Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- Essential oils (2)
- Non thermal technology (2)
- Ozone (2)
- Acid adaptation (1)
- Acid exposure (1)
-
- Antimicrobial (1)
- Antimicrobial activity; chemical compounds; plant/animal/microbial antimicrobials (1)
- Bubble column (1)
- Carrot (1)
- E coli (1)
- E. coli (1)
- Escherichia coli (1)
- Food composition (1)
- Food model (1)
- Lettuce (1)
- Mechanism; minimum inhibitory concentration (1)
- Microbial kinetics (1)
- Non-thermal inactivation (1)
- Orange juice (1)
- Ready-to-eat (1)
- Sensory Volatiles (1)
- Spoilage (1)
- Synergy (1)
- Ultrasound (1)
- Weibull model (1)
Articles 1 - 6 of 6
Full-Text Articles in Life Sciences
The Effects Of Acid Adaptation On Escherichia Coli Inactivation Using Power Ultrasound, Sonal Patil, Paula Bourke, Bridget Cullen, Jesus Maria Frias, Patrick Cullen
The Effects Of Acid Adaptation On Escherichia Coli Inactivation Using Power Ultrasound, Sonal Patil, Paula Bourke, Bridget Cullen, Jesus Maria Frias, Patrick Cullen
Articles
Inactivation of Escherichia coli in liquids was carried out using power ultrasound. Parameters examined included amplitude levels (0.4µm, 7.5 µm, 37.5 µm), treatment time, cell condition (non-adapted cells, acid adapted cells), liquid media (TSB, model orange juice and model apple juice) and E. coli strain (ATCC 25922, NCTC 12900). The efficacy of ultrasound treatment was found to be a function of amplitude level, treatment time and media (p0.95), with the highest inactivation achieved using an amplitude of 37.5 µm. The D-values of E. coli 25922 at all amplitudes in model orange juice were not significantly different than in TSB media. …
Impact Of Plant Essential Oils On Microbiological, Organoleptic And Quality Markers Of Minimally Processed Vegetables, Jorge Gutierrez, Paula Bourke, Julien Lonchamp, Catherine Barry-Ryan
Impact Of Plant Essential Oils On Microbiological, Organoleptic And Quality Markers Of Minimally Processed Vegetables, Jorge Gutierrez, Paula Bourke, Julien Lonchamp, Catherine Barry-Ryan
Articles
The objectives of this study were to evaluate the efficacy of plant essential oils (EOs) for control of the natural spoilage microflora on ready-to-eat (RTE) lettuce and carrots whilst also considering their impact on organoleptic properties. Initial decontamination effects achieved using EOs were comparable to that observed with chlorine and solution containing oregano recorded a significantly lower initial TVC level than the water treatment on carrots (p < 0.05). No significant differences were found between the EO treatments and chlorine considering gas composition, color, texture and water activity of samples. The sensory panel found EO treatments acceptable for carrots throughout storage, while lettuce washed with the EO solutions were rejected for overall appreciation by Day 7. Correlating microbial and sensory changes with volatile emissions identified 12 volatile quality markers. Oregano might be a suitable decontamination alternative to chlorine for RTE carrots, while the identification of volatile quality markers is a useful complement to sensory and microbiological assessments in the monitoring of organoleptic property changes and shelf-life of fresh vegetables. Industrial relevance There is industrial demand for natural alternatives to chlorine, which is commonly used for decontamination of fresh produce but which has limitations with respect to antimicrobial efficacy and possible formation of carcinogenic compounds in water. Plant essential oils have proven antimicrobial and other bioactive properties, however their usefulness in foods can be mitigated by their high sensory impact. This study examined the application of EOs for fresh produce decontamination addressing control of spoilage microflora and improving shelf-life characteristics whilst also considering the impact on organoleptic properties. The effectiveness of oregano as a decontamination treatment was comparable with that of chlorine. Carrot discs treated with the EO regimes were acceptable in terms of sensory quality and appreciation, therefore oregano could offer a natural alternative for the washing and preservation of fresh produce. Combining EOs with other natural preservatives might minimize doses and reduce the impact on organoleptic properties of fresh vegetables.
