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1.
Foods ; 13(3)2024 Feb 01.
Article de Anglais | MEDLINE | ID: mdl-38338599

RÉSUMÉ

Food additives are employed in the food industry to enhance the color, smell, and taste of foods, increase nutritional value, boost processing efficiency, and extend shelf life. Consumers are beginning to prioritize food ingredients that they perceive as supporting a healthy lifestyle, emphasizing ingredients they deem acceptable as alternative or "clean-label" ingredients. Ready-to-eat (RTE) meat products can be contaminated with pathogens and spoilage microorganisms after the cooking step, contributing to food spoilage losses and increasing the risk to consumers for foodborne illnesses. More recently, consumers have advocated for no artificial additives or preservatives, which has led to a search for antimicrobials that meet these demands but do not lessen the safety or quality of RTE meats. Lactates and diacetates are used almost universally to extend the shelf life of RTE meats by reducing spoilage organisms and preventing the outgrowth of the foodborne pathogen Listeria monocytogenes. These antimicrobials applied to RTE meats tend to be broad-spectrum in their activities, thus affecting overall microbial ecology. It is to the food processing industry's advantage to target spoilage organisms and pathogens specifically.

2.
Heliyon ; 9(9): e19574, 2023 Sep.
Article de Anglais | MEDLINE | ID: mdl-37809834

RÉSUMÉ

This review highlights the critical concern foreign material contamination poses across the food processing industry and provides information on methods and implementations to minimize the hazards caused by foreign materials. A foreign material is defined as any non-food, foreign bodies that may cause illness or injury to the consumer and are not typically part of the food. Foreign materials can enter the food processing plant as part of the raw materials such as fruit pits, bones, or contaminants like stones, insects, soil, grit, or pieces of harvesting equipment. Over the past 20 years, foreign materials have been responsible for about one out of ten recalls of foods, with plastic fragments being the most common complaint. The goal of this paper is to further the understanding of the risks foreign materials are to consumers and the tools that could be used to minimize the risk of foreign objects in foods.

3.
Microorganisms ; 11(9)2023 Aug 27.
Article de Anglais | MEDLINE | ID: mdl-37764008

RÉSUMÉ

Listeria continues to be a persistent foodborne pathogen that is responsible for human cases of listeriosis when contaminated food products are consumed. Human subjects considered to be most susceptible include the elderly, immunocompromised, and pregnant women. Listeria is characterized as a saprophytic organism with the capability of responding and adapting to constantly changing environments because it possesses multiple stress response mechanisms to overcome varying temperatures, salt concentrations, and pH, among others. Primary foods and food products associated with listeriosis include dairy products and ready-to-eat meats such as turkey products. Historically, chicken eggs have not been identified as a primary source of Listeria, but the potential for contamination during egg production and processing does exist. Listeria species have been isolated from egg-processing plant equipment and are presumed to occur in egg-processing plant environments. Whether Listeria is consistently disseminated onto eggs beyond the egg-processing plant is a risk factor that remains to be determined. However, research has been conducted over the years to develop egg wash solutions that generate combinations of pH and other properties that would be considered inhibitory to Listeria. Even less is known regarding the association of Listeria with alternative egg production systems, but Listeria has been isolated from pasture flock broilers, so it is conceivable, given the nature of the outdoor environments, that layer birds under these conditions would also be exposed to Listeria and their eggs become contaminated. This review focuses on the possibility of Listeria occurring in conventional and alternative egg-laying production and processing systems.

4.
Microorganisms ; 11(5)2023 May 16.
Article de Anglais | MEDLINE | ID: mdl-37317275

RÉSUMÉ

Listeria monocytogenes, an intra-cellular, Gram-positive, pathogenic bacterium, is one of the leading agents of foodborne illnesses. The morbidity of human listeriosis is low, but it has a high mortality rate of approximately 20% to 30%. L. monocytogenes is a psychotropic organism, making it a significant threat to ready-to-eat (RTE) meat product food safety. Listeria contamination is associated with the food processing environment or post-cooking cross-contamination events. The potential use of antimicrobials in packaging can reduce foodborne disease risk and spoilage. Novel antimicrobials can be advantageous for limiting Listeria and improving the shelf life of RTE meat. This review will discuss the Listeria occurrence in RTE meat products and potential natural antimicrobial additives for controlling Listeria.

