• Journal of Microbiology and Biotechnology
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• 제7권1호
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• pp.1-7
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• 1997

The efficient manufacture of fermented dairy products on an industrial scale requires a supply of reliable starter cultures with properties suited to desired product specifications. These cultures must be backed by relevant research and development activities. This article describes the issues involved in establishing a centre to provide starter culture R & D for a group of independent cheese manufacturing companies, and discusses a strategic approach to the management of starter cultures.

• 산업기술연구
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• 제17권
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• pp.175-182
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• 1997

Various types of electronic starter have been developed for the general fluorescent lamps with magnetic-type ballasts. However, the FL032/T8 fluorescent lamp requires higher voltage to discharge the lamp. The general starter with two-terminal is not suitable for the FL032/T8 slim-line type fluorescent for its higher discharge voltage. The suitable starter with three terminals have been studied for the FL032/T8 lamp in this paper. The developed starter have better characteristics in view points of the discharge voltage magnitude. We have proposed and designed the three terminals electronic starter. The proposed starter have been experimented and compaired with the other 2-terminal general starters. By the experimental results, we have concluded that the proposed starter is suitable to the FL032/T8 lamp.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 1996년도 추계학술발표회논문집
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• pp.49-52
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• 1996

This paper reports the development of an electronic starter for fluorescent lamps, which is so smartly designed that can be used directly in existing installations. The key point of the design lies in the protection of lamp filaments by sufficient preheating and at the same time in the control of time constant for start-up circuit. The starter is consisted of three system parts: a rectifier pact, a switching part. and a gate control part. The characteristics of the developed electronic starter is compared with those of a conventional glow starter. As a result, blackening of lamps is almost reduced due to the stable and idealized start-up characteristics. And, furthermore, it is shown that its slaving time is shortened at about half the level of the conventional one and the starting power is also reduced.

• 한국식품영양과학회지
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• 제32권8호
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• pp.1245-1252
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• 2003

Starter활성에 미치는 요인들을 조사하기 위하여 밀가루 단백질 함량, 수분첨가비율 및 다양한 영양원을 첨가하면서 starter에 내재된 미생물의 생육과 pH및 적정산도의 변화정도를 관찰하면서 최대의 활성을 나타내는 starter배합을 제시 하고자 하였다. 또한 완성된 starter를 빵 제조에 효모 대신 첨가하면서 식빵의 품질 및 관능 특성을 검토하여 천연 제빵 발효종으로서 starter의 상업적 이용 가능성을 타진하였다. 국내에서 시판되고 있는 밀가루에는 효모보다 젖산균의 수가 100배정도 더 많이 함유되어 있었다. 밀가루 단백질 함량이 많을수록 pH 및 적정산도의 변화가 적어 미생물의 생장에 더 안정적인 경향을 나타냈으며 단백질 함량은 강력분 수준(12.0%이상)이 starter 제조에 적합하였다. 수분 첨가함량이 60% 정도인 경우는 110% 이상인 경우보다 균수가 10배 이상 적었으며 수분함량이 200%인 경우는 pH및 적정산도의 변화가 커서 오히려 starter의 활성을 저해하는 경향을 나타내었다. 따라서 적정 수분함량은 강력분인 경우 110%가 적정하였다. 식염 및 설탕의 첨가는 효모 및 젖산균의 수를 크게 증가시켰으나 올리고당은 거의 영향을 미치지 않았다. 한편 설탕의 농도가 10%이상 그리고 식염의 농도가 2%이상으로 증가되면 삼투압의 영향으로 균의 생장이 억제되는 경향을 나타내었다. Starter의 시험구 중 강력분을 사용하고 수분함량 110%에 설탕 5% 및 식염 1%을 사용한 starter의 발효 팽창력 이 대조구보다 높았다. Starter를 첨가하여 만든 빵은 효모를 첨가하여 만든 빵에 비하여 체적을 제외한 모든 품질 특성에서 우수하였으며 특히 관능 특성에서 유의적으로 높은 점수를 받았다. 이상의 결과를 종합해 보면 강력분, 수분 110%, 설탕 5% 및 식염 1%를 배합하여 3일 동안 3$0^{\circ}C$에서 refresh시킨 starter는 실제 제빵시 효모의 효과적인 대체제로서 사용할 수 있으며 상업적 이용 가능성이 있는 것으로 나타났다.

