• Title/Summary/Keyword: Low temperature storage condition

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A Study on the Properties of Dicalcium Phosphate Dihydrate According to the Manufacturing Condition (제이인산(第二燐酸)칼슘의 제조조건(製造條件)에 따른 성상(性狀) 연구(硏究))

  • Lah, Woon-Lyong;An, Kyung-Ran;Han, Kwan-Sup;Lee, Gye-Joo
    • Journal of Pharmaceutical Investigation
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    • v.6 no.1
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    • pp.26-32
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    • 1976
  • Dicalcium phosphate dihydrate (DCPD) is the most widely-used dentifrice abrasive in non-therapeutic tooth-paste requiring, low abrasive level, high stability and excellent compatibility with other formulation ingredients. One of the difficulties encountered in the use of this material in tooth-paste is that unless storage of the product is maintained at a relative low temperature there is a distinct tendency to lose water of crystallization. Another difficulty which has been encountered is that there is a tendency for the product to become lumpy. Various means have been proposed for increasing the stability and overcoming the lumping tendency, most of which means comprise the addition of stabilizing agent. But there is not any report about the relationships between the mechanism of dehydration, physical properties, structure and manufacturing condition. In this experiment, DCPD were manufactured by methods of Moss' patent, its two varied and J.P.VIII, these were studied by means of stability test, IR spectra, and DTA. According to the manufacturing conditions, DCPD has different physical properties and structures, i. e., monoclinic system of low drying temperature, triclinic system of high drying temperature. Dehydration of DCPD may be supposed one step debydration at about $100^{\circ}$ and it finaly converts to ${\gamma}-pyrophosphate$ at about $465^{\circ}$ and if the drying temperature is high it becomes DCP anhydrous. DCPD made by Moss' patent is thought of the best polishing agent of tooth-paste.

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Study on shipment time of low-temperature stored apple (저온저장 사과의 출하시기에 대한 실태조사 연구)

  • Yu, Chang-Hwan;Kim, Yun-Ho
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.7
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    • pp.554-564
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    • 2017
  • The purpose of this study is to assist farmers in determining the optimal time for the shipment of stored apples by investigating the market trends, storage status and release dates of low-temperature stored apples. We surveyed 300 apple cultivation farms in Daegu, Gyeongbuk Province, which is the main producer of apples, and examined the cultivars, cultivation areas, storage conditions, and shipment status of apples. The main results are as follows: the proportion of apples cultivatedat different ripening times was surveyed. According to the results, the proportions of early, middle and late varieties were 78.3%, 63.7% and 96.0%, respectively. Also, 48.7% of the farm households surveyed had cold storage facilities. The average storage cost per apple box(15kg) was 978.3 won for self-storage and 1,771.8 won for consignment storage. For the six(6) months between November and April, the proportion of shipped apples was 91.6% of the total stored apples. The (average total?)annual apple shipment, including apples stored in general storage warehouses, was 744.4 boxes. The (average total?) annual shipment of cold storage apples was 616 boxes. The stored apples were mainly shipped to 'wholesale markets', which have the highest sales share, followed by 'production site collectors' and then 'supermarkets'. The most common shipping method of the apples was by general trucks, followed by low-temperature trucks, and finally by delivery services. The analysis of the factors influencing the decision to release apples by period showed that it was affected by the storage cost, loss rate, and customary shipping in the off-season(from May to August). On the other hand, in the general release season(from November to April), the statistically significant decision factors for the release of apples were the future expected price, storage cost and decision of the leading farmer groups. For farmers with a high share of general shipment, the deciding factors for the release of apples were the future expected price, storage cost, high income expectation, and decision by leading farmers.

