• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.5
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• pp.792-799
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• 2013

This study was designed to develop natural browning inhibitors. The anti-browning effects of distilled water (SBD) and 80% ethanol extracts (SBE) of Scutellaria baicalensis Georgi in apple slices were investigated by L and ${\Delta}E$ values. Both SBD and SBE were effective in reducing the browning of apple slices and were successively fractionated into chloroform ($CHCl_3$), ethyl acetate (EtOAc), and water ($H_2O$) fractions. These extracts were measured for total phenolic content, flavonoid content, anti-oxidative activity (through free radical scavenging activity and the FRAP assay), ferrous ion chelation, and the inhibition of PPO (polyphenol oxidase) activity. Overall, fractions of SBE were better than fractions of SBD in all measurements. The highest total phenolic and flavonoid content were measured in the EtOAc and $CHCl_3$ fractions of SBE. EtOAc and $CHCl_3$ fractions also exhibited the highest anti-oxidative activities (in DPPH and ABTS free radical scavenging and the FRAP assay). Unusually, the highest ferrous ion chelating capacity was found in the $H_2O$ fraction of SBD, but the other fractions showed more than triple the ascorbic acid already in use. Also, $CHCl_3$ fractions showed a stronger inhibition of PPO activity than ascorbic acid. All of these results suggest that EtOAc and $CHCl_3$ fractions from Scutellaria baicalensis can be used as natural anti-browning agents.

• Restorative Dentistry and Endodontics
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• v.28 no.5
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• pp.402-408
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• 2003

This study was done to present a criterion in selection of the most proper light sources and materials by measuring metamerism index(MI) of the light curing composite resins with spectrocolorimeter. Metamerism is defined when two objects appear to be the same color in one illuminant but different in another. This is due to the fact that they have different spectral curves that fail to match under the second illuminant. In this study, A1 & A3 shade of five light curing composite resins (Esthet-X, Filteck Z250, Filteck A110. Charisma. Vitalescence) were chosen based on Vita shade. Five samples were made for shade of each product with Teflon mold (diameter: 15mm, thickness: 2mm). Metamerism index of each samples on a Barium sulfate plate($L^{*}=96.54,{\;}a^{*}=0.19,{\;}b^{*}=0.01$) prepared for sample fixation were measured with spectrocolorimeter(Miniscan XE plus. Model 4000s. Hunter Lab. USA) by applying standard light source D^{65}, C. Fcw, TL84 and A. Standardization was done with reference standard(X=80.8, Y=85.7, Z=90.8) and light trap. The results were as follows. 1. Different resins with same Vita shade showed recognizable color difference (${\delta}E^{*}>2$). 2. All composites had MI below accepted value 0.5 between standard illuminant(D$_{65}$, C, & A) and below 1.5 under fluorescent condition (Fcw & TL84). 3. MI value between $D^{65}$ and A showed higher value than MI value between other source of light(p<0.01). 4. All resins except Z250 showed MI value that A3 is higher than A1 between $D^{65}$ and A(p<0.05).except Z250 showed MI value that A3 is higher than A1 between $D^{65}$ and A(p<0.05).

• Applied Biological Chemistry
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• v.39 no.5
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• pp.384-388
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• 1996

This research was conducted to investigate the effective methods for browning inhibition on yam (Dioscorea aimadeimo) during dehydration by physical and chemical pretreatments. Moisture, crude protein, crude fiber and N-free extract contents of yam were 81.17%, 1.43%, 0.29% and 15.81%, respectively. Yams were sliced to 0.5 cm thickness and placed to single and poly layer in plastic tray, and then changes of their weights were measured during air dehydration at $50^{\circ}C,\;65^{\circ}C,\;and\;80^{\circ}C$. The dehydration time reaching to optimum moisture level for the pulverization of the yam slices were 10, 6, 3 hours(single layered) and 12, 7, 5 hours(multi layered) at the respective temperature. To inhibit browning at $80^{\circ}C$ air dehydration, water and steam blanching, microwave treatment effects were investigated on yam slices for 30 sec. and 60 sec. Steam blanching for 30 sec. was comparatively effective to inhibit browning of yam slices. Yam slices were immersed in single and combined browning inhibitor solutions and evaluated for browing degree during dehydration by the values of Hunter L, a, b and ${\Delta}E$. The most effective pretreatment to inhibit browning of yam slices was immersion In the solution containing 500 ppm of citric acid and 1000 ppm of cysteine for 1 min.

