옴가열이 전분의 레올로지 특성에 미치는 영향

차윤환,Cha, Yun-Hwan 한국식품영양학회 2019 韓國食品營養學會誌 Vol.32 No.4

Ohmic heating is a heating method based on the principle when an electrical current passes through food. Since this method is internal, electrical current damage occurred during heating treatment. The results of ohmic heated starch's external structure, X-ray diffraction, DSC analysis and RVA were differed from those of conventional heating at the same temperature. Several starches changed more rigid by structure re-aggregation. This change in starch was caused by change of physical, chemical, rheological property. The rheology of ohmic heated potato and corn starch of different heated methods were compared with chemically modified starch. After gelatinization, sample starch suspension (2%, 3%) measured flow curves by rheometer. Cross-linked chemically modified starch's shear stress was decreased with degree of substitution reversibly. Ohmic heated more dramatic, at $60^{\circ}C$. Potato starch's shear stress was less than commercial high cross-linked modified starch. Flow curves of potato starches measured at $4^{\circ}C$, $10^{\circ}C$, $20^{\circ}C$. Showed that Ohmic heated potato starch's shear stress ranging between $4^{\circ}C$ and $20^{\circ}C$ was narrower than modified starch. According to this study, ohmic heated potato starch can be used by decreasing viscosity agent like cross-linked modified starch.

호화점 이하에서 옴가열이 감자 전분의 열적특성에 미치는 영향

차윤환,Cha, Yun-Hwan 한국식품영양학회 2012 韓國食品營養學會誌 Vol.25 No.4

Ohmic heating uses electric resistance heat which occurs equally and rapidly inside of food when electrical current is flown into. In other study, we researched about soybean protein's characteristic changes by ohmic heating. Nevertheless treated same temperature, denaturation of soybean protein were accelerated by ohmic heating than conventional heating. In this time, we studied thermal property change of potato starch by ohmic heating besides conventional heating. For this purpose, potato starch was heated at same subgelatinization temperature by ohmic and conventional heating. And thermal properties were tested using DSC. Annealing of starch is heat treatment method that heated at 3~4% below the gelatinization point. DSC analysis results of this study, the $T_o$, $T_p$, $T_c$ of potato starch levels were increased, whereas $T_c{\sim}T_o$ was narrowed. This thermal property changes appear similar to annealing's result. It is thought the results shown in this study, because the heating from below the gelatinization point. 6, 12, 24, 72, and 120 hours heating at $55^{\circ}C$ for potato starch, $T_o$, $T_p$, $T_c$ values continue to increased with heating time increase. The gelatinization temperature of raw potato starch was $65.9^{\circ}C$ and the treated starch by conventional heating at $55^{\circ}C$ for 120 hr was $72^{\circ}C$, ohmic was $76^{\circ}C$. The gelatinization range of conventional (72 hr) was $10^{\circ}C$, ohmic was $8^{\circ}C$. In case of 24 hours heating at 45, 50, 55, 60, $65^{\circ}C$ for potato starch, the result was similar to before. $T_o$, $T_p$, $T_c$ values continue to increased and gelatinization range narrowed with heating temperature increase. In case of conventional heating at $60^{\circ}C$, the results of gelatinization temperature and range were $70.1^{\circ}C$ and $9.1^{\circ}C$. And ohmic were $74.4^{\circ}C$ and $7.5^{\circ}C$. When viewed through the results of the above, the internal structure of starch heated by ohmic heating was found that the shift to a more stable form and to increase the homology of the starch internal structure.

