• Title/Summary/Keyword: bacteria counts

Search Result 918, Processing Time 0.032 seconds

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
    • /
    • v.1 no.1
    • /
    • pp.23-29
    • /
    • 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.

  • PDF

Partial replacement of pork backfat with konjac gel in Northeastern Thai fermented sausage (Sai Krok E-san) to produce the healthier product

  • Sorapukdee, Supaluk;Jansa, Sujitta;Tangwatcharin, Pussadee
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.32 no.11
    • /
    • pp.1763-1775
    • /
    • 2019
  • Objective: The influence of konjac gel level on fermentation process and product qualities were assessed to evaluate the feasibility of using it as fat analog in Northeastern Thai fermented sausage (Sai Krok E-san). Methods: Five treatments of fermented sausages were formulated by replacing pork backfat with 0%, 7.5%, 22.5%, and 30% konjac gel. The changes in lactic acid bacteria (LAB) and important physicochemical properties of samples were assessed during 3 days of fermentation. After the end of fermentation at day 3, water activity ($a_w$), instrumental texture, color, microbial counts, and sensory evaluation were compared. The best product formulation using konjac for replacing pork back fat were selected and used to compare proximate composition and energy value with control sample (30% pork backfat). Results: An increase in konjac gel resulted in higher values of LAB, total acidity, and proteolysis index with lower pH and lipid oxidation during 3 days of product fermentation (p<0.05). It was noted that larger weight loss and product shrinkage during fermentation was observed with higher levels of konjac gel (p<0.05). The resulting sausage at day 3 with 15% to 30% konjac gel exhibited higher hardness, cohesiveness, gumminess, springiness, and chewiness than control (p<0.05). The external color of samples with 22.5% to 30% konjac gel were redder than others (p<0.05). Mold, Salmonella spp., Staphylococcus aureus, and Escherichia coli in all finished products were lower than detectable levels. Product with 15% konjac gel had the highest scores of sourness linking and overall acceptability (p<0.05). Conclusion: The product with 15% of konjac gel was the optimum formulation for replacing pork backfat. It had higher sensorial scores of sourness and overall acceptability than control with less negative impact on external appearance (product shrinkage) and weight loss. Moreover, it provided 46% fat reduction and 32% energy reduction than control.

Improvements in Storage Stability of Undaria pinnatifida after Gamma Irradiation (감마선 조사에 의한 미역의 저장성 개선)

  • Kim, Hyun-Joo;Choi, Jong-Il;Kim, Jae-Hun;Chun, Byung-Soo;Ahn, Dong-Hyun;Kim, Gwang-Hoon;Byun, Myung-Woo;Lee, Ju-Woon
    • Food Science and Preservation
    • /
    • v.16 no.4
    • /
    • pp.590-593
    • /
    • 2009
  • The effect of gamma irradiation on the storage stability of Undaria pinnatifida was investigated. A three-log reduction in total aerobic bacteria in U. pinnatifida samples was obtained by irradiation with 3 kGy. During storage for 2 weeks, the viable counts of microorganisms in non-irradiated U. pinnatifida increased to 6 log CFU/g. However, irradiation of U. pinnatifida by 5 kGy eliminated microorganisms. The Hunter $L^{\ast}-value$ of U. pinnatifida was slightly increased after 5 kGy of irradiation. The hardness properties of U. pinnatifida decreased during storage, but were not changed by irradiation with up to 3 kGy. These results indicate that low-dose irradiation (3 kGy) could be effective for improvement of the storage stability of U. pinnatifida.