Quality Change and Weight Loss of Fresh Ginseng Individually Packaged in a Soft Film According to its Storage Condition (연포장재 필름으로 개별포장한 수삼의 저장조건에 따른 외관품질 변화 및 개체무게 감소)

  • 손현주;김은희;이성계;노길봉
    • Journal of Ginseng Research
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    • v.25 no.3
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    • pp.122-126
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    • 2001
  • Fresh ginseng was washed with water and packaged individually in a soft film bag (ONY/LDPE/L-LDPE;200${\times}$300mm, 90$\mu\textrm{m}$), then stored at 25$^{\circ}C$, 10$^{\circ}C$, or 4$^{\circ}C$ to investigate quality and weight changes of the packaged fresh ginseng according to its storage time. Softening was the major phenomenon which influenced on the quality of the packaged fresh ginseng while spoilage and color-change were relatively minor phenomena. There were very good correlations not only between the quality change rate constant and the storage temperature but between the weight change rate constant and the storage temperature. This result suggests that the shelf-life and the weight loss of the packaged fresh ginseng being store at low temperature can be estimated by an accelaerated sotrage test.

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Oxidative Stability of DHA Added Mayonnaise (DHA를 첨가한 마요네즈의 산화안정성)

  • Kim, Jae-Wook;Shim, Joong-Hwan;Kim, Jong-Soo;Han, Seung-Su;Yoo, Moo-Yeong;Hur, Jong-Wha
    • Korean Journal of Food Science and Technology
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    • v.28 no.1
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    • pp.179-183
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    • 1996
  • The objective of this study was to investigate the difference of oxidative stability between DHA (docosahexaenoic acid) added and not added commercial mayonnaise, and then to find out stable condition for maintaining the quality of DHA added mayonnaise. During the storage at room temperature $(25^{\circ}C{\pm}1^{\circ}C)$, it showed that DHA added commercial mayonnaise was more sensitive to oxidation than DHA not added commercial mayonnaise. And sensory quality of DHA added commercial mayonnaise decreased drastically after 5 months from the production date of mayonnaise. During the storage at low temperature $(4^{\circ}C{\pm}1^{\circ}C)$, DHA added mayonnaise was also more sensitive to oxidation than DHA not added mayonnaise, but it showed no apparent and sensory problem with both samples during 8 months of cold storage test periods. In considering the distribution condition of mayonnaise in the country, it was suggested that shelf-life of the DHA added commercial mayonnaise should be shortened 2 or 3 months than that of the DHA not added commercial mayonnaise.

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Storage of Pollen Biofactory for in vitro Growth and rProtein Synthesis (기내배양과 재조합 단백질 생산을 위한 화분 Biofactory의 저장기술의 개발)

  • 박희성;고재철
    • KSBB Journal
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    • v.19 no.3
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    • pp.174-177
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    • 2004
  • A method of collection and long-term storage of viable lily (Lilium longiflorum) pollen grains were developed for their in vitro growth and transformation in consistency. Petroleum ether, n-heptane, cyclohexane and benzene, as pollen collection medium, were determined less toxic to pollen growth in vitro than others tested. Pollen grains, however, lost their growth activity if stored in these solvents more than a week, So, a serial performance, that is, pollen grain collection in these solvents, air-drying and immediate transfer to low temperature condition was determined desirable for keeping the viability much longer. Pollen grains from this storage showed a successful transformation in vitro with a cDNA encoding tissue plasminogen activator (TPA) protein using Agrobacterium via vacuum infiltration according to western blotting analysis.

Optimization of Glass Micro Molding Process for Glass Microlens Arrays (유리 마이크로 렌즈 어레이 성형을 위한 유리 마이크로 성형 공정 최적화)

  • Bae, Hyung-Dae;Choi, Min-Seok;Kang, Shin-Ill
    • Transactions of the Society of Information Storage Systems
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    • v.2 no.4
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    • pp.236-239
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    • 2006
  • Glass micro molding process is the most suitable process for fabricating high precision glass microlens amy at low cost. A new glass micro molding process was proposed. Tungsten carbide mold was fabricated by imprinting and sintering process to overcome the difficulties of the conventional process. In the glass micro molding process, process conditions such as processing temperature and compression force were changed. Geometrical properties of the replicated glass microlens array were measured and compared at variety process conditions. The condition of glass micro molding process was optimized. The experimental result showed that developed process was effective to produce a glass microlens array.

