• Food Science and Biotechnology
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• 제18권5호
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• pp.1083-1090
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• 2009

Fermentation of wort was investigated with an ultimate goal to develop a fermented beverage rich in prebiotics and functional ingredients as well as desirable in flavors. Wort was fermented with Leuconostoc citreum HJ-P4 originated from kimchi and subjected to sensory descriptive analysis. L. citreum HJ-P4 produced various organic acids (e.g., lactic acid, acetic acid) as well as functional sugars (e.g., mannitol, panose) during wort fermentation. The concentration and ratio of lactic acid and acetic acid were significantly influenced by roasting conditions of malts used for wort preparation and aeration conditions during fermentation. The concentration of mannitol and panose varied depending on the sucrose content of wort and aeration conditions. Sensory characteristics of the fermented worts were clearly differentiated according to the roasting conditions of malts used for wort preparation and aeration conditions during fermentation. These results indicate that metabolite concentration of fermented wort and its sensory properties can be manipulated with roasting conditions of malts and fermentation conditions.

• Biotechnology and Bioprocess Engineering:BBE
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• 제8권5호
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• pp.269-278
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• 2003

Gibberellic acid (GA$_3$) is a commercially important plant growth hormone, which is gaining much more attention all over the world due to its effective use in agriculture and brewing industry. Industrially it is produced by submerged fermentation technique using Ascomycetous fungus Gibberella fujikuroi. Solid state and immobilized cell fermentation techniques had also been developed as an alternative to obtain higher yield of GA$_3$. This review summarizes the problems of GA$_3$ fermentation such as production of co-secondary metabolites along with GA$_3$, substrate inhibition and degradation of GA$_3$ to biologically inert compound gibberellenic acid, which limits the yield of GA$_3$ in the fermentation medium. These problems can be overcome by various bioprocessing strategies e.g. two - stage and fed batch cultivation processes. Further research on bioreactor operation strategies such as continuous and / or extractive fermentation with or without cell recycle / retention system need to be investigated for improvement in yield and productivity. Down stream processing for GA$_3$ isolation is also a challenge and procedures available for the same have been critically evaluated.

• 한국식품과학회지
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• 제38권3호
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• pp.408-413
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• 2006

본 연구에서는 국내산 포도주의 감산 연구를 위해 Campbell Early를 이용하여 control, precipitation, cold stabilization, MLF, carbonic maceration, cold fermentation과 같이 6가지 다른 방법으로 산도 감소 효과를 실험해 보았다. 6가지 방법으로 제조한 포도주가 $4-5^{\circ}Brix$의 당도와 6.8-7.7%의 알코올 함량을 나타냄으로써 산도 감소를 위해 발효 방법을 달리해도 정상적인 발효가 진행되었음을 확인할 수 있었다. 그리고 숙성 중에 pH와 총산, 유기산 함량을 측정하여 감산의 정도를 알아본 결과 cold stabilization을 제외하고는 각 포도주들이 control보다 pH는 증가하고 총산은 감소하였다. 특히 carbonic maceration은 총산이 0.42 g/100 mL로 산도 감소에 효과적인 방법임을 확인할 수 있었다. 이는 HPLC를 이용하여 측정한 유기산 함량에서도 알 수 있었다. Control의 tartaric acid가 2,928 ppm인 반면 precipitation은 2,346 ppm으로 precipitation으로 인해 tartaric acid가 감소했음을 확인할 수 있었다. Control의 malic acid는 2,421 ppm, lactic acid는 486 ppm이었으나 MLF의 경우는 malic acid가 828 ppm으로 감소했고, lactic acid는 2,394 ppm으로 증가한 것을 확인할 수 있었다. 그리고 carbonic maceration은 malic acid가 993 ppm으로 눈에 띄게 감소하였고, cold fermentation은 유기산 함량이 전체적으로 감소한 것을 확인할 수 있었다. 산도가 감소한 포도주의 품질을 평가하기 위해 총페놀 함량, hue, 색도, 관능검사를 실시한 결과 산도 감소 효과가 우수한 precipitation과 carbonic maceration 방법으로 제조한 포도주가 품질 평가에서도 우수하게 나타났다. 이로써 본 연구에서는 carbonic maceration과 precipitation이 Campbell Early 포도주에 적합한 감산 방법이며, 제조한 포도주도 선명하고 진한 붉은색을 가지며, 포도향이 풍부하고, 신맛이 강하지 않음을 확인할 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제12권4호
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• pp.525-530
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• 1999

