• Title/Summary/Keyword: times of fermentation

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Quality of Alaska Pollack Theragra chalcogramma Sikhae after Fermentation for Different Times (변온숙성에 의한 명태(Theragra chalcogramma)식해의 품질유지)

  • Jeong, Eun-Jeong;Kim, Hun;Cha, Yong-Jun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.48 no.3
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    • pp.293-300
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    • 2015
  • We sought to extend the shelf-life of Alaska pollack Theragra chalcogramma sikhae while maintaining quality. We compared the chemical, microbiological, and organoleptic characteristics of sikhae prepared under four different conditions. Control fish were fermented at ambient temperature ($21{\pm}2^{\circ}C$); other samples were stored at $5^{\circ}C$ after fermentation at ambient temperature for 36 h (A1), 60 h (A2), and 84 h (A3). Volatile basic nitrogen and amino-nitrogen levels, and total acidity increased with fermentation time in all samples, but the pH fell, attaining a relatively lower level in the control than in other samples. Over 90% of all viable cells were lactic acid-producing bacteria; this proportion did not change significantly during fermentation. In terms of texture, only hardness was affected by fermentation. The hardness of the control fell more rapidly than did that of the other samples. In terms of sensory evaluation (the acceptance test and quantitative descriptive analysis [QDA]), A2 was superior to other samples after fermentation for different times; A2 maintained limited salability (6 points on the relevant index) for up to 17 days of storage.

Aerobic Liquid Fermentation of Residual Food Waste by Thermophilic Bacteria (고온세균을 이용한 남은 음식물의 호기적 액상발효)

  • Ryu, Seung-Yong;Park, Myoung-Ju;Kim, So-Young;Lee, Ki-Young
    • Journal of the Korea Organic Resources Recycling Association
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    • v.10 no.3
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    • pp.126-131
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    • 2002
  • For the probiotic feed production from residual food waste, aerobic liquid fermentation was conducted by thermophilic bacteria. 11 Strains of bacteria were isolated from several soil sources and residual food waste. Screening was carried by shaking incubator for the separation of thermophilic strain at $55^{\circ}C$. The isolated strains were tested for enzyme activities such as ${\alpha}$-amylase and protease. 6 Bacterial strains were chosen and were adapted by repeated fermentation processes in food waste substrate. The viable cell count of them at final fermentation stages were shown as $3-7{\times}10^9/ml$ in 2L-jar fermenter. Among them B3, B6 showed higher enzyme activity. By the mixed fermentation of B3, B6 and Bacillus stearothermophilus, the highest viable cell count reached to $1.4{\times}10^{10}/ml$ in 8 hours.

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The Effect of Green Tea Extracts on the Fermentation Properties of Polyphenol-Enriched Beers (녹차 추출물을 첨가한 polyphenol 강화 맥주의 발효 특성에 대한 연구)

  • Yom, Heng-Cherl
    • Journal of the Korean Home Economics Association
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    • v.46 no.3
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    • pp.49-55
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    • 2008
  • The purpose of this study was to investigate the effects of green tea extracts (GTE) on the fermentation properties of polyphenol-enriched beers. As such, the formation patterns of tannoid in beer with GTE were investigated at 3 different infusion times, while the ale and the lager beers fortified with GTE were analyze to ascertain effects on gravity, pH, yeast viability, total polyphenol, and tannoid during fermentation period. The results were as follows: 1) The formation of tannoid in beer with GTE in the tannometer; In reaction of GTE with polyvinylpyrrolidon (PVP), control lager beer peaked in the formation of tannoid at $70\;{\sim}\;80\;mg$ of PVP, the 1st extract exceeded the detection limit, the 2nd extract at $170\;{\sim}\;180\;mg$, while the third extract at $150\;{\sim}\;160\;mg$ of PVP. The GTE were slow in reacting with PVP, and their formation patterns were different from those of polyphenols from barley and hop. 2) Ale fermentation; The final alcohol content was 9.25% (ABV). The addition of GTE increased the yeast viability after 2 days and finally reached 52.3% from 30.9%. Total polyphenol in GTE beer increased by 1.5 times (p < .05). However, its tannoid contents increased by 6.4 times. 3) Lager fermentation; The final alcohol content was 5.93% (ABV). The effect of GTE on lager beer was minimal for all variables. However, total polyphenol of GTE beer increased by 1.4 times (p < .05). Its tannoid increased by 3.3 times (p < .05).

