• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2000.11a
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• pp.129-130
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• 2000

기존에 발표된 논문에서 섬유를 고해하기 전에 물리적 전처리를 함으로써 같은 여수도에서 섬유길이의 손상없이 섬유의 WRV 가 증가하는 사실을 발표한 바 있다. 이러한 Hobart m mixer를 이용한 섬유의 전처리가 과연 화학펄프섬유의 건조시 발생하는 각질화 ( (Homification)를 역전시킬 수 있는지를 본 연구에서 알아보았다. 현재까지의 실험결과 침 엽수 표백화학펄프의 경우 건조시 각질화가 많이 일어나지 않은 경우 (섭씨 80도의 저온에 서의 건조) 에는 거의 완벽한 각질화의 역전이 일어났지만 건조온도가 높아져서 심한 각질 화가 예상되는 경우 (섭씨 110도) 에는 물리적 전처리의 효과가 나타나지 않았다. 따라서 H Hobart mixer를 이용한 물리적 전처리는 각질화가 많이 진행되지 않은 경우에는 섬유의 불 리적 특성올 회복시킬 수 있는 수단이 될 수 있다고 판단되었다.

• Journal of the Korean Wood Science and Technology
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• v.9 no.4
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• pp.1-21
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• 1981

Exterior grades of Douglas-fir and aspen plywood were impregnated with interior fire-retardant chemicals and redried under low-, intermediate-, and high-temperature drying conditions. Fire-retardant treatments included borax-boric acid, chromated zinc chloride, minalith, pyresote, and a commercial formulation. Drying processes included kiln and press-drying. Evaluated were drying rates and defects generated. The borax-boric acid and the commercial treatments redried at rates similar to water-treated controls. Other salt treatments were significantly slower drying and more defect prone. Chromated zinc chloride treatment was consistently the slowest drying and most defect prone. Press drying was three times faster at an equivalent temperature level. However, thickness shrinkage doubled because of 50 1b/in. platen pressure.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.2
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• pp.101-108
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• 1984

In order to study the optimal conditions of processing and storage for boiled and dried anchovy (Engraulis japonica) with high protein digestibility, the contents of trypsin indigestible substrate (TI) and in vitro apparent protein digestibility were determined. Peroxide value (PoV), TBA number and nonenzymatic brown pigments, that accounted for important antinutritional factors, were also measured and confirmed the relationship between those factors and formation of TI or in vitro protein apparent digestibility. The results were as follows; Samples boiled for 5 minutes showed the lower content of TI than the other samples boiled for 0.5 min. or 1 min. Hot air dried products had a lower TI content in comparison with the other dried ones such as sun dried or freeze dried products. It was revealed that the lower temperature ($8{\pm}1^{\circ}C$) did not affect to a great degree of forming TI and falling in vitro digestibility comparing to high temperature ($26{\pm}1^{\circ}C$) during storage. The lowest TI content (0.173 mg/g solid) was noted in the samples for 5 minutes and then sun drying after 56 days storage at $9{\pm}1^{\circ}C$. A rapid decrease of in vitro protein digestibility occurred within 0.5 min. of boiling and showed the value $85.3\%$. Freeze dried samples possessed the highest in vitro protein digestibility ($85.9\%$), when compared to sun dried or hot air dried products. Fat oxidation and nonenzymatic browning were proceeded with the various boiling times, drying methods and storing temperatures. It was noted that boiling for 5 minutes and freeze drying accelerate the fat oxidation significantly. More nonenzymatic brown pigments was developed in samples boiled for shorter time (0.5 min.) and that stored at high temperature ($26{\pm}1^{\circ}C$) than the other products. Therefore, fat oxidation and nonenzymatic browning assumed to be a major inhibitory reaction in enzyme digestion and those might be an important role in forming TI in boiled and dried anchovy products during processing and storage.

