• Food Science and Preservation
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• v.4 no.3
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• pp.343-349
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• 1997

The rheological Voperties of biopolymers produced by Bacilli sp. K-1 and its mutant strains(KM-21, KM-83) were studied at the temperature ranges with 20∼80$^{\circ}C$, at the concenration of 2∼6%, at the pH ranges from 3.0 to 9.0 and at the shear rate of 9.3-930sec-1 The apparent viscosity of biopolymers was decreased with increasing shear rate, and thereby biopolymers showed pseudoplastic characteristics. It was found that the apparent viscosity models respected 19 temperature, concentration and both temperature and concentration were expressed by Arrhenius Model, Exponential Model and combined of the above two Models. Therefore, the apparent viscosity could be predictable by Arrhenius and Exponential Models with high R2.

• Food Science and Preservation
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• v.4 no.3
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• pp.237-243
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• 1997

Numerous variables affect product cooling rate of pressure cooling system for fruits and vegetables. These include carton vent area, initial and desired final product temperature, flow rate and temperature of the cooling air, product size, shape and thermal properties and product configuration(whether in bulk or packed in shipping cartons). This study was carried out to determine the influence of each of these variables as they affect cooling time. The opening ratio and number of the vent hole were recomended as 4∼10% and 2∼4ea., respectively, for a minimum alt flow resistance and for a uniform air flow pattern. In the cooling experiment for tomatoes and mandarins, optimum air flow rate was 0.04 m3/min.kg in terms of energy saving. The cooling air temperature should be about 2$^{\circ}C$ less than the desired final product temperature for reducing cooling time.

• Journal of Biosystems Engineering
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• v.41 no.3
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• pp.184-192
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• 2016

Purpose: To solve the decay phenomenon of Hanfu apples that occurs during storage and obtain the best environmental parameters for preserving Hanfu apples using Fluent. Methods: Preservation storage was designed by analyzing the characteristics of Hanfu-apple storage and the natural environment in northeast China. The boundary conditions and simulation of a preservation model were established. Results: Compared with the initial values, the hardness decreased by $1.95kg/cm^2$, the sugar-acid ratio decreased by 20.43, and weight-loss rate was 3.98%. Conclusion: The results for the temperature field and velocity field of the empty storage were analyzed using Fluent. Hanfu apples can maintain good quality during the period of storage, according to our analysis of the Hanfu-apple hardness, weight loss, and change in the sugar-acid ratio during the 90-day preservation period.

• Nutrition Research and Practice
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• v.1 no.4
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• pp.260-265
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• 2007

Preservation methods on the physiological and brewing technical characters in bottom and top brewing yeast strains were investigated. The preserved yeasts were reactivated after 24 months storage and grown up to stationary phase. The samples of filter paper storage indicated a higher cell growth and viability during propagation than those of nitrogen and lyophilization storage independent on propagation temperature. In addition, the filter paper storage demonstrated a faster absorption of free amino nitrogen and a highest level of higher aliphatic alcohols production during propagation than other preservation methods, which can be attributed to intensive cell growth during propagation. Moreover, the filter paper storage showed a faster accumulation for glycogen and trehalose during propagation, whereas, in particular, lyophilization storage noted a longer adaptation time regarding synthesis of glycogen and trehalose with delayed cell growth. In beer analysis, the filter paper storage formed an increased higher aliphatic alcohols than control. In conclusion, the preservation of filter paper affected positively on yeast growth, viability and beer quality independent on propagation temperature. In addition, in this study, it was obtained that the HICF and Helm-test can be involved as rapid methods for determination of flocculation capacity.

