• Journal of the Korean Wood Science and Technology
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• v.45 no.3
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• pp.335-342
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• 2017

This study was carried out to explore a new application of the by-products sawdust, formed during sawing and mandarin peels which are agricultural by-products. The boards were manufactured by mixing the sawdust and mandarin peels at different mixing ratio and density. The boards were then converted to ceramics by various percentage of resin impregnation and at different carbonization temperatures. As the percentage of resin impregnation increased, the weight loss was decreased; on the other hand, density, linear shrinkage and thickness shrinkage increased. As the carbonization temperature increased, the weight loss was increased and linear thickness shrinkage increased to $1000^{\circ}C$ and the subsequent increase was insufficient. As the percentage of mandarin peels addition increased, the weight loss, linear shrinkage and thickness shrinkage was decreased.

• Tunnel and Underground Space
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• v.21 no.2
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• pp.145-150
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• 2011

Variations of physical properties such as weight loss rate, wave velocity and uniaxial compressive strength after performing freeze-thaw cyclic test were measured in order to define weathering characteristics of sandstone and andesite. Weight change in specimens of the two rocks decreased with increasing the repetition number of freeze-thaw cyclic test. In particular, weight loss of andesite specimens was very irregular. P-wave velocity of sandstone specimens decreased more than 5%. On the other hand, P-wave velocity of andesite specimens do not vary up to 500 cycles and decreased more than 5% after 1000 cycles. This implies that the sandstone are easily weakened and loosened by weathering processes, while the andesite are relatively strong. In addition, the wave velocity changes of the andesite specimens coincident with the weight change. Uniaxial compressive strengths of the sandstone specimens slightly decreased at the early stage of the freezing-thawing cyclic test, then tended to be irregular after 64 cycles. In conclusion, the rock specimens showed smaller weight loss, less had lower strength reduction rate.

• Food Science and Preservation
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• v.9 no.4
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• pp.362-368
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• 2002

Physicochemical properties of garlic bulb during storage with different cutting treatments were estimated. Garlic harvested in early June was used in this experiments. Various physicochemical factors of garlic bulb such as weight loss rate, rotten rate, sprouting rate, moisture content, reducing sugar content and total pyruvate content were investigated. Bulbs with roots, bulb without roots and bulb with stem length of l cm, 3 cm, 5 cm were stored at 2$\^{C}$ for eight months. The weight loss increased sharply after 8 months for all treatments. Weight loss occurred most severely in treated garlics with bulbs with 5 cm stem length and progressed steadily at low rates in bulbs with 1 cm stem length. Also, less decay and internal sprouting were observed in bulbs with 1 cm stem length. Cutting treatments of roots were not significant for internal sprouting. Incidence of other chemical properties of bulbs, contents of total sugar, reducing sugar and pyruvic acid were not significant statistically. Moisture contents of treated garlics was remarkably reduced in longer leaving stems. As a result, top-clipped leaving stems fur long, seemed to have a beneficial effect on physicochemical properties of garlic stored at 2$\^{C}$ for 8 months possibly due to reduced weight loss, rotten decaying and sprouting rates. Utilization of such results in the processing industry can be effective.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.119.2-120
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• 2003

신선편이 채소류의 유통 중 품질변화를 조사하고자 대형 할인 매장에서 시판중인 8종의 포장된 제품을 구입하여 4$^{\circ}C$에서 냉장저장하면서 변화를 조사하였다. 선정 품목은 양상추, 양배추, 치커리, 버섯(양송이), 연근, 우엉, 도라지, 마늘로서 총 8가지 채소류를 대상으로 하였으며, 각 시료에 따라 엽채류는 2일, 버섯, 우엉, 도라지는 3일, 마늘은 4일, 연근은 5일 간격으로 다음의 항목을 조사하였다. 중량감소율, 경도, 가용성 고형분, pH를 측정하였으며, 색의 변화는 Hunter ‘a’, ‘b’ 및 ‘L’값으로 나타내었으며 표면의 갈변도를 기계적으로 측정하기 어려운 경우 마쇄 후 여액의 흡광도(420nm)로 측정하여 나타내었다. 이와 함께 포장지 내부의 기체조성 변화 측정을 통해 호흡특성을 함께 조사하였다. 중량감소율의 경우 모든 시료가 현저히 증가하였으나 진공포장된 연근, 우엉의 경우 중량감소율이 낮았으며, 특히 우엉은 호흡률이 높아 저장 6일째에 진공이 해제되었다. 마늘과 우엉의 pH는 감소하였고, 나머지는 전체적으로 증가하는 경향을 나타내었다. 특히 엽채류와 도라지의 O.D value의 증가와 버섯의 L value 감소가 현저하여 이 품목에서 갈변이 빠르게 진행됨을 알 수 있었다.

• Journal of Animal Science and Technology
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• v.54 no.1
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• pp.35-41
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• 2012

The aim of this study was to offer information about appropriate processing method for dry cured-ham with controlled ripening condition. In this study, three different treatments were performed: High salt group (HS), 18 hams were salted with 70 g $kg^{-1}$ salt (w/w) Middle salt group (MS), 18 hams were salted with 50 g $kg^{-1}$ salt Low salt group (LS), 18 hams were salted with 30 g $kg^{-1}$ salt. Also three drying periods were applied (180 days, 270 days and 360 days). The weight loss in HS was higher (5.62%) on curing step and in LS was higher (12.35%) on post-salting step compared to other groups. On fermentation stage, weight loss of HS was higher than that of LS (p<0.05). Weight loss on drying was increased as the drying period passes (p<0.05). Moisture contents were significantly (p<0.05) decreased and fat contents were significantly (p<0.05) increased in all treatment groups as drying period increased. The different drying periods affected fatty acid compositions on all salting levels; saturated fatty acid contents were increased (p<0.05) with more drying, whereas unsaturated fatty acid contents were decreased (p<0.05) as drying period increased.