5.
SN Soc Sci ; 2(9): 173, 2022.
Article de Anglais | MEDLINE | ID: mdl-36033639

RÉSUMÉ

The recent shift in the labor force that has occurred in many developed countries has been greater than any shift prior to 2020. This shift was caused by reduced birthrates coupled with the rising percentage of mature workers in the labor force, compounded by the 2020 global shut-down due to Covid-19. Managers and HR directors need to act now to gather the necessary data on their employees and their company's projected labor needs to accurately plan for their short- and long-term labor needs. A partial solution for this impending labor shortage is for companies to proactively become the "employer of choice" for their graying workforce by making necessary accommodations to retain and recruit mature workers. The concept of employer of choice relates to creating a work climate that attracts and retains workers to a specific employment opportunity. This article focuses on the steps that can be taken by employers to minimize the impact of this looming labor shortage on their company as well as on the overall economy. The article also provides background on some of the reasons why many mature workers want and need to continue working and the imperatives as to why immediate action on the part of employers is necessary.

6.
J Food Prot ; 85(5): 871-878, 2022 05.
Article de Anglais | MEDLINE | ID: mdl-35146514

RÉSUMÉ

Food processing environment flooring can become contaminated with pathogens in many ways including foot and equipment traffic, incoming materials, and floor drain backups.  Natural antimicrobial turmeric and commercially available powdered floor treatments may reduce the levels of pathogens on flooring thereby reducing the risk of cross contamination from the floor to food contact surfaces. These chemicals were evaluated to determine their effectiveness against cocktails of Salmonella , Escherichia coli , and Listeria monocytogenes dried onto the surfaces of carriers made from polyurethane-concrete commercial flooring material.  Aqueous test solutions were prepared from the minimum treatment required per m 2 from the manufacturer's instructions diluted in sterile water.  Potential synergy between turmeric and a percarbonate based commercial floor treatment was explored with a mixture of turmeric and sodium percarbonate, each at approximately 37g/m 2 application rate.  Each inoculated carrier was exposed to the treatment solutions or a sterile water control for 10 minutes at room temperature, neutralized with Hi-Cap neutralizing broth, the bacteria suspended, enumerated, and log 10 reductions calculated for each treatment and inoculum combination.  Mean log 10 CFU/carrier reductions with standard deviations ranged between 4.29±0.34 for the sodium percarbonate (SPC) based treatment and 0.004±0.23 for turmeric for Salmonella , 4.81±0.16 for SPC based treatment and -0.16±0.62 for turmeric for E. coli , and 4.88±0.6 for SPC based treatment and -0.16±0.15 for turmeric for L. monocytogenes .


Sujet(s)
Escherichia coli O157 , Listeria monocytogenes , Polyuréthanes/pharmacologie , Microbiologie alimentaire , Poudres , Numération de colonies microbiennes , Salmonella , Eau
7.
Foods ; 10(12)2021 Nov 23.
Article de Anglais | MEDLINE | ID: mdl-34945450

RÉSUMÉ

Rice supplies about 20% of the calories to the world's consumers. Milling removes the outer husk and bran, breaking about 20% of the rice kernels during the milling process that equates to almost 100,000,000 tons of rice annually. Broken rice is discounted in price by almost half or relegated to non-human consumption. This study seeks to understand why this large percentage of rice production is discounted for human consumption. Consumers who routinely consume rice evaluated raw and cooked rice with 5%, 10%, 20%, 30% and 40% levels of brokens. Sensory analysis indicated the appearance of raw rice with high levels of brokens affected the price consumers were willing to pay. Panelists were not able to discern sensory differences amongst cooked rice samples with different brokens percentages despite an eight-fold difference in brokens (p < 0.01). From this, we concluded that the price discounts imposed on broken rice are not because of perceived differences in the eating quality of cooked rice. Overall impression and overall texture were the two most significant determinants in willingness to purchase rice. The five cooked-rice samples with different levels of broken rice inclusion did not differ in terms of willingness to purchase.

