EFFECTS OF OZONE WASH FOR INACTIVATION OF S. TYPHIMURIUM AND BACKGROUND MICROBIOTA ON LETTUCE AND PARSLEY

WOS: 000325970500006Experiments were done with ozonated water to evaluate its efficacy in reducing the numbers of Salmonella Typhimurium and total mesophilic aerobic bacteria (TMAB) on vegetables and in improving their storage quality. Ozonated water (0.5, 1.0 and 1.5ppm) treatment for 3, 5 and 10min caused reductions in the number of TMAB of lettuce and parsley samples ranging between 0.48-1.25 and 0.40-1.03log units, respectively. The counts of S.Typhimurium on inoculated lettuce samples were reduced by ozonated water in the range of 1.14-3.06 log units reductions, while 0.28-2.57 log units reductions were achieved for parsley samples. On the other hand, the effect of tap water in reducing TMAB and S.Typhimurium counts was found ranging between 0.10-1.20 and 0.44-0.60 log units, respectively. Reduction capacity of ozonated water (1.5ppm/5min) on microbial population was also tested in a school kitchen and results were similar with the laboratory findings (P>0.05). To determine the effects of ozonated water on the storage quality of the samples, TMAB and mold-yeast counts of vegetables were investigated during the storage period at 4C for 15 days. Results of the study showed that ozonated water is mainly useful for reducing S.Typhimurium cells from vegetables. Practical ApplicationsConventional ozone generators, which needs compressors, air dryers, oxygen concentrators and ozone injectors, are too bulky to be used, in point-of-installations. On the other hand, in ozo-pen system, technology developed in recent years, ozone can be produced directly from the water to be treated itself instead of producing ozone from a dry air or dry oxygen gas source, and the system only needs handheld ozone generator, portable container and water. This study showed that ozonated water, which can be produced practically by ozone probes in a small scale and also at household levels, is a good alternative for improving microbiological quality of fresh produce.Ege University, Research FoundationEge UniversityThe financial support of Ege University, Research Foundation is gratefully acknowledged

Antimicrobial effect of koruk (unripe grape-Vitis vinifera) juice against. Salmonella typhimurium on salad vegetables

WOS: 000244153400015To evaluate the antimicrobial activity of koruk (unripe grape-Vitis vinifera) juice, cucumber and parsley samples were inoculated with two Salmonella typhimurium strains namely S. (typhimurium NRRL-B-4420 and S. typhimurium CCM 583 at the level of approximately 106 cfu/ml. The samples were treated with koruk juices produced by different methods (by using mortar and electrical blender) for 0, 15, 30 and 60 min. Salmonella cells were counted by using direct surface plating (on Tryptone Soya Agar, Bismuth Sulphite Agar or Xylose Desoxylate Agar with 50ppm, nalidixic acid;, TSAN, BSAN or XLDN) and overlay plating (on TSAN/BSAN) methods. Counts on TSAN/BSAN or TSAN, BSAN and XLDAN were not significantly different (P > 0.05). So, further experiments were done with direct surface plating on TSAN and BSAN. Overall statistical analysis indicated that, the antimicrobial effect of koruk juice was found to be dependent on the culture strains and products used (P 0.05) whereas reduction obtained at 0 time differed significantly (P < 0.05). On the other hand, no significant differences were found between the antimicrobial effects of koruk juices prepared by different methods. Results of the study showed that koruk juice used as flavouring and acidifying agent in Turkish kitchens, may be considered to be an alternative potential antimicrobial agent at household level for salad vegetables. (c) 2006 Elsevier Ltd. All rights reserved

Importance of acetic acid bacteria in food industry

WOS: 000286856200001Acetic acid bacteria (AAB) comprise a group of gram-negative or gram-variable, ellipsoidal to rod-shaped cells that have an obligate aerobic metabolism with oxygen as the terminal electron acceptor. In the first classification of AAB, two main genera were determined as Acetobacter and Gluconobacter, but nowadays twelve genera are recognized and accommodated to the family Acetobacteraceae, the Alphaproteobacteria: Acetobacter, Gluconobacter, Acidomonas, Gluconacetobacter, Asaia, Kozakia, Swaminathania, Saccharibacter, Neoasaia, Granulibacter, Tanticharoenia and Ameyamaea. Isolation, purification, identification and preservation of AAB are very difficult. Phenotypic methods based on physiological abilitiesies have been used for identification of AAB by using various media. These phenotypic properties have now been complemented or replaced by molecular techniques, which are DNA and RNA based techniques. AAB are widespread in nature on various plants (fruits, cereals, herbs, etc.). They are important microorganisms in food industry because of their ability to oxidize many types of sugars and alcohols to organic acids as end products during fermentation process. The best known industrial application of AAB is vinegar production. This group of bacteria is also used in cellulose and sorbose production. On the other hand, the oxidizing ability of AAB could have spoilage effect in some products such as in wine. The aim of the present review is to introduce the importance of AAB in food industry by showing their current taxonomy, enumeration, isolation and identification methods, isolation sources and beneficial effects in food production systems. (C) 2010 Elsevier Ltd. All rights reserved

Inactivation effect of marination liquids prepared with koruk juice and dried koruk pomace on Salmonella Typhimurium, Escherichia coli O157:H7 and Listeria monocytogenes inoculated on meat