• Food Science and Preservation
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• v.8 no.4
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• pp.351-355
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• 2001

This study was carried out to examine the of quality on the dried Omija according to its package materials and storage plates. The changes of moisture contents, anthocyanin content, molds damage rates, and color values were measured during storage. In the sealing up by the P.E file, the moisture contents of the dried Omija had just a little differences among the storage places, but in the gauze bag remarkably as the storage period goes on, especially in this case, 8 months later since the storage in the cool chamber, the damage rates of the dried Omija by the mold was 9.0%, twice as much as in the indoor bag packaging it was increasand after 10 months, that was lather high in the indoor and warehouse. The anthocyanin content of the dried Omija after the storage of 10 months was the highest at 0.05mm black P.E film package in the cool chamber, which was 55.7 mg/100g, but in the indoor and warehouse 39.7, 45.0mg/100g, respectively. These results show thats the storage conditions had an important effect on the quality of the dried Omija during the long-term storage.

• Journal of the Korean Wood Science and Technology
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• v.46 no.3
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• pp.213-220
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• 2018

In order to use Pitch pine (Pinus rigida Miller) as the material of the structural glued laminated timber, the effect of the amount of resin exudation due to storage time after the planning and the knot of the lamina were evaluated on the bonding properties of the glued board with resorcinol resin. For Pitch pine that was dried at high temperature ($120{\sim}95^{\circ}C$) and low temperature ($65{\sim}50^{\circ}C$), the flat sawn(tangential section) showed higher amount of resin exudation than the quarter sawn(radial section). And the low temperature drying wood showed higher resin exudation than the high temperature drying wood. The low and high temperature drying wood showed the highest amount of resin exudation on the 3rd day and 7th day, respectively and they were gradually decreased. However, there were no significant differences from 15 to 90 days. Adhesion performances were low until 2~3 days with high exudation of resin, but there were no significant differences after 15 days. Both high temperature and low temperature drying woods satisfied the Korean standard regardless of the storage time. The adhesive strengths of the laminating parts including knots were higher than those of KS criteria, but the wood failures were not satisfied the KS standard. Adhesive performances according to the laminating combinations (quarter sawn + quarter sawn, flat sawn + flat sawn, quarter sawn + flat sawn) were better than those of KS criteria in all laminating combinations in both high temperature and low temperature drying woods.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.3
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• pp.311-317
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• 1986

To obtain the basic informations on the variation of rice grain shattering under different environmental conditions, several experiments were carried out from 1982 to 1985. The degree of grain shattering was significantly differed depending upon the harvesting time after heading in some rice varieties. It appeared that the ratio of grain shattering was greatly affected by the drying period after harvesting; the ratio of grain shattering of sun-dried seeds for 6 days after harvesting was higher than those of the just harvested seeds. Grain shattering was increased at high level of nitrogen and decreased with delay in transplanting date. Yearly differences in grain shattering was more clearly recognized in easy-shattering varieties in comparison with those of non-shattering varieties. Rice grain shattering also increased by the low temperature treatment (l7/15$^{\circ}C$, day/night) at booting stage, 5 to 11 days before heading. A rice variety, Milyang 23, belong to easy shattering group was more pronounced at the low temperature condition with shading. In general, it was always possible to classify the cultivar differences between easy-shattering and non-shattering groups regardless of any environmental condition. Thus results suggested that rice grain shattering will be largely governed by genetic factors.

• Journal of Applied Biological Chemistry
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• v.57 no.4
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• pp.325-329
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• 2014

To maintain the quality of sweet persimmon during storage, the samples were treated with a combination of 50 ppm $ClO_2$ and 0.1% fumaric acid after harvest, packaged with low density polyethylene film, and stored at $1{\pm}1^{\circ}C$ for 35 days. The combined treatment reduced the populations of total aerobic bacteria, yeast and molds by 1.82 and 2.07 log CFU/g, respectively, compared to the control. During storage, hardness of all samples decreased, but total soluble solids and weight loss were not significantly different among treatments. In addition, high-quality dehydrated sweet persimmon was prepared using red algae extract as a dehydrating agent. The rehydration ratio and vitamin C content of red algae extract-treated sample were greater than those of hot-air dried sample. These results suggest that the combined treatment of $ClO_2$ and fumaric acid can be useful for maintaining microbiological safety of sweet persimmon during storage and dehydration of sweet persimmon slices using red algae extract is an efficient drying method for the preparation of high-quality dehydrated sweet persimmon.