옴가열이 전분의 열적 특성과 흡수력에 미치는 영향

차윤환,Cha, Yun-Hwan 한국식품영양학회 2014 韓國食品營養學會誌 Vol.27 No.1

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. Herein, we have studied thermal property changes of wheat, corn, potato and sweet potato starch by ohmic heating as well as conventional heating. And then we measure the water holding capacity of starches. Annealing of starch is a heat treatment method heated at 3~4% below the gelatinization point. This treatment changes the starch's thermal property. In the DSC analysis of this study, the $T_o$, $T_p$, $T_c$ of all starch levels have increased, and the $T_c$-$T_o$ narrowed. In the ohmic heating, the treatment sample is extensively changed but not with the conventional heating. From the ohmic treatment, increases from gelatinization temperature are potato ($8.3^{\circ}C$) > wheat ($5.3^{\circ}C$) > corn ($4.9^{\circ}C$) > sweet potato ($4.5^{\circ}C$), and gelatinization ranges are potato ($7.9^{\circ}C$), wheat ($7.5^{\circ}C$), corn ($6.1^{\circ}C$) and sweet potato ($6.8^{\circ}C$). In the case of conventional treatment, water holding capacity is not changed with increasing temperature but the ohmic heating is increased. Water holding capacity is related to the degree of gelatinization for starch. This result show that when treated with below gelatinization temperature, the starches are partly gelatined by ohmic treatment. When viewing the results of the above, ohmic treatment is enhanced by heating and generating electric currents to the starch structure.

옴가열이 전분의 외부와 내부 구조에 미치는 영향

차윤환,Cha, Yun-Hwan 한국식품영양학회 2015 韓國食品營養學會誌 Vol.28 No.1

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.

옴가열이 전분의 Pasting 특성에 미치는 영향

차윤환 ( Yun-hwan Cha ) 한국식품영양학회 2017 韓國食品營養學會誌 Vol.30 No.4

Ohmic heating is an internal heating method based on the principle that when an electrical current passes through food, electric resistance heat is uniformly generated internally by food resistance. Previous studies indicate that the thermal properties, external structure, internal structure, and swelling power of ohmic heat treated starch of various starches, such as potato, wheat, corn, and sweet potato, differed from those of conventional heating at the same temperature. In this study, the pasting property of starch, treated with ohmic and conventional heating, were measured by RVA (Rapid Visco-Analyzer). Our results show that as the ohmic heating temperature increased, the PV (Paste Viscosity) of the starch decreased significantly, and the PT (Pasting Temperature) increased. Changes in PV and PT indicate that the swelling of starch remains unchanged by ohm heating. The HPV (Hot Paste Viscosity), CPV (Cold Paste Viscosity) and SV (Setback Viscosity) of ohmic heated starch also differed from the conventional heated starch. The pasting property is similar to the viscosity curve of common cross-linked modified starch. In this experiment, we further confirm the similarity with modified starch and its usability.

옴 가열이 대두 단백질의 열변성에 미치는 영향

차윤환 ( Yun Hwan Cha ) 한국식품영양학회 2011 韓國食品營養學會誌 Vol.24 No.4

Ohmic heating uses electric resistance heat which occurs equally and rapidly inside food when an electrical current is passed throught. In this study, we observed the physical & chemical characteristics changes which occurs in soybean protein during heating denaturation by using ohmic and conventional heating. After the ohmic heating process, we could not find any change of the primary protein structure in the denaturated soy protein samples. However, the rate of imbibed water(RIW) of the ohmic samples was 2 times faster than that of the conventional samples. Also the ANS-surface hydrophobicity was decreased, which is very closely related to RIW. In the differential scanning calorimeter(DSC) analysis result, all 7S soyprotein fraction samples were completely denaturated by ohmic and conventional heating. However, the 11S samples were completely denatured only by ohmic heating. According to the DSC result, we decided that soyprotein was damaged by temperature and electrical current during ohmic heating. The damage of electrical current was a cause of the charcteristic changes.

