• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.310-316
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• 1994

The phenolic substances contents of 45 plant foods in Korean diet were determined by different methods. Total phenolics contents by Folin-Denis method were $0.1{\sim}5.8%$ (dry matter basis), in which persimmon leaf, chestnut's inner skin, Chinese quince, walnut, sunflower seed and arrowroot exhibited the higher levels above 2%. Condensed tannin contents by vanillin method were $0{\sim}48%$, in which Chinese quince and chestnut's inner layer gave very high levels. Protein-precipitable phenolic substances ranged from 0.4% to 2.2%, in which chestnut's inner layer, walnut and Chinese quince had the highest content. The ability of phenolics to form precipitate was higher with pepsin and albumin than with trypsin. Among different phenolics content, total phenlolics correlated significantly with protein-precipitable phenolics (r=0.65) and condensed tannin (r=0.56). Chinese quince, chestnut's inner skin and sorghum showed a relatively lower degree of polymerization, as expressed by vanillin/FolinDenis ratio. Processed foods from buckwheat, acorn, mugwort and arrowroot showed a lower content of phenolic substances, suggesting a negligible adverse effect on the bioavailability of food proteins, if any.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.229-235
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• 2007

관개나 수분수지 규명을 위한 기본적인 자료는 토양수분 함량이다. 그러나, 포장상태에서의 토양수분 함량은 직접 측정하는 것이 쉽지 않기 때문에 많은 경우 건조기를 이용한 중량수분 함량측정 방법을 이용하거나 토양수분 포텐셜 측정용인 텐시오미터를 이용한 토양수분의 에너지 특성을 관개에 활용하는 것이 현실이었다. 중량수분 함량은 시료를 채취해서 건조하기 때문에 시료채취 당시의 토양수분 함량을 아는 것이 어렵고, 토양수분 포텐셜은 에너지를 측정하는 것이기 때문에 이 역시 토양의 수분함량을 얻는 것이 불가능 하다. 따라서, 최근에 이런 측정상의 어려움을 극복하기 위해 여러 나라에서 포장에서의 토양수분 함량을 직접 측정하는 다양한 센서를 개발하고 있고 있다. 그 중 몇 가지는 현재 우리나라에 공급되고 있는데, 가격 등의 문제로 별로 알려져 있지는 않다. 센서는 현장에서 수분함량을 파악할 수 있는 장점이 있기 때문에 관개에 직접 적용이 가능하며 자동화시설이나 수분수지 모형 산정에도 활용할 수 있다. 본 시험은 우리나라에 소개되어 있는 몇 가지의 토양수분 측정용 센서를 현장에서 코어를 이용해 측정한 용적수분 함량과 비교하여 센서의 정확도나 이용 가능성을 검정하고자 하였다. 코어를 이용해 실측한 토양 용적수분 함량과 비교하고자 7종의 센서를 선택해 실험에 이용하였다. 가격이 비싼 것으로 알려진 TDR 형태의 센서가 2종이었으며, 나머지 5종은 FDR 형태의 센서였다. TDR 센서는 Soilmoisture사에서 제작한 MiniTrase와 Imko 사의 Trime이고, FDR은 Sentek사에서 개발한 EasyAG, EnviroSCAN과 Delta-T사에서 제작한 PR-1과 WET-2 및 Decagon사에서 제작한 $ECH_2O$ 센서였다. 실헙방법은 본량사양토인 포장에서 건조한 상태인 시험구와 물이 포화된 시험구를 만들어 놓고, 그곳에서 센서 종류별로, 측정 깊이별로 토양의 용적수분 함량을 측정하고, 센서로 측정한 위치 바로 옆에서 코어를 이용해 토양시료를 채취하고 이를 건조기에 건조해 용적수분 함량을 측정하였다. 비교결과 TDR인 MiniTrase가 결정계수$(r^2)$가 0.964이고 표준오차(SE)가 0.01로 좋은 결과를 보여줬고 WET-2가 $r^2$와 SE가 0.932와 0.013이였으며 EasyAG는 0.877과 0.0211, EnviroSCAN은 0.803과 0.0259의 값을 보였다. 일반적으로 토양수분 함량 측정오차가 1% 미만인 센서가 정확한 수분함량 해석을 유도할 것이지만 위의 센서 중 MiniTrase를 비롯한 4개의 센서 정도가 토양의 수분 함량을 측정하는데 유용할 것이라는 결론을 얻었다.

• Food Science and Preservation
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• v.8 no.4
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• pp.469-474
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• 2001

Chemical composition of the water extract of three different kinds of bamboos was investigated to access nutritive sources. Bamboo stalks and leaves were extracted massively and concentrated to 3°Brix, and crude protein and fat contents of the extracts were respectively 0.56∼0.69% and 0.28∼0.58%. Main mineral contents of the extracts were K, P and Mg in order, and those were the highest in Wangdae stalks. In free sugar analysis of the extracts, Maengjongjuk stalks contained 1.1% sucrose, Somdae stalks contained 0.51% fructose and Wangdae stalks contained 0.6% glucose as the highest level. Organic acid contents of the extracts showed high level in acetic and malic acid which were 54.0 and 44.2mg% in extracts of Wangdae stalks respectively. Among amino acids, aspartic acid was contained the highest level in stalk extracts, and their concentrations were 42.2, 39.9 and 34.6mg% in Wangdae, Somdae and Maengjongjuk respectively. In leaf extracts, glutamic acid concentrations were higher than the other amino acids, and those were 19.3, 18.5 and 15.7mg% in Maengjongjuk, Wangdae and Somdae, respectively.

