• 제목/요약/키워드: total viable cell

검색결과 295건 처리시간 0.021초

김치찌개용 양념의 저장 및 품질특성의 변화 (Changes in Physicochemical Properties and Microorganisms during the Storage of Kimchi Stew저s Sauce)

  • 권혜순
    • 한국식품영양과학회지
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    • 제28권1호
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    • pp.107-112
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    • 1999
  • Physicochemical properties and microflora of kimchi stew's sauce were investigated during 6 months at 13oC, 27oC and 37oC to study the changes of its quality. The final pH values in the sauce showed a slight decrease to 4.46, 4.38 and 4.21 during storage at 13oC, 27oC and 37oC, respectively. Color(L, a, b values), salinity, moisture and Aw in the sauce were decreased during storage. However, the values of brix and browning, and the amounts of total sugar, crude protein and crude fat in the sauce were increased during storage. All the reactions occurred more rapidly in the samples stored at 37oC than those stored at 27oC and 13oC. The viable cell counts of aerobic bacteria in the sauce were changed remarkably during storage, but viable cell counts of lactic acid bacteria were decreased. Yeast, mold and E. coli were not found in the above temperatures during storage. Regression analysis between sensory scores and quality characteristics showed that the ΔE value was a major quality index for the deterioration of kimchi stew's sauce. The shelf lives of sauces at 13oC, 27oC, 37oC were estimated to be 24 months, 6 months and 6 months, respectively.

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Edwardsiella tarda의 비배양성 생존상태(VBNC) 유도 및 소생 특성 (Induction and resuscitation of viable but nonculturable Edwardsiella tarda)

  • 강남이;김은희
    • 미생물학회지
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    • 제52권3호
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    • pp.313-318
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    • 2016
  • Viable but nonculturable (VBNC) 상태에 들어간 세균은 일반적인 증균 배지에서는 집락을 형성하지 않지만, 죽은 것이 아니라 낮은 대사활성상태로 유지되고 있다. 본 연구에서는 $10^{\circ}C$의 저온 빈영양 해수에서 Edwardsiella tarda를 VBNC 상태로 유도한 후, 해수 온도를 10에서 $25^{\circ}C$로 상승시킬 때 첨가된 유기물의 종류에 따라 VBNC 상태인 균의 소생 가능성을 알아보고자 하였다. E. tarda가 접종된 빈영양 해수 microcosm을 $10^{\circ}C$에 유지하였을 때 VBNC 유도 기간은 42-84일까지 다양하였다. 유도 기간 동안 acridine orange direct counting법으로 계수한 총 균수는 초기 접종 농도인 약 $10^8cells/ml$로 일정하였으며, direct viable counting법으로 계수한 생존 균수는 약 $10^4cells/ml$로 감소되었다. VBNC E. tarda에 효모추출물, 넙치근육추출물 그리고 혈청을 첨가하여 $25^{\circ}C$에서 소생을 유도한 결과 전체 시료 개수의 37%, 23%, 37%에서 각각 소생이 확인되었으며 소생된 E. tarda의 특성은 VBNC 유도 전 원래의 세균과 일치하였다. 소생된 E. tarda를 넙치(Paralichthys olivaceus)에 복강 주사 하였을 때 접종 후 5일 이내에 시험어가 모두 사망함으로써 VBNC 상태의 E. tarda가 독력을 유지하고 있었음을 시사하였다. 그러므로 E. tarda는 우리나라 남해 연안 겨울의 저온 빈영양 해수에서 VBNC 상태로 유도되었다가 여름과 가을 시기에 수온 상승과 더불어 소생되어 양식 넙치에 지속적인 발병 요인이 되고 있는 것으로 생각된다.

