• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.12
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• pp.1583-1588
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• 2007

PC-camera based automatic titration was executed in the acidity analyses of vinegar, milk and Takju. The average hue value (Havg) of 144 pixels in the image of the sample solution being titrated was computed and followed up at regular time intervals during titration in order to detect the titration end point. The Havg increase of 5 degrees from the first Havg was regarded as reaching at the end point in the cases of vinegar and milk. The Havg increase set up to detect the end point was 70 degrees in the case of Takju. In the case of vinegar, the volume of added titrant (0.1 N NaOH) was $21.409{\pm}0.066mL$ in manual titration and $21.403{\pm}0.055mL$ in automatic titration (p=0.841). In the case of milk, it was $1.390{\pm}0.025mL$ in manual titration and $1.388{\pm}0.027mL$ in automatic titration (p=0.907). In the case of Takju, it was $4.738{\pm}0.028mL$ in manual titration and $4.752{\pm}0.037mL$ in automatic titration (p=0.518). The high p values suggested that there were good agreements between manual and automatic titration data in all three food samples. The automatic method proposed in this article was considered to be applicable not only to acidity titrations but also to most titrations in which the end points can be detected by color change.

• Journal of the Korean Chemical Society
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• v.45 no.6
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• pp.513-519
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• 2001

An optical semi-automatic titrator was constructed employing the technique of the reflectance spectrometry and was tested for the determination of the end points of the acid-base, precipitation, and EDTA titrations. And since the current optical semi-automatic titrator built on the principle of the reflectance spectrometry could be successfully used even for the determination of the end point in the precipitation titration where the solid particles are formed during the titration process, it was found to be feasible that a completely automated optical titrator would be designed and built based on the current findings.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.03a
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• pp.65-65
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• 2011

천연염색에 대한 관심이 높아지고 있지만 색상의 재현성, 견뢰도의 취약성, 디자인의 제한성의 문제로 실용화의 한계에 부딪히고 있다. 이를 극복하기 위하여 본 연구는 침염 위주의 천연 염색에서 벗어나 키토산을 바인더로 이용하는 날염의 유효성을 검토하고자 한다. 본 연구에서는 키토산을 바인더로 이용한 방법을 제시하고자 키토산과 광물성, 동 식물성 안료를 혼합하여 날염호를 조제하여 날염하였다. 키토산의 점도와 농도, 키토산을 이용한 바인더와 안료의 비율 등을 변화시키고 날염직물의 색상과 염착량, 세탁 일광 마찰 견뢰도를 측정하여 적정조건을 도출하였다. 기존의 합성바인더와 구아검을 사용한 경우의 색상, 염착량, 견뢰도와 비교하여 키토산 날염 바인더로서의 유효성을 검토하였다. 키토산을 바인더로 이용한 날염방법에서 적정 점도는 저 중점도, 농도는 1.7%정도가 적절한 것으로 판단하였다. 날염호 제조시 안료의 비율을 증가시켜 진한 색상을 얻을 수 있었으며, 그 비율은 광물성 안료의 경우 1:4, 동 식물성 안료의 경우 1:10까지 변화시켜 명도의 차이를 나타낼 수 있다. 실험결과를 바탕으로 적정조건에서 날염한 직물의 견뢰도를 평가한 결과, 광물성 안료의 경우 4등급 이상, 동 식물성 안료의 경우 3등급 이상으로 우수하게 평가되었다. 안료의 비율이 높아지면 마찰 견뢰도는 감소하였다. 키토산, 구아검, 합성바인더의 색상과 견뢰도를 비교해 본 결과 색상은 동일한 계열로 나타났으며, 키토산을 바인더로 이용한 경우 세탁, 일광, 마찰 견뢰도는 구아검보다 우수하게 평가되었다. 합성바인더의 경우 세탁, 마찰 견뢰도는 비슷하게 나타났으며, 일광견뢰도의 경우 키토산이 더 우수하게 평가되었다.

• Applied Biological Chemistry
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• v.34 no.3
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• pp.242-248
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• 1991

The sucrose, MSG, fresh oyster and salted-fermented anchovy and shirmp were added into Kimchi in the concentration range of $1{\sim}3%$ and studied for their effects on the changes in chemicl properties and fermentation rate. The control Kimchi was prepared with addition of 2% red pepper, garlic, Welsh onion and 1% ginger. It was found that the fermentation rate was increased as the concentration of all of ingradients tested increased. Among them M.S.G affected most significantly. However, ascorbic acid formed was reduced for those Kimchi added with salted-fermented anchovy and shrimp while the changes in pH and titrable acidity was affected a little.

• Food Science and Preservation
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• v.11 no.1
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• pp.34-37
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• 2004

Calcium powder from whey (WCF) was added to enrich the calcium content of kimchi, and the mixing ratios of it to salted Chinese cabbage were 0.5, 1.0 and 1.5％. Quality characteristics of kimchi such as pH, titratable acidity, reducing sugar content and microbial loads were measured during fermentation at 10$^{\circ}C$. Kimchi samples with WCF showed a higher level in pH and titratable acidity than that of control during fermentation. Kimchi having higher WCF maintained a higher in pH and titratable acidity, and titratable acidity was above 1.0％ about 12 days in kimchi sample with 0.5％ WCF. Reducing sugar content was steadily decrease after 5 days, and control maintained a higher than others. Microbial load was similar until 10 days, but control was lower than kimchi samples with WCF. Based on the titratable acidity, kimchi with WCF had a limitation in shelf life.