• Elastomers and Composites
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• v.48 no.3
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• pp.216-220
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• 2013

The phase separation in Wood Flour-Polymer Composite (WPC) was investigated and the reasons for change in mechanical properties with the content of wood flour were explored. The wood flour-polypropylene composite samples with different wood flour contents were prepared. From differential scanning calorimetry (DSC) thermograms of WPC samples, the trend of crystallinity and melting temperature ($T_m$) were analyzed. The crystallinity and melting temperature increased and then decreased as the content of wood flour increased. From these results, it was confirmed that at the low wood flour content the wood flours were dispersed into the polypropylene matrix but at the high wood flour content, the phase separation between polymer and wood flour phases appeared. The tensile strength of WPC samples was continuously decreased with the increase of wood flour content. At a low wood flour content, the low interfacial bonding and the decrease in crystallinity were the main reasons for the decrease in tensile strength with the increase of wood flour content. At a high wood flour content, the decrease in tensile strength resulted from the interfacial defects between the polymer and wood flour phases. The impact strength of the WPC sample showed the maximum behavior with the content of wood flour. At a low wood flour content, the impact strength was enhanced owing to the decrease in brittleness, which results from the decrease in crystallinity. At a high wood flour content, however, the impact strength decreased due to phase separation.

• Food Science and Preservation
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• v.10 no.4
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• pp.534-539
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• 2003

This study was conducted to analyze components of the fruit of Etaeagnus multiflora to form a part of studies on the nutritional and functional materials of fruits and leaves of E. multiflora, and the development of a functional food. The moisture content of the fruit was 82.34%, and the content of carbohydrate, crude protein, lipid and ash was 15.4, 1.29, 0.79 and 0.54%, respectively. The pH of the fruit extract was 3.29, acidity 0.64%, and brix 14.0. Total sugar was contained 1.03/100g and reducing sugar was 3.27 g/100g. The content of soluble protein was 0.48 g/100g, and polyphenol was 0.28 g/100g. The glucose and fructose as a free sugar was 401.96 and 370.34 mg/100g, and account for a great portion of the components. Total content of free sugary was 0 mg/100g. The total amount of organic acid was 294.44 mg/100g, and the content of citric acid was 265.01 mg/100g, malic acid 18.16 mg/100g, and succinic acid 8.50 mg/100g. In the free amino acid, the concentration of serine was the highest (13.93mg/100g), and alanine, aspartic acid, cystine and methionine were high in the above order. The content of ascorbic acid was 131.35 mg/100g and that of dehydroascorbic acid was 431.37 mg/100g. Potassium, magnesium and sodium content were 627.44, 140.28, and 56.70 mg/100g, respectively.

• Food Science and Preservation
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• v.16 no.1
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• pp.33-39
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• 2009

To evaluate the quality of brown rice vinegar made by traditional fermentation in terms of Zymotechnic data and material content, vinegars prepared using a traditional leavening agent and yeast were compared. Amino acid, total nitrogen, free sugar, organic acid, and mineral levels were assessed, with vinegars made with initial brown rice contents of 12.36% (w/v). Vinegar made using Nuruk as fermenting agent (traditional fermentation, TF), with a brown rice content of 20% (w/v), and vinegar prepared using yeast for fermentation (control fermentation, CF), with a brown rice content of 12% (w/v) were compared. TF vinegar had a total nitrogen content about 2.0.4.6-fold that of CF vinegar. Total nitrogen in TF vinegar was 350.460 mg/100g, and in CF vinegar the level was 100.140 mg/100g. TF vinegar had more minerals, free sugars, and amino acids compared with CF vinegar. When free sugar was assessed, TF vinegar had a glucose level of 3.45 g/100g, double that of CF vinegar. Amino acid levels were five-fold higher in TF vinegar then in CF vinegar. When brown rice content was 36% (w/v), the amino acid level was $6088.22\;{\mu}g/mL$ in TF vinegar and $1194.05\;{\mu}g/mL$ in CF vinegar.

• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1251-1257
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• 2000

Red pepper powder (Capsicum annuum L.) is one of the most important ingredients for making kimchi. Various aspects of the quality of the red pepper powders (RPP) produced in Korea depending on the varieties and producing districts were compared. The evaluated intrinsic elements were vitamin C, carotenoid, capsaicinoid and free sugar contents and the extrinsic element was ASTA (American Spice Trade Association) colors. The vitamin C content was the highest in Johong (230 mg%) RPP among the varieties and Youngyang (263 mg%) RPP among the producing districts. Myungpum RPP that contains high level of carotenoids showed increased level of ASTA color, it exhibited positive relationship between carotenoid contents and ASTA color. Capsaicinoid level in RPP was the highest in var. Chungyang (126.1 mg%) that was usually used soup and pungent cook. Free sugar contents which is related to sweetness were the highest in Youngyang RPP Youngyang RPP that preferentially used in the preparation of kimchi showed the highest levels in vitamin C, carotenoid, ASTA color, and free sugar contents, but the contents of capsaicinoid was the lowest.