• Microbiology and Biotechnology Letters
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• v.18 no.3
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• pp.322-325
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• 1990

During transportation and preservation of Takju, alcohol fermentation has continued to produce $C0_2$ from residual sugar and frequently spoiled owing to bacterial contaminants wich produce organic acids. The authors could preserve Takju for more than 50 days at room temperature by pasteurization without any changes of quality. For the optimal condition of pasteurization, fresh Takju was heated at various temperatures and times. D-Value of the Saccharomyces sp. which isolated from Takju collected at seoul area was 19 see at $55^{\circ}C$. Non-spore forming bacterial contaminants, most of which known to cause acid-spoilage, were decreased when heated at $55^{\circ}C$ for 5 min. The optimal pasteurization condition of Takju was at $55^{\circ}C$ for 10 min. Spore forming bacterial contaminants, considered to be EuciiLw sp., were not sterilized after pasteurized at the optimal condition. However, the spore-forming bacteria could not increase any more and also not cause increment of acidity during preservation even at room temperature for 50 days. Reducing sugar was increased during storage of Takju after pasteurization. This suggests that the residual glucoamylase in Takju is still active after pasteurizsation and keep sweet taste.

• Korean Chemical Engineering Research
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• v.51 no.5
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• pp.602-608
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• 2013

Gas hydrate studies are attracting attention of many researchers as an innovative, economic and environmentally friendly technology when it is applied to $CO_2$ capture, transport, and storage. In this study, we investigated whether $CO_2$ hydrate shows the self-preservation effect or not, that is the key property for developing a novel $CO_2$ transport/storage method. Especially the degree of self-preservation effect for $CO_2$ hydrate was studied according to the particle size of $CO_2$ hydrate samples. We prepared three kinds of $CO_2$ hydrate samples varying their particle diameter as millimeter, micron and nano size and measured their change of weight at $-15{\sim}-30^{\circ}C$ under atmospheric pressure during 3 weeks. According to our experimental result, the lower temperature, larger particle size, and compact structure for higher density are the better conditions for obtaining self-preservation effect.

• The Korean Journal of Mycology
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• v.26 no.1 s.84
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• pp.91-96
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• 1998

Optimal conditions for the preservation of mushroom cultures in sterile distilled water were investigated. Mycelial disks from 12 mushroom cultures were preserved at room temperature, $5^{\circ}C,\;-20^{\circ}C$ and $-75^{\circ}C$ using sterile water and 6 cryoprotectants for 12 months. The maximal viability of mycelial disks was observed at room temperature and $5^{\circ}C$ with the value of 91.7%. At $-75^{\circ}C$, the viability was highest in polyethylene glycol (PEG) and lowest in 10% dimethyl sulfoxide (DMSO). The average mycelial growth was highest for disks preserved at $-75^{\circ}C$ in PEG. PEG was the most suitable for the preservation at $-75^{\circ}C$, although this chemical has rarely been used as a cryoprotectant in fungal culture preservation. The laccase isozyme patterns of the preserved isolate of H. ferrugineum were not changed during preservation at $5^{\circ}C$ in sterile distilled water as compared to that of slant culture.

• Food Science and Preservation
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• v.5 no.2
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• pp.105-110
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• 1998

To find out suitable storage and marketing condition, northern type 'seosan' garlic was stored for 3 months at controlled atmosphere(CA), modified atmosphere(MA), low(0~1$^{\circ}C$) and room temperature(20$\pm$5$^{\circ}C$), and then marketed at low(2~3$^{\circ}C$) and room temperature (20$\pm$5$^{\circ}C$)after storage. The physiological properties of garlic were investigated among treatments. The garlic respiration increased after 2 months at room temperature storage, which seem to be dormancy break time. During storage of garlic by CA, MA condition, sprouting and weight loss were prevented effectively by suppress of respiration, and hardness was maintained higher then those of the others. Decay rate occurred 8.1% at room temperature storage, 2% at MA storage but didn't occurred at CA and low temperature storages. When marketed at room and low temperature after storage, increment of respiration and sprouting were delayed, and changes of weight and hardness were low in garlics stored at CA and MA. Decay rate occurred high in garlics stored at MA and room temperature.