Evaluation on Microbial Contamination in Chinese Cabbage Cultivated Soil in Korea

  • Jung, Kyu-Seok;Seo, Seung-Mi;Jeon, Hye-Jin;Kim, So-Ra;Kim, Won-Il;Kim, Se-Ri;Roh, Eun-Jung;Ryu, Jae-Gee;Lee, Seung-Don
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.50 no.6
    • /
    • pp.538-546
    • /
    • 2017
  • The occurrence of various pathogenic microorganisms on farms is a concern if they are able to contaminate fresh produce, which provides entry into the food supply. This study was undertaken to assess the microbiological quality and prevalence of pathogens in Chinese cabbage cultivated soil in Korea. A total of 57 Chinese cabbage cultivated soils were collected in 4 locations in Korea from February to August 2017. The soils were analyzed for the presence of total aerobic bacteria, Escherichia coli, coliforms, Salmonella spp., Escherichia coli O157:H7, Listeria monocytogenes, and Staphylococcus aureus. The total aerobic plate counts in soils were in the range of 5.7 to $8.7log\;CFU\;g^{-1}$. The coliforms and E. coli were detected in 39 and 8 out of 57 soil samples, respectively, in the range of 1.1 to $6.3log\;CFU\;g^{-1}$ and 0.7 to $4.0log\;CFU\;g^{-1}$. Salmonella spp., E. coli O157:H7, L. monocytogenes, and S. aureus were not detected from any samples. Results from these studies may help control the spread of bacterial species such as E. coli and Salmonella spp. through the farm environment.

Antimicrobial activity of fermented Maillard reaction products, novel milk-derived material, made by whey protein and Lactobacillus rhamnosus and Lactobacillus gasseri on Clostridium perfringens

  • Kim, Yujin;Kim, Sejeong;Lee, Soomin;Ha, Jimyeong;Lee, Jeeyeon;Choi, Yukyung;Oh, Hyemin;Lee, Yewon;Oh, Nam-su;Yoon, Yohan;Lee, Heeyoung
    • Animal Bioscience
    • /
    • v.34 no.9
    • /
    • pp.1525-1531
    • /
    • 2021
  • Objective: The objective of this study was to evaluate the antimicrobial effects of fermented Maillard reaction products made by milk proteins (FMRPs) on Clostridium perfringens (C. perfringens), and to elucidate antimicrobial modes of FMRPs on the bacteria, using physiological and morphological analyses. Methods: Antimicrobial effects of FMRPs (whey protein plus galactose fermented by Lactobacillus rhamnosus [L. rhamnosus] 4B15 [Gal-4B15] or Lactobacillus gasseri 4M13 [Gal-4M13], and whey protein plus glucose fermented by L. rhamnosus 4B15 [Glc-4B15] or L. gasseri 4M13 [Glc-4M13]) on C. perfringens were tested by examining growth responses of the pathogen. Iron chelation activity analysis, propidium iodide uptake assay, and morphological analysis with field emission scanning electron microscope (FE-SEM) were conducted to elucidate the modes of antimicrobial activities of FMRPs. Results: When C. perfringens were exposed to the FMRPs, C. perfringens cell counts were decreased (p<0.05) by the all tested FMRPs; iron chelation activities by FMRPs, except for Glc-4M13. Propidium iodide uptake assay indicate that bacterial cellular damage increased in all FMRPs-treated C. perfringens, and it was observed by FE-SEM. Conclusion: These results indicate that the FMRPs can destroy C. perfringens by iron chelation and cell membrane damage. Thus, it could be used in dairy products, and controlling intestinal C. perfringens.

Fermentation of red ginseng extract by the probiotic Lactobacillus plantarum KCCM 11613P: ginsenoside conversion and antioxidant effects

