• Proceedings of the KIEE Conference
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• 2003.04a
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• pp.300-302
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• 2003

Fluorescent lamp converts electrical energy Into light energy. Generally we use both electronic ballast and glow starter method in the house. We developed 40W electronic starter and its characteristic is verified by experiments. The efficiency of ballast is improved by using the LC Parallel reasonance circuit at input stage and LC series reasonance circuit at out-put stage.

• Journal of Dairy Science and Biotechnology
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• v.24 no.1
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• pp.65-73
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• 2006

This study was to review recent reports in effects of various starter cultures on the viscosity in stirred yogurt. The rheological properties of yogurt have received considerable attention in the literature. Most yogurts are typically made by mixed cultures of Lactobacillus bulgaricus and Streptococcus thermophilus. The viscosity of yogurt made by mixed cultures was much higher than that of yogurt by single cultures. Since texture of stirred yogurt is the result of both acid aggregation of casein micelles and production of exopoly-saccharides, it is suggested that yogurt be made by the exopolysaccharide-producing cultures in order to increase viscosity, Both types of exopolysaccharides are capsule and loose slime(ropy). But it is desirable to use encapsulated nonropy strains. And Bifidobacteria affects adversely to the viscosity of yogurt. Therefore, starter cultures which have an effect on yogurt viscosity have been widely demonstrated. This review is the search for the development of viscosity in stirred yogurt.

• Microbiology and Biotechnology Letters
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• v.47 no.2
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• pp.234-241
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• 2019

In Korea, traditional doenjang is manufactured using the conventional method at home and by small-scale enterprises. Because this age-old process depends on natural inoculation of various microorganisms, it is difficult to reproduce or maintain consistency in the final product quality across batches. Moreover, doenjang occasionally prepared by this method raises safety concerns related to aflatoxin, biogenic amine, and Bacillus cereus contamination. To develop starters that can be conveniently used at home or in small industry settings for the manufacturing of safe and flavor-improved doenjang, autochthonous microbe starters were developed in dried forms as ready-to-use starters. Each starter powder prepared by heat- or freeze-drying methods remained stable even after 24-week storage. These ready- to-use starter powders were successfully applied to lab-scale fermentation for the production of safe and flavor-improved doenjang. We believe that these ready-to-use starter powders will benefit small-scale enterprises in the manufacturing of doenjang of good reproducible quality.

• Journal of Dairy Science and Biotechnology
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• v.39 no.1
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• pp.20-26
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• 2021

Lactase (β-galactosidase) is abundant in the small intestine during early childhood and gradually decreases with age. Lactic acid bacteria (LAB) present in yogurt could survive in the stomach, and lactase produced by these LAB can aid in lactose breakdown in the small intestine, thereby reducing lactose intolerance. This study aims to provide preliminary data for development of lactose-free yogurts for the elderly, and investigate the effect of lactose-hydrolyzed milk on the growth of starter cultures. The pH during yogurt fermentation using lactose-free milk was slightly higher at 2 and 4 h of incubation, but reached 4.5 at the end of incubation, similar to that of the yogurt prepared from regular milk. The number of viable cells of Streptococcus thermophilus reached 108 CFU/mL after 2 h of incubation and increased to 109 CFU/mL after 4 h of incubation. During yogurt fermentation, the viable cells of Lactobacillus species and Bifidobacterium longum did not affect lactose hydrolysis. Although lactose-hydrolyzed milk did not promote the growth of starter cultures, manufacturing yogurt with lactose-free milk could be beneficial for the intestinal health of lactose-sensitive elderly.

• The Korean Journal of Food And Nutrition
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• v.9 no.3
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• pp.236-241
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• 1996

Starter cultures were developed for the extension of the shelf life of bread. Lactobacillus plantarum and Bifidoacterium longum were selected as the mixed culture with Propionibacterium freudenreichii. P. fredenreichii with B. longum and L. plantarum produced 2.261% and 1.715% total acid, and pH value of cultured solutions was near 3.95. Propionic acid was produced 14 ~16 mg/ml by P. freudenreichii with L. plantarum and B. longum during 17 days, which was more than that of L. brevis. The pH values of the bread were 4.83 and 4.89 in respect to B. longum and L. plantarum when the fermented products were used to make the bread. Mold was not found for 10 days of storage of the bread at room temperature when the fermented products of B. longum were used for making bread. 37$^{\circ}C$, pH 6.0 and the lowest agitation were optimum conditions for the production of propionic acid in the scaled up fermentation.