• Korean Journal of Food Science and Technology
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• v.21 no.1
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• pp.100-108
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• 1989

A study relating the sugar contents of radishes to the final titratable acidities(TA) after complete fermentation was conducted to get an idea of selecting radish varieties to improve storage stabilities of fermented pickled radish cubes. Thirty six varieties of spring-sowing and thirty four varieties of autumn-sowing radishes were chosen to ferment to measure their final TA in relation to their sugar contents. The sugar contents of spring-sowing radishes were in the range from 2.40 to $3.71^{\circ}\;Brix$ and the final TA ranged from 1.15 to 1.65%. The sugar contents of autumn-sowing radishes were in the range from 4.00 to $5.53^{\circ}\;Brix$ and the final TA ranged from 1.45 to 2.00%. The final TA obtained after complete fermentation were found to be directly proportional to the sugar contents of radishes, showing that TA equals to 0.29x+0.4428, where x is sugar content of radish. From the equation, since a properly aged fermented pickled vegetable is believed to have a TA range from 0.6 to 0.8%, a radish of a sugar content ranging from 0.6 to $1.3^{\circ}\;Brix$ will make fermented pickled radish cubes which will not be overacidified during the prolonged storage period.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.941-947
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• 1998

We isolated seventy two lactic acid bacteria and two hundred yeast from traditional Andong sikhe. Microorganisms were isolate from 4 kinds of traditional Andong sikhe. The optimum temperature and pH for growth of sikhe yeast, No. SCS 5, was $30^{\circ}C$ and 4.5, respectively. SCS 5 produced $CO_2$ gas and 1.5% of alcohol in malt extract broth. SCS 5 was identified as S. cersvisiae from the observation of shape of vegetative reproduction, morphological and cultural chararteristics, fermentation and assimilation of carbon sources, and physiological characteristics.

• Journal of Animal Environmental Science
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• v.5 no.3
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• pp.197-202
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• 1999

퇴비화 재료를 혼합하는 목적은 재료를 퇴비황에 최적조건으로 조성하여 퇴비화 성능을 향상 시키고 취기발생을 억제하기 위함이다. 퇴비화성능에 미치는 요인으로서는 C/N비, 수분 함량, 산도(pH), 산물밀도, 입자크기 등이 있다. 이 중에서 C/N비는 적정값으로 조성하기 어렵다. 본 자료는 퇴비재료의 적정 수분 함량 및 C/N비를 조성하기 위해 각 요소재료의 혼합비율을 제시하고 있다.

• The Korean Journal of Mycology
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• v.47 no.3
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• pp.233-240
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• 2019

This study was performed to develop a useful method for substrate pH adjustment in bottle cultivation of Grifola frondosa. Four types of organic acid solution-citric acid, malic acid, tartaric acid, and succinic acid-were added at 0.5% to 3.0% (w/v) into the substrate. The pH after the organic acid treatments ranged from 3.8 to 4.8 for the mycelial growth of G. frondosa after sterilization. Supplementation with succinic acid at 0.5% resulted in a shorter cultivation period and higher consistent yields compared to other organic acid treatments. These results indicate that the technique we developed is beneficial for higher production of G. frondosa using bottle cultivation.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2005.10a
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• pp.276-279
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• 2005

본 연구는 가루녹차를 첨가한 기능성 요구르트를 개발하기 위한 기초 연구로 가루녹차의 농도별 첨가가 요구르트 균주의 증식 및 산 생성에 미치는 영향을 조사하였다. 단독균주의 경우 가루녹차의 첨가 농도를 달리하였을 때 Streptococcus thermophilus와 Lactobacillus casei는 가루녹차 첨가에 의해 증식 효과는 아주 미비하였으나 억제 효과가 나타나지 않았으며, Lactobacillus acidophilus는 배양 9시간부터 가루녹차 첨가구에서 대조구에 비해 높은 균수를 보이며 약간의 생육 촉진 효과를 보였고, 배양 12시간부터 pH가 하락하였으며 적정산도는 상승하였다. 그러나 가루녹차의 첨가량에 따른 생육과 산 생성 정도에 미치는 영향의 차이는 뚜렷하지 않았다. 혼합균주의 경우 단독균주로 배양하였을 때보다 가루녹차에 의한 유산균의 증식이 촉진되며, pH 저하와 적정산도 상승이 뚜렷하였다. 따라서 가루녹차 첨가 기능성 요구르트 제조 시 가루녹차를 0.5%${\sim}$l.0% 첨가하여 유산균을 혼합균주로 사용하는 것이 이들 유산균의 증식에 가장 적합한 것으로 나타났다.