부추첨가 김치의 발효특성 변화 (Changes in Fermentation Characteristics of Kimchi Added with Leek)

  • 이귀주;김유경
    • 한국식품영양과학회지
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    • 제28권4호
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    • pp.780-785
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    • 1999
  • The effect of addition in different amounts of leek(4, 8, 12% respectively) during fermentation of kimchi was investigated. Fermentation characteristics such as pH, acidity and total reducing sugars as well as microbiological properties were determined. During fermentation, pH was more slowly lowered in kimchi added with leek than in control and titrable acidity of these kimchi was lower than that of control. Viable cells of total bacteria and lactic acid bacteria in these kimchi were higher than that of control during fermentation. Content of total reducing sugars was higher than that of control. Three kinds of reducing sugars such as fructose, glucose and galactose were detected and the dominant one appeared to be fructose. These results suggested that addition of leek seems to retard fermentation of kimchi due to their anti microbial actvity.

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인삼식초에 관한연구 (Studies on Ginseng Vinegar)

  • 김승겸
    • 한국식품영양학회지
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    • 제12권5호
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    • pp.447-454
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    • 1999
  • Ginseng-vinegars were produced by the fermentation of 5% ethanol solution contained ginseng, red ginseng, ginseng marc and red ginseng marc using Acetobacter aceti 3281 for 26 days at 35$^{\circ}C$. The ginseng and red ginseng vinegar contained 0.236mg/ml of total sugar 0.236mg/ml of reducing sugar and 0.05% of ethanol and 1.005 of specific gravity 8,58CFU of viable cell count 3,24 of pH and 5.11% of acidity. Whereas the vinegars produced using the water-extracted red ginseng marc and the ethanol-extracted red ginseng marc were consisted of total sugar was 1.27mg/ml and 1.60mg/ml reducing sugar was 0.077mg/ml and 0.725mg/ml specific gravity was 1.001 and 1.004 the number of viable cells was 8.51CFU/ml and 8.1CFU/ml pH was 2.81 and 2.89 acidity was 5.18% and 5.32% respectvely ethanol concentration was 0.05% in both cases. In five-grade scoring test of sensory evaluation, it was estimated favorable that each vinegar made by were-extracted red ginseng marc, ethanol-extracted red ginseng marc ginseng and red ginseng ginseng from 0.5 to 32% of water-and ethanol-extract red ginseng was extracted with 10% white vinegar for 30 days. The best sensory vinegars were obtained that ginseng of 0.4~1.6% above red glnsend of 0.8% water-extracted red ginseng marc of 0.8~1.6% and ethanol-extracted red ginseng marc of 0.4~1.6% added in 10% white vinegar respectively.

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이란 발효 유제품에서 분리한 유산균의 특성 (Characterization and Identification of Lactic Acid Bacteria Isolated from Fermented Milks in Iran)

  • 박효주;박동준;오세종
    • Journal of Dairy Science and Biotechnology
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    • 제41권4호
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    • pp.211-218
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    • 2023
  • This study aimed to identify lactic acid bacteria isolated from eight fermented milk products in Iran. We enumerated Lactobacillus species using De Man-Rogosa-Sharpe (MRS)-maltose and MRS agar with pH adjusted to 5.2, as well as assessment at 37℃ for 48 hr, studied Streptococcus spp. using M17 agar at 43℃ for 24 hr, and assessed Bifidobacterium species using nalidixic acid, paromomycin sulfate, neomycin sulfate, and lithium chloride (BL-NPNL) agar at 37℃ for 48 hr. The total viable Streptococcus spp. cell in fermented milk varied at 4.73-8.83 log CFU/mL. However, Bifidobacterium spp. were not detected in any of the tested samples. Lactobacilli were not detected in four of the eight samples, and viable Lactobacilli cells in the remaining four samples ranged 2.48-3.85 log CFU/mL. The pH of the tested samples ranged 3.53-4.19, and soluble solids (Brix measurement) ranged 7.5%-17.9%. A total of 130 isolates of gram-positive catalase-positive bacteria were characterized at the species level using 16S rRNA sequencing. Sequence analysis identified six species: Streptococcus thermophilus, Lactobacillus delbrueckii subsp. sunkii, Lactobacillus delbrueckii subsp. indicus, Lactiplantibacillus plantarum, Lacticaseibacillus rhamnosus, and Levilactobacillus brevis.