WOS: 000474321400004PubMed ID: 31152975The aim of this study was to determine the effects of marination liquids prepared with koruk juice and dried koruk pomace in terms of meat safety. In the study, marination liquids containing two different concentrations of koruk juice (25% and 50%) or dried koruk pomace (1% and 2%) were prepared separately with or without ingredients (1% salt and 0.1% thyme). Meat samples inoculated with two different levels (congruent to 3 log and congruent to 6 log) of food-borne pathogens (S. Typhimurium, E. coli O157:H7 and L. monocytogenes) were marinated at 4 degrees C for different times (2, 24 and 48 h) and the effects of the treatment on target pathogens were determined. As a result of marinating process, the counts of S. Typhimurium, E. coli O157:H7 and L. monocytogenes inoculated at high levels log) on meat samples were reduced in the range of 0.109-2.648 log CFU/g, 0.264-3.373 log CFU/g and 0.023-2.781 log CFU/g, respectively. The most effective treatment in reducing the counts of S. Typhimurium and E. coli O157:H7 was achieved by marination with ML1 (50% koruk juice + 50% water) for 48 h, while marination with ML2 (50% koruk juice + 50% water + 1% salt + 0.1% thyme) for 24 h was the most effective treatment for L. monocytogenes. When low inoculum levels were used log), the counts of pathogens on meat samples were determined under detection limits after marination even for 2 h application. The results of sensory evaluation showed that the sample marinated with ML2 for 48 h was the most favored sample in terms of appearance, color, texture, taste and overall appreciation.Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [1170937]The authors are grateful for the financial support provided for the project entitled "Usage of Koruk Products (Koruk Juice and Dried Koruk Pomace) in Meat Technology for Increasing Product Safety and Developing Healthy Product Formulation" under project no: 1170937 by the Scientific and Technological Research Council of Turkey (TUBITAK)

Traditional Non-Dairy Fermented Products: A Candidate for Probiotics

Consumers are increasingly interested in foods that offer a well-balanced dietary profile as well as metabolic, physiological, and functional benefits. Dairy fermented products are widely consumed since they provide health benefits via probiotics. However, lactose intolerance, cholesterol content, allergic milk proteins are limiting factors for the consumption of dairy-derived probiotic foods. This problem has led to the exploration of non-dairy fermented probiotic foods derived from cereals, fruits, vegetables and plants. They represent a promising carrier for probiotic microorganisms. In this paper, chemical, microbiological and biological features of traditional non-dairy fermented foods were reviewed, especially by focusing on their probiotic potential

Microbiological quality of Tarhana, Turkish cereal based fermented food

WOS: 000299820500004Objectives Tarhana is a traditional fermented product produced from a mixture of yogurt and wheat flour in Turkey. The aim of the present study was to investigate the microbiological quality of tarhana and its raw material. Methods Samples were collected from eight different regions of Turkey during fermentation period and after drying process. Aerobic plate count, Staphylococcus aureus, Salmonella spp., Clostridium perfringens, coliform, Escherichia coli and Bacillus cereus analysis were applied for detecting the microbiological quality of tarhana samples. Results E. coli and S. aureus were not isolated from all the production steps used. Some of the tarhana samples were found containing coliform, Salmonella, C. perfringens and B. cereus at the beginning of the fermentation process; however, they were not isolated from other stages, except one dried tarhana sample, which were containing C. perfringens in low levels. It is found that yogurt and wheat flour samples met the microbiological criteria given for these products. Changes of pH and acidic values during tarhana fermentations were also detected in the study. Conclusion The results indicated that microbiological and chemical properties of tarhana change depending on the raw materials, fermentation time and techniques used in its production

Potential of Ozonated Water at Different Temperatures to Improve Safety and Shelf-Life of Fresh Cut Lettuce

WOS: 000430097400008The present study was carried out to determine the effect of ozonated water (2mg L-1) at different temperatures (4 degrees C and 15 degrees C) on the microbiological, color and sensory properties of lettuce. Cold ozone treatment (4 degrees C) significantly reduced the natural background microflora of lettuce. Salmonella Typhimurium and Escherichia coli inoculated on lettuce samples were insignificantly influenced by the temperature of water. During storage period at +4 degrees C for 14days, the highest quality was observed from the samples treated with cold ozonated water. Ozone treatments did not affect the color properties and sensory quality of lettuce samples.Ege University Research FoundationEge University [13-MUH-060]This work was financially supported by Ege University Research Foundation (Grant number 13-MUH-060)

Marination liquids enriched with probiotics and their inactivation effects against food-borne pathogens inoculated on meat

The aim of the study was to develop marination liquids (MLs) enriched with probiotics (Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus rhamnosus or their combination) to improve the safety and sensory quality of meat during marination. The total acidity, total phenolic content, antioxidant and antimicrobial activities of MLs were in the range of 0.70-0.92 g tartaric acid/100 mL, 331.00-513.80 mg GAE/L, 71.10%-93.37% and 6.50-10.00 mm, respectively. At the end of the marination, the numbers of Escherichia coli O157: H7, Listeria monocytogenes and Salmonella Typhimurium on meat samples ( approximately equal to 6 log CFU/g) were decreased in the range of 0.7-2.7, 2.1-3.3 and 0.8-2.0 log CFU/g, respectively, depending on the type of ML and the treatment time used. Additionally, meat sample marinated with MLs containing L. casei was the most preferred sample in terms of appearance, color, flavor and general acceptability. These results showed that the existing effects of koruk juice were increased by probiotics

Acid Tolerance of Lactic Acid Bacteria Isolated from Various Fermented Vegetables

WOS: 000521110200099[No abstract available