• Food Science and Preservation
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• v.22 no.5
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• pp.708-713
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• 2015

To provide the basic data to dry vegetate the sweetpotato leaves, the total contents of tannin, flavonoid and polyphenol in the methanol extract from the hot-air dried sweetpotato leaves were analyzed and DPPH radical scavenging activity, ABTS radical scavenging ability, nitrite scavenging ability, and others were comparatively analyzed. The total tannin content was decreased from Shinmi of 10.87 mg/g at $40^{\circ}C$ to 7.28 mg/g at $70^{\circ}C$ and the total flavonoid was decreased from Hayanmi of 55.37 mg/g at $40^{\circ}C$ to 39.63 mg/g at $70^{\circ}C$. That is, the low temperature drying contained more of these substances than in the high temperature drying. The DPPH radical scavenging activity was the highest in Shinmi and Hayanmi of 84.33% and 85.25% at $40^{\circ}C$, and the ABTS radical scavenging ability was a high value of over 80% in the treatment plot at $40^{\circ}C$. The nitrite scavenging ability was highest in Shinmi and Hayanmi of 76.15% and 73.74% at $40^{\circ}C$ but low at $70^{\circ}C$. That is, the antioxidant effect of the hot-air dried sweetpotato leaves was high in the sample of $40^{\circ}C$ and low in the sample of $70^{\circ}C$. Affected by the drying temperature, the high antioxidant effect is resulting from the little decrease of active ingredient when drying at low temperatures.

• Journal of Biosystems Engineering
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• v.8 no.1
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• pp.47-60
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• 1983

