• Title/Summary/Keyword: fermentation control

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Effect of Chitosan on Storage Stability of Nabak Kimchi (나박김치의 저장성 향상을 위한 Chitosan 첨가의 효과)

  • 전순실
    • Korean Journal of Plant Resources
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    • v.11 no.1
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    • pp.111-117
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    • 1998
  • The effect of chitosan on physicochemical and organoleptic properties of Nabak kimchi was studied during fermentation at 2$0^{\circ}C$ . Viscosity of the juice of Nabak kimchi added with chitosan was lower than that of control group. The viscosity was gradually increased during storage period, especially from 5 days to ,7 days of storage. Initial pH was higher in control group than inchitosan groups. The pH of controlgroup decreased rapidly during 4 days of storage. The pH of chitosan groups was slightly increased during the first 3 days of storage and decreased thereafter. Acidity was rapidly increased from 3 to 5 days. Reducing sugar contents increased up to 3 days and decreased thereafter. Acidity was rapidly increased from 3 to 5 days. Reducing sugar contents increased upto 3 days and decreased therafter. Glutamic acid, alanine, threonine, aspartic acid, proline and valine were the major free amino acids, and as the fermentation preceeded they were increased gradually. There were signigicant differences in saltiness, sourness and aged odor in sensory evaluation of Nabak kimchi solution during fermentation at 2$0^{\circ}C$.

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Study on the Deacidification of Wine Made from Campbell Early (Campbell Early를 이용하여 만든 포도주의 산도 감소에 관한 연구)

  • Lee, Ju-Kyung;Kim, Jae-Sik
    • Korean Journal of Food Science and Technology
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    • v.38 no.3
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    • pp.408-413
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    • 2006
  • The domestic grape cultivar Campbell Early has high levels of both malic acid and tartaric acid. Therefore, the processing of wine made from Campbell Early must include decreasing the acidity. Six different methods were tested for reducing excess acidity: traditional vinification, precipitation, cold stabilization, malolactic fermentation (MLF), carbonic maceration and cold fermentation. Wines had higher pH values and lower total acidity than control after all the processing methods except cold stabilization. With regard to the measured organic acid content, the control contained 2,927 ppm tartaric acid, 2,421 ppm malic acid and 486 ppm lactic acid, but the precipitated wine contained 2,346 ppm tartaric acid. The MLF wine contained 828 ppm malic acid and 2,394 ppm lactic acid. Wine after carbonic maceration contained 792 ppm malic acid and cold fermentation decreased the organic acid contents in general. Sensory analysis showed that the carbonic maceration and precipitation methods resulted in wines that were excellent in color, flavor, taste and overall preference.

The Effect of Low Molecular Weight Chitosans on the Characteristics of Kimchi during Fermentation (저분자 chitosan이 배추김치 모델시스템의 보존성에 미치는 영향)

  • Kim, Kwang-Ok;Moon, Hyung-Ah;Jeon, Dong-Won
    • Korean Journal of Food Science and Technology
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    • v.27 no.3
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    • pp.420-427
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    • 1995
  • This study was conducted to investigate the preservative effect of low molecular weight chitosans on kimchi(2% salt concentration) during fermentation at $20^{\circ}C$. The pH and total acidity of control kimchi were lower and higher, respectively than those of kimchi samples containing chitosan. Reducing sugar content tended to be lower in control kimchi than in kimchi samples containing chitosan until 6 days of fermentation. Malic acid content was lower in control kimchi than in kimchi samples containing chitosan until 4 days of fermentation. Succinic acid content was higher in control kimchi than in kimchi samples containing chitosan at the 2 days of fermentation. Content of lactic and acetic acid also was higher in control kimchi than in kimchi samples containing chitosan at the 4 days of fermentation. The number of total microorganisms and those of microorganisms of Leuconostoc genus and Lactobacillus plantarum were higher in control kimchi than in kimchi samples containing chitosan. The number of microorganisms of Leuconostoc genus was lower in kimchi samples containing chitosan with the lower molecular weight chitosan than those with the higher molecular weight chitosan. Intensity of sensory sour taste and staled flavor were higher in control kimchi than in kimchi samples containing chitosan. There was not much difference in sensory firmness among kimchi samples, but control kimchi was evaluated slightly weaker than kimchi samples containing chitosan. Off-flavor was evaluated as weak in all the kimchi samples.

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On-line Induction of Fermentation with Recombinant Cells: Part II. Control Algorithm and Software Development (유전자 재조합 세포 발효의 온.라인 유도 : 제 2부. 제어 알고리즘 및 소프트웨어 개발)

  • 이철균;최차용
    • KSBB Journal
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    • v.4 no.3
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    • pp.203-207
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    • 1989
  • Software for the on-line feedback control of such variables as DO and temperature was developed and tested successfully for a real fermentation system. Several aspects like Pl, PID, DSC, and DDC were incorporated into the algorithm. Any kind of on-line computer control system can be successfully implemented without much difficulty.