  • Jung, Jieun;Jang, Hye Ji;Eom, Su Jin;Choi, Nam Soon;Lee, Na-Kyoung;Paik, Hyun-Dong
    • Journal of Ginseng Research
    • /
    • v.43 no.1
    • /
    • pp.20-26
    • /
    • 2019
  • Background: Ginsenosides, which are bioactive components in ginseng, can be converted to smaller compounds for improvement of their pharmacological activities. The conversion methods include heating; acid, alkali, and enzymatic treatment; and microbial conversion. The aim of this study was to determine the bioconversion of ginsenosides in fermented red ginseng extract (FRGE). Methods: Red ginseng extract (RGE) was fermented using Lactobacillus plantarum KCCM 11613P. This study investigated the ginsenosides and their antioxidant capacity in FRGE using diverse methods. Results: Properties of RGE were changed upon fermentation. Fermentation reduced the pH value, but increased the titratable acidity and viable cell counts of lactic acid bacteria. L. plantarum KCCM 11613P converted ginsenosides $Rb_2$ and $Rb_3$ to ginsenoside Rd in RGE. Fermentation also enhanced the antioxidant effects of RGE. FRGE reduced 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and reducing power; however, it improved the inhibition of ${\beta}$-carotene and linoleic acid oxidation and the lipid peroxidation. This suggested that the fermentation of RGE is effective for producing ginsenoside Rd as precursor of ginsenoside compound K and inhibition of lipid oxidation. Conclusion: This study showed that RGE fermented by L. plantarum KCCM 11613P may contribute to the development of functional food materials.

Quality and Antioxidant Effects of the Korean Traditional Rice Wine Makgeolli Supplemented with Codium fragile during Fermentation (청각(Codium fragile)을 첨가하여 제조한 막걸리의 발효 중 품질특성 및 항산화 효과)

  • Jun, Eun Bi;Choi, Man-Seok;Park, Shin Young
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.52 no.3
    • /
    • pp.224-231
    • /
    • 2019
  • This study investigated the physicochemical, microbiological, antioxidant, and sensory characteristics of Makgeolli supplemented with 10, 20, and 30% Codium fragile (Cf) during an 8-day fermentation period. The pH and acidity on day 0 were lower in Makgeolli supplemented with Cf (pH 3.55-3.65, acidity 0.26-0.29%) than in the unsupplemented Makgeolli (control) (pH 3.72, acidity 0.23%). The pH and acidity of Cf Makgeolli on day 8 were 3.08-3.12 and 0.67-0.75%, respectively. The sugar content increased steadily until day 4 (8.1-8.5 Brix) and then decreased steadily (6.5-6.8 Brix). The alcohol content increased steadily until day 8 (13.2-14.3%). The pH decreased, acidity increased, and alcohol content increased significantly (all P<0.05), with stepwise increases in fermentation time and Cf concentrations. The lactic acid bacteria counts were 9.28-9.37 log versus 8.18 log in the control. The DPPH (1,1-diphenyl-2-picrylhydrazyl) and ABTS [2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)] radical scavenging activities were higher in Cf Makgeolli (DPPH 74.63-84.64%, ABTS 51.01-64.79%) than in the control (DPPH 30.97%, ABTS 21.21%). Makgeolli supplemented with 10 and 20% Cf had the highest taste, smell, and overall acceptance scores. This study suggests that Makgeolli supplemented with 10 and 20% Cf could be developed due to its good physicochemical and microbiological characteristics, including high antioxidant properties and good consumer acceptance.

Shelf-Life Extension and Increase in Survivability of Probiotics Powder by Ultrasonic Treatment (초음파를 이용한 프로바이오틱스 분말의 유통기한 연장 및 생존율 증대 효과)

  • Hong, Dong-Ki;Jung, Seong-Eun;Lee, Myoung-Hee;Lee, Ho-Jin;Lee, Jae-Ho;Na, Guk-Nam;Choi, Il-Dong;Lee, Jung-Lyoul;Sim, Jae-Hun
    • Journal of Dairy Science and Biotechnology
    • /
    • v.36 no.4
    • /
    • pp.220-225
    • /
    • 2018
  • The purpose of this study was to investigate the effect of ultrasonic treatment during probiotics production process on the shelf life and the survival rate. Once Lactobacillus plantarum and Bifidobacterium longum were cultured in edible culture medium, ultrasonic treatment was performed at 100 Hz for 1, 2, 5, 7, and 10 minutes. Ultrasonic-treated L. plantarum HY7715 and B. longum HY8001 were centrifuged, mixed with a cryoprotectant, and lyophilized. The prepared lactic acid bacteria powder was individually packaged. After 6 months, viable cell counts were measured separately under cold storage and room temperature. In vitro digestion experiments were performed to determine the survival rate at digestive tract. As a result, it was observed that shelf life and survival rate were increased compared to untreated control group.