• Biomolecules & Therapeutics
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• v.6 no.2
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• pp.219-224
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• 1998

The bioequivalence of two clarithromvcin products was evaluated with 16 normal male volunteers (age 23-28 yr, body weight 57.5-75.517g) following single oral dose. Test product was ReYon Clarithromycin tablets (ReYon Pharm. Corp., Korea) and reference product was Klarici $d_{R}$ tablets (Abbott Korea). Both products contain 250 mg of clarithromucin. One tablet of the test or the reference product was administered to the volunteers, respectively, by randomized two period cross-over study (2$\times$2 Latin square method). The determination of clarithromycin was accomplished using a modified agar well diffusion bioassay. As a result of the assay validation, the quantification of clarithromycin in human serum by this technique was possible down to 0.03$\mu$g/ml using 100$\mu$l of serum. The coefficient of variation (C.V.) was less than 10%. Average drug concentrations at each sampling time and pharmacokinetic parameters calculated were not significantly different between two products P>0.05); the area under the curve to last sampling time (24 hr) (AU $Co_{24hr}$ (8.10$\pm$ 1.26 vs 8.22$\pm$ 1.627g . hr/ml), AUC from time zero to infinite (AU $Co_{\infty}$) (8.61 $\pm$ 1.28 vs 8.84$\pm$ 1.71 $\mu$g . hr/ml), maximum plasma concentration ( $C_{msx}$) (0.87$\pm$0.22 vs 0.88$\pm$0.19 $\mu$g/ml) and time to maximum plasma concentration ( $T_{max}$) (2.69 $\pm$0.48 vs 2.56$\pm$ 0.51 hr). The differences of mean AU $Co_{24h}$, $C_{msx}$ and $T_{msx}$ between the two products (1.44, 1.39, and 4.65%, respectively) were less than 20%. The power (1-$\beta$) and treatment difference ($\Delta$) for AU $Co_{24hr}$, and $C_{max}$ were more than 0.8 and less than 0.2, respectivly. Although the power for $T_{max}$ was under 0.8, $T_{max}$. of the two products was not significantly different each other (p>0.05). These results suggest that the bioavailability of ReYon Clarithromycin tablets is not significantly different from that of Klarici $d_{R}$ tablets. Therefore, two products are bioequivalent based on the current results. results.sults.sults.s.s.s.s.s.s.s.

• Journal of agriculture & life science
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• v.45 no.4
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• pp.121-133
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• 2011

Effects of roasting on vitamin E content, color, microstructure and moisture of peanuts, and vitamin E content in peanut oils prepared from the roasted peanuts were investigated. Runner-type peanuts were roasted at 140, 150, and $160^{\circ}C$ for 10-20 min. As roasting temperature and time increased, the CIELAB $L^*$ value of peanuts decreased while $a^*$ and $b^*$ values increased, resulting in formation of the golden brown color of roasted peanuts. Moisture ratio (M/Mo) and color $b^*$ value of peanuts roasted at 140 to $160^{\circ}C$ showed a correlation of $b^*=21.61\;(M/Mo)^2-40.62\;(M/Mo)+34.12$ ($R^2=0.9123$). Overall changes in the tocopherol contents of peanuts and peanut oils were significantly affected by roasting temperature and time (p<0.05). Roasting at $140^{\circ}C$ caused a slight increase in the levels of tocopherols of peanuts over roasting time up to 20 min (p<0.05). There was no significant change in the tocopherol levels of peanuts during roasting at $150^{\circ}C$ for 20 min (p>0.05). At $160^{\circ}C$, the levels of tocopherols significantly decreased during the initial 10 min of roasting (p<0.05) while there was no extended loss after 10 min, resulting in about 5, 12, 20, and 10% losses of ${\alpha}$-, ${\beta}$-, ${\gamma}$- and ${\delta}$-T, respectively. After 20 min, total tocopherols decreased by 18%. However, tocopherol contents of pressed peanut oils significantly decreased at all roasting temperatures (p<0.05). After roasting peanuts at $160^{\circ}C$ for 20 min, about 84% of initial ${\alpha}$-T in peanut oils was retained. ${\alpha}$-T was the most stable to roasting while ${\gamma}$-T was the least. Swollen epidermal cells on the inner surface and broken cell walls of parenchyma tissue of peanut cotyledon were observed in peanuts after roasting at $160^{\circ}C$ for 15 min. Severe changes in microstructure of peanut by roasting would contribute to vitamin E stability because of exposure of oil droplets in peanuts to oxygen.

• Korean Journal of Food Science and Technology
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• v.53 no.5
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• pp.657-668
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• 2021

We prepared the growth and survival models of enterohemorrhagic Escherichia coli (EHEC) and Campylobacter jejuni in milk as a function of temperature and assessed the microbiological risks associated with the consumption of whole milk. EHEC and C. jejuni were not detected in whole milk (n=195) in the retail market. The minimum growth temperature of EHEC in milk was 7℃. The lag time of EHEC in whole milk was longer than that in skim milk. The survival ability of C. jejuni in milk was better at 4℃ than at 10℃. Lower delta values were observed in whole milk than in skim milk, indicating that C. jejuni survived better in skim milk. The probability of foodborne illness from whole milk consumption was 5.70×10^-5 for EHEC and 9.86×10^-9 for C. jejuni. Sensitivity analysis results show that the market temperature of EHEC and the dose-response model of C. jejuni are correlated with the probability of foodborne illness.

