• The Korean Journal of Food And Nutrition
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• v.11 no.2
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• pp.179-184
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• 1998

As a way of mass process of onion, Allium cepa L., the oleoresin decompressed and concentrated is an alternative process to minimize lowering in the quality of onion during storage, to improve the original flavor and taste, and to increase variety as processing aids. This study was performed to investigate on the quality stability during storage of oleoresin. Oleoresin product was manufactured by mixing a concentration of onion juice and ethanol extract homogenously, emulsified by an additional 2% PGDR(polyglycerol condensed ricinoleate) and 1% cysteine. During 60 days storage at 5$^{\circ}C$, $25^{\circ}C$ and 4$0^{\circ}C$ the total sugar content in oleoresin product was very stable, and absorbances at 420nm as browning reaction index were 0.38, 1.53 and 3.32, respectively, addition of 1% cysteine retarded the browning reaction effectively. When oleoresin product was centrifuged(2000$\times$G, 60 minutes), the volumes of emulsion level without separation were 96.8%, 94.1% and 9.06%, respectively during 20 days, 40 days and 60 days storage at 5$^{\circ}C$, and those during 60 days storage at $25^{\circ}C$ and 4$0^{\circ}C$ were appeared to be 83.2% and 75.4%. Showing lower level as increasing storage temperature. Antioxidant indexes(AI) of soybean oil added 1% oleoresin without storage and 0.02% BHA were 1.39 and 1.72. The former showed 80.8% antioxidant activity on induction time extension effect of the latter. Antioxidant indexes of oleoresin decreased slightly as increasing storage temperature and were 1.37, 1.30 and 1.08. Total pyruvate contents were 89.9%, 79.7% and 65.2%, respectively during 60 days storage at 5$^{\circ}C$, $25^{\circ}C$ and 4$0^{\circ}C$. Rate constant, Q10 value and activation energy were 1.381~4.735 mmol/$\ell$.hr, 1.537~1.694 and 11.649 ㎉/g mole for the reduction of pyruvates in the range of storage temperatures during oleoresin storage.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.3
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• pp.275-279
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• 1984

To develop a long term storage technique of soybean germplasm, fifty lines of soybean seeds were kept in storage room controlled by air-conditioner and dehumidifier at KAERI. The storage room was kept below 25$^{\circ}C$ of temperature and 60% relative humidity. Germinability of stored seeds was evaluated at every three or six months. On the other hand, the newly harvested seeds of the lines were accerelated aging at 40$^{\circ}C$ and 90% of relative humidity, and compared with non-accerelated seeds. The average germinability at the starting time of storage was 97% but the germinability was decreased to 62% at 42 months after storage in the storage room. The germinability seemed to be affected by seed size and seed coat color. The germinability of small seed lot tended to be higher than that of large seed lot, and the germination response in longer term of storage was greater than those of shorter term of storage. The accerelated aging test for 7 days proved to be a useful technique to pretest germinability of soybean seeds for assaying the relative storage potential.

• Journal of Korean Society on Water Environment
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• v.33 no.2
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• pp.187-196
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• 2017

To ensure hygienic safety of drinking water in a water storage tank, the concentrations of residual chlorine should be above a certain regulation level. In this study, we conducted model simulations to investigate the effects of temperature on residual chlorine in water storage tank conditions typically used in Seoul. For this, values of model parameters (decomposition rate constant, sorption coefficient, and evaporation mass transfer coefficient) were experimentally determined from laboratory experiments. The model simulations under continuous flow conditions showed that the residual chlorine concentrations were satisfied the water quality standard level (0.1 mg/L) at all the temperature conditions ($5^{\circ}C$, $10^{\circ}C$, $15^{\circ}C$, $20^{\circ}C$ and $25^{\circ}C$). Meanwhile, when the tanks had a no flow condition (i.e., no tap-water influent due to a sudden shut-down), the concentrations became lower than the regulatory level after certain periods. The findings from this modeling works simulating Seoul's water storage tanks suggested disappearance rate of residual chlorine could be reduced through the tanks design optimization with maintenance of low water temperature, minimization of air flow and volume, suppression of dispersion and the use of wall materials with low sorption ability.

• 정보저장시스템학회:학술대회논문집
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• 2005.10a
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• pp.83-87
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• 2005

Data storage related with writing and retrieving requires high storage capacity, fast transfer rate and less access time in. Today any data storage system can not satisfy these conditions, but holographic data storage system can perform faster data transfer rate because it is a page oriented memory system using volume hologram in writing and retrieving data. System architecture without mechanical actuating pare is possible, so fast data transfer rate and high storage capacity about 1Tb/cm3 can be realized. In this paper, to correct errors of binary data stored in holographic digital data storage system, find cluster centers using clustering algorithm and reduce intensities of pixels around centers. We archive the procedure by two algorithms of C-mean and subtractive clustering, and compare the results of the two algorithms. By using proper clustering algorithm, the intensity profile of data page will be uniform and the better data storage system can be realized.

