The Experts below are selected from a list of 35493 Experts worldwide ranked by ideXlab platform
Luanne Leistner - One of the best experts on this subject based on the ideXlab platform.
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Food Preservation by combined methods
Food Research International, 2003Co-Authors: Luanne LeistnerAbstract:Abstract Foods preserved by combined methods remain stable and safe even without refrigeration, and are high in sensory and nutritive properties due to the gentle processes applied. The concept is gaining ground in industrialized as well as in developing countries. Several topics will be discussed briefly: (1) water activity, (2) hurdle effect, (3) hurdle technology (4) shelf stable products, (5) intermediate moisture Foods, and (6) perspectives.
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basic aspects of Food Preservation by hurdle technology
International Journal of Food Microbiology, 2000Co-Authors: Luanne LeistnerAbstract:Hurdle technology is used in industrialized as well as in developing countries for the gentle but effective Preservation of Foods. Previously hurdle technology, i.e., a combination of Preservation methods, was used empirically without much knowledge of the governing principles. Since about 20 years the intelligent application of hurdle technology became more prevalent, because the principles of major preservative factors for Foods (e.g., temperature, pH, a , Eh, competitive flora), w and their interactions, became better known. Recently, the influence of Food Preservation methods on the physiology and behaviour of microorganisms in Foods, i.e. their homeostasis, metabolic exhaustion, stress reactions, are taken into account, and the novel concept of multitarget Food Preservation emerged. In the present contribution a brief introduction is given on the potential hurdles for Foods, the hurdle effect, and the hurdle technology. However, emphasis is placed on the homeostasis, metabolic exhaustion, and stress reactions of microorganisms related to hurdle technology, and the prospects of the future goal of a multitarget Preservation of Foods. © 2000 Elsevier Science B.V. All rights reserved.
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Food Preservation by hurdle technology
Trends in Food Science and Technology, 1995Co-Authors: Luanne Leistner, Leon G M GorrisAbstract:Abstract Hurdle technology was developed several years ago as a new concept for the production of safe, stable, nutritious, tasty and economical Foods. It advocates the intelligent use of combinations of different Preservation factors or techniques (‘hurdles’) in order to achieve multi-target, mild but reliable Preservation effects. Attractive applications have been identified in many Food areas. The present article briefly introduces the concept of hurdle technology, presents potential applications and gives details on a recently concluded study concerned with this topic and to which scientists from 11 European countries have contributed.
Cornelis Versteeg - One of the best experts on this subject based on the ideXlab platform.
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quality related enzymes in plant based products effects of novel Food processing technologies part 3 ultrasonic processing
Critical Reviews in Food Science and Nutrition, 2015Co-Authors: Netsanet Shiferaw Terefe, Roman Buckow, Cornelis VersteegAbstract:High-power ultrasound is a versatile technology which can potentially be used in many Food processing applications including Food Preservation. This is part 2 of a series of review articles dealing with the effectiveness of nonthermal Food processing technologies in Food Preservation focusing on their effect on enzymes. Typically, ultrasound treatment alone does not efficiently cause microbial or enzyme inactivation sufficient for Food Preservation. However, combined with mild heat with or without elevated pressure (P ≤ 500 kPa), ultrasound can effectively inactivate enzymes and microorganisms. Synergistic effects between ultrasound and mild heat have been reported for the inactivation of both enzymes and microorganisms. The application of ultrasound has been shown to enhance the rate of inactivation of quality degrading enzymes including pectin methylesterase (PME), polygalacturonase (PG), peroxidase (POD), polyphenol oxidase (PPO), and lipoxygenase (LOX) at mild temperature by up to 400 times. Moreover, ultrasound enables the inactivation of relatively heat-resistant enzymes such as tomato PG1 and thermostable orange PME at mild temperature conditions. The extent to which ultrasound enhances the inactivation rate depends on the type of enzyme, the medium in which the enzyme is suspended, and the processing condition including frequency, ultrasonic intensity, temperature, and pressure. The physical and chemical effects of cavitation are considered to be responsible for the ultrasound-induced inactivation of enzymes, although the dominant mechanism depends on the structure of the enzyme.
