Microbial Safety and Quality Evaluation of UV-Treated, Cold-Pressed Colored and Turbid Juices and Beverages

2018 ◽  
Vol 81 (9) ◽  
pp. 1549-1556 ◽  
Author(s):  
JESSIE USAGA ◽  
RANDY W. WOROBO
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Uv Light ◽  
Processing Unit ◽  
Fruit And Vegetable ◽  
Processing Technologies ◽  
Constant Flow Rate ◽  
Log Reduction ◽  
Nonthermal Processing ◽  
Cold Pressed

ABSTRACT The growing demand for fruit and vegetable juice blends, with improved nutritional and sensory attributes, has prompted the industrial adoption of nonthermal processing technologies, including UV light. Limited studies have explored conditions to overcome the well-known limitations of UV when treating liquid foods with a high content of particles that absorb or scatter UV light. This study addressed the effectiveness of the application of UV light, using a commercial processing unit, to inactivate pathogenic Escherichia coli O157:H7, Salmonella enterica (hereafter Salmonella), and Listeria monocytogenes, as well as spoilage microorganisms, in colored and turbid juices and beverages. The inactivation of cocktails of five strains (or serotypes) of E. coli O157:H7, Salmonella, and L. monocytogenes isolated from fruit- and vegetable-derived products linked to outbreaks was determined in seven colored and turbid cold-pressed juices and beverages. Juices and beverages were UV treated at a constant flow rate of 150 L/h through multiple consecutive passes. The inactivation of aerobic mesophilic bacteria, molds and yeasts, and lactic acid bacteria was also assessed at the cumulative dose that guaranteed a 5-log reduction of the most UV-tolerant pathogen for each product. A 5-log reduction of the three pathogens was achieved in all juices and beverages at a maximum cumulative UV dose of 12.0 ± 0.6 mJ/cm2. The dose required to ensure the targeted reduction varied depending on the tested product and the inoculated pathogen. The reduction of aerobic mesophiles, molds and yeasts, and lactic acid bacteria varied from 0.5 to 3.6, from 0.2 to 2.0, and from 0.5 to 3.6 log CFU/mL, respectively. Thus, the proposed treatment represents a suitable processing alternative to ensure the safety and extend the shelf life of colored and turbid cold-pressed juices and beverages.

Use of UV Light for the Inactivation of Listeria monocytogenes and Lactic Acid Bacteria Species in Recirculated Chill Brines

2008 ◽  
Vol 71 (3) ◽  
pp. 629-633 ◽  
Author(s):  
K. M. GAILUNAS ◽  
K. E. MATAK ◽  
R. R. BOYER ◽  
C. Z. ALVARADO ◽  
R. C. WILLIAMS ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Listeria Monocytogenes ◽  
Lactic Acid Bacteria ◽  
Thermal Processing ◽  
Uv Light ◽  
Light Exposure ◽  
Meat Products ◽  
Uv Treatment ◽  
Bacterial Populations ◽  
Log Reduction

Ready-to-eat meat products have been implicated in several foodborne listeriosis outbreaks. Microbial contamination of these products can occur after thermal processing when products are chilled in salt brines. The objective of this study was to evaluate UV radiation on the inactivation of Listeria monocytogenes and lactic acid bacteria in a model brine chiller system. Two concentrations of brine (7.9% [wt/wt] or 13.2% [wt/wt]) were inoculated with a ~6.0 log CFU/ml cocktail of L. monocytogenes or lactic acid bacteria and passed through a UV treatment system for 60 min. Three replications of each bacteria-and-brine combination were performed and resulted in at least a 4.5-log reduction in microbial numbers in all treated brines after exposure to UV light. Bacterial populations were significantly reduced after 5 min of exposure to UV light in the model brine chiller compared with the control, which received no UV light exposure (P < 0.05). The maximum rate of inactivation for both microorganisms in treated brines occurred between minutes 1 and 15 of UV exposure. Results indicate that in-line treatment of chill brines with UV light reduces the number of L. monocytogenes and lactic acid bacteria.

scholarly journals Viability of lactic acid bacteria in different components of Ogi with anti diarrhoeagenic E. coli activities

2019 ◽  
Vol 3 (6) ◽  
pp. 206-213
Author(s):  
Roseline Eleojo Kwasi ◽  
Iyanuoluwa Gladys Aremu ◽  
Qudus Olamide Dosunmu ◽  
Funmilola A. Ayeni
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Antimicrobial Properties ◽  
Culture Method ◽  
Antimicrobial Activities ◽  
Drying Methods ◽  
Bacterial Strains ◽  
E Coli ◽  
Log Reduction ◽  
Freeze Dried