Effects of Knockout Serum Replacement in the Culture Medium on the Proliferation of Porcine Fetal Fibroblasts In Vitro

  • Kim, Eun-Ju;Park, Jung-Joo;Choi, Young-Ju;Park, Sang Kyu;Roh, Sang-Ho
    • International Journal of Oral Biology
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    • 제35권1호
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    • pp.1-5
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    • 2010
  • Human fibroblasts that maintain the structural integrity of connective tissues by secreting precursors of the extracellular matrix are typically cultured with serum. However, there are potential disadvantages of the use of serum including unnatural interactions between the cells and the potential for exposure to animal pathogens. To prevent the possible influence of serum on fibroblast cultures, we devised a serum-free growth method and present in vitro data that demonstrate its suitability for growing porcine fetal fibroblasts. These cells were grown under four different culture conditions: no serum (negative control), 10% fetal bovine serum (FBS, positive control), 10% knockout serum replacement (KSR) and 20% KSR in the medium. The proliferation rates and viabilities of the cells were investigated by counting the number of cells and trypan blue staining, respectively. The 10% FBS group showed the largest increase in the total number of cells ($1.09\;{\times}\;10^5\;cells/ml$). In terms of the rate of viable cells, the results from the KSR supplementation groups (20% KSR:64.7%; 10% KSR: 80.6%) were similar to those from the 10% FBS group (68.5%). Moreover, supplementation with either 10% ($3.0\;{\times}\;10^4\;cells/ml$) or 20% KSR ($4.8\;{\times}\;10^4\;cells/ml$) produced similar cell growth rates. In conclusion, although KSR supplementation produces a lower cell proliferation rate than FBS, this growth condition is more effective for obtaining an appropriate number of viable porcine fetal fibroblasts in culture. Using KSR in fibroblast culture medium is thus a viable alternative to FBS.

저선량 방사선 처리가 탁주 품질특성에 미치는 영향 (Effect of Low-Dose Radiation on Quality Characteristics of Takju)

  • 이윤규;탁은미;김보미나;서충원;최승환;신용섭;김선칠
    • 대한디지털의료영상학회논문지
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    • 제13권3호
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    • pp.133-137
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    • 2011
  • This research investigated how low dose radiation affected the quality characteristics of Takju. The treatment group were the quality characteristics of control group, Takju treated by radiation of separate 4, 7, 10 Gy and sterilized Takju. We measured pH, titratable acidity, alcohol, brix, total viable cell count, Hunter's color values, sensory characteristic. As a result, We discovered there were minute changes in pH, titratable acidity, alcohol, brix, total viable cell count. Likewise, The color appeared changes on separate radiation dose. In the sensory characteristic, People's preference ranked better than average level according to priority Takju treated by 4, 7, 10 radiation. In conclusion, Low dose radiation had little effect on the quality characteristics of Takju. However, Takju received a favorable review by some people In test of taste such as after taste. So We thought, such as preservation, the research using the radiation should be continually conducted.

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Microbial Contamination by Bacillus cereus, Clostridium perfringens, and Enterobacter sakazakii in Sunsik

  • Lee, Eun-Jin;Kim, Sung-Gi;Yoo, Sang-Ryeol;Oh, Sang-Suk;Hwan, In-Gyun;Kwon, Gi-Sung;Park, Jong-Hyun
    • Food Science and Biotechnology
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    • 제16권6호
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    • pp.948-953
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    • 2007
  • The powdered cereal sunsik is a partially thermal-processed product that required safety evaluations for food-borne pathogens. Thirty-six sunsik products from Korean markets were collected and analyzed for contamination by total viable cell counts, coliforms, Escherichia coli, and the spore-forming Clostridium perfringens and Bacillus cereus. Enterobacter sakazakii, as a newly emerging pathogen, was also analyzed. Approximately 28% of sunsik were contaminated at 5 log CFU/g for total viable counts. Coliforms and E. coli were detected in 33 and 4% of the samples, respectively. The spore-forming B. cereus was found in 42% of the samples at a maximal level of 3 log CFU/g on average. About 6% the samples were contaminated with Cl. perfringens at an average level of 15 CFU/g. Forty-five % of sunsik contained E. sakazakii, at levels from 0.007 to over 1.1 cell/g by MPN method. In addition, one sunsik product for infants and children showed over 3 log CFU/g for both B. cereus and E. sakazaki. Therefore, concern should be placed on controlling for microbial hazards such as B. cereus and E. sakazakii in sunsik, particularly for the products fed to infants under 6 months of age.

