• 한국미생물·생명공학회지
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• 제8권2호
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• pp.103-111
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• 1980

낙과시로 식초를 제조하기 위하여 낙과시의 성분과 식초발효중 주로 관여하는 미생물 및 성분을 조사하여 다음과 같은 결과를 얻었다. 1) 경도는 장준시, 반시, 수시순으로 나타났고 5 ∼6주에 수시, 반시는 급격히 경도가 감소하였다. 2) 총 pectin은 장준시, 반시, 수시순으로 약간 증가하였으며 sduble pectin은 수시, 반시, 장준시 순으로 증가하였다. 3) 총당 환원당은 반시, 장준시, 수시순으로 증가하였으며 5∼6주부터 환원당은 수시와 반시에서 크게 증가하였고 전분은 수시, 장준시, 반시순위이었다가 후에, 큰 차이 없이 감소하였다. 4) 수용성 tannin은 반시, 장준시, 수시순으로 감소하였다. 5) 감식초 발효중 주요미생물을 분리하여 동정하였던 바 효모는 Saccharomyces rouxii C.B.S 726이었고, 초산균은 Gluconobacter oxydans subsp. Suboxydans, Gluconobacter oxydans subsp. oxydans, Acetobacter Pasteurians subsp. Pasteurians, Acetobacter aceti subsp. xylinum으로 동정하였다. 6) 감 식초 발효중 성분변화는 환원당은 일정기간 증가하다가 그 이후는 감소하였고 alcohol은 감소하였으며 산도는 증가하였다.

• 한국연초학회지
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• 제9권1호
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• pp.19-26
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• 1987

KA 101 and Xanthi-Basma were cultivated in Korea and Greece to compare the respective responses to environments on their leaf composition during 1984 and 1985. Cured leaves cultivated in Greece had brighter and greenish color with 2-4 times higher total chlorophyll and carotenoids showing higher contents of total nitrogen, nicotine, petroleum ether extract, volatile acids and neutrals, but crude ash and pH of leaves at top stalk position were lower than in Korean cultured leaves. Xanthi-Basma showed higher contents of nicotine and total nitrogen, but lower contents of reducing sugar than KA 101. There were no difference in crude ash, petroleum ether extract contents and pH of leaves. Among stalk positions, the upper stalk leaves in Greece had higher contents of total nitrogen, protein nitrogen, nicotine, petroleum ether extract and volatile acids but lower contents of reducing sugar than lower ones., whereas the supper stalk leaves in Korea had much higher contents of total nitrogen, protein nitrogen, pH, crude ash, but not higher contents of petroleum ether extract and volatile acid contents than lower stalk position. It suggest that in chemical criteria the better quality leaves are on the upper stalk position in Greece but not the same in Korea probably due to the rainy weather conditions during the later growth stage in Korea.

• 청정기술
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• 제28권1호
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• pp.32-37
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• 2022

Food waste is produced from food factories, food services, and home kitchens. The generated mass reached 5.4 million tons/year in 2020. The basic management technology for such waste has been biological degradation under an anaerobic environment. However, the whole process is intrinsically slow and considerably affected by the inner physicochemical properties of the waste and other surrounding conditions, which makes optimization of the process difficult. The most promising options to counter this massive generation of waste are eco-friendly treatments or recycling. As a preliminary step for these options, attempts were made to evaluate the feasibility and usability of three simulative models based on reaction kinetics. Model (A) predicted relative changes over reaction time for reactant, intermediate, and product. Overall, an increased reaction rate produced less intermediate and more product, thereby leading to a shorter total reaction time. Particle diminishing model (B) predicted reduction of the total waste mass. The smaller particles diminished faster along with the dominant effect of microbial reaction. In Model (C), long-chain cellulose was predicted to transform into reducing sugar. At a standard condition, 48% of cellulose molecules having 10⁵ repeating units turned into reducing sugar after 100 h. Also it was found that the optimal enzyme concentration where the highest amount of remnant sugar was harvested was 1 mg L^-1.