Selection of indigenous starter culture for safety and its effect on reduction of biogenic amine content in Moo som

  • Tangwatcharin, Pussadee;Nithisantawakhup, Jiraroj;Sorapukdee, Supaluk
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.32 no.10
    • /
    • pp.1580-1590
    • /
    • 2019
  • Objective: The aims of this study were to select one strain of Lactobacillus plantarum (L. plantarum) for a potential indigenous safe starter culture with low level antibiotic resistant and low biogenic amine production and evaluate its effect on biogenic amines reduction in Moo som. Methods: Three strains of indigenous L. plantarum starter culture (KL101, KL102, and KL103) were selected based on their safety including antibiotic resistance and decarboxylase activity, and fermentation property as compared with a commercial starter culture (L. plantarum TISIR543). Subsequently, the effect of the selected indigenous safe starter culture on biogenic amines formation during Moo som fermentation was studied. Results: KL102 and TISIR 543 were susceptible to penicillin G, tetracycline, chloramphenicol, erythromycin, gentamycin, streptomycin, vancomycin, ciprofloxacin and trimethoprim (MIC90 ranging from 0.25 to $4{\mu}g/mL$). All strains were negative amino acid-decarboxylase for lysis of biogenic amines in screening medium. For fermentation in Moo som broth, a relatively high maximum growth rate of KL102 and TISIR543 resulted in a generation time than in the other strains (p<0.05). These strain counts were constant during the end of fermentation. Similarly, KL102 or TISIR543 addition supported increases of lactic acid bacterial count and total acidity in Moo som fermentation. For biogenic amine reduction, tyramine, putrescine, histamine and spermine contents in Moo som decreased significantly by the addition KL102 during 1 d of fermentation (p<0.05). In final product, histamine, spermine and tryptamine contents in Moo som inoculated with KL102 were lower amount those with TISIR543 (p<0.05). Conclusion: KL102 was a suitable starter culture to reduce the biogenic amine formation in Moo som.

Characteristics of fermented milk containing Bifidobacterium growth promoter (BE0623) and dietary fiber

  • Cho, Young Hoon;Sim, Jae Young;Nam, Myoung Soo
    • Korean Journal of Agricultural Science
    • /
    • v.48 no.2
    • /
    • pp.209-218
    • /
    • 2021
  • This study was carried out to investigate the effects of Bifidobacteria growth promoter BE0623 and a dietary fiber supplement, which included Bifidobacterium lactis BB12, Lactobacillus acidophilus, Streptococcus thermophilus, and Bifidobacterium lactis. In fermented milk containing BE0623, the viable cell count of Bifidobacteria significantly increased by about 45 to 75 times compared to the control, and the titratable acidity increased, whereas the pH decreased. All fractions obtained by isolating BE0623 had Bifidobacteria growth effect. Acacia dietary fiber is a pale yellow powder. It has a viscosity of 60 to 100 cPs and a pH between 4.1 and 5.0. Its general components are less than 10% moisture, more than 90% dietary fiber, and less than 4% ash. The optimal addition ratio of Bifidobacteria growth promoting material was determined to be 0.05%. The general components of the manufactured fermented milk were carbohydrate 17.85%, protein 3.63%, fat 3.00%, and dietary fiber 2.95%. During storage of the fermented milk for 24 days, its titratable acidity, viscosity, and sugar content all met the criteria. In addition, the viable cell counts of Bifidobacteria and lactic acid bacteria in the fermented milk were 1.7 × 108 CFU·mL-1 and 1.5 × 107 CFU·mL-1, respectively, and Escherichia coli was negative. There was no significant difference between the control group and the treatment group in the sensory evaluation of sweet, sour, weight, and flavor, and the preference for the treatment group was excellent. The acceptability of the fermented milk of the treated group according to the storage period was excellent in terms of color, flavor, and appearance.