The Experts below are selected from a list of 6729 Experts worldwide ranked by ideXlab platform
Olga Martinbelloso - One of the best experts on this subject based on the ideXlab platform.
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control of pathogenic and Spoilage Microorganisms in fresh cut fruits and fruit juices by traditional and alternative natural antimicrobials
2009Co-Authors: Rosa M Raybaudimassilia, Jonathan Mosquedamelgar, Robert Solivafortuny, Olga MartinbellosoAbstract:ABSTRACT: Traditional antimicrobials have been extensively used for many years. However, consumers are currently demanding wholesome, fresh-like, and safe foods without addition of chemically synthesized preservatives. The application of novel natural antimicrobials to assure safety of fresh-cut fruits and unpasteurized juices while preventing quality loss is a promising alternative. The effectiveness of these natural substances added to fruit derivatives has been studied by different researchers. Antimicrobials of animal (lactoperoxidase, lysozyme, and chitosan), plant (essential oils, aldehydes, esters, herbs, and spices), and microbial origin (nisin) can be used to effectively reduce pathogenic and Spoilage Microorganisms in fresh-cut fruits and fruit juices. Nevertheless, the use of these compounds at a commercial level is still limited due to several factors such as impact on sensory attributes or, in some cases, regulatory issues concerning their use. Therefore, extensive research on the effects of each antimicrobial on food sensory characteristics is still needed so that antimicrobial substances of natural origin can be regarded as feasible alternatives to synthetic ones.
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optimising the inactivation of grape juice Spoilage organisms by pulse electric fields
2009Co-Authors: Robert A Marsellesfontanet, Anna Puig, P Olmos, Santiago Minguezsanz, Olga MartinbellosoAbstract:Abstract The effect of some pulsed electric field (PEF) processing parameters (electric field strength, pulse frequency and treatment time), on a mixture of Microorganisms (Kloeckera apiculata, Saccharomyces cerevisiae, Lactobacillus plantarum, Lactobacillus hilgardii and Gluconobacter oxydans) typically present in grape juice and wine were evaluated. An experimental design based on response surface methodology (RSM) was used and results were also compared with those of a factorially designed experiment. The relationship between the levels of inactivation of Microorganisms and the energy applied to the grape juice was analysed. Yeast and bacteria were inactivated by the PEF treatments, with reductions that ranged from 2.24 to 3.94 log units. All PEF parameters affected microbial inactivation. Optimal inactivation of the mixture of Spoilage Microorganisms was predicted by the RSM models at 35.0 kV cm− 1 with 303 Hz pulse width for 1 ms. Inactivation was greater for yeasts than for bacteria, as was predicted by the RSM. The maximum efficacy of the PEF treatment for inactivation of Microorganisms in grape juice was observed around 1500 MJ L− 1 for all the Microorganisms investigated. The RSM could be used in the fruit juice industry to optimise the inactivation of Spoilage Microorganisms by PEF.
Randy W Worobo - One of the best experts on this subject based on the ideXlab platform.
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inactivation of salmonella enterica and Spoilage Microorganisms in orange juice treated with dimethyl dicarbonate dmdc
2018Co-Authors: Rebecca M Cheng, John J Churey, Randy W WoroboAbstract:Abstract Salmonella enterica is the pertinent pathogen associated with orange juice products that have resulted in numerous foodborne outbreaks. Although fresh orange juice typically has a pH below 4.0, which inhibits most pathogen growth, S. enterica can survive at low pH for extended periods. Additionally, fresh juice contains Spoilage Microorganisms such as natural yeasts and molds, which can grow at low pH, and may cause fermentation and product Spoilage if left untreated. Numerous Salmonella outbreaks linked to fresh orange juice, as well as the burden of product Spoilage, have generated increased demand for alternative, non-thermal treatments that can ensure pathogen- and Spoilage-free products. In this study, the effect of dimethyl dicarbonate (DMDC) on pathogen and Spoilage microorganism inactivation in orange juice has been investigated with two experiments. First, pasteurized orange juice was inoculated with approximately 106–107 CFU/ml of five serotypes of S. enterica per ml and treated with DMDC to test the effectiveness of inactivation against Salmonella. For the fungal Spoilage microorganism study, fresh orange juice was held at room temperature to increase natural yeast and mold count to roughly 105–106 CFU/ml, followed with treatment with DMDC. DMDC at two concentrations (172 and 200 ppm) was used, and the tests were carried out at ambient (21 °C ± 3 °C) and refrigeration (4 °C) temperatures. There was a >5-log reduction of Salmonella at 4 °C after 24 h at both 172 and 200 ppm of DMDC. For the treatment of fungal Spoilage Microorganisms, a nearly 5 and 4 log reduction of yeasts and molds was observed at ambient temperature and 4 °C, respectively. These results suggest that DMDC is most effective for use under the 4 °C holding conditions to inactivate S. enterica, and should be coupled with an additional preservative system for fungal Spoilage control to produce safe orange juice that retains fresh quality.