Background: Ogi constitutes a rich source of lactic acid bacteria (LAB) with associated health benefits to humans through antimicrobial activities. However, the high viability of LAB in Ogi and its supernatant (Omidun) is essential. Aims: This study was carried out to assess the viability of LAB in various forms of modified and natural Ogi and the antimicrobial properties of Omidun against diarrhoeagenic E coli. Methods and Material: The viability of LAB was assessed in fermented Ogi slurry and Omidun for one month and also freeze-dried Ogi with and without added bacterial strains for two months. A further 10 days viability study of modified Omidun, refrigerated Omidun, and normal Ogi was performed. The antimicrobial effects of modified Omidun against five selected strains of diarrhoeagenic E. coli (DEC) were evaluated by the co-culture method. Results: Both drying methods significantly affected carotenoids and phenolic compounds. The Ogi slurry had viable LAB only for 10 days after which, there was a succession of fungi and yeast. Omidun showed 2 log10cfu/ml reduction of LAB count each week and the freeze-dried Ogi showed progressive reduction in viability. Refrigerated Omidun has little viable LAB, while higher viability was seen in modified Omidun (≥2 log cfu/ml) than normal Omidun. Modified Omidun intervention led to 2-4 log reduction in diarrhoeagenic E. coli strains and total inactivation of shigella-toxin producing E. coli H66D strain in co-culture. Conclusions: The consumption of Ogi should be within 10 days of milling using modified Omidun. There are practical potentials of consumption of Omidun in destroying E. coli strains implicated in diarrhea. Keywords: Ogi, Omidun, lactic acid bacteria, diarrhoeagenic Escherichia coli strains, Viability.

scholarly journals Evaluation of lactic acid bacteria viability and anti-diarrhoeagenic Escherichia coli activities of non-alcoholic fermented beverage ‘Kunu’

2021 ◽  
Vol 13 (1) ◽  
pp. 122-127
Author(s):  
Ayomide F. Sowemimo ◽  
Abiola O. Obisesan ◽  
Funmilola A. Ayeni
Keyword(s):  
Escherichia Coli ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Storage Conditions ◽  
Antimicrobial Activities ◽  
Rrna Gene ◽  
E Coli ◽  
Log Reduction ◽  
Fermented Beverage ◽  
Leuconostoc Pseudomesenteroides

Kunu is a non-alcoholic fermented cereal beverage consumed primarily as a refreshing drink. This study investigated the effects of storage conditions on viability of Lactic Acid Bacteria (LAB) in kunu and the antibacterial effects of Kunu against diarrhoea caused by Escherichia coli strains. Kunu was prepared according to local traditional method. Viability counts of LAB in kunu stored at two different conditions, cold (4 ℃ average) and room temperature (26 ℃ average), were evaluated. Isolated LAB from kunu were identified by partial sequencing of 16S rRNA gene. Five pathotypes of diarrhoea caused by E. coli strains were co-cultured with kunu to evaluate its antimicrobial activities. Viable LAB count in kunu ranged from 5.0 x 109 to 1.0 x 1011 cfu/mL. Pediococcus pentosaceus, Lactobacillus plantarum and Leuconostoc pseudomesenteroides were identified from kunu. There is a drastic decrease (2-5 log reduction) in E. coli strains co-cultured with kunu. The observed high viable counts of beneficial LAB in kunu with its antimicrobial activities against diarrhoeaogenic E. coli strains indicates that kunu is not just a refreshing drink, but it also has antimicrobial potential against diarrhoea caused by E. coli.

Quantifying Nonthermal Inactivation of Listeria monocytogenes in European Fermented Sausages Using Bacteriocinogenic Lactic Acid Bacteria or Their Bacteriocins: A Case Study for Risk Assessment

2006 ◽  
Vol 69 (11) ◽  
pp. 2648-2663 ◽  
Author(s):  
ELEFTHERIOS H. DROSINOS ◽  
MARIOS MATARAGAS ◽  
SLAVICA VESKOVIĆ-MORAČANIN ◽  
JUDIT GASPARIK-REICHARDT ◽  
MIRZA HADŽIOSMANOVIĆ ◽  
...  
Keyword(s):  
Risk Assessment ◽  
Lactic Acid ◽  
Listeria Monocytogenes ◽  
Lactic Acid Bacteria ◽  
Storage Temperature ◽  
Inactivation Kinetics ◽  
Initial Population ◽  
Log Reduction ◽  
Fermented Sausages