8.
J Food Prot ; 80(10): 1749-1759, 2017 10.
Article de Anglais | MEDLINE | ID: mdl-28922027

RÉSUMÉ

The soilborne pathogen Listeria monocytogenes frequently contaminates food products and food processing environments and is able to survive desiccation, high osmotic pressures, and starvation. However, little is known about how this pathogen survives starvation at 4°C. This study provides evidence that L. monocytogenes is able to survive total nutrient starvation for 4 weeks. L. monocytogenes strains EGD-e, Scott A, F2365, and HCC23 were starved individually in sterile water. Colony counts declined over 4 weeks, with Scott A declining the most rapidly. Transmission electron microscopy images revealed degradation of starving cell membranes and altered cytosols. Starving cells were subjected to the metabolic inhibitors fluoride, arsenite, 2,4-dinitrophenol, iodoacetate, and cyanide individually. Iodoacetate, which inhibits glyceraldehyde-3-phosphate dehydrogenase, completely reduced cultivable counts below the level of detection compared with the control starving cells; 2,4-dinitrophenol, which dissipates proton motive force, almost completely reduced cultivable counts. These results suggest that L. monocytogenes strains EGD-e, Scott A, F2365, and HCC23 are actively using part of the glycolysis pathway while starving. These results suggest that starving L. monocytogenes cells retain aspects of active metabolism.


Sujet(s)
Basse température , Microbiologie alimentaire , Listeria monocytogenes/croissance et développement , Viabilité microbienne , Adaptation physiologique , Numération de colonies microbiennes , Manipulation des aliments , Stress physiologique
9.
J Food Prot ; 80(10): 1613-1622, 2017 10.
Article de Anglais | MEDLINE | ID: mdl-28853629

RÉSUMÉ

In 2000, the Consumer Goods Forum established the Global Food Safety Initiative (GFSI) to increase the safety of the world's food supply and to harmonize food safety regulations worldwide. In 2013, a university research team in conjunction with Diversey Consulting (Sealed Air), the Consumer Goods Forum, and officers of GFSI solicited input from more than 15,000 GFSI-certified food producers worldwide to determine whether GFSI certification had lived up to these expectations. A total of 828 usable questionnaires were analyzed, representing about 2,300 food manufacturing facilities and food suppliers in 21 countries, mainly across Western Europe, Australia, New Zealand, and North America. Nearly 90% of these certified suppliers perceived GFSI as being beneficial for addressing their food safety concerns, and respondents were eight times more likely to repeat the certification process knowing what it entailed. Nearly three-quarters (74%) of these food manufacturers would choose to go through the certification process again even if certification were not required by one of their current retail customers. Important drivers for becoming GFSI certified included continuing to do business with an existing customer, starting to do business with new customer, reducing the number of third-party food safety audits, and continuing improvement of their food safety program. Although 50% or fewer respondents stated that they saw actual increases in sales, customers, suppliers, or employees, significantly more companies agreed than disagreed that there was an increase in these key performance indicators in the year following GFSI certification. A majority of respondents (81%) agreed that there was a substantial investment in staff time since certification, and 50% agreed there was a significant capital investment. This survey is the largest and most representative of global food manufacturers conducted to date.


Sujet(s)
Manipulation des aliments/méthodes , Manipulation des aliments/statistiques et données numériques , Sécurité des aliments , Enquêtes et questionnaires , Australie , Sécurité des produits de consommation/normes , Europe , Humains , Nouvelle-Zélande , Amérique du Nord
10.
Front Vet Sci ; 4: 93, 2017.
Article de Anglais | MEDLINE | ID: mdl-28660201