• Food Science and Preservation
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• v.11 no.2
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• pp.135-141
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• 2004

To examine the quality changes of tomato and plum fruits during storage under various storage conditions, the rate of weight loss, pH change, titratable acidity, Hunter a value, firmness, and anthocyanin content were determined during storage. Tomato and plum fruits were stored at 4$^{\circ}C$ and 25$^{\circ}C$. Tomato fruits were packaged with high density polyethylene film (HDPE) and polyvinylidene chloride film (PVDC), and plum fruits were packaged with HDPE. Tomato fruits packaged with PVDC and plum fruits packaged with HDPE at 4$^{\circ}C$ were the most desirable in terms of weight loss. Titratable acidity of tomato fruits decreased with increasing storage time regardless of temperature and packaging method. Hunter a value of tomato fruits stored at 25$^{\circ}C$ increased regardless of packaging method, while it was not changed for tomato fruits stored at 4$^{\circ}C$. Firmness of plum fruits stored at 25$^{\circ}C$ significantly decreased during storage and anthocyanin content increased. Microbial numbers of tomato fruits increased during storage, but its rate was retarded during storage when tomato fruits were packaged with HDPE and stored at 4$^{\circ}C$. These results suggest that cold chain system and appropriate packaging could maintain the quality and prolong the shelf life of fresh produce.

• Horticultural Science & Technology
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• v.31 no.2
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• pp.194-202
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• 2013

The aim of this work was to study the changes in fruit quality and antioxidant activity depending on ripening levels, storage temperature and storage periods in two strawberry cultivars (Fragaria ${\times}$ ananassa cvs. Daewang and Seolhyang). Fully ripe strawberry fruits (100% colored fruits) and unripe strawberry fruits (50% colored fruits) were harvested and then stored at $4^{\circ}C$ and $15^{\circ}C$ for 10 days, respectively. Hardness, phytochemicals, sugars, organic acids and antioxidant activity of strawberry fruits were measured after storage for 5 and 10 days, respectively. When fruit hardness was compared between the two cultivars, 'Daewang' showed a greater degree of fruit hardness than 'Seolhyang'. 'Daewang' also showed higher amounts of phenolic compounds and sucrose than 'Seolhyang'. In contrary to this, 'Daewang' was shown to contain lower amounts of anthocyanin and fructose than 'Seolhyang'. However, antioxidant activities of both cultivars were almost identical. When the effects of storage temperature were examined on fruit hardness, fruits stored at $4^{\circ}C$ showed a higher degree of hardness than those stored at $15^{\circ}C$. During the period of fruit storage at $4^{\circ}C$ or $15^{\circ}C$, both cultivars showed marked decline in the contents of phenolic compounds as well as sucrose. Contrastingly, they showed higher amounts of anthocyanin and glucose after 10 days of storage. On the other hand, the contents of organic acids in strawberry fruits were influenced only by the period of storage, not depending on cultivars or temperatures. Antioxidant activities of fully ripe fruits declined remarkably after 10 days of storage, as compared to unripe fruits which showed a minor decrease or increase. When fully ripe fruits of both cultivars were stored at different temperatures, those stored at $15^{\circ}C$ showed a significant decrease in the antioxidant activity as compared to those stored at $4^{\circ}C$. However, changes of antioxidant activity in unripe fruits were minor. These observations in order to supply high quality strawberry suggest that fully ripe strawberry fruits should be harvested for the short-term storage and the appropriate ripe level fruit should be harvested for the long-term storage. Storage temperature is appropriate at $4^{\circ}C$.

