• Journal of Life Science
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• v.18 no.8
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• pp.1106-1114
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• 2008

The antioxidants activities in water and 95% ethanol extracts of wa-song (Orostachys japonicus A. Berger) dried by sun, hot air and lyophilization were measured in vitro reaction system. In reaction system containing linoleic acid, the antioxidant activities against lipid oxidation enhanced in proportion to storage time. The antioxidant activity of ethanol extracts was higher than that of water extracts. In the drying methods, wa-song extracts showed higher antioxidant activity in the other of hot air-dried, lyophilized and sun-dried. The lipid oxidation system containing the promoting factors, such as $Fe^{+2}$ and $Cu^{+2}$ions, also showed that the ethanol extract of hot air-dried wa-song possessed the highest antioxidant activity. Soybean oil and lard being added with various levels (0.1, 0.5 and 1.0 g/100 g) of the ethanol extract of hot air-dried wa-song were stored at $60^{\circ}C$ (for 28 days) or $180^{\circ}C$ (for 48 hr). Its extract appeared to lower the acid value of soybean oil, wheras it failed to lower the acid value for lard at early storage time, but it was lower than control and BHT after 28 days. Anicidine value and peroxide value were lower soybean and lard added wa-song extract than control and BHT for storage for 28 days at $60^{\circ}C$. In 28 days, its value was significantly decreased in proportion to sample concentration. TBA value was increased during storage time at $60^{\circ}C$, but it was significantly decreased by sample concentration after storage 36 hours at $180^{\circ}C$ storage. Therefore results suggest ethanol extract of hot air-dried wa-song could be potential candidates for natural antioxidants for materials containing lipid.

• Food Science and Preservation
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• v.15 no.3
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• pp.340-346
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• 2008

This study investigated the microbial safety of apple snails and intermediate-moisture-content apple snail products subjected to various treatments, according counts of total bacteria, Escherichia coli, mold and yeast during storage at 4C Heating of raw apple snails at 95C for 5 min increased the storage period in relation to total bacteria, E. coli, mold and yeast-cell growth. Addition of 10% NaCl and 50% vinegar increased the microbial safety of apple snails. Microorganisms were not detected for 14 weeks in vacuum-packaged intermediate-moisture-content apple snail products stored at either 4C or 30C. These results suggest that heat treatment of raw apple snails, soaking in 10% NaCl and 50% vinegar solutions, and vacuum-packaging increases the shelf-life and microbial safety of apple snail products.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.149.1-149
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• 2003

방사선에 의한 식품 저장은 이미 그 건전성과 경제적 타당성이 인정되어 세계 여러나라에서 실용화되고 있다. 고사리(Pteridium aquilinum)는 참고사리과에 속하는 다년생 양치식물로서 봄철에 어린잎과 줄기를 삶아 물에 담구었다가 건조시켜 저장하였다가 이용하고 있다. 현재 유통되고 있는 건고사리는 수확, 건조 및 저장 중에 비위생적인 관리 등에 의해 미생물의 증식 및 해충의 발생 등으로 품질이 크게 저하되어 저장상 많은 어려움을 안고 있다. 선행연구에서 방사선 조사된 건고사리는 불림시 연화현상이 나타났으므로, 본 실험에서는 Co-60감마선을 건고사리에 조사하여 습열조리 조건에 따른 연화 특성을 분석하였다. 즉, 건고사리에 조사선량을 0, 3, 5, 7kGy로 달리 하여 조사하였고 조리온도, 조리 시간에 따른 연화정도 및 연화에 따른 활성화 에너지를 분석하였다. 결과 조사선량이 높을 수록 경도는 대조구에 비해 유의적으로 감소하였는데 조리온도, 시간 및 조사선량이 증가할수록 감소하였다. 활성화에너지는 조사선량이 증가함에 따라 감소하여 건고사리의 가열 조리시 에너지가 감소 됨 이 확인되었다.