RÉSUMÉ

In some animals, the typical body temperature can be higher than humans, for example, 42°C in poultry and 40°C in rabbits which can be a potential thermal stress challenge for pathogens. Even in animals with lower body temperatures, when infection occurs, the immune system may increase body temperature to reduce the chance of survival for pathogens. However, some pathogens can still easily overcome higher body temperatures and/or rise in body temperatures through expression of stress response mechanisms. Salmonella is the causative agent of one of the most prevalent foodborne illnesses, salmonellosis, and can readily survive over a wide range of temperatures due to the efficient expression of the heat (thermal) stress response. Therefore, thermal resistance mechanisms can provide cross protection against other stresses including the non-specific host defenses found within the human body thus increasing pathogenic potential. Understanding the molecular mechanisms associated with thermal responses in Salmonella is crucial in designing and developing more effective or new treatments for reducing and eliminating infection caused by Salmonella that have survived heat stress. In this review, Salmonella thermal resistance is assessed followed by an overview of the thermal stress responses with a focus on gene regulation by sigma factors, heat shock proteins, along with the corresponding thermosensors and their association with virulence expression including a focus on a potential link between heat resistance and potential for infection.

11.
Am J Infect Control ; 44(12): 1469-1474, 2016 12 01.
Article de Anglais | MEDLINE | ID: mdl-27908434

RÉSUMÉ

BACKGROUND: Handwashing (HW) compliance, although an effective means of limiting childhood illness, remains low among personnel in early childhood centers (ECCs). Our study determined HW compliance and efficacy of ECC personnel. METHODS: Surveillance cameras were used to determine HW opportunities, compliance, occurrences, and effectiveness based on child-care oriented criteria. RESULTS: We observed 349 HW triggering events, with 14 events per hour; a median of 2 personnel (caregivers, paraprofessional aides, or parents) were present at any given time period. Compliance was 30% (caregivers), 11% (paraprofessional aides), and 4% (parents), with an overall compliance of 22%. Between-room and between-age groups of children being cared for and compliance of caregivers and paraprofessional aides were not found to be significantly different (P < .05). For all personnel between the 10 different rooms, the median compliance was 20.2% (95% confidence interval, 8%-35%). Only 7% of personnel taking care of 2- to 3-year-old children washed their hands, the lowest compliance per age group. Of all steps in HW, paper towel usage had the highest compliance, with a 97% adherence, whereas turning off the faucet with a paper towel was the lowest at 17%. CONCLUSIONS: Methods and strategies need to be developed to increase compliance. Current technology provides an effective means of gathering data for determining HW compliance in ECCs.


Sujet(s)
Soins de l'enfant , Adhésion aux directives/statistiques et données numériques , Désinfection des mains/méthodes , Établissements de santé , Enfant d'âge préscolaire , Femelle , Humains , Nourrisson , Mâle
12.
Food Sci Biotechnol ; 25(6): 1619-1625, 2016.
Article de Anglais | MEDLINE | ID: mdl-30263453

RÉSUMÉ

This study aimed to determine individual and combined effects of smoking and marination on the sensory characteristics of boneless, skinless chicken breast meat. Four types of cooked, cold-cut chicken breast meat, i.e., marinated cooked, marinated smoked, and controls of non-marinated cooked and non-marinated smoked chicken, were evaluated for 28 sensory characteristics. Marination significantly increased saltiness, sweetness, roasted flavor, smoked flavor, and moistness of the cold-cut chicken breast meat. In addition, smoking significantly enhanced the saltiness, bitterness, roasted flavor, smoked flavor, and moistness of mass. Interestingly, a combination of smoking and marination processes resulted in a synergistic increase in the perceived moistness of mass compared to their individual treatments. In conclusion, this study demonstrates individual and combined influences of smoking and marination on the sensory characteristics of cold-cut chicken breast meat.

13.
Front Vet Sci ; 2: 35, 2015.
Article de Anglais | MEDLINE | ID: mdl-26664964

RÉSUMÉ

The antimicrobial activity of essential oils and their components has been recognized for several years. Essential oils are produced as secondary metabolites by many plants and can be distilled from all different portions of plants. The recent emergence of bacteria resistant to multiple antibiotics has spurred research into the use of essential oils as alternatives. Recent research has demonstrated that many of these essential oils have beneficial effects for livestock, including reduction of foodborne pathogens in these animals. Numerous studies have been made into the mode of action of essential oils, and the resulting elucidation of bacterial cell targets has contributed to new perspectives on countering antimicrobial resistance and pathogenicity of these bacteria. In this review, an overview of the current knowledge about the antibacterial mode of action of essential oils and their constituents is provided.