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fungal Spoilage in food processing
2018Co-Authors: Abigail B Snyder, Randy W WoroboAbstract:Food processing, packaging, and formulation strategies are often specifically designed to inhibit or control microbial growth to prevent Spoilage. Some of the most restrictive strategies rely solely or on combinations of pH reduction, preservatives, water activity limitation, control of oxygen tension, thermal processing, and hermetic packaging. In concert, these strategies are used to inactivate potential Spoilage Microorganisms or inhibit their growth. However, for select microbes that can overcome these controls, the lack of competition from additional background microbiota helps facilitate their propagation.
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uv tolerance of Spoilage Microorganisms and acid shocked and acid adapted escherichia coli in apple juice treated with a commercial uv juice processing unit
2016Co-Authors: Jessie Usaga, Olga I Padillazakour, Randy W WoroboAbstract:ABSTRACT The enhanced thermal tolerance and survival responses of Escherichia coli O157:H7 in acid and acidified foods is a major safety concern for the production of low-pH products, including beverages. Little is known about this phenomenon when using UV light treatments. This study was conducted to evaluate the effects of strain (E. coli O157:H7 strains C7927, ATCC 35150, ATCC 43895, and ATCC 43889 and E. coli ATCC 25922) and physiological state (control-unadapted, acid adapted, and acid shocked) on the UV tolerance of E. coli in apple juice treated under conditions stipulated in current U.S. Food and Drug Administration regulations. A greater than 5-log reduction of E. coli was obtained under all tested conditions. A significant effect of strain (P < 0.05) was observed, but the physiological state did not influence pathogen inactivation (P ≥ 0.05). The UV sensitivity of three Spoilage Microorganisms (Aspergillus niger, Penicillium commune, and Alicyclobacillus acidoterrestris) was also determined at U...
Dennis J Damico - One of the best experts on this subject based on the ideXlab platform.
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effect of modified atmosphere packaging on the growth of Spoilage Microorganisms and listeria monocytogenes on fresh cheese
2018Co-Authors: Stephanie R B Brown, Emily C Forauer, Dennis J DamicoAbstract:ABSTRACT Queso Fresco has a limited shelf life and has been shown to support the rapid growth of Listeria monocytogenes during refrigerated storage. In addition to improving quality and extending shelf life, modified atmosphere packaging (MAP) has been used to control the growth of pathogenic Microorganisms in foods. The objectives of this study were to determine the effects of MAP conditions on the survival and growth of Spoilage Microorganisms and L. monocytogenes during storage of Queso Fresco manufactured without starter cultures. For L. monocytogenes experiments, cheeses were surface inoculated at ∼4 log10 cfu/g before packaging. Inoculated and uninoculated (shelf life experiments) cheeses were placed in 75-µm high-barrier pouches, packaged under 1 of 7 conditions including air, vacuum, or combinations of N2 and CO2 [100% N2 (MAP1), 30% CO2:70% N2 (MAP2), 50% CO2:50% N2 (MAP3), or 70% CO2:30% N2 (MAP4), 100% CO2 (MAP5)], and stored at 7°C. Samples were removed weekly through 35 d of storage. Listeria monocytogenes counts were determined for inoculated samples. Uninoculated samples were assayed for mesophilic and psychrotolerant counts, lactic acid bacteria, coliforms, and yeast and mold. In general, cheeses packaged under conditions consisting of higher contents of CO2 had lower pH levels during storage compared with those stored in conditions with lower levels or no CO2 at all. Similarly, the antimicrobial efficacy of MAP in controlling Spoilage Microorganisms increased with increasing CO2 content, whereas conditions consisting of 100% N2, vacuum, or air were less effective. Mean L. monocytogenes counts remained near inoculation levels for all treatments at d 1 but increased ∼2 log10 cfu/g on cheeses packaged in air, vacuum, and 100% N2 (MAP1) conditions at d 7 and an additional ∼1.5 log10 cfu/g at d 14 where they remained through 35 d. In contrast, treatments consisting of 70% CO2 (MAP4) and 100% CO2 (MAP5) limited increases in mean L. monocytogenes counts to
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effect of modified atmosphere packaging on the growth of Spoilage Microorganisms and listeria monocytogenes on fresh cheese