• Asian-Australasian Journal of Animal Sciences
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• 제29권7호
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• pp.971-978
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• 2016

The aim of this study was to evaluate the effect of replacing corn grain for sugar cane molasses (MO) or glucose syrup (GS) in the starter concentrate on performance and metabolism of dairy calves. Thirty-six individually housed Holstein male calves were blocked according to weight and date of birth and assigned to one of the starter feed treatments, during an 8 week study: i) starter containing 65% corn with no MO or GS (0MO); ii) starter containing 60% corn and 5% MO (5MO); iii) starter containing 55% corn and 10% MO (10MO); and iv) starter containing 60% corn and 5% GS (5GS). Animals received 4 L of milk replacer daily (20 crude protein, 16 ether extract, 12.5% solids), divided in two meals (0700 and 1700 h). Starter and water were provided ad libitum. Starter intake and fecal score were monitored daily until animals were eight weeks old. Body weight and measurements (withers height, hip width and heart girth) were measured weekly before the morning feeding. From the second week of age, blood samples were collected weekly, 2 h after the morning feeding, for glucose, ${\beta}$-hydroxybutyrate and lactate determination. Ruminal fluid was collected at 4, 6, and 8 weeks of age using an oro-ruminal probe and a suction pump for determination of pH and short-chain fatty acids (SCFA). At the end of the eighth week, animals were harvested to evaluate development of the proximal digestive tract. The composition of the starter did not affect (p>0.05) concentrate intake, weight gain, fecal score, blood parameters, and rumen development. However, treatment 5MO showed higher (p<0.05) total concentration of SCFAs, acetate and propionate than 0MO, and these treatments did not differ from 10MO and 5GS (p>0.05). Thus, it can be concluded that the replacement of corn by 5% or 10% sugar cane molasses or 5% GS on starter concentrate did not impact performance, however it has some positive effects on rumen fermentation which may be beneficial for calves with a developing rumen.

• 한국축산식품학회지
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• 제38권1호
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• pp.189-202
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• 2018

This study was conducted to evaluate the effects of fermenting temperature on the applicability of Lactobacillus plantarum for production of fermented sausages as starter cultures, and its applicable efficiency was also compared with those inoculated with commercial starter culture or non-inoculated control. The L. plantarum isolated from a naturally-fermented meat, identified by 16S rDNA sequencing and again identified by de novo Assembly Analysis method was used as a starter culture. Six treatments: 3 with L. plantarum at different fermenting temperatures (20, 25 and $30^{\circ}C$), and other 3 treatments (1 with commercial starter culture, 1 with its mixture with L. plantarum and 1 non-inoculated control) fermented under the same conditions ($25^{\circ}C$) were prepared. Results revealed that the fermenting temperature considerably affected the pH change in samples added with L. plantarum; the highest pH drop rate (1.57 unit) was obtained on the samples fermented at $30^{\circ}C$, followed by those at $25^{\circ}C$ (1.3 unit) and $20^{\circ}C$ (0.99 unit) after 4 days fermentation. Increasing the temperature up to $30^{\circ}C$ resulted in significantly lower spoilage bacteria count (5.15 log CFU/g) and lipid oxidation level in the products inoculated with L. plantarum. The sensory analysis also showed that the samples added with L. plantarum at $30^{\circ}C$ had significantly higher odor, taste and acceptability scores than those fermented at lower temperatures. Under the same processing condition, although the L. plantarum showed slightly lower acidification than the commercial starter culture, however, it significantly improved the eating quality of the product.

