Effects of microwave assisted hydrodistillation (MAHD) and conventional hydrodistillation (HD) methods on yield, composition, specific gravity, refractive index, and antioxidant and antimicrobial activities of essential oil of Rosmarinus officinalis L were studied. The main aroma compounds of rosemary essential oil were found as 1,8-cineole and camphor. Trolox equivalent antioxidant capacity (TEAC) values for essential oils extracted by MAHD and HD were 1.52 mM/ml oil and 1.95 mM/ml oil, respectively. DPPH radical scavenging activity of the oils obtained by MAHD and HD were found as 60.55% and 51.04% respectively. Inhibitory effects of essential oils obtained by two methods on linoleic acid peroxidation were almost the same. Essential oils obtained by two methods inhibited growth of Esherichia coli O157:H7, Salmonella typhimurium NRRLE 4463 and Listeria monocytogenes Scott A with the same degree. However, inhibitory activity of essential oil obtained by MAHD on Staphylococcus aureus 6538P was stronger than that of obtained by HD (p<0.05).

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In this study, antioxidant and antimicrobial activities of essential oils obtained from oregano (Origanum vulgare ssp. hirtum) were determined by using solvent-free microwave extraction (SFME), supercritical fluid extraction, and conventional hydrodistillation (CH) methods. The inhibitory effects on the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical of essential oils obtained from oregano by using SFME and CH were similar. However, essential oil extracted by CH showed greater (2.69 μmol/μL of oil) Trolox equivalent antioxidant capacity (TEAC) than oregano oils obtained by SFME (P < .05). The difference between percentage inhibition and TEAC values most probably is due to the fact that undiluted and diluted samples are used in the percentage inhibition assay and the TEAC assay, respectively. TEAC values of oregano essential oils obtained by SFME at different microwave power levels were found to be similar and ranged from 0.72 to 0.84 μmol/μL of oil. Essential oils obtained by CH and SFME at different microwave powers inhibited the survival of Listeria monocytogenes, Salmonella typhimurium, and Escherichia coli O157:H7, whereas survival of Staphylococcus aureus was not influenced. In addition, oregano oil obtained by SFME at 40% power level did not show any inhibitory effect on E. coli O157:H7.

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In this research, the growth and survival of <i>E. coli</i> O157:H7, <i>Salmonella typhimurium</i> and <i>Staphylococcus aureus</i> were investigated during kefir fermentation. Two different levels of inoculation of the strains were conducted; the levels of 102 CFU/ml (EC-1, SA-1 and S-1) and 103 CFU/ml (EC-2, SA-2 and S-2). At 0, 2, 6, 12, and 24 hours of kefir fermentation at 23 ± 1°C, samples were taken and the counts of <i>E. coli</i> O157:H7, <i>S. typhimurium</i>, and <i>S. aureus</i> were determined. EC-1 grew from 2.29 ± 0.02 log CFU/ml to 4.13 ± 0.18 log CFU/ml whereas EC-2 grew from 3.22 ± 0.04 log CFU/ml to 6.78 ± 0.99 log CFU/ml. Both S-1 and S-2 viable populations grew during the fermentation period, where sample S-1 grew from 2.37 ± 0.20 log CFU/ml to 4.64 ± 0.67 log CFU/ml and sample S-2 grew from 3.52 ± 0.07 log CFU/ml to 5.60 ± 0.10 log CFU/ml. SA-2 strains grew from 3.06 log CFU/ml to 3.64 log CFU/ml, SA-1 strains grew from 2.28 log CFU/ml to 2.66 log CFU/ml. According to the findings, <i>E. coli</i> O157:H7, <i>S. typhimurium</i>, and <i>S. aureus</i> can survive in kefir during fermentation.

The aim of this study was to investigate the use of Propionibacterium shermanii subsp. freudenreichii as a combined culture with Lactobacillus acidophilus (AP), Bifidobacterium animalis subsp. lactis (BP), Lactobacillus casei (CP) and Lactobacillus rhamnosus (RP) in probiotic dairy drink production. Although Propionibacterium spp. is used for many purposes including biopreservative and adjunct culture, in this study, probiotic dairy drinks containing P. freudenreichii were evaluated in terms of their physicochemical, rheological, microbiological and sensory properties. The results of the study showed that P. freudenreichii can also be suitable for the production of probiotic drinks and that there are no adverse effects on the product characteristics.

In this study, microbiological quality of 45 butter samples sold under market conditions at Manisa (Turkey) was investigated. Total coliform, total fecal coliform, Escherichia coli and yeast and mould counts were found between <

Objective: Although many techniques have been developed for food preservation, foodborne diseases are still an important problem. The studies aimed at solving this problem have increased in recent years using lactic acid bacteria with antimicrobial activities in foods. Materials and Methods:In this study, the antimicrobial effects of various lactic acid bacteria species, commercial yoghurt and probiotic yoghurt cultures and their supernatants on pathogen bacteria including Salmonella typmimurium NRLL E4463, Listeria monocytogenes Scott-A, Escherichia coli O157:H7, Staphylococcus aureus 6538P were examined by well diffusion and disc diffusion methods Results: It was determined that there were no statistical differences between the well diffusion and disc diffusion methods in terms of antimicrobial effects. It was also found that all of the lactic acid bacteria in MRS broth had substantial antimicrobial activities against the pathogens in both diffusion methods; however the antimicrobial effects of the supernatants obtained from cultures developed in media prepared from 10% skim milk powder showed diversity in terms of antimicrobial activity. Conclusion:These commercial cultures are thought to make a positive contribution with to help in the control of foodborne diseases. ÖZAmaç: Gıda muhafazası için birçok teknik geliştirilmiş olmasına rağmen, gıda kaynaklı hastalıklar hala önemli bir sorundur. Gıdalarda antimikrobiyal aktiviteye sahip laktik asit bakterilerinin kullanılmasıyla son yıllarda bu sorunu çözmeye yönelik çalışmalar artmıştır.Materyal ve Yöntem: Bu çalışmada piyasadan temin edilen çeşitli laktik asit bakterileri, yoğurt bakterileri ve probiyotik yoğurt kültürlerinin Escherichia coli 0157:H7, Listeria monocytogenes Scott-A, Salmonella typhimurium NRLL E 4463 ve Staphylococcus aureus 6538P gibi patojen bakteriler üzerine antimikrobiyal etkileri hem kuyu difüzyon hem disk difüzyon yöntemi ile incelenmiştir.Araştırma Bulguları: Antimikrobiyal etkiler açısından kuyu difüzyon ve disk difüzyon yöntemleri arasında istatistiksel olarak farklılık olmadığı belirlenmiştir. Her iki difüzyon yönteminde de MRS broth'taki laktik asit bakterilerinin tamamının patojenlere karşı önemli antimikrobiyal aktiviteye sahip olduğu, ancak% 10 yağsız süt tozundan hazırlanan ortamlarda geliştirilen kültürlerden elde edilen süpernatanların antimikrobiyal etkileri açısından çeşitlilik gösterdiği bulunmuştur.Sonuç: Bu ticari kültürlerin, gıda kaynaklı hastalıkların kontrolüne yardımcı olmak için olumlu bir katkı sağladığı düşünülmektedir.