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Effect of Calcium-Sources and Preservatives on the Changes of Vitamins during Kimchi Fermentation (칼슘급원 및 보존료 첨가가 김치 발효중 비타민 함량변화에 미치는 영향)

  • 이혜준
    • Journal of the Korean Home Economics Association
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    • v.26 no.1
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    • pp.51-59
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    • 1988
  • In the present study, an attempt was made to observe the effect of calcium-sources and preservatives on Kimchi fermentation. After pre-fermentation at room temperature for 16 hours, each Kimchi was stored at 4$^{\circ}C$. Changes of vitamin contents(vitamin C, thiamin, riboflavin and $\beta$-carotene) during the fermentation of Kimchi were determined. It was also attempt to relate the fermentation of Kimchi with the changes in chemical and organoleptic characteristics, such as pH, total acidity and reducing sugar. The findings were summarized as follows; 1. During Kimchi fermentation, the pH decreased steady and total acidity increased slowly in the follow order: K-Sorbate+acetic acid, k-Sorbate, Ca-Lactate and Control. the lower of pH and the higher of total acidity, the less of reducing sugar was remained. 2. changes of total vitamin C and reduced ascorbic acid contents during the Kimchi fermentation did not differ significantly from each other. At the begining of fermentation, Kimchi samples contained 20~25mg/100g of total vitamin C and 5~14 mg/100g of reduced ascorbic acid. In the final stage, however, 15~19 mg/100g of total vitamin C and 1~3 mg/100g of reduced ascorbic acid were remained. 3. The contents of thiam in and riboflavin were 30 to 42 meg/100g and 50 to 67 meg/100g at the initial stage, respectively. They increased with the degree of maturity (approximately 2 times of the content of the initial stage) and then gradually decreased. The content of $\beta$-carotene was found to be decreased with the degree of maturity. 4. The results of sensory evaluation indicated that Kimchi added with Ca-Carbonate, Ca-Carbonate+acetic acid and Ca-lactate were better than Control.

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Characteristics of Lactic Acid Fermentation of Black Raspberry Juice Using the Lactobacillus plantarum GBL17 Strain (Lactobacillus plantarum GBL17 균주를 이용한 복분자 유산발효 특성)

  • Ryu, Eun-Hye;Yoon, Hae-Hoon;Jung, Ji-Hye
    • Korean journal of food and cookery science
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    • v.31 no.6
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    • pp.773-780
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    • 2015
  • Lactic acid fermentation of black raspberry (Rubus occidentalis) juice was carried out by using the Lactobacillus plantarum GBL17 strain. The sterilized black raspberry juice was fermented using the L. plantarum GBL17 strain at $30^{\circ}C$ for 72 hours after which the total acidity increased and the pH value decreased. In addition, the highest total acidity content (2.38%) was reached, the lowest pH value (3.22) was observed, and the sugar content decreased by $9.8^{\circ}Brix$ after the 72 hour fermentation. The number of viable cells rapidly increased up until 24 hours, after which it gradually decreased. HPLC analysis of the organic acids showed 14.51 mg/g of lactic acid content in the fermented black raspberry juice, which was not detected in the non-fermented black raspberry juice (control). The content of fructose and glucose slightly decreased after fermentation. The total polyphenol and flavonoid contents of the fermented black raspberry juice increased significantly after fermentation. The DPPH radical scavenging activity of fermented black raspberry juice (70.92%) was higher than that of the control (62.96%). After lactic acid fermentation, there was no significant increase in ABTS radical scavenging activity. These results confirm that lactic acid bacteria, such as L. plantarum GBL17, showed generally higher activities with a potential as a functional beverage.

Optimization of the Medium and Fermentation Conditions with Erythritol Producing Moniliella suaveolens var. nigra (에리스리톨 생산 균주인 Moniliella suaveolens var. nigra를 이용한 배지 및 발효조건의 최적화)

  • Choe, Byeong-Uk;Park, Hong-U
    • KSBB Journal
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    • v.14 no.5
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    • pp.628-632
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    • 1999
  • Optimization of the medium and fermentation conditions for erythritol production has been studied. We have found that the optimal carbon source was glucose at the concentration of 400 g/L. The optimal temperature was 3$0^{\circ}C$ with excessive aeration. Improved erythritol productivity was achieved by reducing the yeast extract from 5 g/L to 3g/L while adding 2.7 g/L urea, 1.79g/L $K_2HPO_4, and 0.18g/L MgSO$_4$. 7$H_2O. The erythritol productivity increased from 0.747 g/L/h to 1.071 g/L/h and the yield increased from 31.4% to 45.2%. The byproduct glycerol was reduced from 96.6g/L to 45.7g/L as well. We have performed 5L fermentation with and without the pH control. The erythritol productivity with the pH control was about 30% lower than that without pH control. Excessive foaming of 5L fermentation has been observed during fermentation.