• Proceedings of the KIEE Conference
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• 1998.07f
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• pp.2088-2090
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• 1998

A low-cost electronic starter is developed to decrease ignition failure significantly through successive starting trial and to prevent overheating at the end of fluorescent lamp life. Moreover, it has an additional feature of being capable of ignition at the recovered lamp voltage without any circuit correction. The developed electronic starter is consisted of four parts - a half wave rectifier circuit, a timer circuit, a switching circuit and a protection circuit. The protection circuit made up of a transistor and capacitors utilizing capacitive characteristics, carries out successive starting trial and end-of-life protection. Lamp ignition is completed within 0.5 seconds with taking advantage of a high preheating current from the half-wave rectifier circuit. Nevertheless, its performance is proved to be very excellent through a standard switching endurance test.

• Proceedings of the KIPE Conference
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• 2007.07a
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• pp.397-399
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• 2007

This paper presents a simple electronic starter for single phase induction motor (SPIM). It replaces the centrifugal switch in the auxiliary winding circuit of the capacitor start type SPIM. The centrifugal switch disconnects the auxiliary winding when the motor gets close to its rated speed. The presence of the centrifugal switch, with its possibly fluttering contacts, reduce reliability of SPIM. The operation principle of the proposed electronic starter is explained, and illustrated with experimental results.

• Journal of Microbiology and Biotechnology
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• v.29 no.11
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• pp.1729-1738
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• 2019

In sourdough fermentation, lactic acid bacteria perform important roles in the production of volatile and antimicrobial compounds, and exerting health-promoting effects. In this study, we report the probiotic properties and baking characteristics of Lactobacillus plantarum SPC-SNU 72-2 isolated from kimchi. This strain is safe to use in food fermentation as it does not carry genes for biogenic amine production (i.e., hdc, tdc, and ldc) and shows no β-hemolytic activity against red blood cells. The strain is also stable under simulated human gastrointestinal conditions, showing tolerance to gastric acid and bile salt, and adheres well to colonic epithelial cells. Additionally, this strain prevents pathogen growth and activates mouse peritoneal macrophages by inducing cytokines such as tumor necrosis factor-α, interleukin (IL)-6, and IL-12. Furthermore, the strain possesses good baking properties, providing rich aroma during dough fermentation and contributing to the enhancement of bread texture. Taken together, L. plantarum SPC-SNU 72-2 has the properties of a good starter strain based on the observation that it improves bread flavor and texture while also providing probiotic effects comparable with commercial strains.

• Food Science and Biotechnology
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• v.17 no.5
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• pp.940-946
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• 2008

In the development of a nutrient enhanced functional food, kimchi was produced by using high $\gamma$-aminobutyric acid (GABA) producing lactic acid bacterium as a starter strain. The strain isolated from kimchi was identified by using an API kit and named Lactobacillus sp. OPK 2-59. Kimchi was produced by 3 methods 1) monosodium glutamate (MSG) added (M group); 2) starter added (S group); 3) MSG+starter added (M&S group). The produced kimchi was fermented for 24 hr in an incubator at a temperature of $15^{\circ}C$ and stored at $0-1^{\circ}C$ to examine its characteristics. The M&S group exhibited a sharper increase in acidity and a steeper fall in pH as well as a higher number of lactobacilli. The M&S group kimchi had 18 mg/100 g (fresh weight, f.w.) of GABA, whereas the M and S group each had 6 mg/100 g (f.w.) GABA. According to functional evaluation, the M&S group kimchi, which has higher GABA, was not significantly different in taste, color, texture, or smell, but the M&S group was generally superior. In summary, using Lactobacillus sp. OPK 2-59 and MSG, a high quality kimchi with increased GABA content can be produced as a functional food.

• The Transactions of the Korean Institute of Power Electronics
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• v.9 no.1
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• pp.17-24
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• 2004

The starter of the turbo generator is composed of a high speed generator(HSG), an inverter and a boost converter instead of a gearbox, a DC motor and a low-voltage battery in the starter of the turbo shaft generation system. Because turbo generator is needed a high speed motoring at start-up, high speed generator has a low leakage inductance and inverter need a high DC link voltage. In this study, for developing the stater of a turbo generator, a boost converter with a high capacity was developed to convert high voltage from a low battery voltage. And for controlling a high frequency current to be injected to a motor winding with a low leakage inductance, the inverter with a high precision and a high speed operation was designed and for a stable ignition, the starting algorithm of a turbo generator was proposed. Turbo generator was started by the starter developed to verify the performances.