두부의 저장성에 미치는 복분자, 가자육, 오배자 에탄올 추출물의 효과 (Effects on the Shelf-life of Tofu with Ethanol Extracts of Rubus coreanus miquel, Therminalia chebula Retz and Rhus javanica)

  • 오세욱;이영철;홍희도
    • 한국식품과학회지
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    • 제34권4호
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    • pp.746-749
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    • 2002
  • 정향피, 초두구, 복분자, 산사자, 가자육, 금앵자, 오배자의 7종에 대한 에탄올 추출물을 제조하여 10종의 공시균주에 대하여 paper disk method에 의한 항균활성을 측정하였다. 복분자, 가자육, 오배자 3종이 선발되었으며 이의 에탄올 추출물을 두부에 0.01%, 0.05 및 0.1%(w/w)의 농도로 첨가하여 $5^{\circ}C$에서 저장하면서 총균수를 측정한 결과, 저장 4일 정도에 부패에 도달하는 것으로 판단되었다. 총균수 그래프의 회귀방정식을 구하여 유통가능 기간을 산출하였을 때 가자육 추출물을 첨가한 처리구의 경우 0.01% 첨가 처리구가 대조구에 비하여 저장기간이 108.8% 연장된 것으로 측정되었으며, 0.05% 첨가 처리구는 117.3%, 0.1% 첨가 처리구는 132.6% 연장되는 효과가 있는 것으로 판단되었다. 3종의 추출물 중 가자육 추출물이 가장 저장성을 연장시키는 효과가 우수한 것으로 나타났으며 복분자, 오배자 추출물은 가자육 추출물에 비하여 그 효과가 다소 미약한 것으로 판단되었다.

매실(Prunes mime) 착즙액이 Yoghurt Starter의 산생성 및 증식에 미치는 영향 (The Effect of Maesil(Prunus mime) Extract on the Acid Production and Growth of Yoghurt Starter)

  • 박신인;이은희;남은숙
    • 한국식품영양학회지
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    • 제15권1호
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    • pp.42-50
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    • 2002
  • Skim milk에 매실 착즙액을 수준별로 첨가하고 4종(Streptococcus thermophilus, Lactobacillus acidophilus, Lactobacillus bulgaricus, Lactobacillus casei)의 젖산균을 단독균주 또는 혼합균주로 접종하여 매실 착즙액의 첨가가 젖산균의 산생성 및 생육에 미치는 영향과 저장성을 조사하였고, 매실 착즙액으로 사용한 매실의 일반 성분을 분석하였다. 매실의 일반 성분은 조회분 0.4%, 식이섬유 4.1%, 구연산 4.66%, 총당 0.264%, vitamin C 405.34mg%이었고, 매실 착즙액의 첨가는 젖산균의 증식을 촉진시켰으며 산생성도 증가하였다. 실험구 중 Str. thermophilus, Lac. acidophilus와 Lac. casei의 혼합균주에 3% 매실 착즙액을 첨가한 실험구가 가장 많은 양의 젖산(1023%)을 생성하였고, 가장 높은 생성균수(3.6$\times$$10^{11}$ cfu/mL)를 나타내었다. 매실 착즙액 3% 첨가 호상 요구르트를 대조구와 함께 4$^{\circ}C$와 2$0^{\circ}C$에서 30일 동안 저장한 결과, 세 개의 혼합균주(Str. thermophilus, Lac. acidophilus)를 사용한 호상 요구르트가 4$^{\circ}C$에서 pH는 4.25, 생균수는 4.1$\times$$10^{9}$ cfu/mL 이었고, 2$0^{\circ}C$에서 pH는 3.76, 생균수는 8.7$\times$$10^{8}$ cfu/mL으로 대조구인 매실 무첨가 호상 요구르트에 비하여 높은 저장성을 나타내었다. 이상의 결과로 보아 매실 착즙액을 첨가한 호상 요구르트의 제조가 가능할 것으로 사료된다.