Listeria monocytogenes NCTC10527 was examined with respect to its nonthermal inactivation kinetics in fermented sausages from four European countries: Serbia-Montenegro, Hungary, Croatia, and Bosnia-Herzegovina. The goal was to quantify the effect of fermentation and ripening conditions on L. monocytogenes with the simultaneous presence or absence of bacteriocin-producing lactic acid bacteria (i.e., Lactobacillus sakei). Different models were used to fit the experimental data and to calculate the kinetic parameters. The best model was chosen based on statistical comparisons. The Baranyi model was selected because it fitted the data better in most (73%) of the cases. The results from the challenge experiments and the subsequent statistical analysis indicated that relative to the control condition the addition of L. sakei strains reduced the time required for a 4-log reduction of L. monocytogenes (t4D). In contrast, the addition of the bacteriocins mesenterocin Y and sakacin P decreased the t4D values for only the Serbian product. A case study for risk assessment also was conducted. The data of initial population and t4D collected from all countries were described by a single distribution function. Storage temperature, packaging method, pH, and water activity of the final products were used to calculate the inactivation of L. monocytogenes that might occur during storage of the final product (U.S. Department of Agriculture Pathogen Modeling Program version 7.0). Simulation results indicated that the addition of L. sakei strains significantly decreased the simulated L. monocytogenes concentration of ready-to-eat fermented sausages at the time of consumption.

Apple Juice Preservation Using Combined Nonthermal Processing and Antimicrobial Packaging

2021 ◽  
Author(s):  
Tony Jin ◽  
RAMADAN M. ABOELHAGGAG ◽  
Mingming Guo
Keyword(s):  
Electric Fields ◽  
Apple Juice ◽  
Uv Light ◽  
Antimicrobial Packaging ◽  
E Coli ◽  
Log Reduction ◽  
Nonthermal Processing ◽  
Soluble Solid ◽  
Pulsed Uv Light ◽  
Mold And Yeast

This study investigated the effectiveness of pulsed electric fields (PEF) treatment (19, 23, 30 kV/cm), pulsed UV light (PL) treatment (5 to 50 s; 1.04 J/cm 2 /s), and antimicrobial packaging (AP) treatment, either individually or combined, in inactivating bacteria and in maintaining the quality of fruit juices. Apple juice samples, inoculated with Escherichia coli K12 or native mold and yeast (M&Y), were treated by a bench scale PEF and/or PL processing systems and stored in glass jars with antimicrobial caps containing 10 µl of carvacrol (AP). The reduction in microbial populations and the physicochemical properties of juice samples were determined after treatments and during storage at 10°C. The treatments included PL (5 to 50 s; 1.04 J/cm 2 /s ), PEF (19, 23, 30 kV/cm), PEF followed by PL (PEF+PL), PL followed by PEF (PL+PEF), and PEF+PL+AP. PEF treatments from 19 to 30 kV/cm (PEF19, PEF23, PEF30) achieved E. coli reduction by 2.0, 2.6 and 4.0 log CFU/ml, respectively; PL treatments for 10 to 50 seconds (PL10, PL20, PL30, PL40, PL50) achieved E. coli reduction by 0.45, 0.67, 0.76, 2.3, and 4.0 log CFU/ml, respectively. There were no significant (p>0.05) differences between the combined PL20+PEF19 and PEF19+PL20 treatments; both treatments reduced E. coli K12 populations to non-detectable levels (> 5 log reduction) after 7 days. Both PEF+PL and PEF+PL+AP treatments achieved over 5 log reduction of M&Y; however, juice samples subject to PEF+PL+AP treatment had lower M&Y counts (2.9 log) than samples subject to PEF+PL treatment (3.9 log) after 7 days. There were no significant (p > 0.05) differences in pH, acidity, total soluble solid contents among all samples after treatments. Increased PL treatment times reduced color a*, b* values, total phenolics and carotenoid contents. This study provides valuable information to juice processors for consideration and design of nonthermal pasteurization of juice products.

Validation of Ground-and-Formed Beef Jerky Processes Using Commercial Lactic Acid Bacteria Starter Cultures as Pathogen Surrogates

2009 ◽  
Vol 72 (6) ◽  
pp. 1234-1247 ◽  
Author(s):  
ALENA G. BOROWSKI ◽  
STEVEN C. INGHAM ◽  
BARBARA H. INGHAM
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Starter Cultures ◽  
Simple Method ◽  
Process Validation ◽  
E Coli ◽  
Log Reduction ◽  
Heat Resistant ◽  
Beef Jerky ◽  
Whole Muscle

Beef jerky has been linked to multiple outbreaks of salmonellosis and Escherichia coli O157:H7 infection over the past 40 years. With increasing government scrutiny of jerky-making process lethality, a simple method by which processors can easily validate the lethality of their ground-and-formed beef jerky process against Salmonella and E. coli O157:H7 is greatly needed. Previous research with whole-muscle beef jerky indicated that commercial lactic acid bacteria (LAB) may be more heat resistant than Salmonella and E. coli O157:H7, suggesting the potential use of LAB as pathogen surrogates. Of six commercial LAB-containing cultures evaluated for heat resistance in ground-and-formed beef jerky, Saga 200 (Pediococcus spp.) and Biosource (Pediococcus acidilactici) were identified as consistently more heat resistant than Salmonella and E. coli O157:H7. Six representative ground-and-formed beef jerky commercial processes, differing widely in lethality, were used to identify an appropriate level of LAB reduction that would consistently indicate a process sufficiently lethal (≥5.0-log reduction) for Salmonella and E. coli O157:H7. Both Saga 200 and Biosource consistently predicted adequate process lethality with a criterion of ≥5.0-log reduction of LAB. When either LAB decreased by ≥5.0 log CFU, processes were sufficiently lethal against Salmonella and E. coli O157:H7 in 100% of samples (n = 39 and 40, respectively). Use of LAB as pathogen surrogates for ground-and-formed beef jerky process validation was field tested by three small meat processors, who found this technique easy to use for process validation.