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Effects of Storage Conditions on Rancidity of Perilla and Sesame Seed Oils (저장조건(貯藏條件)이 들깨유(油) 및 참깨유(油)의 산패도(酸敗度)에 미치는 영향(影響))

  • Kim, Hye-Kyung;Lee, Yang-Cha;Lee, Ki-Yull
    • Journal of Nutrition and Health
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    • v.12 no.1
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    • pp.51-58
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    • 1979
  • It is a general trend everywhere that the uses of vegetable oils are increasing due to the fact that they are effective in curing and preventing symptoms of high blood pressure and various heart failure conditions. At the same time the concept that oxidative rancidity is caused by the oxidation of unsaturated fatty acid moieties whose subsequent decomposition gives rise to various undesirable, sometimes toxic compounds is now well accepted. Linolenic acid (C, 18:3) is one of highly unsaturated and readily oxidizable fatty acid. The content of this essential polyunsaturated fatty acid in perilla seed oil (PSO) was found to be as high as 48% while only 1.5% in sesame seed oil (SSO). In this experiment the oxidative stability of PSO was compared with that of SSO. The experimental test group were as follows: A) Stored at different temperatures, namely $4^{\circ}C,\;30^{\circ}C,$ and $60^{\circ}C,$ B) Stored at room temperature $(20{\pm}5^{\circ}C)$ ; a. protected from sunlight and air, b. exposed to air without sunlight c. exposed to sunlight but protected front air, d. completely exposed to both air and sunlight. The following results were obtained; 1) It was found to be most stable against oxidation to store both PSO and SSO under the low temperature $(4^{\circ}C)$ condition. According to P.V. measurements it was found to be safe to keep both oils up to $30^{\circ}C$ for at least 8 weeks. When exposed to air, sunlight and high temperature $(60^{\circ}C)$, P.V. of PSO reached there peak values, which were much higher than those of SSO. This explains much of its instability as compared to SSO against oxidation. 2) The effect of high temperature $(60^{\circ}C)$ on A.V. was found to be more striking than those of all the other storage conditions. The condition of refrigeration was most effective in keeping A.V. low for both oils as was the case in P.V. 3) For both oils, I.V. decreased throughout the experimental period (8 weeks). The range of decrement was larger for PSO than SSO. 4) There was no significant change in the compositions of fatty acids of SSO caused by various experimental storage conditions. But for PSO the compositions of stearic, oleic and linoleic acid were decreased, whereas linolenic acid was increased proportionally.

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Variation of Fresh Shoot Quality by Storage Temperature after Harvesting in Local Strain of Sedum sarmentosum (돌나물 수집계통의 수확후 저장온도에 따른 품질변이)

