• The Korean Journal of Food And Nutrition
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• v.7 no.2
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• pp.151-158
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• 1994

This study was carried out to clear up the cause of low-acid producing phenomenon occurred In non-fat dry milk during liquid-yoghurt fermentation by Lactobacillus case, and to present its improving methods. All samples of non-fat dry milks which were low in TCA-soluble peptides showed low-acid production, but those high in TCA-soluble peptides showed high-acid production. The addition of trypsin-hydrolysate of Na-caseinate to non-fat dry milk showed some improving effect on acid production but that of papain-hydrolysate did not show any improving effect and that of bacterical neutral protease-hydrolysate showed some inhibitory effect. The improving effects on growth and acid production of lactic acid bacteria were more prominent when the trypsin-hydrolysate of Na-caseinate was added. to such fermenting system in which the levels of TCA-soluble peptides and the proteolytic ability of starter bacteria were abnormally low. The liquid-yoghurt made with non-hydrolysed Na-caseinate and defective non-fat dry milk showed precipitate occurrence but that with trypsin-hydrolysate of Na-caseinate and defective non-fat dry milk did not make any precipitate during storage as with normal non-fat dry milk.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.252-259
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• 2001

It is derived for the temperature profile in a cylindrical and planar shape capillary pumped loop evaporators subject to a uniform heat flux prior to the initiation of boiling using the finite difference method. The results of the analysis allow for the determination of applied power levels for which nucleation is likely to occur only within the vapor grooves of the evaporator while maintaining subcooling in the liquid core, thereby increasing the likelihood of a successful startup. Also, limits are found for which additional increases in the applied heat flux do not increase the temperature difference between the vapor grooves and the wick-liquid core interface. Several advantages of larger diameter evaporators observed experimentally in startup are explained and quantified by the model. This analysis is appropriate for standard capillary pumped loop evaporators during a fully-flooded startup as well as starter pump designs and loop heat pipes.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.2
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• pp.211-218
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• 2002

It has been investigated for the temperature profile in a planar evaporator of micro-cooler subject to a uniform heat flux prior to tole initiation of boiling. The results of the analysis allow for the determination of applied power levels fur which nucleation is likely to occur only within the vapor grooves of the evaporator while maintaining subcooling in the liquid core, thereby increasing the likelihood of a successful startup. Also, limits are fecund for which additional increases in the applied heat flux do not increase the temperature difference between the vapor grooves and the wick-liquid core interface. This analysis is appropriate for the microscale evaporators of micro-cooler during a fully-flooded startup as well as starter pump designs and micro-CPLs(capillary pumped loops). The results are useful in the initial basic design of microscale heat transfer devices.

• The Korean Journal of Mycology
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• v.16 no.4
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• pp.193-203
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• 1988

The changes of pH, titrable acidity, nitrite and dimethylamine(DAM) content in the various different kinds of the rice wine staters during the fermentation were studied, and the changes of nitrosodimethymaine(NDMA) contents were also determined by High Pressure Liquid Chromatography. After 24hrs, fermentation rice wine starter, pH was generally decreased to below 5 and after full fermentation the acidities were from 0.51 to 0.89 as succinic acid. After 12hrs, fermentation nitrate contents were rapidly decreased. The large amount of nitrite was formed in the beginning of the fermentation. But by the increase in the acidity due to the further fermentation nitrite contents were gradually disappeared. Generally the DMA contents of each rice wine starter were kept unchanged. On completion of fermentation, NDMA contents of starter added with nitrite and DMA were 472.1 ppb. The starter added with DMA was 329.0 ppb, whereas the other added with nitrite was 229.0 ppb, and control without addition of nitrite and DMA was 24.4 ppb. But the rice wine sold in market was not detected any NDMA at all.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.4
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• pp.403-409
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• 1995

A growth experiment was conducted to evaluate the nutritivie values of supplemental lysine and methionine in broiler chicks. Two types of L-lysine, liquid and powder type, and DL-methionine were added to the diets at different levels of dietary protein with two growth phases, 0-3 weeks and 4-6 weeks named starter and grower, respectively. Six hundred seventy two chicks were allotted in 14 treatments; 3 controls by dietary CP level (starter-grower) with CP 23-21%, CP 21-19% and CP 20-18, 8 groups of liquid and powder lysine supplementation of 0.1, 0.2, 0.3 and 0.4%, and 3 groups of lysine and methionine supplementation. Body weight, feed intake, and excreta were measured and analyzed to determine growth performance, amino acid digestibilities, and the quantity of excreted nitrogen in feces. Chicks fed CP 23-20 with 3,200 ME kcal showed significantly better growth performance than those fed CP 21-18 for 6 weeks. The supplementation of 0.2% of either type of lysine to CP 21-19 diet improved weight gain and feed efficiecy to the extent that CP 23-21 diet was fed. Physical type of lysine did not affect chick's growth and amino acid digestibilities of the diets. The level of CP in the diet significantly affected nitrogen excretion in feces. Supplementation of lysine and methionine to CP 21-18 diet reduced fecal nitrogen by 10% compared to CP 23-21 diet. It was confirmed that 0.2% of supplemental lysine to the broiler diet spared the dietary protein by 3%, and also reduced nitrogen excretion in feces by 10%.