• Korean Chemical Engineering Research
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• 제54권1호
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• pp.70-74
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• 2016

본 연구에서는 창자파래(Enteromorpha intestinalis)로부터 citrate buffer를 사용하여 전처리 조건(고액비, 반응온도, buffer의 pH와 농도)에 따른 전처리 반응과 효소가수분해를 통한 가수분해 수율을 조사하였다. 0.25 M, pH 3.5의 citrate buffer를 이용하여 $140^{\circ}C$에서 60분간 전처리를 수행한 결과, 5.40%의 가수분해 수율을 얻었다. 최종적으로 전처리 반응 후 24시간의 효소 가수분해를 통하여 18.68%의 가수분해 수율을 얻었다. 이 결과는 대조구에 비하여 약 1.81배 증가한 결과이다.

• 한국식품조리과학회지
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• 제11권1호
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• pp.51-57
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• 1995

The effect of milling on the nutrients of raw and parboiled rice grain samples was investigated. Parboiling treatments of choo chung paddy decreased head rice yields and pressure parboiling proved to be more beneficial in reducing white belly rice. Except PP sample mean length/width ratio of parboiled milled rice kernels(8% milling degree) were more larger than raw milled rice and the extent depended on severity of parboil heat treatment. Parboiling had no effect on the protein content of browm rice(0% milling degree) but increased in 4%, 8% milling degree and in PL40 sample. Parboiled rice had a lower fat and the extent depended on degree of milling. Ash content of parboiled brown rice decreasd compared to raw brown rice and generally decreased according to milling degrees were high. Nevertheless, PP, PT40 and PL40 parboiled milled rice samples(0% milling degree) contained more ash than raw milled rice. Parboiling increased total sugar and reducing sugar and increased according to milling degrees were high. Parboiled rice had a high reducing sugar content than raw rice except for PT sample, and more contained as higher milling degree. Total amino acid content of parboiled brown rice increased compared to raw brown rice except for PL40 sample. Parboiled rice of 4% milling degree had a lower total amino acid content and then 8% milling degree had a higher than raw rice. Ca content of parboiled rice was lower than raw rice and tended to have lower as milling degree were high. Parboiled rice of 0 and 4% milling degree had a lower Fe content degree but higher in 8% milling degree. PP and PT40 samples contained more Fe than any other parboiled rice. Parboiled milled rice contained more thiamin than raw milled rice. Rice of milling degree 6% and PL sample contained most thiamin.

• 한국연초학회지
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• 제3권1호
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• pp.20-24
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• 1981

This experiment was carried out to determine the relationships between maturity and content of the chemical components in flue-cured tobacco. The results were as follows : 1) Among the chemical components, the contents of total nitrogen, ammonia nitrogen, total alkaloids, nicotine, total volatile base, petroleum-ether extract, crude fiber, crude ash, water soluble ash, and chlorine decreased significantly, and those of total sugar, reducing sugar, and starch increased as leaf maturity progressed until the stage of ripeness, but, afterwards, a reverse tendency appeared. 2) There was a significant relationship between maturity and the contents of chemical components, such as total nitrogen, protein nitrogen, ammonia nitrogen, total volatile base, and the correlation coefficients of them were -0.743, -0.789, -0.797, and -0.642, respectively.

• Journal of Ginseng Research
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• 제4권1호
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• pp.88-95
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• 1980

Red ginseng was extracted with water and analyzed for yield, saponin, pectin and other chemical composition. It was found that: (1) The total solid content in extract after 6 times of extraction was 46.8%,: including 13.6% of centrifugal residue; (2) 83.7% of total extractable solids and 86% total saponin was extracted after the initial three runs of extraction. (3) No significant changes were observed in HPLC pattern of extracted saponins over a range of extractions; (4) The ratio of centrifugal residue to total solids increased as the number of extractions increased; (5) The ratios of fat, protein, reducing sugar and pectin contents decreased with repeating extraction while those of crude fiber, total sugar and 35% alcohol insoluble residue increased when they were compared with total solids.