14.
J Food Sci ; 80(7): M1557-62, 2015 Jul.
Article de Anglais | MEDLINE | ID: mdl-26033521

RÉSUMÉ

UNLABELLED: Ready-to-eat luncheon meats sliced in retail delis have been found to pose the greatest risk of foodborne illness from Listeria monocytogenes among all ready-to-eat foods. Slicers used in delis have many removable parts that are connected with seals and gaskets, with spaces, cracks and crevices that are difficult to clean adequately and may provide a niche for L. monocytogenes survival. Standard cleaning and sanitizing practices used by deli employees may not eliminate Listeria in these niches. Moist heat is known to be more effective against L. monocytogenes than dry heat at the same temperature and time. The study reported here investigated the effects of moist heat combined with quaternary ammonium compounds (5 or 10 ppm), chlorine (10 or 25 ppm) or peracetic acid (10 or 25 ppm) on inactivating L. monocytogenes attached to stainless steel or aluminum coupons cut from commercial deli meat slicer components. All sanitizers when used alone resulted in a 2- to 3-log reduction of L. monocytogenes on stainless steel or aluminum surfaces, while moist heat alone resulted in a 3- to 4-log reduction. When combined with heat the quaternary ammonium was used at 5 ppm, peracetic acid at 10 ppm and chlorine at 10 ppm. When the 2 lethal treatments were combined there was a 5- to7-log reduction as compared to initial inoculation. PRACTICAL APPLICATION: The results of this study will provide a better understanding and potential methods for the sanitization of industrial deli meat slicers. In turn, the knowledge gained from this study can reduce the risk of contamination and outbreaks of L. monocytogenes and other food-borne pathogens for consumers.


Sujet(s)
Aluminium , Contamination de matériel/prévention et contrôle , Listeria monocytogenes/croissance et développement , Amélioration du niveau sanitaire , Acier inoxydable , Chlore/pharmacologie , Numération de colonies microbiennes , Contamination des aliments/prévention et contrôle , Microbiologie alimentaire , Maladies d'origine alimentaire/microbiologie , Maladies d'origine alimentaire/prévention et contrôle , Température élevée , Listeria monocytogenes/isolement et purification , Produits carnés/microbiologie , Viabilité microbienne/effets des médicaments et des substances chimiques , Acide peracétique/pharmacologie , Facteurs de risque
15.
Pharmacogn Rev ; 9(17): 1-11, 2015.
Article de Anglais | MEDLINE | ID: mdl-26009686

RÉSUMÉ

Sweetgum trees are large, deciduous trees found in Asia and North America. Sweetgum trees are important resources for medicinal and other beneficial compounds. Many of the medicinal properties of sweetgum are derived from the resinous sap that exudes when the outer bark of the tree has been damaged. The sap, known as storax, has been used for centuries to treat common ailments such as skin problems, coughs, and ulcers. More recently, storax has proven to be a strong antimicrobial agent even against multidrug resistant bacteria such as methicillin-resistant Staphylococcus aureus. In addition to the sap, the leaves, bark, and seeds of sweetgum also possess beneficial compounds such as shikimic acid, a precursor to the production of oseltamivir phosphate, the active ingredient in Tamiflu®-an antiviral drug effective against several influenza viruses. Other extracts derived from sweetgum trees have shown potential as antioxidants, anti-inflammatory agents, and chemopreventive agents. The compounds found in the extracts derived from sweetgum sap suppress hypertension in mice. Extracts from sweetgum seeds have anticonvulsant effects, which may make them suitable in the treatment of epilepsy. In addition to the potential medicinal uses of sweetgum extracts, the extracts of the sap possess antifungal activity against various phytopathogenic fungi and have been effective treatments for reducing nematodes and the yellow mosquito, Aedes aegypti, populations thus highlighting the potential of these extracts as environment-friendly pesticides and antifungal agents. The list of value-added products derived from sweetgum trees can be increased by continued research of this abundantly occurring tree.