  • Kim, Hyo-Jin;Bae, Jong-Hyang;Lee, Seung-Yeob
    • Journal of Bio-Environment Control
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    • v.16 no.3
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    • pp.240-246
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    • 2007
  • To evaluated the effect of low temperature storage on quality of fresh shoot of Sedum sermentosum, weight loss, Hunter L, a and b value, chlorophyll, water content, and general appearance were investigated during storage at 20, 10, and $5^{\circ}C$. Just after harvesting, fresh shoots ($10{\pm}2cm$ length) were stored with wrap film (linear LDPE)-packaged condition using the Styrofoam dish ($20{\times}10cm$, which 40 fresh shoots per dish). The fresh weight of 40 shoots was gradually decreased according to days after storage and higher storage temperature. The weight loss of fresh shoots showed significant difference (8.7-25.3%) between just before storage and 10 days after storage, and the degree of weight loss was more severer in higher storage temperature. Wanju local strain showed the lowest weight loss, and the most severe case was Pohang local strain. SPAD value related to chlorophyll content was rapidly decreased after 4 and 6 days at 20 and $10^{\circ}C$ storage, respectively. It was slowly decreased according to days after storage at $5^{\circ}C$. Yellowish color in bottom leaves of shoot appeared after 4, 6 and 8 days at 20, 10, and $5^{\circ}C$ storages, respectively. Hunter L and a values were gradually increased after storage, and it showed significant difference between just before storage and 10 days after storage. The total rate of discoloration over 50% or decay shoot was largely increased as higher temperature. It was significantly correlated to the water content of fresh shoot among local strains $(P{\leq}0.01)$. The freshness of shoot after storage was maintained in order of Wanji, Gunsan, Wando and Pohang local strain. The results indicated that the freshness was maintained for 8 days after $5^{\circ}C$ storage, when the fresh shoot was stored with wrap film-packaged condition.

Effect of Freeze Injury by Weather on Quality of 'Fuyu' Sweet Persimmon at Harvest and Subsequent Storage (수확기 동상해 피해가 '부유' 단감의 저장 품질에 미치는 영향)

  • Jo, Yun Hee;Choi, Seong-Tae;Kim, Seong-Cheol;Kim, Eun-Gyeong;Hwang, Yeon-Hyeon;Kim, Eun-Seok;Ahn, Gwang-Hwan
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.21 no.2
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    • pp.73-78
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    • 2015
  • Persimmons on the trees are often exposed to weather condition of cold temperature before harvest, which affects the fruit quality at harvest time and later storage. This study investigated the effect of the harvest season temperature on the storage quality of 'Fuyu' sweet persimmons. Monitoring the temperature changes in the orchard showed five times of cold temperature below the freezing temperature of persimmon, $-2.1^{\circ}C$, in the harvesting period between mid October and mid November with the lowest being as low as $-5.4^{\circ}C$. Among three different harvestings, the tertiary one at mid November showed decreased 'L' value and consistently high 'a' value of color index and high reduction in hardness during 150 days storage of fruits at $0^{\circ}C$ showing freeze-injured symptoms, compared to the first one at mid October and the second one at early November. The fruits of first harvest maintained consistently hard texture with increased 'a' color value probably due to postharvest ripening. The tertiary harvest exhibited increase in fructose and glucose contents and decrease in sucrose of the fruits, being very different from the first and secondary harvests which maintained constant level of all three free sugars. Mid November with possible sudden temperature drop is unsuitable period for harvesting sweet persimmons in the quality at harvest and later storage, and thus the harvest should be designed to be done before that time.

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Manufacturing and Quality Characteristics of Low Calori Kimchi Noodle (저열량 김치국수의 제조 및 품질특성)

  • Kim, Hyong-Yol;Lim, Heung-Youl
    • Journal of the Korean Society of Food Culture
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    • v.20 no.3
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    • pp.315-322
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    • 2005
  • Kimchi noodle have a original taste and characteristics. This noodle was used for sour kimchi, kimchi taste powder, red bean fiber and emulsified oil etc. with RS(resistant starch) premix as blended wheat flour mixed to resistant starch. For manufacturing process of this kimchi mixed dry noodle, suitable kimchi of $pH3.70{\sim}3.80$ was required storage period during $4{\sim}5days$ at room temperature. At this point, the suitable treating amount of sour kimchi was about 20%(w/w) level. Manufacturing of kimchi noodle could be at the suitable manufacturing condition from use of kimchi taste powder and red bean fiber etc. Calori of this kimchi noodle was 308.17Kcal/100g as low level than wheat flour noodle as 355.82Kcal/100g, decreasing effect of calori was about 13.39%. This kimchi noodle had a characteristic sour and hot taste, that wasn't required the special seasoning and/or soup at this result.