• 한국가정과학회지
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• 제5권2호
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• pp.45-54
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• 2002

Packaged Backsulgi cooked by steam/convection oven and then rapidly chilled was examined by research of microbiological test and sensory evaluation while storing them at the temperatures of 3$^{\circ}C$ and 3$0^{\circ}C$ for 0, 2, 4, 6, 10 days . The pH and reducing sugar content were seemed to change little at 3$^{\circ}C$. However the pH was rapidly reduced until 4 days and then decreased a little at 3$0^{\circ}C$, the reducing sugar content was inclosed little by little. In the microbiological test, any microbial growth in total aerobic, psychrophilic, anaerobic, spore forming bacteria, yeast and molds was not observed until 10 days at 3$^{\circ}C$, but microbial changes of aerobic, psychrophilic and anaerobic bacteria increased to 6 logCFU/g until 10 days at 3$0^{\circ}C$. However microbial changes of them decreased from 6 logCFU/g to 5 logCFU/g. As a result of the sensory evaluation, appearance, taste, color, softness, chewiness and overall Quality were significantly decreased during storage times(p<0.05), but scores of taste and overall quality on 6th days were 7.38${\pm}$1.06, 7.00${\pm}$0.93. Therefore we concluded that there was no problem about stability of storage 6 days at 3$^{\circ}C$.

• Korean Chemical Engineering Research
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• 제53권4호
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• pp.478-481
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• 2015

본 연구는 거대 녹조류인 창자파래(Enteromorpha intestinalis)를 대상으로 고체 산촉매를 사용하여 환원당을 생산하고자 하였다. 가수분해 반응은 고액비, 촉매량, 반응온도와 반응시간을 대상으로 최적화하였다. 결과적으로 액/고비 7.5, 반응온도 $140^{\circ}C$, 촉매량 15%, 그리고 반응시간 2 hr에서 7.74 g/L의 환원당을 얻었다. 반면에 단지 0.13 g/L의 5-HMF만이 생성되었다. 이로부터 고체 산촉매를 이용한 해양 바이오매스 자원의 가능성을 확인하였다.

• 한국식품조리과학회지
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• 제21권1호
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• pp.103-109
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• 2005

김치의 이화학적 지표에 따른 신맛과 종합적인 기호도간의 상관관계를 알아보기 위해 $5^{\circ}C$, $10^{\circ}C$, $20^{\circ}C$로 나누어 발효과정 중의 pH, 총 당함량, 총균수 및 젖산균수를 분석하였다. pH와 신맛의 관계에서 $10^{\circ}C$와 $20^{\circ}C$에서는 신맛과 pH의 변화 양상이 거의 반비례하였으나 $5^{\circ}C$는 그에 비해 반비례 경향이 낮았다. 환원당 함량과 신맛의 관계에서 산도 $0.8\%\~1.0\%$까지는 신맛과 환원당 함량이 서로 반비례하였고, 종합적인 기호도가 가장 높을 때의 환원당 함량은 $10^{\circ}C$와 $20^{\circ}C$는 거의 비슷하였고, $5^{\circ}C$는 그에 비해 환원당 함량이 높았다 총균수의 경우 $5^{\circ}C$ 숙성김치에서 총균수와 신맛의 최고점이 일치하지 않았으나 $10^{\circ}C$와 $20^{\circ}C$ 숙성김치에서는 최고점이 일치하였으며, 이후 점차 감소하는 경향을 보였다. 또한 종합적인 기호도가 가장 높은 때의 총균수는 $10^{\circ}C$ 숙성김치가 가장 높았고, $5^{\circ}C$와 $20^{\circ}C$ 숙성김치는 큰 차이를 보이지 않았다. 젖산균의 경우, $5^{\circ}C$ 숙성김치에서는 젖산균과 신맛의 최고점이 일치하지 않았으나 $10^{\circ}C$와 $20^{\circ}C$ 숙성김치에서 일치함을 보였다. 저온과 고온 숙성시 신맛과 숙성지 표와의 상관관계에서 $5^{\circ}C$ 숙성김치의 신맛은 산도와 매우 유의적인 상관관계를 보였고, pH와 미생물 균수와는 양의 상관관계를 보였으나 유의적인 차이($\alpha$=$0.5\%$)는 보이지 않았고, $10^{\circ}C$와 $20^{\circ}C$ 숙성김치에서 신맛은 모두 숙성지표와 매우 유의적인 상관관계를 보였다.