16.
Meat Sci ; 102: 41-8, 2015 Apr.
Article de Anglais | MEDLINE | ID: mdl-25529288

RÉSUMÉ

Dried plums (prunes) have been marketed to consumers for consumption directly from the package as a convenient snack and have been reported to have broad health benefits. Only recently have fractionated, dried plum ingredients been investigated for their functionality in food and feed products. Dried plum puree, dried plum fiber, dried plum powder, dried plum concentrate, and fresh plum concentrate have been investigated to date. They have been evaluated as fat replacers in baked goods, antioxidants in meat formulations, phosphate replacers in chicken marinades, and antimicrobials in food systems. Overall, dried plum products have been shown to be effective at reducing lipid oxidation and show promise as antimicrobials.


Sujet(s)
Qualité alimentaire , Conserves et aliments avec conservateur/analyse , Fruit/composition chimique , Aliment fonctionnel/analyse , Produits carnés/analyse , Prunus/composition chimique , Anti-infectieux/composition chimique , Antioxydants/composition chimique , Condiments/analyse , Cuisine (activité) , Substituts de matières grasses/composition chimique , Aromatisants/composition chimique , Manipulation des aliments , Conservateurs alimentaires/composition chimique
17.
J Food Prot ; 77(6): 934-40, 2014 Jun.
Article de Anglais | MEDLINE | ID: mdl-24853515

RÉSUMÉ

Condensed smoke or liquid smoke (LS) and lauric arginate (LAE) are antimicrobials used in food preservation. They have demonstrated abilities to reduce or inhibit pathogenic and spoilage organisms. Few studies, however, have reported on the effectiveness of LS or LAE over the range of temperatures typically encountered in food marketing channels. Therefore, the effects of temperature on the antimicrobial properties of two commercial LS fractions, an LS derived from pecan shells, and LAE against two common foodborne pathogens, Listeria and Salmonella, were investigated. The MICs of the three LS samples and LAE were measured at 4, 10, and 37°C for Listeria monocytogenes strains 2045 (Scott A, serotype 4b) and 10403S (serotype 1/2a) and two strains of Listeria innocua, a well-established surrogate, and at 10, 25, and 37°C for Salmonella enterica serovar Typhimurium and Salmonella enterica serovar Heidelberg. The MICs for LS against Listeria ranged from 3 to 48% (vol/vol), with higher MICs seen with lower temperatures. The MICs for LS on Salmonella ranged from 3 to 24%. Values for LAE ranged between 0.004 and 0.07% for both pathogens, and like LS, higher MICs were always associated with lower incubation temperatures. Understanding how storage temperature affects the efficacy of antimicrobials is an important factor that can contribute to lowering the hurdles of use levels and costs of antimicrobials and ultimately improve food safety for the consumer.


Sujet(s)
Antibactériens/pharmacologie , Arginine/analogues et dérivés , Carya/composition chimique , Conservation aliments/méthodes , Listeria monocytogenes/effets des médicaments et des substances chimiques , Salmonella enterica/effets des médicaments et des substances chimiques , Fumée/analyse , Arginine/pharmacologie , Microbiologie alimentaire , Conservation aliments/instrumentation , Tests de sensibilité microbienne , Graines/composition chimique , Température
18.
Meat Sci ; 97(2): 197-206, 2014 Jun.
Article de Anglais | MEDLINE | ID: mdl-24583328

RÉSUMÉ

The smoking of foods, especially meats, has been used as a preservation technique for centuries. Today, smoking methods often involve the use of wood smoke condensates, commonly known as liquid smoke. Liquid smoke is produced by condensing wood smoke created by the pyrolysis of sawdust or wood chips followed by removal of the carcinogenic polyaromatic hydrocarbons. The main products of wood pyrolysis are phenols, carbonyls and organic acids which are responsible for the flavor, color and antimicrobial properties of liquid smoke. Several common food-borne pathogens such as Listeria monocytogenes, Salmonella, pathogenic Escherichia coli and Staphylococcus have shown sensitivity to liquid smoke in vitro and in food systems. Therefore liquid smoke has potential for use as an all-natural antimicrobial in commercial applications where smoke flavor is desired. This review will cover the application and effectiveness of liquid smoke and fractions of liquid smoke as an all-natural food preservative. This review will be valuable for the industrial and research communities in the food science and technology areas.


