Application of Neutral Electrolyzed Water on pork chops and its impact on meat quality

AbstractPhysicochemical and microbiological properties of pork chops sprayed with Neutral Electrolyzed Water (NEW) were evaluated during storage at refrigeration temperature. Pork chops were randomly allocated into three groups and were artificially contaminated with an inoculum of 106 CFU/mL of Listeria monocytogenes. Each group was treated with either NEW (58 ppm), NaClO (35 ppm), or saline solution (SS). Subsequently, recovered bacteria were plated on TSA petri dishes and the reduction percentage of Listeria monocytogenes was calculated 24 h and 8 days after treatment. Physicochemical analysis [pH, content of lactic acid, thiobarbituric acid reactive substances (TBARS) and total volatile base nitrogen (TVBN)] were performed to evaluate the effect of all solutions used on pork meat kept at 4 °C for 19 days. In vitro NEW reduced L. monocytogenes titers by > 99.98% and 80.19% and 90.35% in artificially contaminated pork 24 h and 8 days after NEW treatment, respectively. Compared to the SS treatment, NEW and NaClO solutions caused a 0.67 Log UFC/g and 0.65 Log UFC/g reduction respectively. After eight days post-treatment, NEW and NaClO bacterial titers were below the SS treatment. NEW caused little color change in treated meat. It helped to reduce the formation of lactic acid and TVB-N when pork chops are kept at 4 °C for 19 days. Therefore, NEW could be considered as a new alternative to sanitize and preserve pork meat.

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Physicochemical Parameters and Bioaccessibility of Lactic Acid Bacteria Fermented Chayote Leaf (Sechium edule) and Pineapple (Ananas comosus) Smoothies

Frontiers in Nutrition ◽

10.3389/fnut.2021.649189 ◽

2021 ◽

Vol 8 ◽

Author(s):

Millicent G. Managa ◽

Stephen A. Akinola ◽

Fabienne Remize ◽

Cyrielle Garcia ◽

Dharini Sivakumar

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Physicochemical Parameters ◽

Color Change ◽

Soluble Solids ◽

Ananas Comosus ◽

Carotenoid Content ◽

Overall Acceptability ◽

Total Carotenoid Content

In this study, popularly consumed traditional chayote leaves and locally produced pineapple fruit were used to develop a fermented smoothie using lactic acid bacteria (LAB) strains: Lactobacillus plantarum (L75), Weissella cibaria (W64), and their combination (LW64 + 75). The physicochemical parameters [pH, total soluble solids (TSS), and color], total phenols, and carotenoid contents of the smoothies fermented for 48 h and stored for 7 days at 4°C were compared with the unfermented (control) smoothies. Results indicated that LAB fermentation reduced the pH from 3.56 to 2.50 after 48 h (day 2) compared with the non-fermented smoothie at day 2 (pH 3.37). LAB strain L75 significantly reduced the TSS content of the smoothies to 13.06°Bx after 2 days of fermentation. Smoothies fermented by L75 showed overall acceptability after 7 days of storage compared with the non-fermented puree on day 0. The LW64 + 75 significantly reduced the color change (ΔE), which was similar to the control. L75 increased the phenolic content, and W64 enhanced the total carotenoid content of the smoothies after 2 days of fermentation compared with other treatments. The use of an in vitro model simulating gastrointestinal (GI) digestion showed that fermentation with L75 improved the total phenol recovery by 65.96% during the intestinal phase compared with the control. The dialysis phase mimicked an epithelial barrier, and 53.58% of the recovered free soluble are bioavailable from the L75 fermented smoothies compared with the control. The antioxidant capacity of dialyzable fraction of the L75 fermented smoothie was significantly higher than that of the control and smoothies fermented with W64 or LW64 + 75.

