Search results for "Food Preservatives"
showing 9 items of 29 documents
Effects of chitosan films on the growth of Listeria monocytogenes, Staphylococcus aureus and Salmonella spp. in laboratory media and in fish soup.
2009
The objective of this study was to assess the antimicrobial effectiveness of chitosonium acetate films on the growth of Listeria monocytogenes, Salmonella spp. and Staphylococcus aureus. The samples were tested in both laboratory conditions using Tryptone Soy Broth (TSB) and in a real food system using fish soup. The study was carried out at different temperatures (4, 12, and 37 degrees C) in order to discern the influence of such variables. Moreover, a sensory evaluation of the final product was performed as a parameter of consumer acceptance. The results showed a significant reduction of the bacterial growth, which greatly depended on the bacteria type, the temperature of incubation and t…
Assessment of the microbiological quality and wash treatments of lettuce served in University restaurants
2000
Abstract One hundred and forty-four samples of lettuce from 16 University restaurants were analyzed. The mesophilic aerobic counts of all samples ranged from 3.01 to 7.81 log 10 CFU g −1 . Results of total coliforms ranged from 3.38 log 10 most probable number (MPN) g −1 . Of the lettuce samples, 25.7% harbored Escherichia coli , 22.9% Staphylococcus aureus and 84% group D streptococci. Similarly, 10.4% of the samples harbored Aeromonas hydrophila , 2.8% Pseudomonas aeruginosa , and coliforms such as 14.6% Citrobacter freundii , 8.3% Klebsiella pneumoniae , 4.2% Enterobacter cloacae and 1.4% Providencia spp. Salmonella , Shigella and E. coli O157:H7 were not detected. When sodium hypochlori…
Characterization of antimicrobial properties on the growth of S. aureus of novel renewable blends of gliadins and chitosan of interest in food packag…
2007
The biocide properties of chitosan-based materials have been known for many years. However, typical antimicrobial formulations of chitosan, mostly chitosonium salts, are known to be very water sensitive materials which may impair their use in many application fields such as food packaging or food coating applications. This first work reports on the development and characterization of the antimicrobial properties of novel fully renewable blends of chitosan with more water-resistant gliadin proteins isolated from wheat gluten. Chitosan release to the nutrient broth from a wide range of blends was studied making use of the ninhydrin method. The results indicated that both pure chitosan and its…
Origanum vulgare subsp. hirtum Essential Oil Prevented Biofilm formation and showed antibacterial activity against planktonic and sessile bacterial c…
2013
Essential oils from six different populations of Origanum vulgare subsp. hirtum were compared for their antibiofilm properties. The six essential oils (A to F) were characterized by a combination of gas chromatography with flame ionization detector and gas chromatography with mass spectrometer detector analyses. All oils showed weak activity against the planktonic form of a group of Staphylococcus aureus strains and against a Pseudomonas aeruginosa ATCC 15442 reference strain. The ability to inhibit biofilm formation was investigated at sub-MIC levels of 200, 100, and 50 m g/ml by staining sessile cells with safranin. Sample E showed the highest average effectiveness against all tested stra…
Photoactivated chlorophyllin-based gelatin films and coatings to prevent microbial contamination of food products
2008
[EN] The aim of this work was to develop antimicrobial photosensitizer-containing edible films and coatings based on gelatin as the polymer matrix. incorporating sodium magnesium chlorophyllin (E-140) and sodium copper chlorophyllin (E-141). Chlorophyllins were incorporated into the gelatin film-forming solution and the inhibiting effect of the cast films was tested against Staphylococcus aureus and Listeria monocytogenes. The results demonstrated that water soluble sodium magnesium chlorophyllin and water soluble sodium copper chlorophyllin reduced the growth of S. aureus and L monocytogenes by 5 log and 4 log respectively. Subsequently, the activity of self-standing films and coatings con…
Inactivation of conidia of Penicillium chrysogenum, P. digitatum and P. italicum by ethanol solutions and vapours
2008
A fractional factorial design, 2(5-1) experiments, was used for assessing the influence of 5 factors: water activity, aw [0.7, 0.9], temperature, T ( degrees C) [10, 30], mode of application, A [liquid, vapour], ethanol concentration, E (% w/w) [5, 10] and time, t (d) [1, 4] on the inactivation of spores of Penicillium chrysogenum, P. digitatum and P. italicum. Survival was determined by germination at optimal conditions within 3d. The experimental response was log (N 0/Nt), where N 0 and Nt (spore ml(-1)) the concentrations of viable spores at t=0 and t respectively. By a decreasing order of sensitivity to ethanol, moulds were ranked as followed: P. digitatum, P. italicum and P. chrysogenu…
Application of seaweeds to develop new food products with enhanced shelf-life, quality and health-related beneficial properties
2017
International audience; Edible seaweeds are a good source of antioxidants, dietary fibers, essential amino acids, vitamins, phytochemicals, polyunsaturated fatty acids, and minerals. Many studies have evaluated the gelling, thickening and therapeutic properties of seaweeds when they are used individually. This review gives an overview on the nutritional, textural, sensorial, and health-related properties of food products enriched with seaweeds and seaweed extracts. The effect of seaweed incorporation on properties of meat, fish, bakery, and other food products were highlighted in depth. Moreover, the positive effects of foods enriched with seaweeds and seaweed extracts on different lifestyl…
Encapsulated Limonene: A Pleasant Lemon-Like Aroma with Promising Application in the Agri-Food Industry. A Review
2020
International audience; Limonene, mainly found as a major component in Citrus spp., has been proven to possess a valuable potential as sustainable replacement to synthetic pesticides and food preservatives. This review intends to give a clear overview of the principal emerging applications of limonene in the agri-food industry as antimicrobial, herbicidal and antioxidant agent. To successfully use limonene in a greener agri-food industry, its preservation had become a top concern for manufacturers. In order to elucidate the most efficient and sustainable manner to encapsulate limonene, the different techniques and materials tested up to the present are also reviewed. In general, encapsulati…
Application of bacteriocins in vegetable food biopreservation.
2007
Bacteriocins are generally recognized as "natural" compounds able to influence the safety and quality of foods. In the past years, a lot of works have been aimed to the detection, purification and characterisation of bacteriocins, as well as to their use in food preservation strategies. A list of review articles dealing with the application of bacteriocins to the protection of foods of animal origin is also available in literature, but it lacks for a summary on the utilization of bacteriocins in vegetable foods. These biopreservatives can be used in a number of ways in food systems and this paper mainly focuses on the state-of-the-art application of bacteriocins from lactic acid bacteria (L…