Sujet(s)
Antibactériens/pharmacologie , Bactéries/effets des médicaments et des substances chimiques , Aromatisants , Conservation aliments/méthodes , Conservateurs alimentaires/pharmacologie , Viande/microbiologie , Fumée , Animaux , Manipulation des aliments , Microbiologie alimentaire , Humains , Bois
19.
J Environ Sci Health B ; 49(4): 290-8, 2014.
Article de Anglais | MEDLINE | ID: mdl-24502216

RÉSUMÉ

Methionine is the first limiting amino acid in poultry feed. Currently, methionine supplement is synthesized from an expensive chemical process requiring hazardous chemicals. Therefore, the objectives of this study were isolation of methionine producing bacteria from environmental samples and quantification of methionine production in these isolated bacteria. MCGC medium was selected as the isolation medium for methionine-producing bacteria by using Corynebacterium glutamicum ATCC13032 and Escherichia coli ATCC23798 as the positive and negative controls, respectively. Thirty-nine bacterial strains were obtained from environmental samples. Only strains A121, A122, A151 and A181 were able to tolerate up to 0.1% (w/v) of ethionine or norleucine. These isolated strains were identified by sequencing small subunit rRNA genes. The results revealed that bacterial strains A121, A122, A151and A181 were Klebsiella species, Acinetobacter baumannii, A. baumannii and Pseudomonas aeruginosa, respectively. When methionine production in strains A121 and A181 was quantitated, strains A121 and A181 generated methionine up to 31.1 and 124.6 µg/ml, respectively.


Sujet(s)
Bactéries/isolement et purification , Bactéries/métabolisme , Milieux de culture/métabolisme , Microbiologie de l'environnement , Méthionine/biosynthèse , Bactéries/génétique , Bactéries/croissance et développement , Milieux de culture/composition chimique , Méthionine/analogues et dérivés
20.
J Food Sci ; 78(12): M1899-903, 2013 Dec.
Article de Anglais | MEDLINE | ID: mdl-24279287

RÉSUMÉ

Growers and processors of USDA certified organic foods are in need of suitable organic antimicrobials. The purpose of the research reported here was to develop and test natural antimicrobials derived from an all-natural by-product, organic pecan shells. Unroasted and roasted organic pecan shells were subjected to solvent free extraction to produce antimicrobials that were tested against Listeria spp. and L. monocytogenes serotypes to determine the minimum inhibitory concentrations (MIC) of antimicrobials. The effectiveness of pecan shell extracts were further tested using a poultry skin model system and the growth inhibition of the Listeria cells adhered onto the skin model were quantified. The solvent free extracts of pecan shells inhibited Listeria strains at MICs as low as 0.38%. The antimicrobial effectiveness tests on a poultry skin model exhibited nearly a 2 log reduction of the inoculated cocktail mix of Listeria strains when extracts of pecan shell powder were used. The extracts also produced greater than a 4 log reduction of the indigenous spoilage bacteria on the chicken skin. Thus, the pecan shell extracts may prove to be very effective alternative antimicrobials against food pathogens and supplement the demand for effective natural antimicrobials for use in organic meat processing.


Sujet(s)
Anti-infectieux/isolement et purification , Carya/composition chimique , Nourriture biologique/analyse , Listeria/effets des médicaments et des substances chimiques , Viande/microbiologie , Noix/composition chimique , Animaux , Anti-infectieux/pharmacologie , Poulets , Numération de colonies microbiennes , Contamination des aliments/prévention et contrôle , Manipulation des aliments , Microbiologie alimentaire , Tests de sensibilité microbienne
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