• Korean Journal of Plant Resources
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• v.14 no.3
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• pp.251-258
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• 2001

Predehydration effects for cryopreservation in -196$^{\circ}C$ liquid nitrogen were studied in Korean native Aquilegia buergeriana var. oxysepala Kitamura and A. flabellata var. pumila Kudo seeds. Aquilegia species seeds were adjusted to moisture contents between 3.2 and 9.7% by air dry treatments. Seeds were placed in paper envelopes after submerged in liquid nitrogen and rewarming in 38 $^{\circ}C$ water. Seeds moisture contents by duration of drying were identified as controlling factors in the survival of Aquilegia species seeds for cryopreservation. Aquilegia species seeds having approximate 5% moisture content were able to withstand cooling to -l96$^{\circ}C$. Undehydrated seeds of Aquilegia buergeriana var. oxysepala Kitamura after being cryopreservated in liquid nitrogen have a 10.9% of moisture content and show 52.5% in germination. But, Aquilegia buergeriana var. oxysepala Kitamura seeds dehydrated by drying for 60 min. to have 6.0% of moisture content before cryopreservation show 84.7% in germination test. Properly dehydrated seeds after being stored in liquid nitrogen showed over 60% in germination rate and also shows an uniform sprouting time,11~13 days in average. Any morphologically deformity in germinating beds has not been observed. Results from this study suggest that Aquilegia species seeds can cryopreservation in liquid nitrogen if the seed moisture content is controled by a proper amount of dehydration.

• Journal of Korean Society of Forest Science
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• v.112 no.4
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• pp.442-450
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• 2023

This study sought to determine the desiccation tolerance and storage behavior of Sarcandra glabra seeds to assist in the establishment of an ex-situ conservation strategy for the species. The basic germination characteristics of S. glabra seeds were investigated. Subsequently, the seeds were dried to various desiccation levels to allow for analysis of their germination characteristics and seed integrity. In addition, the seeds were subjected to germination tests after being stored for different durations. The initial seed moisture content following the removal of the fleshy fruit was 32.8%, and the fresh seeds maintained their seed viability even after a decrease in the seed moisture content to 4.8%, while the germination percentage was 81.0%. The germination percentage of the seeds decreased to 55.0% and 30.0% when they were desiccated to moisture contents of 2.3% and 2.2%, respectively. By contrast, when the stored seeds were desiccated, they maintained their seed viability and vigor at a moisture content of 18.6%; however, when the moisture content decreased below 5.0%, both the seed viability and vigor significantly declined and the germination percentage fell below 20.0%. Furthermore, analysis of the seed leachate revealed that the decrease in the seed viability and vigor was associated with both increased electrical conductivity and increased concentrations of inorganic compounds such as potassium and calcium. In conclusion, the findings of this study show S. glabra seeds to possess desiccation tolerance that falls somewhere between the recalcitrant and intermediate seed types, with the observed variations depending on the degree of deterioration.

• Journal of Life Science
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• v.19 no.4
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• pp.526-531
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• 2009

This study was conducted to identify the optimum condition for dehydration and storage for maintaining the seed vigor in pelleted carrot seeds. The water content of solid materials of un-pelleted seeds was 4.9% (F.W. basis), and that of pelleted seeds was 24%. When we dehydrated pelleted seeds for 3 hr at $25^{\circ}C$, $35^{\circ}C$, and $45^{\circ}C$, all seeds were dehydrated to 5% - the same level of water content as that before pelleting. Pelleted seeds did not show any significant difference in germination from un-pelleted seeds, and neither was there any significant time or germination difference between pelleted and un-pelleted seeds at the tested dehydration temperatures. However, the $T_{50}$ value of pelleted seeds increased about 3 days larger than that of un-pelleted seeds. Germination speed of pelleted seeds in which the dehydration period was prolonged at $45^{\circ}C$ was delayed compared to those prolonged at $25^{\circ}C$ or $35^{\circ}C$ for the same period. The optimum dehydration condition, which could be applied for large scale in the industry, was dehydration at $35^{\circ}C$ for 3 hr, and the optimum storage temperature which could maintain the seed performance was $5^{\circ}C$.

• Korean Journal of Agricultural Science
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• v.9 no.1
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• pp.357-370
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• 1982