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advances in innovative processing technologies for microbial inactivation and enhancement of Food safety pulsed electric field and low temperature plasma
Trends in Food Science and Technology, 2009Co-Authors: J Wan, John Coventry, Piotr Swiergon, Peerasak Sanguansri, Cornelis VersteegAbstract:The need for enhancing microbial Food safety and quality, without compromising the nutritional, functional and sensory characteristics of Foods, has created an increasing world-wide interest in low-temperature innovative processes for Food Preservation. In contrast, to the traditional thermal processes, these emerging technologies are predominantly reliant on physical processes, including high hydrostatic pressures, pulsed electric fields and low-temperature plasmas that inactivate microorganisms at ambient or moderately elevated temperatures and short treatment times. The current review presents the latest developments in the two most recent of these technologies, pulsed electric field and low-temperature plasma treatments for Food Preservation and disinfection of Food contact surfaces.
Fabrizio Leonforte - One of the best experts on this subject based on the ideXlab platform.
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active refrigeration technologies for Food Preservation in humanitarian context a review
Sustainable Energy Technologies and Assessments, 2017Co-Authors: Niccolò Aste, Claudio Del Pero, Fabrizio LeonforteAbstract:Abstract Food Preservation is one of the most neglected pillars of Food security in humanitarian context. In particular, few Preservation practices for both raw and cooked Food are in place, due to the lack of appropriate technologies, very limited access to energy, especially electricity, and affordability. This situation is quite common not only in humanitarian settings, but also in all the countries with very limited access to modern forms of energy, like majority of Sub-Saharan Africa and part of Asia. In general, Food Preservation in areas without access to power grid can be provided through active/passive refrigeration, characterized respectively by the use or not of an energy source such as electricity or fuels to run the refrigeration process. Currently, off-grid active refrigeration technologies have a high potential, but in commercial solutions there are still room for improvement. In such context, this work aims at presenting a comprehensive review of scientific and grey literature on active refrigeration technologies for Food Preservation and related practices, also describing relevant experiences focused to the implementation of innovative refrigeration systems in humanitarian contexts. In detail, the first part of the work takes in consideration the capability of refrigeration to preserve different types of Foods in various boundary conditions. The second part deeply analyses different active refrigeration technologies, comparing the solutions under an economic, technical and social point of view, also reporting some representative experiences within humanitarian projects to demonstrate pros and cons of various possible solutions. In the last part of the work an overall comparison and main recommendations are provided in order to identify the best technology for each specific application context, highlighting at the same time where the need of further research has to be mainly focused.
Barry G. Swanson - One of the best experts on this subject based on the ideXlab platform.
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non thermal Food Preservation pulsed electric fields
Trends in Food Science and Technology, 1997Co-Authors: Humberto Vegamercado, M M Gongoranieto, Gustavo V Barbosacanovas, Olga Martinbelloso, Bailin Qin, Fujung Chang, Barry G. SwansonAbstract:The use of electric discharges to inactivate microorganisms and enzymes in Food products has evolved since the 1920s from the ‘ElectroPure process’ (ohmic heating process) to the use of high-intensity pulsed electric fields in the 1990s. The non-thermal inactivation of microorganisms and enzymes using electric fields was demonstrated in the 1960s with a variety of microorganisms suspended in simulated Food systems. A variety of liquid Foods and beverages, including orange, apple and peach juices, pea soup, beaten eggs and skim milk, has been successfully processed during the 1980s and 1990s by several research groups. Little by little, the Food industry is demonstrating increasing interest in this promising emerging technology; furthermore, it is expected that it will soon be adopted to process several liquid Food products.
Rafael Pagan - One of the best experts on this subject based on the ideXlab platform.
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emerging mutant populations of listeria monocytogenes egd e under selective pressure of thymbra capitata essential oil question its use in Food Preservation
Food Research International, 2021Co-Authors: Daniel Berdejo, Diego Garciagonzalo, Elisa Pagan, Natalia Merino, Rafael PaganAbstract:Abstract Due to their excellent antimicrobial properties, essential oils (EO) have been proposed as potential preservatives for certain kinds of Foods, such as dairy products. However, the occurrence of pathogenic populations that are resistant to EOs could pose a health risk. This report seeks to assess the emergence of resistant populations in Listeria monocytogenes EGD-e growth at 37 °C under selective pressure of Thymbra capitata EO (TCO), to characterise their resistance in laboratory media, and to identify their genotypic changes, as well as to evaluate the resistance in skimmed milk. TCO cyclic treatment allowed the isolation of two L. monocytogenes EGD-e resistant strains against the EO: LmSTCO by sublethal doses (75 µL/L TCO) and LmLTCO by lethal doses (300 µL/L TCO) after 20 and 30 cycles, respectively. Both strains displayed an increase of the minimum inhibitory and bactericidal concentration against TCO and a higher survival rate after lethal treatments than the wild-type strain (LmWT). Growth kinetics revealed a better adaptation of LmSTCO in presence of TCO, while LmLTCO grew more slowly compared to LmWT, even in the absence of the antimicrobial. Moreover, a slight increase in cross-resistance to antibiotics was observed: LmSTCO to β-lactams and LmLTCO to a series of broad-spectrum antibiotics. The genomic study revealed one sole nucleotide change in LmSTCO located in plsC gene codifying an enzyme involved in the production of phosphatidic acid, a precursor in cell membrane synthesis. Five genetic variations were found in LmLTCO: among them, the deletion of an ATP-synthesis system involved in slowing bacterial growth. Inhibition and inactivation assays in skimmed milk confirmed the increased resistance of both strains, thereby indicating a safety risk in case these strains emerge in the Food chain. These results strongly suggest that the occurrence of such resistances should be taken into account in order to ensure the efficacy of natural antimicrobials in the design of Food Preservation strategies.