• Journal of Microbiology and Biotechnology
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• 제30권9호
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• pp.1404-1411
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• 2020

Lactic acid bacteria (LAB) play an important role in dairy fermentations, notably as cheese starter cultures. During the cheese production and ripening period, various enzymes from milk, rennet, starter cultures, and non-starter LABs are involved in flavor formation pathways, including glycolysis, proteolysis, and lipolysis. Among these three pathways, starter LABs are particularly related to amino acid degradation, presumably as the origins of major flavor compounds. Therefore, we used several enzymes as major criteria for the selection of starter bacteria with flavor-forming ability. Lactococcus lactis subsp. lactis LDTM6802 and Lactococcus lactis subsp. cremoris LDTM6803, isolated from Korean raw milk and cucumber kimchi, were confirmed by using multiplex PCR and characterized as starter bacteria. The combinations of starter bacteria were validated in a miniature Gouda-type cheese model. The flavor compounds of the tested miniature cheeses were analyzed and profiled by using an electronic nose. Compared to commercial industrial cheese starters, selected starter bacteria showed lower pH, and more variety in their flavor profile. These results demonstrated that LDTM6802 and LDTM6803 as starter bacteria have potent starter properties with a characteristic flavor-forming ability in cheese.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2009년도 춘계학술대회 논문집
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• pp.7-10
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• 2009

우주발사체용 액체추진제 로켓엔진을 시동할 때 사용되는 터보펌프 시동기에 적용하고자 고체추진제 개발 및 특성 평가를 수행하였다. 터보펌프 시동기용 추진제의 배출가스는 기계적인 부식 또는 대기오염 등의 이유로 화염온도가 낮아야 하고 고체입자 잔사 및 독성이 적은 것이 바람직하며, 작동시간이 어느 정도 유지가 되어야 하기 때문에 비교적 낮은 연소속도가 필요하다. 본 연구에서는 PCP계열의 바인더를 사용하고 oxygen balance나 점화성에서 유리한 DHG(Dihydroxy glyoxime)을 냉각제를 사용하는 추진제 조성을 개발하여 연소속도와 기계적 물성 등의 특성평가를 실시하였으며, 최종적으로는 지상연소시험을 통하여 터보펌프 시동기의 성공적인 개발 가능성을 입증하였다.

• 제어로봇시스템학회논문지
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• 제10권3호
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• pp.286-293
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• 2004

This paper presents the result of a study on the starter control for a turbo generator. Because a starter in gear box type turbo-generator system is composed of gearbox and brush DC motor, it should be replaced with High Speed Generator(HSG)) in HSG type Turbo-generator. There-ore, it is necessary to design a new starting algorithm and starter. In gearbox type system, brush DC motor is rotated to the designed speed using low voltage-high current battery power. After brush DC motor speed is increased to several times by gearbox, gas turbine engine can be rotated to designed starting speed. If we implement a starter with High Speed Generator(HSG), it is necessary to drive high-speed generator to high-speed motor. High-speed generator with permanent magnet on rotor has a low leakage inductance fur driving high-speed rotation, and it is necessary high DC link voltage for inverter when High-speed generator is driven to high speed. This paper presents result of development of the boost converter for converting high voltage DC from low battery voltage and design of the inverter for controlling a high frequency current to be injected to motor winding. Also, we show performance of the designed starter by driving the turbo generator.

• 한국자동차공학회논문집
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• 제14권1호
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• pp.123-128
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• 2006

The proposed mathematical model of the starter-generator system incorporates the motor speed, battery voltage and the desired current to estimate the moment generation capabilities of the starter-generator and the actual current of the battery system. The fundamentals for this mathematical modeling are the simulated results of the experimental data. These pertinent data are used in establishing the governing equations for the determination of motor moments, actual battery currents and efficiencies of the system's operation at different loading characteristics and speed regions. The derived equations will be used into simulation programs to predict the fuel efficiency, vehicle characteristics of a hybrid electric vehicle equipped with a transmission starter-generator which will be developed.