FT-IR과 탄소동위원소 분석을 통한 연어유의 구분에 관한 연구

조은아,차윤환,이영상,Cho, Eun-Ah,Cha, Yun-Hwan,Lee, Young-Sang 한국식품영양학회 2012 韓國食品營養學會誌 Vol.25 No.4

This study analyzes the structure types of salmon oil to evaluate the purity of salmon oil products based on the 38 different types of imported salmon oil products distributed in the Republic of Korea. The major types of omega-3 foods in the salmon oil are ethyl ester (EE) and triglyceride (TG). If the salmon oil contained potential contaminants and was processed in order to remove it, EE type omega-3 fatty acids are found in concentration. This provides a good guide in assessing if products were made with EE type ingredients or re-esterified contaminated materials. The results of the FT-IR analysis showed significant difference in the C=O, C-O band positions in TG and EE. There were 19 TG type products and 19 EE type products. The analysis of carbon isotope ratio was performed on the types of TG and EE. There were different properties in the 19 TG type products. In one product, the carbon isotope ratio was -25.15 and the other 18 products showed -22.15~-23.96. The carbon isotope ratio of all 19 EE type products showed -21.91~-23.74. The results of the TLC analysis showed similar results with FR-IR. The re-esterified TG form was not detected in the TG type products, confirming that the TG type products contained natural salmon oil. This study aimed to provide the basic material in classifying the types of natural salmon oil and re-esterified salmon oil, by analyzing the pattern and proportion of FT-IR spectrum, carbon isotope ratio, and TLC.

명월초 추출물의 항산화성분 분리 및 루틴의 정량분석

전형주(Jeon, Hyeong-Ju),차윤환(Cha, Yun-Hwan),장혜륜(Jang, Hye-Rroon) 한국웰니스학회 2016 한국웰니스학회지 Vol.11 No.4

본 연구는 명월초 추출물의 항산화성분 분리 및 루틴의 정량분석을 평가하기 위한 것이다. 항산화성분의 함량을 가장 많이 함유한 명월초 잎 에탄올추출물(Leaf-E)에서 기능성 소재로서의 연구를 수행하였다. Flavonol 배당체의 분리 및 동정과 LDL-antioxidant 활성분석결과 80% MeOH 수용액을 여과, 감압 농축하여 MeOH 추출물을 얻었다. 이를 EtOAc 분획, n-BuOH 분획, H2O 분획으로 나누었으며, EtOAc 분획에 대해 silica gel column chromatography를 실시하여 4종의 Flavonol 배당체를 분리 및 정제하였다. 1H-NMR, 13C-NMR, DEPT spectrum 및 Mass spectrum 등을 통하여 화합물 1-Astrgalin, 화합물 2-Isoquercitin, 화합물 3-Kaempferol, 화합물 4-Rutin의 구조를 결정하였고, Rutin 함량 분석을 통해 명월초의 기능성 소재 및 융합소재로의 가능성을 평가하였다. This study is to evaluate the antioxidant activity and functionality of the Gynura Procumbens. The content of most commonly contains the content of the antioxidant patients early leaf ethanol was studied as a functional material in the extract (Leaf-E). Flavonol glycosides and Identification and separation of the LDL-antioxidant extracted by the activity analysis of 80% MeOH aqueous solution was filtered and concentrated under reduced pressure to obtain a MeOH extract. In EtOAc fraction, n-BuOH fraction, fractions were divided into H2O, the four kinds of Flavonol glycosides isolated and purified by silica gel column chromatography performed for the EtOAc fraction. 1H-NMR, 13C-NMR, DEPT spectrum and Mass spectrum, such as through the 1-Astrgalin compound, the compound 2-Isoquercitin, compound 3-kaempferol, to determine the structure of the compound 4-Rutin. Rutin substance containing a name beginning with a variety of activities that will be enough the value of a functional food material and fused material.