2018Co-Authors: Stephanie R B Brown, Emily C Forauer, Dennis J DamicoAbstract:Queso Fresco has a limited shelf life and has been shown to support the rapid growth of Listeria monocytogenes during refrigerated storage. In addition to improving quality and extending shelf life, modified atmosphere packaging (MAP) has been used to control the growth of pathogenic Microorganisms in foods. The objectives of this study were to determine the effects of MAP conditions on the survival and growth of Spoilage Microorganisms and L. monocytogenes during storage of Queso Fresco manufactured without starter cultures. For L. monocytogenes experiments, cheeses were surface inoculated at ∼4 log10 cfu/g before packaging. Inoculated and uninoculated (shelf life experiments) cheeses were placed in 75-µm high-barrier pouches, packaged under 1 of 7 conditions including air, vacuum, or combinations of N2 and CO2 [100% N2 (MAP1), 30% CO2:70% N2 (MAP2), 50% CO2:50% N2 (MAP3), or 70% CO2:30% N2 (MAP4), 100% CO2 (MAP5)], and stored at 7°C. Samples were removed weekly through 35 d of storage. Listeria monocytogenes counts were determined for inoculated samples. Uninoculated samples were assayed for mesophilic and psychrotolerant counts, lactic acid bacteria, coliforms, and yeast and mold. In general, cheeses packaged under conditions consisting of higher contents of CO2 had lower pH levels during storage compared with those stored in conditions with lower levels or no CO2 at all. Similarly, the antimicrobial efficacy of MAP in controlling Spoilage Microorganisms increased with increasing CO2 content, whereas conditions consisting of 100% N2, vacuum, or air were less effective. Mean L. monocytogenes counts remained near inoculation levels for all treatments at d 1 but increased ∼2 log10 cfu/g on cheeses packaged in air, vacuum, and 100% N2 (MAP1) conditions at d 7 and an additional ∼1.5 log10 cfu/g at d 14 where they remained through 35 d. In contrast, treatments consisting of 70% CO2 (MAP4) and 100% CO2 (MAP5) limited increases in mean L. monocytogenes counts to <1 log10 cfu/g through 14 d and ∼1.5 log10 cfu/g by d 21. Mean L. monocytogenes counts increased to levels significantly higher than inoculation (d 0) on cheeses stored in MAP2 and MAP3 on d 21, on d 28 for MAP4, and on d 35 for cheeses stored under MAP5 conditions. Overall, significant treatment × time interactions were observed between air, vacuum, and MAP1 when each was compared with MAP2, MAP3, MAP4, and MAP5. These data demonstrate that packaging fresh cheese under modified atmospheres containing CO2 may be a promising approach to extend shelf life while limiting L. monocytogenes growth during cold storage.
Stephanie R B Brown - One of the best experts on this subject based on the ideXlab platform.
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effect of modified atmosphere packaging on the growth of Spoilage Microorganisms and listeria monocytogenes on fresh cheese
2018Co-Authors: Stephanie R B Brown, Emily C Forauer, Dennis J DamicoAbstract:ABSTRACT Queso Fresco has a limited shelf life and has been shown to support the rapid growth of Listeria monocytogenes during refrigerated storage. In addition to improving quality and extending shelf life, modified atmosphere packaging (MAP) has been used to control the growth of pathogenic Microorganisms in foods. The objectives of this study were to determine the effects of MAP conditions on the survival and growth of Spoilage Microorganisms and L. monocytogenes during storage of Queso Fresco manufactured without starter cultures. For L. monocytogenes experiments, cheeses were surface inoculated at ∼4 log10 cfu/g before packaging. Inoculated and uninoculated (shelf life experiments) cheeses were placed in 75-µm high-barrier pouches, packaged under 1 of 7 conditions including air, vacuum, or combinations of N2 and CO2 [100% N2 (MAP1), 30% CO2:70% N2 (MAP2), 50% CO2:50% N2 (MAP3), or 70% CO2:30% N2 (MAP4), 100% CO2 (MAP5)], and stored at 7°C. Samples were removed weekly through 35 d of storage. Listeria monocytogenes counts were determined for inoculated samples. Uninoculated samples were assayed for mesophilic and psychrotolerant counts, lactic acid bacteria, coliforms, and yeast and mold. In general, cheeses packaged under conditions consisting of higher contents of CO2 had lower pH levels during storage compared with those stored in conditions with lower levels or no CO2 at all. Similarly, the antimicrobial efficacy of MAP in controlling Spoilage Microorganisms increased with increasing CO2 content, whereas conditions consisting of 100% N2, vacuum, or air were less effective. Mean L. monocytogenes counts remained near inoculation levels for all treatments at d 1 but increased ∼2 log10 cfu/g on cheeses packaged in air, vacuum, and 100% N2 (MAP1) conditions at d 7 and an additional ∼1.5 log10 cfu/g at d 14 where they remained through 35 d. In contrast, treatments consisting of 70% CO2 (MAP4) and 100% CO2 (MAP5) limited increases in mean L. monocytogenes counts to