• Food Engineering Progress
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• v.14 no.2
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• pp.135-145
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• 2010

In order to enhance overall quality of the Backsulki, a sweet potato flour (SPF) which is rich in sugar and dietary fiber was added into the rice flour at 0, 5, 15, and 25% (w/w, db) ratios. Quality changes of the products were evaluated by storing at 5, 15, and 25$^{\circ}C$ for 4 days. Water binding capacity, swelling power, and solubility of the products increased as the SPF increased. Hunter colorimetric a- and b-value increased while L value of the products decreased as the SPF increased. Retarded retrogradation of the flour mixtures containing the SPF was shown from the DSC thermogram as indicated by the decreased $\Delta$H values. Increases in $T_{i}$ and $T_{p}$ values in relation with the starch gelatinization were shown from the DSC thermogram with a temperature margin of 15-20$^{\circ}C$ as the SPF increased. Increases in softness along with decreases in springiness and chewiness of the products were shown as the SPF increased. It was not so much the storage temperature as the added SPF affected the final texture of the products. Retarded growth of the total microbes of the products was noted by the added SPF during storage at 25$^{\circ}C$ for 3 days. Regarding the above and additional sensory preference scores of the products, a 15%(w/w) level of the SPF was suggested as optimum for the best Backsulki with improved qualities.

• 전기의세계
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• v.27 no.5
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• pp.33-54
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• 1978

(차례) 1.산학협동심포지업 (1)우리나라에서의 연구개발과 산학협동 (2)산학협동과 산업계의 역할 (3)산학협동의 현황과 진로 2.학술회의A (1)전력게통의 계층구조와 협조원리에 관한 연구 (2)2중층괴상회전자 유도전동기의 이론해석 (3)초고주파가열장치에 사용하는 철공진변압기의 해석적 설계 (4)한국전기기시험연구소 대전력단락 시험설비설계 (5)직류전동기제어를 위한 Thyristor Chopper정류회로에 관한 연구 (6)선로의 개폐정보를 포함하는 전력계통의 상태추정 (7)단일신경세포에 대한 ITEM 신호 특성 3.학술회의B (1)MMM-1 Computer System의 설계 및 제작 (2)Adaptive Delta Modulation System의 성능비교 연구 (3)6GHZ FMD마이크로파 무선전송장치의 개발 (4)적선도에 의한 회로망함수의 결정 (5)동맥혈압의 해석과 그의 전기적 유사모델 (6)피부감각의 정보전달 특성에 관하여 (7)선형직접회로의 공정설계 및 그 특성 조성 (8)DH L.D의 전기적포화현상에 관한 이론적 해석 (9)Potocoupler를 이용한 Isolator 4.학술회의C (1)Al-Al$_{2}$O$_{3}$ -Al박막구조의 전기적 특성 (2)이종금속에 샌드위치된 고분자물질의 단락전조 (3)유전체가 일부체워진 직 6면체의 캐비티의 다중모오드 해석 (4)반도체 가스 검지소자의 제조 및 그의 전기적 특성 (5)실리콘 산화공정에 대한 실험적 고찰 (6)진공증착법에 의한 InSb 박막제도에서 열처리효과 (7)(Ba$_{1}$-xBix) Tio$_{3}$ PTC thermistor의 첨가량의 최적건안 (8)금속박막증착시 두께조절 5.특별강연회 (1)일본에 있어서의 절력계통공학연구 (2)Linear Motor의 최근개발동향량도 높았다. valine과 leucine 및 aspartic acid, glycine과 glutamic acid, leucine과 aspartic acid 간에는 고도의 정상관, glycine과 serine, valine과 phenylalanine, threonine과 proline, phenylalanine과 arginine, methionine과 glutamic acid, histidine과 lysine 간에는 유의 정상관, 그리고 isoleucine과 lysine 간에는 유의한 부상관이 있었다. 4. lysine 함량은 단백질 함량과 정산곤, isoleucine 함량은 단빅질 함량과 부상관을 보였으며, alanine, valine, leucine 함량은 지방함량과 각각 유의한 정산관을 보였다. 5. 대두 단백질은 7.5% acrylamide gel 전기영동에 의해 품종에 따라 12～16개의 구성분으로 분리되었으며, 이들중 주구성분들은 상대이동도가 0.06(a), 0.14(b). 0.24(d) 이었고, 구성분 b의 함량이 품종간에 가장 변이가 컸으며, 구성분 b는 그밖의 주요 구성분들의 함량과 부의 상관이 있었고, 구성분 a는 단백질 함량과 정상관이 있었다. 6. 종실단백질 구성분들의 조합 특성 면에서 공시 86품종은 11개 유형군으로 분류되었으며, 우리나라와 일본품종은 미국품종에 비해 단백질구성분 조성이 훨씬 다양하였다. 7. 이동도가 매우 빠른 단백질 구성분 o(Rm 0.77) p(Rm 0.81)를 모두 갖고 있는 품종은 3품종, 모두 갖고 있지 않은 품종은 1품종이었고, 나머지 82품종은 o나 p중 한 구성분을 갖고 있었으며 그 분포율은 30 : 65 이었는데 미국계 품종은 우리나라 품종에 비해 구성분 o를 간고 있는 비율이 현저히 적었다. 8. 대두 종실은 개화후 22일까지 완만히, 그 이후 20～30일간 급속히