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Changes of Chemical Components of Fermented Tea during Fermentation Period (미생물을 이용한 후발효차의 발효기간별 화학성분 변화)

  • Kim, Yong-Shik;Choi, Goo-Hee;Lee, Kyung-Haeng
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.39 no.12
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    • pp.1807-1813
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    • 2010
  • To manufacture the fermented tea with hygienic quality, green tea was fermented using Bacillus subtilis, Saccharomyces cerevisiae and Lactobacillus bulgaricus and chemical composition and sensory changes were evaluated during fermentation period. The lightness of the fermented samples decreased; in contrast, redness and yellowness increased. Especially, the color change of the fermented tea using B. subtilis was higher than those of control and other samples with different microorganisms during fermentation period. Chlorophyll contents were decreased by similar level regardless of fermentation treatments. The fastest decrease of total catechins contents were found in the tea fermented with B. subtilis and significantly reduced by increase of fermentation period. However, total catechin contents of the tea fermented by L. bulgaricus were not decreased. The caffeine contents of the microbial fermented teas were more decreased than that of control, even though the decrease was slight. Sensory panelists preferred the tea fermented by B. subtilis to those of control or other fermentation treatment.

Effects of L-tryptophan, Fructan, and Casein on Reducing Ammonia, Hydrogen Sulfide, and Skatole in Fermented Swine Manure

  • Sheng, Q.K.;Yang, Z.J.;Zhao, H.B.;Wang, X.L.;Guo, J.F.
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.8
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    • pp.1202-1208
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    • 2015
  • The effects of daily dietary Bacillus subtilis (Bs), and adding L-tryptophan, fructan, or casein to fecal fermentation broths were investigated as means to reduce the production of noxious gas during manure fermentation caused by ammonia, hydrogen sulfide ($H_2S$), and 3-methylindole (skatole). Eighty swine ($50.0{\pm}0.5kg$) were equally apportioned to an experimental group given Bs in daily feed, or a control group without Bs. After 6 weeks, fresh manure was collected from both groups for fermentation studies using a $3{\times}3$ orthogonal array, in which tryptophan, casein, and fructan were added at various concentrations. After fermentation, the ammonia, $H_2S$, L-tryptophan, skatole, and microflora were measured. In both groups, L-tryptophan was the principle additive increasing skatole production, with significant correlation (r = 0.9992). L-tryptophan had no effect on the production of ammonia, $H_2S$, or skatole in animals fed Bs. In both groups, fructan was the principle additive that reduced $H_2S$ production (r = 0.9981). Fructan and Bs significantly interacted in $H_2S$ production (p = 0.014). Casein was the principle additive affecting the concentration of ammonia, only in the control group. Casein and Bs significantly interacted in ammonia production (p = 0.039). The predominant bacteria were Bacillus spp. CWBI B1434 (26%) in the control group, and Streptococcus alactolyticus AF201899 (36%) in the experimental group. In summary, daily dietary Bs reduced ammonia production during fecal fermentation. Lessening L-tryptophan and increasing fructan in the fermentation broth reduced skatole and $H_2S$.

Effect of Added Doenjang (Soybean Paste) on the Kimchi (Fermented Korean Cabbage) Fermentation (된장 첨가가 김치 발효에 미치는 영향)

  • Lim, Yong-Suk
    • Food Science and Preservation
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    • v.15 no.1
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    • pp.139-143
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    • 2008
  • The potential use of Doenjang in place of salted-fish juice as an ingredient in Kimchi fermentation was examined, to improve Kimchi qualities such as flavor and taste. Quality characteristics were monitored during progressive fermentation of Kimchi with Doenjang (KD) at 7 d intervals for 28d at constant temperature $(10^{\circ}C)$. The data showed that the pH of KD was somewhat lower than that of the control as fermentation progressed. The titratable acidity in KD was linearly proportional to the pH change. Both the growth of lactic acid bacilli and total bacteria in Kimchi were inhibited in KD compared to control. In terms of color, the L, a, and b values of KD were all lower than those of control. In sensory evaluation, the taste, flavor, color, and overall acceptability of the new form of Kimchi were increased significantly by addition of 5 % (w/w) Doenjang (p<0.05). All data indicated that the color and taste properties of KD were improved by addition of Doenjang during fermentation.