• 한국식품저장유통학회지
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• 제24권4호
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• pp.505-509
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• 2017

Water vapor adsorption kinetics of vacuum-dried jujube powder were investigated in temperature and relative humidity ranges of 10 to $40^{\circ}C$ and 32 to 75%, respectively. Water vapor was initially adsorbed rapidly and then reached equilibrium condition slowly. Reaction rate constant for water vapor adsorption of vacuum-dried jujube powder increased with an increase in temperature. The temperature dependency of water activity followed the Clausius-Clapeyron equation. The net isosteric heat of sorption increased with an increase in water activity. Good straight lines were obtained with plotting of $1/(m-m_0)$ vs. 1/t. It was found that water vapor adsorption kinetics of vacuum-dried jujube powder was accurately described by a simple empirical model, and temperature dependency of the reaction rate constant followed the Arrhenius-type equation. The activation energy ranged from 50.90 to 56.00 kJ/mol depending on relative humidity. Arrhenius kinetic parameters ($E_a$ and $k_0$) for water vapor adsorption by vacuum-dried jujube powder showed an effect between the parameters with the isokinetic temperature of 302.51 K. The information on water vapor adsorption kinetics of vacuum-dried jujube powder can be used to establish the optimum condition for storage and processing of jujube.

• 한국식품영양과학회지
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• 제39권4호
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• pp.573-579
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• 2010

대학찰옥수수의 수확시기에 따른 전분특성을 규명하기 위하여 수확적기, 전기(-4일) 및 후기(+4일) 옥수수로부터 분리된 전분의 수율, 효소적 소화율, 물결합력, 팽윤력, 용해도 및 점도를 살펴보았다. 수확시기별 대학찰옥수수 전분의 수율은 43.21~52.73% 범위로 수확시기가 늦어질수록 높게 나타났으며, 아밀로펙틴의 함량은 90.79~92.83% 범위에서 증가하였다. 수확시기가 늦어짐에 따라 전분의 효소적 소화율과 용해도는 각각 81.43에서 80.58%와 10.23에서 9.23%로 감소하였으나, 전분의 물결합력과 팽윤력은 각각 227.94에서 244.88%와 24.75%에서 29.74%로 증가하였다. 점도는 최초 측정온도인 $90^{\circ}C$에서는 큰 차이가 없었으나, 전분 겔이 노화됨에 따라 점도는 증가하였으며, 수확시기가 늦어질수록 점도는 낮게 나타났다. 전분특성 관련 인자들 사이의 상관관계를 분석한 결과 높은 양 또는 음의 상관관계를 보였으며(p<0.01), 아밀로펙틴의 함량이 높을수록 효소적 소화율, 용해도 및 노화점도는 감소하였으나, 물결합력과 팽윤력은 증가하였다.

• 한국식품영양과학회지
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• 제42권3호
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• pp.378-383
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• 2013

벌나무의 에탄올 및 열수 추출물을 각각 제조하여 추출물별 항산화 활성을 비교하고, in vitro 및 in vivo에서의 알코올 분해능을 검토하였다. 벌나무 열수 및 에탄올 추출물의 총 폴리페놀 함량은 각각 $171.93{\pm}2.2{\mu}g/mg$, $152.69{\pm}1.25{\mu}g/mg$, 총 플라보노이드 함량은 각각 $7.51{\pm}1.34{\mu}g/mg$, $5.01{\pm}0.83{\mu}g/mg$이었고, FRAP값은 각각 $1.75{\pm}0.32{\mu}M/{\mu}g$, $1.67{\pm}0.28{\mu}M/{\mu}g$으로 나타났다. 벌나무 열수 및 에탄올 추출물은 DPPH 및 ABTS에 대해 높은 소거활성을 보였고, 지질과산화 억제활성이 높음을 알 수 있었다. 벌나무 열수추출물은 HepG2 세포에서 알코올에 대한 in vitro에서의 간세포 보호 효과가 있었고, 또한 알코올을 투여한 rat에서 벌나무 추출물을 투여하면 알코올 투여 30분이 경과한 후 알코올 투여군보다 혈중 알코올 함량이 유의적으로 저하되었다. 따라서 벌나무 추출물은 높은 항산화 작용을 하며, 알코올 분해 작용 및 알코올에 대한 간 보호 효과가 높은 것으로 생각된다.