Reduction of Escherichia coli O157:H7 and Salmonella in Ground Beef Using Lactic Acid Bacteria and the Impact on Sensory Properties

2005 ◽  
Vol 68 (8) ◽  
pp. 1587-1592 ◽  
Author(s):  
L. SMITH ◽  
J. E. MANN ◽  
K. HARRIS ◽  
M. F. MILLER ◽  
M. M. BRASHEARS
Keyword(s):  
Escherichia Coli ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Foodborne Pathogens ◽  
Ground Beef ◽  
Sensory Properties ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Log Reduction ◽  
The Impact

Studies were conducted to determine whether four strains of lactic acid bacteria (LAB) inhibited Escherichia coli O157: H7 and Salmonella in ground beef at 5°C and whether these bacteria had an impact on the sensory properties of the beef. The LAB consisted of frozen concentrated cultures of four Lactobacillus strains, and a cocktail mixture of streptomycin-resistant E. coli O157:H7 and Salmonella were used as pathogens. Individual LAB isolates at 107 CFU/ml were added to tryptic soy broth containing a pathogen concentration of 105 CFU/ml. Samples were stored at 5°C, and pathogen populations were determined on days 0, 4, 8, and 12. After 4 days of storage, there were significant differences in numbers of both pathogens exposed to LAB isolates NP 35 and NP 3. After 8 and 12 days of storage, all LAB reduced populations of both pathogens by an average of 3 to 5 log cycles. A second study was conducted in vacuum-packaged fresh ground beef. The individual LAB isolates resulted in an average difference of 1.5 log cycles of E. coli O157:H7 after 12 days of storage, and Salmonella populations were reduced by an average of 3 log cycles. Following this study, a mixed concentrated culture was prepared from all four LAB and added to ground beef inoculated with pathogen at 108 CFU/g. After 3 days of storage, the mixed culture resulted in a 2.0-log reduction in E. coli O157:H7 compared with the control, whereas after 5 days of storage, a 3-log reduction was noted. Salmonella was reduced to nondetectable levels after day 5. Sensory studies on noninoculated samples that contained LAB indicated that there were no adverse effects of LAB on the sensory properties of the ground beef. This study indicates that adding LAB to raw ground beef stored at refrigeration temperatures may be an important intervention for controlling foodborne pathogens.

scholarly journals Effect of UV-C Irradiation and Lactic Acid Application on the Inactivation of Listeria monocytogenes and Lactic Acid Bacteria in Vacuum-Packaged Beef

Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1217
Author(s):  
Giannina Brugnini ◽  
Soledad Rodríguez ◽  
Jesica Rodríguez ◽  
Caterina Rufo
Keyword(s):  
Lactic Acid ◽  
Listeria Monocytogenes ◽  
Lactic Acid Bacteria ◽  
Quadratic Model ◽  
Meat Color ◽  
Minimal Impact ◽  
Log Reduction ◽  
Combined Application ◽  
Meat Samples ◽  
Uv C

The objective of this study was to test the effect of the combined application of lactic acid (0–5%) (LA) and UV-C light (0–330 mJ/cm2) to reduce Listeria monocytogenes and lactic acid bacteria (LAB) on beef without major meat color (L *, a *, b *) change and its impact over time. A two-factor central composite design with five central points and response surface methodology (RSM) were used to optimize LA concentration and UV-C dose using 21 meat pieces (10 g) inoculated with L. monocytogenes (LM100A1). The optimal conditions were analyzed over 8 weeks. A quadratic model was obtained that predicted the L. monocytogenes log reduction in vacuum-packed beef treated with LA and UV-C. The maximum log reduction for L. monocytogenes (1.55 ± 0.41 log CFU/g) and LAB (1.55 ± 1.15 log CFU/g) with minimal impact on meat color was achieved with 2.6% LA and 330 mJ/cm2 UV-C. These conditions impaired L. monocytogenes growth and delayed LAB growth by 2 weeks in vacuum-packed meat samples throughout 8 weeks at 4 °C. This strategy might contribute to improving the safety and shelf life of vacuum-packed beef with a low impact on meat color.

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