Recent concern regarding price and availability of fossil fuels has spurred the interest in alternative sources for farm crop drying. Among the available options such as biomass energy, wind power, nuclear energy and solar energy etc., the increasing attention is being directed to the utilization of heat from solar energy especially for farm crop drying. Even though solar energy is dispersed over a large land area and only a relatively small amount of energy can be simply collected, the advantages of solar energy is that the energy is free, non-polluting. The study reported here was designed to help supply the informations for the development of simple and relatively inexpensive solar warehouse for farm crop drying and storage. Specifically, the objectives of this study were to determine the performance of the solar collector fabricated, to compare solar supplemented heat drying with natural air drying and to develop a simulation model of temperature in stored grain, which can be used to study the effects due to changes in ambient air temperature. For those above objectives, solar collector was fabricated from available materials. Corrugated steel galvanized sheet, painted flat black, was used as absorbers and clear 0.2mm polyethylene sheet was the cover material. The warehouse for rough rice drying and storage was constructed with concrete block, and the solar collector was used as the roof of warehouse instead of original roofing system of it. The results obtained in this study were as follows: 1. The thermal efficiency of the solar collector was average 26 percent and the overall heat transfer coefficient of the collector was approximately $25kJ/hr.m^2\;^{\circ}K$. 2. Solar heated air was sufficient to dry one cubic meter of rough rice from 23.5 to 15.0 percent in 7 days and natural air was able to dry the same amount of rough rice from 20.0 to 5 percent in l2 days. 3. Drying with solar heat reduced the required drying time to dry the same amount of rough rice into a half compared to natural air drying, but overdrying problems of the bottom layer were so severe that these problems should be thoroughly analyzed. 4. Simulation model of temperature in stored grain was developed and the results of predicted temperature agreed well with test results. 5. Based on those simulated temperature, changes in the grain-temperature were a large at the points of the wallside and the damage of the grain would be severe at the contact area of wall.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.3
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• pp.179-183
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• 2000

This study was conducted to examine the changes of contents of ATP related compounds during drying of large anchovy and storage of dried large anchovy (DLA) according to storage temperature and package method. The total content of ATP related compounds of raw large anchovy was $36.0{\mu}mole/g$ and the major ATP related compounds were consisted of IMP and hypoxanthine. The IMP content of DLA was the highest in $20^{\circ}C$ cold-air drying, and the breakdown of IMP was progressed rapidly in $60^{\circ}C$ air drying, followed by $40^{\circ}C$ air drying, sun drying, and $20^{\circ}C$ cold-air drying. During storage of DLA, ATP was not detected while ADP and AMP was detected in a very small amount, and the changes of ATP related compounds were coincided with the changes of contents of IMP, inosine and hypoxanthine. The changes of ATP related compounds with different package method did not show distinct differences, while with different storage temperature showed clear difference. The content of IMP was over $8.88{\mu}mole/g$ on 60 days at $-20^{\circ}C$, while were over $0.83 {\mu}mole/g$ and$ 0.202 {\mu}mole/g$ on 16 days at$ 5^{\circ}C$ and$ 25^{\circ}C$, respectively. These results suggest that the breakdown of IMP depends on storage temperature and frozen storage affects good quality of DLA during storage.

• Food Science and Preservation
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• v.12 no.5
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• pp.436-441
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• 2005

This study was observed the effects of drying methods on the extraction characteristics of Rubi fructus (fruits of Rubus coreanus). Extraction yields of soluble solids and total sugar were high in the Rubi fructus dried by freeze drying, followed by infrared drying and sun drying. Extraction yield of phenolic compounds and DPPH radical-scavenging activity of extracts were in the following order; the Rubi fructus dried by freeze drying, the Rubi fructus dried by infrared drying, the Rubi fructus dried by sun drying. L value was the highest in the Rubi fructus dried by freeze drying, and a and b value were lowest in the fruit dried by freeze drying. These results suggest that freeze drying has an beneficial effect to enhance the quality of Rubi fructus. Water and ethanol extractions was more effective in the extraction of soluble solids and the antioxidative components.

• Food Science and Preservation
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• v.5 no.4
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• pp.350-354
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• 1998

This paper was investigated to changes of cell components during drying for studies on the softening of jujube fruits. The contents of alcohol-insoluble material, cell wall and water-soluble material were not changed at 6 days of drying, but alcohol-insoluble materials and cell wall were decreased at 9 days of drying, however water-soluble materials were increased. Pectin and hemicellulose were not changed at 6 days of drying. Pectin and alkali-soluble hemicellulose were remarkable decreased at 9 days of drying, but acid-soluble hemicellulose was increased. Water-soluble pectin was not changed at 6 days of drying, but increased at 9 days of drying. EDTA-soluble and insoluble pectin were decreased after 6 days of drying. The non-cellulosic neutral sugars were not changed at 6 days of drying. The contents of arabinose, galactose and total neutral suger were decreased at 9 days of drying.