상온통풍(常溫通風)을 이용(利用)한 In-bin drying에 대(對)한 많은 실험결과(實驗結果)에 의(依)하면 우리나라 10월(月)의 기상조건(氣象條件)은 저온건조(低溫乾燥) system에 적합(適合)한 건조능력(乾燥能力)을 가지고 있는 것으로 나타났다. 최근(最近) Computer를 이용(利用)한 Simulation model이 개발(開發)되어 건조현상(乾操現象)에 관(關)한 경제적(經濟的)이고 효율적(效率的)인 분석(分析)이 가능(可能)하게 되었다. 이러한 분석결과(分析結果)에 의(依)하면 초기함수율(初期含水率)이 높은 벼를 Full-bin을 이용(利用)한 상온통풍건조(常溫通風乾操)를 할 경우(境遇) 건조기간(乾燥期間)이 길어지며 bin내(內)의 상층부(上層部) 곡물(穀物)이 변질(變質)되는 문제점(問題點)이 발생(發生)하였다. 또한 벼의 수확작업체계(收穫作業體系)가 관행(慣行) 및 Binder작업체계(作業體系)에서 점차(漸次) Combine작업체계(作業體系)로 전환(轉換)되어감에 따라 포장(圃場)에서의 건조(乾燥)가 어려우며 예취(刈取), 탈곡작업과정(脫穀作業過程)에서의 기계적(機械的)인 곡물(穀物) 손실(損失)을 줄이기 위(爲)하여 함수율(含水率)이 비교적(比較的) 높은 벼를 수확(收穫)하여야 한다. 본(本) 연구(硏究)의 목적(目的)은 상온통풍건조(常溫通風乾燥)에 있어서 건조능력(乾燥能力)을 증가(增加)시키기 위(爲)하여 곡물(穀物)을 일정기간(一定期間) 나누어서 bin에 넣고 건조(乾燥)를 하는 Layer drying의 Simulation model을 개발(開發)하고 이 Model에 수원지방(水原地方)의 7년간(年間) 평균(平均) 기상자료(氣象資料)를 입력(入力)시켜 곡물(穀物)의 초기함수율(初期含水率), 투입량(投入量), 투입기간(投入期間)의 변화(變化)에 따른 Layer drying현상(現象)을 규명(糾明)하는데 있다. Simulation에 사용(使用)된 bin의 크기는 직경(直徑) 2m, 깊이 1.5m이며 송풍(送風)팬의 용량(容量)은 0.5HP이었다. Simulation분석(分析) 결과(結果)를 요약(要約)하면 다음과 같다. (1) Layer drying의 Simulation model을 개발(開發)하였으며 이 Model은 벼의 상온통풍건조(常溫通風乾燥) 실험(實驗)에서 함수량(含水量) 변화(變化)의 이론치(理論値)와 실제실험치(實際實驗値)가 잘 일치(一致)하였다. (2) 곡물투입기간(穀物投入期間) 1일(日)을 Full-bin drying으로 간주(看做)할 때 Layer drying의 건조성능(乾燥性能)은 Full-bin보다 높은 것으로 나타났다. (3) 연속송풍(連續送風)(24시간(時間))을 할 경우(境遇) 곡물투입기간(穀物投入期間)이 증가(增加)함에 따라 건조기간(乾燥期間)의 감소경향(減少傾向)은 단속송풍(斷續送風)인 경우(境遇)보다 적었지만 건조기간(乾燥期間)은 단축(短縮)되었다. 그러나 건조(乾燥)에너지의 소모(消耗)는 단속송풍(斷續送風)일 때보다 크게 나타났다. (4) 단속송풍(斷續送風)(9 : 00AM~6 : 00PM)일 경우(境遇) 곡물투입기간(穀物投入期間)을 증가(增加)시키면 건조기간(乾燥期間)이 크게 줄어 들었다. (5) 곡물(穀物)의 초기함수율(初期含水率)이 21% 이하(以下)일 경우(境遇) 연속(連續) 및 단속송풍(斷續送風)에서 건조기간(乾燥期間)의 차이(差異)가 별로 없었다. (6) 곡물(穀物)의 초기함수율(初期含水率)이 높으면 Full-bin drying에서는 상부층(上部層)에 곡물(穀物)이 변질(變質)될 우려(憂慮)가 있으나 Layer drying에서는 곡물투입량(穀物投入量)을 조절(調節)하면 이것을 방지(防止)할 수 있었다. (7) 건조(乾燥)가 완료(完了)된 후(後) 층별(層別) 최종곡물(最終穀物) 함수율(含水率)은 모든 건조조건(乾燥條件)에서 동일(同一)하였으나 bin의 하부층(下部層)은 과건조(過乾燥) 물상(物象)을 일으켰다.

• Korean Journal of Food Science and Technology
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• v.46 no.3
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• pp.303-308
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• 2014

This study determined the antioxidant levels and activities of hot water aronia extracts by different drying methods such as sun drying, sun drying after steam treatment, freeze-drying, and oven drying. The total polyphenol content, calculated as gallic acid equivalent, was the highest in the freeze-dried sample (910 mg), followed by sun-dried after steam treatment (779 mg), sun-dried (769 mg), and oven-dried (757 mg) samples. Similar patterns were observed for the total flavonoid and anthocyanin contents. Freeze-dried aronia samples contained the highest polyphenol, flavonoid, and anthocyanin contents as compared to the samples dried by other methods. All antioxidant activities were found to increase in a dose-dependent manner. For the hot water-extracted freeze-dried aronia powder (200 mg/mL), the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radicalscavenging activities were 65.5% and 61.7% and the hydroxyl and superoxide anion radical-scavenging activities were 50.5% and 52.1%, respectively. These results suggest that comparatively, freeze-drying is a better method for preserving the bioactive components and the antioxidant activities of aronia.