Prior to ensiling Rhodesgrass (RG) and Italian ryegrass (lRG) were treated with lactic acid bacteria (LAB) or with LAB+cellulases to compare their fermentation characteristics and chemical compositions. LAB (Lactobacillus casei) was added to all ensiling materials (except the untreated control) of RG and IRG at a concentration of $1.0{\times}10^5\;cfu.g^{-1}$ fresh forage. The enzymes used were Acremoniumcellulase (A), Meicelase (M) or a mixture of both (AM). Each enzyme was applied at levels of 0.005, 0.01 and 0.02 % of fresh forage. The silages with each treatment were incubated at 20, 30 and $40^{\circ}C$ and stored for about 2 months. While no marked differences were found between the RG and IRG silages with various treatments on dry matter (DM), volatile basic nitrogen (VBN) and water soluble carbohydrate (WSC) contents, there were significant differences in pH value, and lactic acid and butyric acid contents. LAB inoculation did not affect the fermentation characteristics of either the RG or IRG silages. The combined treatments of LAB+cellulases improved the fermentation quality of both the RG and IRG silages as evidenced by the decrease in pH value and increase in lactic acid content. Increasing the amount of added cellulase resulted in a decrease in pH value and an increase in lactic acid content in both the RG and IRG silages. Cellulases A and AM had a greater effect than cellulase M on the fermentation quality of the RG and IRG silages. Incubation temperatures of 30 and $40^{\circ}C$ appeared to be more appropriate environments for stimulating good fermentation than $20^{\circ}C$.

• 한국식품과학회지
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• 제32권1호
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• pp.125-131
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• 2000

고추장의 품질 향상 및 제품 다양화를 목적으로 메주, 고오지 및 메주와 고오지의 혼용으로 담금한 고추장의 숙성과정 중 품질은 아래와 같다. 고추장 숙성과정 중 수분은 $53.4{\sim}66.5%$, 식염 $8.3{\sim}10.1%$, 조단백질 $8.3{\sim}19.3%$, pH $4.6{\sim}5.4$의 범위였다. 아미노태질소는 숙성 중 증가하여 150일에 $230{\sim}270mg%$로 나타났고 담금 직후에는 혼용고추장에서, 숙성 30일 이후는 고오지 고추장에서 높았다. 환원당은 숙성 60일에 $15.0{\sim}19.5%$로 최대함량을 보였다. 고추장의 아미노산 함량은 glutamic acid가 $1.38{\sim}3.66%$로 아미노산 중 함량이 가장 높았고 이외 aspartic acid, leucine, arginine, alanine, phenylalanine의 함량이 높은 편에 속하였다. 색도의 밝기는 30일까지 혼용고추장에서, 이후는 메주 고추장에서 높았으며 적색도는 60일까지 메주 고추장에서, $90{\sim}120$일에는 고오지 고추장에서 높았다.

• Applied Biological Chemistry
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• 제28권4호
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• pp.226-232
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• 1985

재래식메주의 발효과정에 있어서 지질 및 지방산 조성의 변화를 체계적으로 규명하기 위해 silicic acid column chromatography를 이용하여 중성지질, 당지질, 인지질은 분리하였으며 gas liquid chromatography를 이용하여 지방산 함량은 조사한 결과는 다음과 같다. 1. 침지한 콩과 삶은콩으로부터 얻은 조지질의 분획은 중성지질이 각각 92.47%, 92.35%이었으며, 인지질 및 당지질이 4.64%, 4.88%로 각각 나타났나. 발효과정중 중성지질은 80.59%까지 감소했으며, 당지질과 인지질의 함량은 증가하였다. 2. 침지한 콩과 삶은콩의 비극성 지질에서 triglyceride함량은 89.66%, 87.83%로 주류를 이루었고, sterol ester, free fatty acid, diglyceride 및 sterol이 발효과정중 그 함량이 증가한 반면, triglyceride는 크게 감소했다. 3. 침지한 콩과 삶은콩에서, 조지질, 증성지질, 당지질, 인지질의 지방산 조성은 linoleic acid $54{\sim}58%$, oleic acid $22{\sim}20%$, palmitic acid $10{\sim}12%$, stearic acid $3{\sim}5%$였으며 myristic acid는 trace로 나타났다. 그러나 발효과정 중 당지질에서 myristic acid가 발효 2주때 부터 나타나며 약 2%정도를 유지했다. 4. 메주 발효기간 동안 지방산 함량의 변화는 palmitic acid가 2주째 부터 점차 감소했다. oleic acid와 linoleic acid는 약간씩 감소했으며, linolenic acid는 인지질에서 크게 감소한 반면, 조지질, 중성지질, 당지질에서는 약간씩 증가했다. 5. 발효기간 동안 당지질 분획에서 myristic acid가 증가하였으며, 지방분해효소의 활성은 3주째 최대치를 보였다. palmitic acid, stearic acid는 3주째 까지 증가한 후 차차 감소하였고 linoleic acid는 1주째 부터 6주까지 점차 증가하였다.