• The Korea Journal of Herbology
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• v.32 no.4
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• pp.25-32
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• 2017

Objectives : Chungsimyeonja-eum (CSYJE; Qingxinlianzi-yin in Chinese; Seishinrenshi-in in Japanese), a traditional herbal medicine, has been used for treating mouth dryness, hyperuresis. This study was designed to determine preservation period of CSYJE. We investigated the stability and biological activity of CSYJE depending on the preservation temperature and periods. Methods : CSYJE decoction was preserved for 0-6 or 12 months at room temperature (RT, $23{\pm}1^{\circ}C$) or refrigeration ($4^{\circ}C$). To evaluate the stability of CSYJE decoction, pH and dissolved solids content were measured. High-performance liquid chromatography (HPLC) analysis was performed to determine marker compounds-liquiritin apioside, liquiritin, baicalin, wogonoside, and glycyrrhizin-in CSYJE. To determine anti-inflammatory effect of CSYJE, prostaglandin $E_2$ ($PGE_2$) was measured in LPS-stimulated RAW 264.7 macrophages. Results : Both at RT and $4^{\circ}C$, pH was decreased depending on the preservation periods. There was no changes in dissolved solids content depending on the preservation temperature and periods. Both at RT and $4^{\circ}C$, the contents of liquiritin apioside and liquiritin were slightly increased at 1 month of storage. The level of baicalin was decreased time-dependently and the disappearance rate at RT is larger than at $4^{\circ}C$. CSYJE inhibited $PGE_2$ production in LPS-stimulated RAW 264.7 cells and maintained inhibitory effect by 12 months both at RT and $4^{\circ}C$. Conclusions : Based on the disappearance rate of the baicalin in CSYJE, the preservation period is recommended within 8 months for RT and 12 months for $4^{\circ}C$.

• Journal of Embryo Transfer
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• v.28 no.2
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• pp.121-125
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• 2013

This study was carried out to investigate the general characteristics of semen such as semen volume, pH, sperm motility and sperm concentration of the semen collected from Shih Tzu dogs (age of 24 to 48 months, weight of 4 to 8 kg) by using the method of digital manipulation of the penis. The effect of preservation temperature and time on motility of fresh semen was also investigated in the present study. Semen was collected for 16 times from 4 male Shih Tzu dogs by multiple ejaculations (four times ejaculation per dog). The average of semen volume, semen pH, sperm motility and sperm concentration of the second fraction containing small volume of the initial third fraction per ejaculation were $2.11{\pm}0.31$ ml, $6.25{\pm}0.07$, $97.59{\pm}1.03%$ and $2.05{\pm}0.14{\times}10^8$ cells/ml, respectively. Average semen volume per ejaculate, semen pH, sperm motility and sperm concentration of the first fraction from the ejaculation were $1.12{\pm}0.15$ ml, $5.99{\pm}0.14$, $16.09{\pm}6.18%$ and $5.16{\pm}2.03{\times}10^5$ cells/ml, respectively. Those of second fraction were $2.07{\pm}0.29$ ml, $6.36{\pm}0.13$, $97.31{\pm}1.36%$ and $2.15{\pm}0.30{\times}10^8$ cells/ml, respectively. Those of third fraction were $2.60{\pm}0.29$ ml, $6.63{\pm}0.08$, $95.72{\pm}1.61%$ and $6.03{\pm}1.83{\times}10^7$ cells/ml, respectively. Sperm motility was significantly higher at $17^{\circ}C$ preservation temperature than at $5^{\circ}C$ or $36^{\circ}C$ during preservation period except 1 h preservation (P<0.05). When preservation temperature was $17^{\circ}C$, sperm motility was $96.69{\pm}1.49%$ at 1 h, $91.38{\pm}1.90%$ at 6 h, $88.38{\pm}2.34%$ at 12 h, $78.13{\pm}4.58%$ at 18 h, $58.44{\pm}8.57%$ at 24 h and $29.56{\pm}5.06%$ at 30 h, respectively.