively. The gelatinization enthalpy was reduced from 16.3 J/g in native starch to 15.8, 15.3, 14.7, and 14.5 J/g in acid thinned starches as the time of acid thinning increased. The peak viscosity and final viscosity decreased with increasing the time of acid thinning, but the pasting temperature was slightly increased in acid thinned starches. The hardness of bandaegi from acid thinned starches under high pressure greatly decreased relative to the control, typical yugwa. Yugwa from acid thinned starch under high pressure maintained a homogeneous structure containing tiny and uniform cells similar to that of native waxy rice starch used for typical yugwa. Acid thinning under high pressure appears to be a good alternative to the existing steeping process for better yugwa quality.