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In vitro evaluation of bacteriocin-like inhibitory substances produced by lactic acid bacteria isolated during traditional Sicilian cheese making

Italian Journal of Food Safety ◽

10.4081/ijfs.2016.5503 ◽

2016 ◽

Vol 5 (1) ◽

Cited By ~ 6

Author(s):

Giusi Macaluso ◽

Gerlando Fiorenza ◽

Raimondo Gaglio ◽

Isabella Mancuso ◽

Maria Luisa Scatassa

Keyword(s):

Lactic Acid ◽

Listeria Monocytogenes ◽

Lactic Acid Bacteria ◽

Salmonella Enteritidis ◽

Raw Milk ◽

Starter Cultures ◽

Proteinase K ◽

Alternative Methods ◽

Diffusion Assay

Bacteriocins are antimicrobial proteins produced by bacteria that inhibit with a bactericidal or bacteriostatic mode of action, the growth of other bacteria. Many lactic acid bacteria (LAB) produce a high diversity of different bacteriocins. Bacteriocinogenic LAB are generally recognized as safe (GRAS) and useful to control the frequent development of pathogens and spoilage microorganisms; for this reason they are commonly used as starter cultures in food fermentations. In this study, the authors describe the results of a screening on 699 LAB isolated from wooden vat surfaces, raw milk and traditional Sicilian cheeses, for the production of bacteriocin-like inhibitory substances (BLIS), by comparing two alternative methods. The antagonistic activity of LAB and its proteinaceous nature were evaluated using the spot on the lawn and the well-diffusion assay and the sensitivity to proteolytic (proteinase K, protease B and trypsin), amylolytic (α-amylase) and lipolytic (lipase) enzymes. The indicator strains used were: Listeria monocytogenes, Staphylococcus aureus, E. coli, Salmonella enteritidis. A total of 223 strains (belonged to the species Enterococcus spp., Lactobacillus spp., Pediococcus spp., Streptococcus spp., Leuconostoc spp. and Lactococcus lactis) were found to inhibit the growth of Listeria monocytogenes by using the spot on the lawn method; only 37 of these were confirmed by using the well-diffusion assay. The direct addition of bacteriocin-producing cultures into dairy products can be a more practical and economic option for the improvement of the safety and quality of the final product.

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Growth and Survival of Listeria monocytogenes in Vacuum-Packaged Ground Beef Inoculated with Lactobacillus alimentarius FloraCarn L-2

Journal of Food Protection ◽

10.4315/0362-028x-61.5.551 ◽

1998 ◽

Vol 61 (5) ◽

pp. 551-556 ◽

Cited By ~ 32

Author(s):

BENJAMIN J. JUVEN ◽

SUSAN F. BAREFOOT ◽

MERLE D. PIERSON ◽

LINDA H. McCASKILL ◽

BRIAN SMITH

Keyword(s):

Hydrogen Peroxide ◽

Lactic Acid ◽

Listeria Monocytogenes ◽

Ground Beef ◽

Resistant Mutant ◽

Antibiotic Resistant ◽

Growth And Survival ◽

Ca 50 ◽

Psychrotrophic Strain

A culture of the psychrotrophic strain FloraCarn L-2 of Lactobacillus alimentarius was added to ground beef (pH 5.4) inoculated with two isolates of Listeria monocytogenes able to grow in refrigerated ground beef. The ground beef was vacuum-packaged and stored for 9 weeks at 4°C. Populations of inoculated L. monocytogenes initially were 6.3 to 6.4 log10 CFU/g and increased to 7.4 log10 CFU/g in ground beef with no added lactobacilli. Addition of L. alimentarius L-2 or its antibiotic-resistant mutant SRL-2 reduced the final populations of L. monocytogenes to 4.3 or 4.1 log10 CFU/g, respectively. L. alimentarius L-2 did not produce bacteriocins or hydrogen peroxide in vitro. The antilisterial effect of L. alimentarius observed in laboratory media and ground beef is attiibuted to lactic acid (ca. 50 mM) produced by growing cultures.

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Antimicrobial action of flavonoids from Sedum aizoon L. against lactic acid bacteria in vitro and in refrigerated fresh pork meat

Journal of Functional Foods ◽

10.1016/j.jff.2017.09.030 ◽

2018 ◽

Vol 40 ◽

pp. 744-750 ◽

Cited By ~ 8

Author(s):

Feng Xu ◽

Chunxing Wang ◽

Hongfei Wang ◽

Qian Xiong ◽

Yingying Wei ◽

...