• 한국식품영양학회지
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• 제30권4호
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• pp.771-779
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• 2017

The purpose of this study was to investigate and analyze the total phenolic content (TPC), antioxidant activities (FRAP, ABTS, and DPPH), and antibacterial properties of lotus (Nelumbo nucifera) extracts. Lotus leaves, stems, and seed pods were extracted with deionized water at $95^{\circ}C$, and with 70.5% ethanol at $85^{\circ}C$. The TPC ranged from 8.12 to 215.12 GAE mg/g. The ethanol extract of the seed pod had the highest TPC, and the TPC of the corresponding deionized water extract was 161.45 mg/g. FRAP values ranged from 104.03 to $3,546.39TEAC\;{\mu}mol/g$, ABTS radical cation scavenging activities ranged from 105.11 to $3,956.94TEAC\;{\mu}mol/g$, and DPPH radical scavenging activities ranged from 37.29 to $2,549.46TEAC\;{\mu}mol/g$. $EC_{50}$ values ranged from 0.26 to 9.63 mg/mL, and 0.31 to 21.21 mg/mL for ABTS and DPPH, respectively. The ethanol and deionized water extracts of the seed pod showed higher TPC and stronger antioxidant properties (FRAP, ABTS, and DPPH) than those of characteristic of the leaf extracts. The ethanol and deionized water extracts of the seed pod showed antimicrobial activity against Bacillus subtilis, Staphylococcus aureus, and Pseudomonas aeruginosa with inhibition zones of 9.0 to 14.0 mm, and the ethanol extract of the leaf showed antimicrobial activity against B. subtilis and S. aureus with inhibition zones of 9.0 and 10.0 mm, respectively. Thus, the lotus seed pod could be used to produce novel teas, and could be a potential source of therapeutic ingredients for food and medicine.

• Current Research on Agriculture and Life Sciences
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• 제33권2호
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• pp.57-63
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• 2015

안전한 천연물을 이용한 천연항산화제 개발 연구의 일환으로, 오크라, 엉컹퀴, 엄나무 및 줄풀 등 4종의 천연 약용식물 추출물의 항산화 활성을 측정해보았다. 추출물의 총 phenolic compounds 함량은 오크라와 엉컹퀴는 50% ethanol, 엄나무는 40% ethanol, 줄풀은 60% ethanol에서 최대용출을 나타내었으며, water 추출물에서 2.72~34.15 mg/g, ethanol 추출물에서 2.83~34.23 mg/g의 용출율을 나타내었다. 4종류 약용식물 water과 ethanol 추출물의 DPPH radical 소거능은 $50{\mu}g/mL$의 저농도에서 모두 74% 이상의 높은 소거활성을 나타내었다. ABTS radical cation decolorization을 측정한 결과, 4종의 약용식물 water 추출물과 ethanol 추출물 $100{\mu}g/mL$의 농도에서 모두 88% 이상의 높은 저해율을 나타내었다. 지용성 물질에 대한 항산화 효과를 측정하기 위해 antioxidant protection factor(PF)를 측정한 결과, 엉컹퀴 water과 ethanol 추출물 $50{\ddot{I}}g/mL$의 저 농도에서 각각 1.73과 1.76 PF로 다른 약용식물 보다 높은 항산화효과를 나타내었다. TBARs 생성 억제율을 측정한 결과 오크라를 제외한 3종의 약용식물 추출물 $50{\mu}g/mL$ phenolic 농도에서 80% 이상의 생성억제 효과를 나타내었다. 이러한 결과에 따라 다양한 약용식물 추출물이 항산화 및 기능성 식품 소재로 활용이 가능하다고 판단되었다.

• 한국식품영양과학회지
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• 제29권2호
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• pp.316-321
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• 2000

This study carried out to eluciate the cancer chemoprevention of Korean native fermented food, baechu kimchi using Comet assay (in other words, single cell microgel electrophoresis). For this purpose, baechu kimchi was fractionated by water, n-hexane, chloroform and ethyl acetate. 5 strains of dominant fermented bacteria were isolated from baechu kimchi. The water fraction, n-hexane fraction, chloroform fraction, ethyl acetate fraction and water insoluble fractions showed no antigenotoxicitie in non-tumoral normal 3T3 cells. Among 5 bacteria isolates from baechu kimchi, two isolates bacteria 1 and 2 strongly inhibited genotoxicity of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in non-tumoral normal 3T3 cells (p<0.05). Bacteria 3, 4 and 5 were also not antigenotoxic.