• Food Science and Preservation
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• v.18 no.4
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• pp.467-474
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• 2011

As a serial study to investigate optimum storing temperature of fresh ginseng (Panax ginseng C. A. Meyer), the respiration rate and internal quality of the ginseng was compared during storage for 16 weeks at $-3^{\circ}C$, $-1.5^{\circ}C$ and $0^{\circ}C$. At initial storage period, respiration rate of fresh ginseng was lower at lower temperature, but thereafter it was negligible. Changes in the firmness of fresh ginseng were not significantly different by the storage temperature. The soluble solids content in fresh ginseng was rapidly increased in the early part of storage, and fresh ginseng stored at a lower temperature had a lower content of soluble solids. The iodine-stained color for starch of the main root was rapidly changed for 4 weeks, and L value of the color was the highest in the center, followed by the cambium and the cortex. pH were a little change depending upon the storage temperature, and as a whole, pH was the lowest at $-3^{\circ}C$, followed by $-1.5^{\circ}C$ and $0^{\circ}C$. Although the content of crude saponin tended to somewhat increased as the storage period passed, the effect of storage temperature on changes in the content was not clear. In the sensory evaluation of 'unique flavor' of fresh ginseng using 5 point scale, higher than 3 point was marked for 8 weeks at $-3^{\circ}C$, 14 weeks at $-1.5^{\circ}C$ and 16 weeks at $-0^{\circ}C$ during storage (p < 0.05).

• Korean journal of food and cookery science
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• v.27 no.1
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• pp.63-73
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• 2011

Cabbage (Baechu) Kimchi in its truncated form was placed in four different packing materials, Ny/PE/LLDP, OPP/AL/PE, PP and PET, and quality changes were observed during storage. Changes in pH and total acidity showed an x-shaped cross-curve as pH decreased and total acidity increased during storage. PP tray showed the slowest change at $5^{\circ}C$ with time. The pH was initially 6.25, but decreased to 4.12~4.16 at 20 days, and total acidity showed a 4 to 4.8-fold increase after 20 days of storage compared to the initial value. During storage at $5^{\circ}C$, total bacterial count and lactic acid bacterial count rapidly increased after 4 days. The total bacterial quantity decreased after a period of time and there were differences according to packaging material; OPP/AL/PE packaging showed the most dramatic decrease. Change in microbial count mostly followed a similar pattern to that of total acidity for all packaging materials. Changes in the color of Kimchi liquid, when examined by color index in $L{\cdot}b$/a form, rapidly decreased over time, similar to pH. Small Ny/PE/PP and OPP/AL/PE packages of Kimchi were examined for changes in free volume inside the packaging. After 13 days of storage at $5^{\circ}C$, the volume was 243 mL, but storage at $20^{\circ}C$ resulted in a volume of 372 mL, a more than 1.5-fold increase in free volume. There were changes in the quality characteristics of small package Kimchi according to storage temperature and packaging material, and large changes in pH, total acidity, and microbial count were evident upon storage at $5^{\circ}C$ for 8 days, which was the optimum palatability period. Mostly, PP treatment showed the slowest quality changes upon storage at $5^{\circ}C$. However, due to small package Kimchi's fast consumption system, the appropriate choice of packaging material must consider the product's turnover ratio. Further, the varieties of small package Kimchi should be diversified according to different consumer preferences by offering Kimchi with different maturity levels. Further, since the leading consumer base ranges in age from the teens to thirties, the development of various products targeting such consumers is necessary.

• Korean Journal of Food Science and Technology
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• v.21 no.2
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• pp.283-288
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• 1989

The effect of storage temperature on the quality characteristics of meat sausage was investigated. Thus, the quality characteristic changes of meat sausage were discussed through physico-chemical and microbiological analysis. The results were summarized as follows; Volatile basic nitrogen(VBN) was increased more rapidly at $40^{\circ}C$ than at $10^{\circ}C$, $20^{\circ}C$ and fluctuating temperature $(10/40^{\circ}C)$. In physico-chemical analysis of meat sausage, the values of VBN , viable cell counts were increased with increase of temperature during storage, while thiobarbituric acid(TBA) values were fluctuated during storage as a whole. Water activity(Aw) and moisture contents showed a little change according to storage temperature, but sausage color was darkened as storage time goes by as a whole, the shelf-life was predicted above 40 days at $10^{\circ}C$, below 40 days at $20^{\circ}C$, below 30 days at $40^{\circ}C$ and about 20 days fluctuating temperature $(10/40^{\circ}C)$, respectively on the basis of slime formation in sensory evaluation.

• Journal of the Korean Applied Science and Technology
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• v.34 no.2
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• pp.410-417
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• 2017

The physical properties of perilla leaves cultivated in Geumsan province were analyzed according storage conditions. The a/b values of perilla leaves increased with increasing storage period. Electronic nose composed of 12 different metal oxide sensors was used to differentiate flavors of perilla leaves. Sensitivities(delta $R_{gas}/R_{air}$) of sensors from electronic nose were obtained by principal compound analysis(PCA). Proportion of the first principal component was 93.07% at $25^{\circ}C$ and 97.81% at $4^{\circ}C$, respectively. In our result, flavor patterns of perilla leaves can be differentiated according to the storage temperature.