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chemical composition and antioxidant properties of laurus nobilis l and myrtus communis l essential oils from morocco and evaluation of their antimicrobial activity acting alone or in combined processes for Food Preservation
Journal of the Science of Food and Agriculture, 2014Co-Authors: Lamia Cherrat, Laura Espina, Rafael Pagan, Diego Garciagonzalo, Mohammed Bakkali, Amin LaglaouiAbstract:BACKGROUND: This study describes the antioxidant and antimicrobial activity of Laurus nobilis L. and Myrtus communis L. essential oils (EOs). This is the first report of the synergistic antimicrobial effect of these EOs in combination with physical Food Preservation treatments. RESULTS: EOs obtained by steam distillation from aerial parts of Laurus nobilis and Myrtus communis were analysed by using gas chromatography – mass spectrometry. The main compounds were 1,8-cineole and 2-carene (L. nobilis EO); and myrtenyl acetate, 1,8-cineole and α-pinene (M. communis EO). L. nobilis EO showed higher antioxidant activity than M. communis EO in three complementary antioxidant tests. Although antimicrobial activity tests demonstrated the effectiveness of L. nobilis EO and the lack of bactericidal effect of M.communis EO, synergistic lethal effects were observed when combining each EO (0.2 µL mL −1 ) with mild heat (54 ◦ C for 10 min) or high hydrostatic pressure (175 – 400 MPa for 20 min). In contrast, combination of EOs with pulsed electric fields (30 kV cm −1 for 25 pulses) showed no additional effects. CONCLUSION: This study shows the great potential of these EOs in combined treatments with mild heat and high hydrostatic pressure to obtain a higher inactivation of Foodborne pathogens, which might help in the design of safe processes applied at low intensity. c � 2013 Society of Chemical Industry
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mechanism of bacterial inactivation by limonene and its potential use in Food Preservation combined processes
PLOS ONE, 2013Co-Authors: Laura Espina, Tilahun K Gelaw, Silvia De Lamocastellvi, Rafael Pagan, Diego GarciagonzaloAbstract:This work explores the bactericidal effect of (+)-limonene, the major constituent of citrus fruits' essential oils, against E. coli. The degree of E. coli BJ4 inactivation achieved by (+)-limonene was influenced by the pH of the treatment medium, being more bactericidal at pH 4.0 than at pH 7.0. Deletion of rpoS and exposure to a sub-lethal heat or an acid shock did not modify E. coli BJ4 resistance to (+)-limonene. However, exposure to a sub-lethal cold shock decreased its resistance to (+)-limonene. Although no sub-lethal injury was detected in the cell envelopes after exposure to (+)-limonene by the selective-plating technique, the uptake of propidium iodide by inactivated E. coli BJ4 cells pointed out these structures as important targets in the mechanism of action. Attenuated Total Reflectance Infrared Microspectroscopy (ATR-IRMS) allowed identification of altered E. coli BJ4 structures after (+)-limonene treatments as a function of the treatment pH: β-sheet proteins at pH 4.0 and phosphodiester bonds at pH 7.0. The increased sensitivity to (+)-limonene observed at pH 4.0 in an E. coli MC4100 lptD4213 mutant with an increased outer membrane permeability along with the identification of altered β-sheet proteins by ATR-IRMS indicated the importance of this structure in the mechanism of action of (+)-limonene. The study of mechanism of inactivation by (+)-limonene led to the design of a synergistic combined process with heat for the inactivation of the pathogen E. coli O157:H7 in fruit juices. These results show the potential of (+)-limonene in Food Preservation, either acting alone or in combination with lethal heat treatments.