• 한국식품조리과학회지
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• 제30권6호
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• pp.695-703
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• 2014

Daebong persimmon puree (DPP) prepared from removing the astringency of persimmon was used as a substitute for water when making the dough of white pan bread using domestic wheat flour, and the resulting, quality characteristics were investigated. The moisture content of DPP was 96.69%, and the dough was made by various levels of substitution of DPP for water (0, 10, 30, 50 and 100%). During fermentation, the expansion power of the dough decreased with increasing DPP levels (p<0.05). The volume, specific volume, baking loss, and the L and ${\Delta}E$ values of the crust and crumb of the breads also decreased with increasing DPP levels. The hardness and chewiness of the bread containing 100% DPP (without water) showed the highest values, but the springiness, cohesiveness and resilience showed the opposite trends. In the difference tests, all attributes except air cell uniformity were significantly different (p<0.05). Bread made with 100% substitution of DPP for water achieved the highest scores for flavor, taste and overall acceptability.

• 한국식품영양학회지
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• 제11권3호
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• pp.354-358
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• 1998

우리 나라에서 쉽게 구할 수 있고, 값이 저렴하여 대중적으로 널리 이용될 수 있는 감잎으로부터의 열탕 추출물과 함께 탄닌을 분리하여 xanthine oxidase 활성을 측정함으로써 감잎의 통풍 예방효과를 살펴보았다. 감잎의 열탕 추출물을 농도별로 살펴본 결과 열탕 추출물의 농도가 증가할수록 저해효과가 증가하여 2.0mg 첨가시 82.4%의 높은 저해효과를 나타냈으며, 감잎탄닌도 감잎의 열탕 추출물과 마찬가지로 농도에 비례해서 santhine oxidase 저해효과가 증가하는 것으로 나타났다. 한편 감잎 열탕 추출물 및 감잎 탄닌은 xanthine oxidase에 대해 경쟁적 저해를 하는 것으로 나타났다.

• 한국식품영양과학회지
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• 제18권4호
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• pp.403-409
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• 1989

Dietary fiber(DF) content and their properties were analyzed in some common vegetables such as Squash(leaf), Water cress, Garland chrysanthemum, Leek and sweet potato(stem). DF was analyzed by the method of detergent fractionation. Values for neutral detergent fiber(NDF), acid detergent fiber(ADF), lignin, hemicellulose were obtained. NDF for most samples was $13.83%{\sim}24.31%$, ADF was $11.99%{\sim}21.03%$, lignin was around $0.56%{\sim}3.00%$, hemicellulose was about $1.33%{\sim}3.88%$, cellulose was $9.08%{\sim}14.87%$ except sweet potato(leaf) (20.47%). This paper describes two properties of the fiber-of commonly eaten vegetables ; water-holding capacity(WHC) and metal binding. The capacity of the acetone dried powder (ADP) to hold water was estimated. The WHC measurements differed from 7.49 per 9 of ADP for Water cress to 11.09 per 9 of ADP for Leek. The binding of Fe, Zn in NDF. ADF obtained from five fiber sources was examined under two pH conditions ; 1) pH2.1, 2) pH6.1. Fe, Zn binding increased with higher pH and differed from DF sources.

• 한국식품조리과학회지
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• 제23권1호통권97호
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• pp.1-8
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• 2007

Extraction conditions were optimized using response surface methodology for preparing high-quality, hot water extracts from cultivated Chrysanthemum indicum L. petals. A fractional factorial design was applied to investigate the effects of added sample ratio ($X_1$), extraction temperature ($X_2$) and extraction time ($X_3$) variables on extract properties, such as, soluble solid contents ($Y_1$), sugar content ($Y_2$), ?E ($Y_3$), turbidity ($Y_4$), total phenol ($Y_5$) and DPPH ($Y_6$). Second-order models were employed to generate a 3-dimensional response surface for dependent variables and their coefficients of determination ($R^2$) ranged from 0.8408${\sim}$0.9914. The range of optimum conditions at $80^{\circ}C$ extraction for maximize characteristics of hot water extracts was 2.3${\sim}$2.7 g and 9.2${\sim}$11.2 hr.