옥수수전분 현탁액의 알칼리 호화

조석철(Seok-Cheol Cho),신해헌(Hae-Hun Shin),차윤환(Yun-Hwan Cha),변유량(Yu-Ryang Pyun) 한국식품과학회 2007 한국식품과학회지 Vol.39 No.2

옥수수전분의 알칼리호화는 NaOH 첨가에 의하여 지수적으로 증가하였으며, 호화도가 급격히 증가하기 시작하는 구간을 알칼리호화 개시점으로 추정하였다. 10%(w/w) 옥수수 전분 현탁액의 40℃에서 호화개시점은 24.1 meq NaOH/g starch인 반면에 60℃에서는 9.8 meq NaOH/g starch이었다. 또한 옥수수전분 현탁액의 농도를 40%로 증가시킨 경우 40℃에서 9.5 meq NaOH/g starch에서 호화가 개시되었다. 이와 같은 결과로부터 전분의 알칼리호화 개시농도가 전분 현탁액의 농도와 온도에 반비례하는 것을 알 수 있었다. In this study, we examined the characteristics of alkali gelatinization of corn starch. Here, the degree of com starch gelatinization increased exponentially with the NaOH concentration of the starch slurry. The alkali gelatinization initiation point (AGIP) was obtained from the intersection point of gelatinization slope line, which resulted from the regression of the logarithmic degree of gelatinization, and was markedly changed. The effects of temperature and com starch concentration on alkali gelatinization were studied with a 10%(w/w) corn starch suspension. We found that this corn starch suspension gelatinized in 24.1 meq/g starch of NaOH at 40℃, and in 9.8 meq NaOH/g starch at 60℃. Moreover, a 40%(w/w) corn starch suspension gelatinized with 9.5 meq NaOH/g starch, even at 40℃. These results indicate that the amount of alkali added for the gelatinization of corn starch has an inverse relationship with the temperature and concentration of com starch.

위스키 종류 및 숙성기간에 따른 향미 성분 변화의 비교

이영상 ( Young Sang Lee ),조은아 ( Eun Ah Cho ),차윤환 ( Yun Hwan Cha ),윤도원 ( Do Won Yoon ),임덕호 ( Duck Ho Im ),최범구 ( Beom Gu Choi ),전주형 ( Joo Hyoung Jeon ) 한국식품영양학회 2011 韓國食品營養學會誌 Vol.24 No.3

This study analyzes flavor ingredients according to types of whisky and maturation periods based on total 40 different types of whisky that are mainly distributed to Korea via imports. Whisky was classified into four categories based on origin, and also into different categories based on maturity period, ingredients such as fusel alcohol, fatty acid, and fatty acid esters and proportion of patterns were analyzed. As a result of an analysis for fusel alcohol, high qualified types of alcohol including 3-methylbutanol, 2-methylbutanol, iso-butanol, and 1-propanol were detected from all Scotch whiskys, America whiskys, and Canadian whiskys. In particular, the proportional sum of 3-methylbutanol and 2-methylbutanol, and the sum of 3-methylbutanol and 2-methylbutanol/iso-butanol were regarded as core factors to determine each type of whisky. Acetaldehyde, ethyl acetate, and acetic acid increased as maturation and storage period became longer. As a result of the fatty acid and fatty acid ethyl ester analysis, the major fatty acids were dodecanoic acid and decanoic acid, both with detection of octanoic acid and hexanoic acid. However, dodecanoic acid, decanoic acid, and octanoic acid were lower than the detectable limit in American and Canadian whiskys, showing a unique phenomenon that hexanoic acid was detected only in very small amounts. Malt Scotch whisky showed higher significance than blended Scotch whisky, making it possible to classify types of whisky. Fatty acid ethyl ester contents showed significance with fatty acid either. In addition, changes in the whiskys based on maturation period were confirmed via proportions of fatty acids and fatty acid ethyl esters. In general, the proportion of fatty acids and fatty acid ethyl esters decreased as the storage period increased. This study provided basic data to classify types of whisky based on maturation periods by analyzing the proportion of flavor ingredients such as fusel alcohols, fatty acids, and fatty acid ethyl esters.