• 한국식품저장유통학회지
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• 제6권2호
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• pp.233-238
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• 1999

단감과 떫은감의 2단계 발효과정에 의해 제조된 감식초의 품질 평가를 위해 제조중 성분 변화를 검토하였다. 유리당은 단감의 경우 glucose 6.60, fructose 6.12 및 sucrose 1.74%이었으며, 떫은감의 경우에는 각각 5.63, 5.21, 0.62%로, glucose 함량이 가장 높았다. 발효기간이 경과함에 따라 유리당의 함량은 점차 감소하는 경향을 나타내었으며, 특히 glucose의 감소가 급격히 감소하였다. 감식초의 유기산은 단감과 떫은감 모두 acetic acid 함량이 가장 높았고, galacturonic, malic, citric, ascorbic acid도 미량 검출되었다. 감식초의 알콜발효시 알콜성분은 acetaldehyde, methanol, ethanol, iso-propylalcohol, n-propylalcohol, iso-butylalcohol 및 iso-amylalcohol 등 7종이 분석되었고, 알콜발효 4일까지는 모두 증가하는 경향이었으나 5일째에는 ethanol을 제외한 성분들은 다소 감소하는 경향이었다. 유리아미노산의 함량은 단감식초에서 떫은감식초에서보다 약간 높았고, 휘발성 성분은 단감의 경우에 알콜발효 후 7종, 초산발효 후 9종, 떫은감에서는 알콜발효 후 6종, 초산발효 후에는 9종의 성분이 분석되었다.

• 한국농촌생활과학회지
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• 제10권2호
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• pp.60-70
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• 1999

Changes in the nutritional components of Toha-jeot, salt-fermented Toha shrimp (Caridina denticulata denticulata $D_EH_{AAN}$), which was salted with a low-salt group of 15% sodium chloride (L), a high-salt group of 23% sodium chloride (H), a 50% conventional soybean sauce group (S) during long fermentation were investigated. These three groups were refrigerated at ${4\pm}1^{\circ}C$ and then taken out for analysis at three month intervals during 9 month. Even in the process of a long fermentation, the moisture containment of Toha-jeot in group L and S is 76.0~73.6% and in group H it is 70.0%, which are similar in all three groups. In case of the salinity, there was no change in groups L, H but it was lowered in group S during the fermentation. In all groups there was no change of pH. The free amino acid contents in Toha-jeot, of which ornitine, glutamic acid, leucine, alanine, lysine and valine occupy the majority, in order of abundance, increased gradually up to six months of fermentation and decreased by nine months. But free amino acid contents of S group increased continuously during the fermentation process. Hypoxanthine was altered almost among other nucleotides. ATP was not detected, IMP and inosine had disappeared after the six months for mentation. ADP was not detected after the nine months fermentation. Monoene, polyene and n-3 fatty acids were increased and saturated fatty acids were decreased in L and H groups. However, no changes of fatty acid contents in S group during fermentation were showed. The fatty acid contents of three groups, of which $C_{18:1},\;C_{16:0},\;C_{16:1}$ and $C_{20:5}$ occupy the majority, Mineral content of Toha-jeot is mainly consisted of Na, Ca, K and Mg. In the Hunter values, the redness of L group was superior to that of other groups.

• 한국식품영양학회지
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• 제8권3호
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• pp.184-191
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• 1995

This study was designed to investigate the changes In chemical characteristics of traditional kochujang increase in fermentation time, whereas that of total sugar decreased rather rapidly during aging of meju. Amino nitrogen content of meju Increased sharply up to 40 days of fermentation and then decreased there after On the other hand, ammoniacle nitrogen content continued to increase with increasing aging time. Initially, maltose was the most abundant free sugar, but was later replaced by glucose or fructose as the fermentation proceeded. Among non-volatile organic acids, pyroglutamic acid was present at an appreciably other organic acids did not change considerably during fermentation. The total free amino acid content Increased up to 40th day of aging and then decreased thereafter The was the most abundant amino acid followed in decreasing order by Try and Glu in meju fermented for 40 days.

• Preventive Nutrition and Food Science
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• 제7권1호
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• pp.37-42
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• 2002

Factors affecting the production of bacterial cellulose and organic acids in Kombucha fermentation were investigated. Kombucha was obtained by the fermentation (for 12 days at 3$0^{\circ}C$) of the green/black tea extract, supplemented with 10% white sugar, using an Oriental tea fungus as starter. Hitgher initial pH increased acid production with decreased cellulose production. With a cellulose pellicle or tea fungus broth as a starter, a 1~3 mm thick cellulose layer developed as a top layer every four days, and was removed subsequently while continuing fermentation. Addition of 30 mL tea fungus broth (13%, v/v) in Kombucha fermentation resulted in maximum production of a cellulose pellicle, indicating weak acid production. Yield of cellulose production at an early stage of fermentation was also higher when Kombucha was inoculated with a cellulose pellicle. In fact, addition of 1% (v/v) alcoholic beverage in the Kombucha fermentation activated the cellulose production, coupled with four times higher acid production.