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Antimicrobial Action ◽

Pork Meat ◽

Sedum Aizoon

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In Vitro Effect of Denture Cleansers on the Color Stability of Polyetheretherketone and Other Denture Base Polymers

Odovtos - International Journal of Dental Sciences ◽

10.15517/ijds.2021.47335 ◽

2021 ◽

pp. 284-293

Author(s):

Samet Tekin

Keyword(s):

Color Change ◽

Color Stability ◽

Chemical Compositions ◽

Denture Base ◽

Color Changes ◽

All Solutions ◽

Significant Difference ◽

Denture Cleansers

The aim of this in vitro study was to compare the long-term effect of overnight use of denture cleansers with different chemical compositions on the color stability of denture base polymers (DBPs). The four DBPs evaluated were PEEK (PK group), thermoinjection-molded polyamide (PA group), auto-polymerized polymethylmethacrylate (PMMA) (AP group), and heat-polymerized resin PMMA (HP group). The cleaning agents used were Corega tablet (CT), Protefix tablet (PT), and 0.5% sodium hypochlorite (NaOCl) solution (SH). Distilled water (DW) served as a control. Forty-eight disc-shaped specimens (10mm × 2mm) were prepared from each DBP and randomly immersed in the different storage media (n=12 in each group). Color measurements of the specimens before and after immersion in the denture cleansers were made using a spectrophotometer (VITA Easyshade V). The color changes were measured and recorded in L* a* b*. After 120 d, the CIEDE2000 formula was used to calculate color changes (∆E00). For analysis of the data, a multivariate analysis of variance was used (p<0.05). The results of the statistical analysis revealed significant color change differences in the DBPs immersed in the various denture cleansers (p<0.05). Groups PA and PK showed the highest values for all solutions. AP-SH showed the highest ∆E00 value in group AP, no significant difference was found between other solutions. In group HP, there was no statistically significant difference between the average ∆E00 values of all solutions. Long-term daily use of the denture cleansers affected the color stability of all the DBPs, although the level of color change was acceptable. Laboratory and clinical studies on the color stability of PEEK are needed to confirm the results of this study.

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Control of Listeria monocytogenes on Vacuum-Packaged Frankfurters Sprayed with Lactic Acid Alone or in Combination with Sodium Lauryl Sulfate

Journal of Food Protection ◽

10.4315/0362-028x-71.4.728 ◽

2008 ◽

Vol 71 (4) ◽

pp. 728-734 ◽

Cited By ~ 25

Author(s):

OLEKSANDR A. BYELASHOV ◽

PATRICIA A. KENDALL ◽

KEITH E. BELK ◽

JOHN A. SCANGA ◽

JOHN N. SOFOS

Keyword(s):