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effect of modified atmosphere packaging on the growth of Spoilage Microorganisms and listeria monocytogenes on fresh cheese
2018Co-Authors: Stephanie R B Brown, Emily C Forauer, Dennis J DamicoAbstract:Queso Fresco has a limited shelf life and has been shown to support the rapid growth of Listeria monocytogenes during refrigerated storage. In addition to improving quality and extending shelf life, modified atmosphere packaging (MAP) has been used to control the growth of pathogenic Microorganisms in foods. The objectives of this study were to determine the effects of MAP conditions on the survival and growth of Spoilage Microorganisms and L. monocytogenes during storage of Queso Fresco manufactured without starter cultures. For L. monocytogenes experiments, cheeses were surface inoculated at ∼4 log10 cfu/g before packaging. Inoculated and uninoculated (shelf life experiments) cheeses were placed in 75-µm high-barrier pouches, packaged under 1 of 7 conditions including air, vacuum, or combinations of N2 and CO2 [100% N2 (MAP1), 30% CO2:70% N2 (MAP2), 50% CO2:50% N2 (MAP3), or 70% CO2:30% N2 (MAP4), 100% CO2 (MAP5)], and stored at 7°C. Samples were removed weekly through 35 d of storage. Listeria monocytogenes counts were determined for inoculated samples. Uninoculated samples were assayed for mesophilic and psychrotolerant counts, lactic acid bacteria, coliforms, and yeast and mold. In general, cheeses packaged under conditions consisting of higher contents of CO2 had lower pH levels during storage compared with those stored in conditions with lower levels or no CO2 at all. Similarly, the antimicrobial efficacy of MAP in controlling Spoilage Microorganisms increased with increasing CO2 content, whereas conditions consisting of 100% N2, vacuum, or air were less effective. Mean L. monocytogenes counts remained near inoculation levels for all treatments at d 1 but increased ∼2 log10 cfu/g on cheeses packaged in air, vacuum, and 100% N2 (MAP1) conditions at d 7 and an additional ∼1.5 log10 cfu/g at d 14 where they remained through 35 d. In contrast, treatments consisting of 70% CO2 (MAP4) and 100% CO2 (MAP5) limited increases in mean L. monocytogenes counts to <1 log10 cfu/g through 14 d and ∼1.5 log10 cfu/g by d 21. Mean L. monocytogenes counts increased to levels significantly higher than inoculation (d 0) on cheeses stored in MAP2 and MAP3 on d 21, on d 28 for MAP4, and on d 35 for cheeses stored under MAP5 conditions. Overall, significant treatment × time interactions were observed between air, vacuum, and MAP1 when each was compared with MAP2, MAP3, MAP4, and MAP5. These data demonstrate that packaging fresh cheese under modified atmospheres containing CO2 may be a promising approach to extend shelf life while limiting L. monocytogenes growth during cold storage.
S Tajchakavit - One of the best experts on this subject based on the ideXlab platform.
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enhanced destruction of Spoilage Microorganisms in apple juice during continuous flow microwave heating
1998Co-Authors: S Tajchakavit, Hosahalli S Ramaswamy, Patrick FustierAbstract:Abstract Destruction kinetics of two selected Spoilage Microorganisms, Saccharomyces cerevisiae and Lactobacillus plantarum in apple juice were evaluated under continuous flow microwave heating conditions and compared with conventional batch heating in a water bath. Inoculated apple juice was heated in a microwave oven (700 W, 2450 MHz) under continuous-flow conditions to selected exit temperatures (52.5–65°C). Aliquots of inoculated juice were also subjected to batch thermal treatments (50–80°C) in a well-stirred water bath. Time-temperature profiles obtained both during heating and cooling of test samples were used to correct both come-up and come-down times. The time-corrected D-values under microwave heating were 4.8, 2.1 and 1.1 s at 52.5, 55 and 57.5°C, respectively, for S. cerevisiae and 14, 3.8 and 0.79 s at 57.5, 60 and 62.5°C, respectively, for L. plantarum with corresponding z-values of 7 and 4.5°C. D-values under batch thermal heating were 58, 25, 10 and 1.9 s at 50, 55, 60 and 70°C, respectively, for S. cerevisiae and 52, 22, 8.4 and 1.2 s at 55, 60, 70 and 80°C, respectively, for L. plantarum with corresponding z-values of 13.4 and 15.9°C. Microbial destruction thus occurred much faster under microwave heating than under thermal heating suggesting some contributory enhanced effects to be associated with microwave heating.