• Food Science and Preservation
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• v.14 no.1
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• pp.42-46
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• 2007

To investigate the effects of hot water treatment and modified atmosphere packaging (MAP), compared with non-packaging, of 'Fuji' apples during 18 weeks of storage at $0^{\circ}C$, apple weight loss, firmness, titratable acidity, total ascorbic acid and sensory characteristics were measured After 18 week of storage, the weight loss of MAP-treated apples was 1%, while untreated controls lost 22% of weight Weight loss reduction film packaging was more effective than that afforded by hot water treatment. The firmness reductions in control apples, those receiving hot water treatment those receiving packaging only, and those receiving both hot water treatment and packaging, were 37%, 22%, 10% and 6%, respectively. The titratable acidity was 40% in control apples and respectively, 37%, 32% and 27% in the three groups mentioned above. The total ascorbic acid contentuntreated control apples decreased by 70% after 18 weeks of storage. The total ascorbic acid contentof apples receiving both hot water use of both packagingand hot water treatment to preserve 'Fuji' apple quality.

• Journal of the Korean Wood Science and Technology
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• v.42 no.3
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• pp.251-257
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• 2014

For new use development of miscanthus sinensis var. purpurascens, which investigated properties of ceramics made from different carbonization temperature ($600{\sim}1,200^{\circ}C$) and percentage of resin impregnation(30~60%) using a mincanthus board. As the carbonization temperature increased, the density, thickness shrinkage, linear shrinkage, weight loss were increased. As the percentage of resin impregnation increased, the density, linear shrinkage and weight loss were increased. On the other hand, thickness shrinkage decreased.

• Korean Journal of Food Science and Technology
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• v.22 no.4
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• pp.445-450
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• 1990

Changes in weight, volume and density of petiole tissue of Chinese cabbage during salting and blanching were investigated. Rapid changes in mass and volume occurred within 4 hours during salting in 5% salt solution and the changes were nearly completed after 8h. After salting, the reduction of mass and volume ranged between $22{\sim}27%\;and\;22{\sim}35%$, respectively. Average density of the sample was found to be 0.88g/ml, and increased to 1.020g/ml after salting. Air content of the sample ranged from 0.093 to 0.120ml/ml cabbage, and about 70% of the initial content was expelled from the tissue by salting. The changes of physical properties of the cabbage during steam blanching were similar to those during salting, but their relative values were smaller. A linearization model for physical changes during salting and blanching was proposed.

• Applied Biological Chemistry
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• v.40 no.2
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• pp.117-122
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• 1997

The conditions of cold storage of Citrus unshiu Marc. var. miyagawa produced in Cheju were investigated. Compared to the citrus fruits stored at room temperature, the content of soluble solids, total sugar, vitamin C and specific gravity decreased slightly on the fruits stored at $4^{\circ}C$ and 87% relative humidity. Decay ratio and weight loss were below 10% on keeping freshness relatively till late of March during cold storage. Weight loss, decrease of firmness and soluble solids occured gradually during cold storage. Nevertheless seal-packaging with 0.02 mm LDPE film or wax-coating of citrus fruits were effective on weight loss and appearance, decay ratio increased for long-term storage. It was needed to control humidity in cold chamber for preventing from decay and weight loss. Edible part ratio was decreased gradually by respiration, and peel and tissue of fruits were softened slightly by 60 days of cold storage. Decay ratio and weight loss of full-ripened citrus fruits were little during the storage for 100 days, compared to the fruits harvested early. Appearance and taste of citrus fruits stored for 4 month were good relatively, but decay occured rapidly on seal-packaging fruits putting out of cold room for a few days. Because of the difficulty of long-term storage for early variety of Citrus unshiu, the conditions and periods of cold storage would be determined after considering the physicochemical properties of fruits.

• 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.205.1-205
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• 2003

본 연구는 국내 유통쌀의 포장재로 널리 이용되고 있는 지대포장재와 합성수지계열의 PE 및 AL 포장재의 저장기간에 따른 품질특성을 구명하고, 포장재의 투습도 5~700g/$m^2$범위의 4수준에 대하여 함수율, 중량 및 지방산가의 변화를 측정하여 포장재의 적정 투습도를 결정하는데 목적이 있다. 지대, PE 및 AL포장재의 저장 4주 후의 중량은 7.8, 0.1 및 1.5%감소하였으며, 함수율은 지대포장의 경우 3.7%(w.b.)감소하였다. 지방산가는 저장 4주 후에 지대포장은 9.4, PE포장재는 42.0, AL포장재는 16.8(mg KOH/100g)로 나타났다. 저장온도 20 및 3$0^{\circ}C$에서의 포장재 투습도에 따른 중량, 함수율 및 지방산가의 변화를 고려했을 때 130~210g/$m^2$이 적정한 것으로 나타났다.