Extrinsic Control Parameters For Ozone Inactivation Of Escherichia Coli Using A Bubble Column, Sonal Patil, Patrick Cullen, Bridget Cullen, Jesus Maria Frias, Paula Bourke
Extrinsic Control Parameters For Ozone Inactivation Of Escherichia Coli Using A Bubble Column, Sonal Patil, Patrick Cullen, Bridget Cullen, Jesus Maria Frias, Paula Bourke
Articles
Aims: To investigate the effect of extrinsic control parameters for ozone inactivation of E. coli in a bubble column. Methods and Results: Ozone inactivation of Escherichia coli ATCC 25922 in Tryptic Soya Broth was examined. The parameters studied included temperature (ambient, 20, 25 and 30°C), exposure time (up to 30 min), gas flow rate (0·03, 0·06, 0·12, 0·25, 0·5 and 0·75 l min−1) and concentration level (five different levels). The efficacy of ozone treatment was a function of the parameters investigated and optimum control parameters of flow rate (0·12 l min−1), temperature (ambient) and ozone concentration (75 μg ml−1) resulted …
Application Of Natural Antimicrobials For Food Preservation, Brijesh Tiwari, Vasilis Valdramidis, Colm O' Donnell, Kasiviswanathan Muthukumarappan, Patrick Cullen, Paula Bourke
Application Of Natural Antimicrobials For Food Preservation, Brijesh Tiwari, Vasilis Valdramidis, Colm O' Donnell, Kasiviswanathan Muthukumarappan, Patrick Cullen, Paula Bourke
Articles
In this review, antimicrobials from a range of plant, animal, and microbial sources are reviewed 10 along with their potential applications in food systems. Chemical and biochemical antimicrobial 11 compounds derived from these natural sources and their activity against a range of pathogenic and 12 spoilage microorganisms pertinent to food, together with their effects on food organoleptic proper- 13 ties, are outlined. Factors influencing the antimicrobial activity of such agents are discussed 14 including extraction methods, molecular weight, and agent origin. These issues are considered in 15 conjunction with the latest developments in the quantification of the minimum inhibitory (and …
Antimicrobial Activity Of Plant Essential Oils Using Food Model Media: Efficacy, Synergistic Potential And Interaction With Food Components, Jorge Gutierrez, Catherine Barry-Ryan, Paula Bourke
Antimicrobial Activity Of Plant Essential Oils Using Food Model Media: Efficacy, Synergistic Potential And Interaction With Food Components, Jorge Gutierrez, Catherine Barry-Ryan, Paula Bourke
Articles
The aim of this study was to optimise the antimicrobial efficacy of plant essential oils (EOs) for control of Listeria spp. and spoilage bacteria using food model media based on lettuce, meat and milk. The EOs evaluated were lemon balm, marjoram, oregano and thyme and their minimum inhibitory concentrations (MIC) were determined against Enterobacter spp., Listeria spp., Lactobacillus spp., and Pseudomonas spp. using the agar dilution method and/or the absorbance based microplate assay. MICs were significantly lower in lettuce and beef media than in TSB. Listeria strains were more sensitive than spoilage bacteria, and oregano and thyme were the most …
Inactivation Of Escherichia Coli In Orange Juice Using Ozone, Sonal Patil, Paula Bourke, Jesus Maria Frias, Brijesh Tiwari, Patrick Cullen
Inactivation Of Escherichia Coli In Orange Juice Using Ozone, Sonal Patil, Paula Bourke, Jesus Maria Frias, Brijesh Tiwari, Patrick Cullen
Articles
This research investigated the efficacy of gaseous ozone for the inactivation of Escherichia coli ATCC 25922 and NCTC 12900 strains in orange juice. Orange juice inoculated with E. coli (106 CFU mL-1) as a challenge microorganism was treated with ozone at 75-78µg mL-1 for different time periods (0-18 min). The efficacy of ozone for inactivation of both strains of E. coli was evaluated as a function of different juice types: model orange juice, fresh unfiltered juice, juice without pulp, and juice filtered through 500mm or 1mm sieves. Fast inactivation rates for total reduction of E. coli …