• Korean Journal of Food Science and Technology
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• v.43 no.5
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• pp.655-658
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• 2011

The possible application of Lactobacillus spp. as a functional starter culture to ferment galgeuntang (GT) and to produce bioactive isoflavone (daidzein) was investigated. Lactobacillus casei KFRI 127, L. plantarum KFRI 144, L. bulgaricus KFRI 344 were used for GT fermentation. Acid development and quantification of isoflavones using high-performance liquid chromatography were performed after fermentation at 37$^{\circ}C$ for 48 h. All the tested Lactobacillus spp. lowered pH to about 3.8 in 48 h and L. plantarum KFRI 144 exhibited 89.9% hydrolysis rate of daidzin (79.1-8.0 ${\mu}g$/mL) during fermentation. The content of daidzein in GT fermented with L. plantarum KFRI 144 was increased by 6.6-fold (3.6-23.9 ${\mu}g/mL$). These results demonstrate that L. plantarum KFRI 144 has potential as functional starter culture for manufacturing fermented GT with higher isoflavone bioavailability.

• Preventive Nutrition and Food Science
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• v.9 no.2
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• pp.138-143
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• 2004

Soybean curd residues (SCR) obtained from hot and cold manufacturing processes were fermented by indigenous microorganisms, Lactobacillus rhamnosus LS and Bacillus firmus NA-l for 15 h at 37$^{\circ}C$. The pH, acidity, viable cell counts, and tyrosine content were evaluated in samples with variations in sugar, starter and type of SCR. The raw Doowon SCR (D-SCR, cold-processed) fermented by indigenous microorganism had a 0.9% acidity and 6.7 ${\times}$ 10$^{7}$ CFU/g viable cell counts, compared with the 0.11 % acidity and 6.7 ${\times}$ 10$^{6}$ CFU/g viable cell counts of raw fermented Pulmuwon SCR (P-SCR, hot-processed). After fermentation of raw P-SCR with 1 % glucose and 1 % L. rhamnosus LS starter, the viable cell counts, tyrosine content and acidity were 4.7 ${\times}$ 10$^{8}$ CFU/g, 16.3 mg% and 0.9%, respectively. In addition, the raw P-SCR fermented with Bacillus firmus NA-l as co-starter had a 0.45% acidity, 2.4 ${\times}$ 10$^{8}$ CFU/g lactic acid bacteria, and 3.3 ${\times}$ 10$^{6}$ CFU/g Bacillus sp. In particular, the tyrosine content was increased 5 fold. The drying of fermented SCR was completed by hot-air drying (5$0^{\circ}C$) within 12 h; the dried P-SCR and D-SCR had 1.8 ${\times}$ 10$^{7}$ CFU/g and 5.3 ${\times}$ 10$^{6}$ CFU/g viable cell counts, respectively. The concentrate of methanol extract from fermented D-SCR inhibited the initial cell growth of E. coli, Staphylococcus aureus and Pseudomonas aeruginosa in liquid culture.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2524-2527
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• 2007

Solid propellant gas generators (SPGG) play a role as a turbopump starter in liquid propellant propulsion systems by supplying pressurized gas to power turbines for engine start. For such a purpose, the propellants should burn with a relative low flame temperature and the combustion gas should not contain corrosive constituents such as chlorine compounds. In accordance with these requirements, stabilized AN-based propellants have been usually used as the most appropriate oxidizer for propellant compositions. However, the burning area of the propellant intends to increase to satisfy the required mass flux because of its low burning rate. Consequently the burning area incensement brings on the SPGG size augmentation. A flow restriction such as filters is applied to decrease the SPGG size by rising up the combustion pressure resulting in increasing the burning rate. The feasibility of the size reduction of SPGG by the employment of filters have been studied. The preliminary results of this study show that the considerable reduction of SPGG size would be achievable just by installing a filter with relatively high pressure loss coefficient.

• Aerospace Engineering and Technology
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• v.7 no.2
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• pp.170-175
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• 2008

In this study, it was investigated that the characteristics of startup and compatibility using several type hot and cold gases. The characteristics of starting LRE by pyro starter was compared with that by a Helium spinner. The compatibility of pyro gas, a gaseous Helium, Hydrogen+Nitrogen mixture gas, and air was investigated by a simple 1D turbine analysis considered the properties of each gas and turbine efficiency. Most of them were compatible to start up the LRE however air was properly used only for low power mode of turbine.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.11a
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• pp.216-220
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• 2006

In this study, it was investigated that the characteristics of startup and compatibility using several type hot and cold gases. The characteristics of starting LRE by pyro starter was compared with that by a He spinner. The compatibility of pyre gas, a gaseous He, H2+N2 mixture gas, and air was investigated by a simple 1D turbine analysis considered the properties of each gases and turbine efficiency. Most of them were compatible to start up the LRE but air was properly used only when the turbine was low power mode.