Lactic Acid ◽

Listeria Monocytogenes ◽

Sodium Lauryl Sulfate ◽

Growth Curves ◽

Lag Phase ◽

Lauryl Sulfate ◽

Phase Duration ◽

Poultry Products ◽

All Solutions ◽

Pathogen Populations

U.S. regulations require that processors employ lethal or inhibitory antimicrobial alternatives in production of ready-toeat meat and poultry products that support growth of Listeria monocytogenes and may be exposed to the processing environment after a lethality treatment. In this study, lactic acid (LA; 5%, vol/vol) and sodium lauryl sulfate (SLS; 0.5%, wt/vol) were evaluated individually or as a mixture (LASLS) for control of L. monocytogenes on frankfurters. Frankfurters were inoculated with a 10-strain mixture of L. monocytogenes, sprayed for 10 s (20 bar, 23 ± 2°C) with antimicrobials or distilled water (DW) before (LASLS or DW) or after (LA, SLS, LASLS, or DW) inoculation (4.8 ± 0.1 log CFU/cm2), vacuum packaged, and stored at 4°C for 90 days. Samples were analyzed for numbers of the pathogen (on PALCAM agar) and for total microbial counts (on tryptic soy agar with yeast extract) during storage. Spraying with DW, LA, or SLS after inoculation reduced numbers of L. monocytogenes by 1.3 ± 0.2, 1.8 ± 0.5, and 2.0 ± 0.4 log CFU/cm2, respectively. The LASLS mixture applied before or after inoculation reduced pathogen populations by 1.8 ± 0.4 and 2.8 ± 0.2 log CFU/cm2, respectively. No further reduction by any treatment was observed during storage. The bacterial growth curves (fitted by the model of Baranyi and Roberts) indicated that the lag-phase duration of the bacterium on control samples (13.85 to 15.18 days) was extended by spraying with all solutions containing LA. For example, LA suppressed growth of L. monocytogenes for 39.14 to 41.01 days. Pathogen growth rates also were lower on frankfurters sprayed after inoculation with LA or LASLS compared to those sprayed with DW. Therefore, spraying frankfurters with a mixture of LA and SLS may be a useful antilisterial alternative treatment for ready-to-eat meat and poultry products.

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Inhibition of Listeria monocytogenes by Milk Culture Filtrates from Lactobacillus delbrueckii subsp. lactis

Journal of Food Protection ◽

10.4315/0362-028x-55.7.542 ◽

1992 ◽

Vol 55 (7) ◽

pp. 542-544 ◽

Cited By ~ 11

Author(s):

GEORGE THARRINGTON ◽

KENT M. SORRELLS

Keyword(s):

Hydrogen Peroxide ◽

Lactic Acid ◽

Listeria Monocytogenes ◽

Causative Factor ◽

Lactobacillus Delbrueckii ◽

Culture Filtrates ◽

In Vitro Inhibition ◽

Lactobacillus Delbrueckii Subsp

Milk culture filtrates from Lactobacillus delbrueckii subsp. lactis were found to be inhibitory to test strains of Listeria monocytogenes. Effective in vitro inhibition was found in broth cultures and well diffusion assays. The causative factor(s) of inhibition was lactic acid and hydrogen peroxide.

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Starch Edible Films/Coatings Added with Carvacrol and Thymol: In Vitro and In Vivo Evaluation against Colletotrichum gloeosporioides

Foods ◽

10.3390/foods10010175 ◽

2021 ◽

Vol 10 (1) ◽

pp. 175 ◽

Cited By ~ 1

Author(s):

Carlos Enrique Ochoa-Velasco ◽

Julio César Pérez-Pérez ◽

José Mauricio Varillas-Torres ◽

Addí Rhode Navarro-Cruz ◽

Paola Hernández-Carranza ◽

...

Keyword(s):

Colletotrichum Gloeosporioides ◽

Color Change ◽

Edible Films ◽

Physicochemical Analysis ◽

Lag Phase ◽

In Vivo Evaluation ◽

Vitro Assay ◽

Starch Films

The aim of this work was to evaluate the in vitro and in vivo effectiveness of thymol and carvacrol added to edible starch films and coatings against Colletotrichum gloeosporioides. In vitro evaluation consisted of determining minimal inhibitory concentration (MIC) of carvacrol and thymol was determined at different pH values against Colletotrichum gloeosporioides. With MIC values, binary mixtures were developed. From these results, two coatings formulations were in vivo evaluated on mango and papaya. Physicochemical analysis, color change, fruit lesions and C. gloeosporioides growth were determined during storage. In vitro assay indicated that the MIC value of carvacrol and thymol against C. gloeosporioides was 1500 mg/L at pH 5. An additive effect was determined with 750/750 and 1125/375 mg/L mixtures of carvacrol and thymol, respectively. Coated fruits with selected mixtures of carvacrol and thymol presented a delay in firmness, maturity index and color change. Moreover, a fungistatic effect was observed due to a reduction of lesions in coated fruits. These results were corroborated by the increase in the lag phase value and the reduction of the growth rate. Carvacrol and thymol incorporated into edible films and coatings are able to reduce the incidence of anthracnose symptoms on mango and papaya.

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