Effect of additives and filling methods on whole plant corn silage quality, fermentation characteristics and in situ digestibility

  • Jiao, Ting;Lei, Zhaomin;Wu, Jianping;Li, Fei;Casper, David P.;Wang, Jianfu;Jiao, Jianxin
    • Animal Bioscience
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    • v.34 no.11
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    • pp.1776-1783
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    • 2021
  • Objective: This project aimed to evaluate the effects of both different additives and filling methods on nutritive quality, fermentation profile, and in situ digestibility of whole plant corn silage. Methods: Whole plant corn forage harvested at 26.72% dry matter (DM) was chopped and treated with two filling methods, i) fill silos at one time (F1), ii) fill silos at three times (F3), packing samples into one/three silo capacity at the first day, another one/three capacity at the second day, then one/three at the third day, three replicates. For each replicate, samples were treated with three additives, i) control (CTRL, no additive), ii) Sila-Max (MAX, Ralco Nutrition Inc., Marshall, MN, USA), and iii) Sila-Mix (MIX, Ralco Nutrition Inc., USA). With three replicates of each secondary treatment, there were nine silos, 54 silos in total. Each silo had a packing density of 137.61 kg of DM/m3. All silos were weighed and stored in lab at ambient temperature. Results: After 60 d of ensiling, all items showed good silage fermentation under MAX filled one time or three times (p<0.01). Higher silage quality for all additives was obtained at filling one time than that filled three times (p<0.01). The highest DM and lowest DM loss rate (DMLR) occurred to MAX treatment at two filling methods (p<0.01); Digestibility of acid detergent fiber, neutral detergent fiber (NDF), and curde protein had the same results as silage quality (p<0.01). Yield of digestible DM and digestible NDF also showed higher value under MAX especially for filling one time (p<0.05). Conclusion: All corn silages showed good fermentation attributes (pH<4.0). The forage filled one time had higher silage quality than that filled three times (p<0.01). MAX with homofermentative lactic acid bacteria enhanced the lactic acid fermentation, silage quality and nutrient digestibility, and so improved the digestible nutrient yield.

Microbilolgical Studies on the Takju (Makguly) Brewing : The Korean Local Wine (한국 고유주의 일종인 막걸리에 대한 미생물학적 연구)

  • Koh, Choon-Myung;Choi, Tae-Joo;Lew, Joon
    • Korean Journal of Microbiology
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    • v.11 no.4
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    • pp.167-174
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    • 1973
  • This study included two parts of investigation, the microfloral changes during the brewing process with the changes of pH, total acidity, temperature and alcoholic contents, as well as determination of survival times of major enteric pathogens in Takju. 1. Maximum number of Saccharomyces cerevisiae was $4.3{\times}10^7$ per milliliter on the 5th day of fermentation and gradually decreased. Saccharomyces cerevisiae was one of the predominant strains of the fermentation process. The number of Saccharomyces cerevisiae was $4.3{\times}10^6$ per milliliter at the completion of the brewing and human consumption. In a few days after the completion of the brewing. Bacillus subtilis and some species of Staphylococcus spp. began to grow and those organisms were responsible for the spoilage. 2. Maximum pH, during the brewing, was 5.8 on the first day of fermentation and rapidly decreased until 6th day of fermentation at pH 4.3. 3. Maximum alcholic content was 14.5 degree on the 4th day of fermentation, 10.3 degree on the 5th day and this degree was continued during the experimentation. 4. Maximum temperature, during Takju brewing was 34.deg.C on the 3rd day of fermentation and rapidly decreased up to 23.deg.C on the 6th day and this temperature was continued until the brewing process was finished. 5. Maximum total acidity was 0.57 percent on the 4th day of fermentation and gradually decreased by brewing process was completed. 6. Survival time of major enteric pathogenic bacteria in Takju was as follows : Shigella dysenteriae and Escherichia coli were isolated in two hours and 14 hours respectively, but Salmonella typhi, Vibrio parahemolyticus were not isolated even in an hour after the inoculation of those organisms in undiluted Takju. In diluted Takju, Salmonella typhi, Vibrio parahemolyticus were not isolated even in an hour after the inoculation of those organisms in undiluted Takju. In diluted Takju, Salmonella typhi, Shigella dysenteriae, and Escherichia coli were survived for 50-60 hours, but Vibrio cholerae and Vibrio parahemolyticus were not isolated even if treated within one hour.