• Journal of the Korean Society of Food Culture
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• v.23 no.4
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• pp.514-520
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• 2008

This study addresses the development of a soy hamburger patty containing enzyme-treated textured soy protein (TSP) as a meat analogue. In order to reduce the beany flavor and enhance the texture, TSP was treated with 0.3% Flavourzyme for 5, 10, 20, or 30 min. The degree of hydrolysis and the water holding capacity of the TSP increased with increasing hydrolysis time. The oil binding capacity of the TSP also increased with increasing hydrolysis time, approaching the maximal value, 175.82%, at 30 min, whereas that of pork scored with the lowest value of 128.67%. The volume of pork was reduced to 81.5% as the result of heat treatment, whereas that of the TSP increased to 140.57%. The values of 'L', 'b', and '${\Delta}E$' differed significantly (p<0.001) with heat treatment, but the 'a' values did not differ significantly. With regard to texture, the hardness values were highest in the pork hamburger patty (PHP), and were lowest in the soy hamburger patty (SHP) containing untreated TSP. The hardness of the SHP containing TSP treated for 20 min did not differ significantly from that of the PHP. The cohesiveness and gumminess of the SHP treated for 20 min were highest, whereas those treated for 10 min were the lowest. The gumminess of the SHP treated for 20 min did not differ significantly from that of pork. The chewiness of the PHP was the highest, whereas that of the SHP treated for 5 min was the lowest. In our sensory evaluation, PHP evidenced the highest scores, followed by the SHP treated for 30 min, as color, texture, beany flavor, and overall quality all improved as the consequence of increasing enzyme treatment duration. In conclusion, it is believed that SHP has great potential as a substitute for meat, in that the flavor, texture, and beany flavor of SHP did not differ significantly from those of PHP.

• Journal of Life Science
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• v.18 no.8
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• pp.1123-1131
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• 2008

This study was performed to confirm of biological function of black garlic, it heated for 11 days at $40{\sim}90^{\circ}C$ (first step: heate for 2 days at $90^{\circ}C$, second step: heated for 4 days at $80^{\circ}C$, third step: heated for 4 days at $60^{\circ}C$ and fourth step: heated for 1 day at $40^{\circ}C$). Samples were analyzed physico-chemical characteristics and antioxidant activity. Hunter L, a and b values were decreased during processing, and then inner part Hunter values were highly decreased at the second step. The moisture contents were decreased to 58.48${\pm}$0.41 g/100 g at fourth step. pH was also acidified to pH 4.22${\pm}$0.02, but O.D. value at 420 nm was increased during processing of black garlic. At fourth step, total phenolics and flavonoids contents were increased about 1.9 and 2.6 folds than first step sample. Also, total pyruvate and thiosulfinate contents were increased about 1.6 and 5.8 folds as change of total phenolic and flavonoid contents, respectively. Fructose contents were the highest level among free sugars and its contents increased to 2,454.45${\pm}$4.20 mg/100 g. Contents of sucrose and maltose were decreased during processing of black garlic. The contents of total minerals were the highest at fourth step (1,009.20${\pm}$6.91 mg/100 g) during its processing. Contents of glutamic acid, proline and aspartic acid were detected higher than other composition amino acids. Taurine and ethanolamine were not detected in the first step sample, but they were detected 0.88${\pm}0.60{\sim}1.06{\pm}$0.04 and 0.28${\pm}0.4{\sim}0.5{\pm}$0.09 mg/100 g in next processing step, respectively. DPPH radical scavenging ability of water and ethanol extracts from black garlic was increased during its processing. Abilities of DPPH radical scavenging were the highest in fourth step sample, its abilities were 67.40${\pm}$0.21% in 1,000 ${\mu}g/ml$ of water extracts. Reducing power was also significantly higher in water extract than ethanol extract on the whole.