• Korean Journal of Breeding Science
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• v.40 no.3
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• pp.269-277
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• 2008

Amino acid composition in grain of Korean native rice core collections was evaluated to identify the useful genotypes for quality enhancing rice breeding and value-added food development. Large variations were found in the contents of 16 amino acids among 388 genotypes tested with 14.9% of the minimum coefficient of variation (CV), and the contents of methionine and histidine showed the highest CV and the second high, respectively. The average values of total amino acid, total essential amino acid, lysine and threonine contents of Korean native rice collections were almost similar with those of cultivating japonica rice, Saechucheong. Among 388 native core collections Baekkokna, Daesona and Saducho were identified as high amino acid germplasm in total amino acid, total essential amino acid, lysine and threonine contents. And Seoksanjo and Sodujo were identified as low amino acid collections. Rice collections showing purple apiculus color tended to distribute in lower serine, proline, glutamic acid, glycine, alanine, valine, leucine, phenylalanine, arginine, and total amino acid contents compared with those of yellowish apiculus color collections. The glutinous rice collections showed the tendency of higher contents of serine, glutamic acid, alanine, valine and leucine compared with those of non-glutinous collections.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.69-69
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• 2019

해당화 열매를 숙기 별로 과육의 항산화물질 함량과 씨앗의 지방산 함량을 측정하여 평가하였다. 과육의 1,1-diphenyl-2-picrylhydrazyl (DPPH) 항산화능을 갈산 환산농도로 나타내면 미성숙 과육은 $4.36{\pm}0.03mg/g$, 성숙 초기 과육은 $4.54{\pm}0.37mg/g$, 성숙 중기 과육에는 $4.78{\pm}0.21mg/g$, 성숙 후기에는 $4.30{\pm}0.22mg/g$ 범위로 항산화능을 보여주었다. 항산화능력은 성숙중기에서 높은 함량을 보여주었고 성숙함에 따라 감소함을 보여주었다. 미성숙, 성숙 초기는 유의한 걸로 나오지만 성숙 중기와 성숙 후기은 다른 성숙도와 유의하지 않았다. 총 페놀 함량의 미성숙 과육은 $1.60{\pm}0.03mg/g$, 성숙 초기 과육은 $1.80{\pm}0.08mg/g$, 성숙 중기 과육에는 $2.03{\pm}0.67mg/g$, 성숙 후기에는 $1.53{\pm}0.07mg/g$ 범위로 폴리페놀이 존재하였다. 성숙 초기에 제일 높은 항산화능력과 폴리페놀 함량을 보여주고 있으며 성숙할수록 항산화능력과 총 페놀 함량이 떨어지는 것을 알 수 있다. 씨앗의 지방산 함량은 리올레산, 리놀렌산, 올레산, 팔미트산 순으로 많았다. 리올레산은 미성숙 씨앗은 전체 함량 중 56.46%, 초기 과육 씨앗에는 54.26%, 중기 과육 씨앗에는 51.67%, 후기 씨앗에는 50.75%의 함량을 가지고 있다. 리올렌산은 미성숙 씨앗은 전체 함량 중 18.80, 초기 과육 씨앗에는 17.96%, 중기 과육 씨앗에는 18.90%, 후기 씨앗에는 21.42%의 함량을 가지고 있다. 올레산은 미성숙 씨앗은 전체 함량 중 13.54%, 초기 과육 씨앗에는 20.78%, 중기 과육 씨앗에는 22.44%, 후기 씨앗에는 20.81%의 함량을 가지고 있다. 팔미트산은 미성숙 씨앗은 전체 함량 중 6.80%, 초기 과육 씨앗에는 3.40%, 중기 과육 씨앗에는 3.37%, 후기 씨앗에는 3.32%의 함량을 가지고 있다. 리올레산은 미성숙 시기에 가장 많았고 리올렌산은 후기에 올레산은 중기에, 팔미트산은 초기에 많았다.

• Journal of Ginseng Research
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• v.13 no.2
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• pp.178-182
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• 1989

Red ginseng products manufactured by the Korea Ginseng and Tobacco Corporation were analyzed to determine the crude saponin , total saponin and ginsenoside contentents by gravimetry, spertrometry and HPLC, respectively, to see if effective quality control of the components in the products can be achieved. Medicinal powders, powders, tablets and capsules which were made from ginseng powder showed similarity in saponin content, the ratio of PD to PT saponin, and the ginsenoside content and composition, while extract powder, extract, extract tea, extract pills and tea, which were made of ginseng extract, showed difference in saponin content, ratio of PD to PT saponin, and the content and composition of ginsengside. It is, accordingly, believed that ginseng products which are uniform in contents and saponin composition can be produced by carrying out strict quality control throughout the processes of making raw red ginseng into final products.