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A Study on Buchu(Leek, Aillium odorum) Kimchi-Changes in Chemical, Microbial and Sensory Properties, and Antimutagenicity of Buchu Kimchi during Fermentation

  • Lee, Kyeoung-Im;Jung, Keun-Ok;Rhee, Sook-Hee;Suh, Myung-Ja;Park, Kun-Young
    • Preventive Nutrition and Food Science
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    • v.1 no.1
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    • pp.23-29
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    • 1996
  • This study was conducted to investigate the changes in chemical, microbial and sensory characteristics, and antimutagenicity of buchu(leek, Allium odorum) kimchi during fermentation at 15$^{\circ}C$. Reducing sugar contents and pH of buchu kimchi were decreased during the fermentation. The reduction rate of reducing sugar of glutinous rice paste and shrimp added buvhu kimchi(GSBK) was faster than those of control buchu kimchi(CBK) and glutious rice paste added bucku kimchi(GBK). Acidity increased rapidly until 4 days,a nd optimum acidity (0.6%) of bucku kimchi was reached within 2 day. Also total bacterial and lactic acid bacterial counts greatly increased after 4 days of the fermentation. The numbers of lactic acid bacteria after 8 day- fermentation in CBK and GSBK, and 10 day-fermentation in GBK were the highest values, 4.5$\times${TEX}$10^{8}${/TEX} CFU/ml, 4.8$\times${TEX}$10^{8}${/TEX} CFU/ml and 6.1$\times${TEX}$10^{8}${/TEX} CFU/ml, respectively. In the sensory evaluation, appearance of sample was good at 0 day, taste from overall quality of buchu kimchi were asquired the highest values at 6th day. The methanol extracts from buchu kimchi(GBK) showed antimutagenicity against aflatoxin {TEX}$B_{1}${/TEX}({TEX}$AFB_{1}${/TEX})in Salmonella typhimurium TA100. The inhibition ration were 58~69% with treatment of the 5% methanol extracts, and when the adding concentration increased the effect increased.

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Effect on Fermentation and Storage of Yogurt Using Control System of Refrigerator (냉장고 제어시스템을 이용한 요구르트의 발효 및 저장효과)

  • Ko, Yong-Duck;Chung, Hee-Yeop;Kim, Kyeong-Sook;Lee, Kwang-Hoon;Kim, Yang-Woo;Chun, Sung-Sik;Sung, Nack-Kie
    • Korean Journal of Food Science and Technology
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    • v.26 no.6
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    • pp.814-818
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    • 1994
  • Control system for both rapid fermentation and storage of yogurt in refrigerator was developed and its performance was investigated. Fermentation temperature for normal and Bifidus containing yogurt was maintained at maximum $40^{\circ}C$ for about 7 and 11 hours, respectively. The pH, acidity, total viable cell number of lactic acid bacteria and viscosity of both yogurts after completing the fermentation were $4.23{\sim}4.29$, $0.93{\sim}0.97%$, $4.8{\times}10^7{\sim}$2.54{\times}10^8\;cfu/ml$ and $1,700{\sim}1,810\;cp$, respectively. The rate of fermentation for normal yogurt was faster than that of Bifidus yogurt. The changes of pH, acidity, viable cell number and viscosity during storage time were $4.09{\sim}4.54$, $0.76{\sim}1.1%$, $9.4{\times}10^6{\sim}5.68{\times}10^8\;cfu/ml$ and $1,450{\sim}2,000\;cp$, respectively. Yeast and fungi were not nearly detected during storage time for both yogurts.

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Changes of Characteristics in Kochujang Fermented with Maesil (Prunus mume) Powder or Concentrate (매실분말 및 농축액을 첨가한 고추장의 숙성중 품질 변화)

  • Park, Woo-Po;Cho, Sung-Hwan;Lee, Seung-Chul;Kim, Sung-Yong
    • Food Science and Preservation
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    • v.14 no.4
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    • pp.378-384
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    • 2007
  • Powder, or a concentrate, of maesil (Prunus mume) were used in the making of kochujang, and were added to kochujang at 0.5 or 1.0% (w/w). Kochujang fermented with maesil powder lower moisture content than did samples fermented with maesil concentrate. Moisture content slowly increased during fermentation, and was $3{\sim}4%$ higher than the initial value after 8 weeks of fermentation. Kochujang fermented with maesil powder or maesil concentrate showed lower pH values and higher total acidities than did the control. The total microbial count was $3.6{\times}10^7\;5.4{\times}10^7\;cfu/g$, and yeast and mold levels were $2.0{\times}10^7{\sim}3.6{\times}10^7\;cfu/g$, as kochujang fermentation commenced. Microbial load reached a maximum by 4 weeks of fermentation, and decreased thereafter. L (lightness), a (redness) and b (yellowness) values of kochujang gradually decreased during fermentation. Compared to methanol extracts of kochujang, water extracts and ethanol extracts showed higher free radical scavenging abilities at the initial stage of fermentation. Control, and samples with 0.5% (w/w) maesil powder or maesil concentrate, attained higher scores in sensory evaluation tests than did samples with higher maesil levels, and were not significantly different at P>0.05 as determined by Duncan's multiple range test.

Qualify Characteristics of Baechukimchi Added Ginseng during Fermentation Periods (인삼이 첨가된 배추김치의 발효중 품질 특성)

  • Ku, Kyung-Hyung;Lee, Kyung-A;Park, Wan-Soo
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.10
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    • pp.1444-1448
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    • 2006
  • This study was investigated for quality characteristics of Baechukimchi with ginseng during fermentation. For Baechukimchi preparation, original ingredients of Baechukimchi and high contents of ginseng were used. In the initial pH and titratable acidity of each samples, ginseng -added Kimchi showed a little higher value than pH 5.48 and 0.25% acidity of the control Kimchi. Ginseng-added Kimchi showed higher values of total microbes $(1.90\times10^6\sim2.93\times10^6)$ and lactic acid bacteria $(2.21\times10^6\sim2.62\times10^6)$ than the control Kimchi. The control Kimchi was total microbes of $1.59\times10^5$ and lactic acid bacteria of $7.60\times10^4$. According to fermentation periods, ginseng-added Kimchi showed decrease of pH and increase of titratable acidity than the control Kimchi, but it. was not different for the microbes between Kimchi samples. In the taste intensity of sensory evaluation, ginseng-added Kimchi was evaluated higher value than the control Kimchi and kept up texture, properties of initial preparation between samples during fermentation periods. In the crude saponin content, raw ginseng was 5.89% by dry basis and it was decreased to 3.74% after fermentation. And the individual ginsenosides content of Re, $Rg_1$, Rf, $Rg_2,\;Rh_1,\;Rb_1,$, Rc, $Rb_2$, Rd, $Rg_3$, but $Rg_3$ were decreased and $Rh_1$ were increased from 16.6 mg%, and 22.2 mg/% to 59.2 mg%, and 39.4 mg%, respectively.

Kinetic Studies on Submerged Acetic Acid Fermentation of Acetobacter aceti (Acetobacter aceti균의 심부배양에 의한 초산발효의 동력학적 연구)

  • KIM Sang-Moo;LEE Keun-Tai
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.25 no.4
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    • pp.301-306
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    • 1992
  • In order to determine the optimal conditions for the process of acetic acid fermentation, the kinetics of Acetobacter aceti fermentation in submerged batch cultures were studied at different agitation speeds and air flow rates. The maximum cell concentration was noted after about 48 hr fermentation and the time course of Acetobactey aceti fermentation showed a distinct feature of growth-associated product formation. At agitation speeds 700, 500, and 300 rpm fixed on air flow rate 1 v/v/M, specific grow rates were $3.97\times10^{-2},\;3.82\times10^{-2},\;and\;2.04\times10^{-2\} \;hr^{-1}$, saturation constants were 61.4, 64.6, and 69.4mg/ml. and volumetric oxygen transfer coefficients were 0.9337, 0.4468, and 0.1701 $min^{-1},$ respectively. At air flow rates 1.25, 1.00, and 0.75 v/v/M fixed on agitation speed 500 rpm, specific growth rates were $3.90\times10^{-2},\;3.82\times10^{-2},\;and\;2.37\times10^{-2}\;hr^{-1}$, saturation constants were 63.4, 64.6, and 64.9 mg/ml, and volumetric oxygen transfer coefficient were 0.4923, 0.4468, and 0.3509 $min^{-1},$ respectively.

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