In recent years, with the awareness of people, the interest in natural and functional foods has increased. Sourdough is a dough piece in which industrial culture yeasts (Saccharomyces cerevisiae), endogenous yeasts, lactic and acetic bacteria from the air and the ingredients used (flour, water, etc.) are active. In sourdough fermentation, yeast and lactic acid bacteria work together to form the natural flora. It has been proven by studies that breads prepared from sourdough have many advantages such as greater volume increase, stronger aroma, better crumb structure and long shelf life. In addition, sourdough fermentation has very important positive effects on human health. Various additives (malt flours, emulsifiers, microbial enzymes, dairy products, soy flour and potato flour) are used to delay the staling of bread. In the production of sourdough bread, high quality and long shelf-life breads can be obtained without the need for these additives. Thus, both natural and additive-free and functional breads are produced. In this review, it is aimed to raise awareness by giving information about the advantages of using sourdough in bread production. In the study, the concept of sourdough was discussed and information was given about the content of bread prepared using sourdough and its benefits on health.

Developing alternative control methods such as using beneficial microorganisms and their metabolites to control the plant diseases has gained so much importance along recent years and research on this area are increasing day by day. In this study the possibilities of using microorganisms which have antimicrobial effects on controlling soil-borne fungi at strawberry production were investigated. Effects of different lactic acid bacteria (LAB) strains were studied in vitro and in vivo against the development of several soil-borne fungi. LAB were screened for antifungal activity by using cell free supernatant against Fusarium sp., Rhizoctonia sp., Macrophomina sp., Botrytis sp., Phtopythium sp., Cylindrocarpon sp. and Pestalotiopsis sp. Cell free supernatant of LAB isolates showed antifungal activity against fungi. In vitro effective strains of LAB were used in pot experiments to search their effects on fungal development and the development of the plant. While the antifungal effects of all LAB strains tested in vitro experiments exhibited promising results, in vivo experiments revealed similar effects on different fungi genera.

Yoghurt is the common fermented dairy product consumed worldwide and it is considered a potential source of probiotic bacteria (Lactobacilli and Lactococci). To assess the in-vitro probiotic properties of lactic acid bacteria, Lactococcus lactis subsp. lactis, Lactobacillus delbrueckii and Lactobacillus plantarum species isolated from yoghurt sold in different local markets of Chittagong region in Bangladesh were examined by morphological characteristics and biochemical tests. In the preliminary test, all isolates were grown well at acidic pH (pH 3-5) while the optimum growth temperature was 37°C and better growth was observed in the presence of 1-8% NaCl concentrations. In addition, the selected isolates were able to survive up to 3% bile salt concentrations while the best tolerance was at 1% bile salt. The strains successfully inhibited the growth of common pathogenic bacteria likely Escherichia coli, Pseudomonas aeruginosa, Salmonella Paratyphi, Staphylococcus aureus and Bacillus subtilis examined by in vitro growth inhibition test. Most of the isolated strains exhibited resistance pattern against ten commonly used antibiotics in foodborne illness in the country. However, the strains in yoghurt sold at Chittagong city have ideal probiotic characteristics and this fermented dairy product could be a potential source of human probiotic bacteria.

In the present study, we aimed to isolate and biochemically identify tyramine-producing lactic acid bacteria (LAB) from black and green fermented olive samples produced by traditional methods and obtained from different provinces of Turkey. A total of 36 LABs, including Enterococcus spp. (2 isolates), Lactobacillus spp. (16 isolates), and Lactococcus spp. (18 isolates) were isolated from the fermented olive samples. Among them, 27 isolates could decarboxylate tyrosine amino acid; however, the decarboxylase enzyme activity of the remaining 9 isolates was negative. The ability of LAB isolates with positive enzyme activity to produce tyramine was evaluated using high-performance liquid chromatography (HPLC), and 6 isolates were found to be significant tyramine producers in vitro, producing tyramine at concentrations ranging from 107.251 to 207.618 mg L–1.

Fermentation is known as a method that improves the nutritional value of foods in addition to preserving them. Various traditionally produced fermented foods such as yogurt, kefir, kombucha, some cheeses, sausages and pickles have probiotic potential. Hence, consumption of fermented foods plays an important role in modulating of gut microbiota and supplying positive effects on health. With the help of beneficial microorganisms, the intestinal barrier can be improved which induces the activity of the immune cells associated to the gut. In recent years, probiotics have been used in foods in order to produce functional foods that have the potential to improve gastrointestinal health. It is known that intestinal microbiota and probiotics can interact in immune system and these interactions provide positive health effects like reducing risk of hypertension, improving gut microbiota, regulating immune system, preventing diabetes, allergies and diarrhea. In this paper, fermented foods having probiotic potential and the effects of consuming these foods on the immune system are revised.

In this study, it was investigated that the inhibition effect of some lactic acid bacteria (Lactobacillus acidophilus NCC68, Lactobacillus casei Shirota, Lactobacillus rhamnosus (Ezal, commercial starter cultures)) which possessed with probiotic characteristics, against Bacillus cereus, Salmonella Enteritidis, Escherichia coli, Escherichia coli 0157:H7 ATCC 35150 and Staphylococcus aureus ATCC 25923. Besides, the inhibitory effect of probiotic cultures which used with meat and meat product additives that garlic extract over the antagonistic effects of sensitive pathogens were investigated in vitro. Consequently, the whole of lactic acid bacteria and garlic extract which were used in this study, showed inhibition effects against all selected pathogenic bacteria. Staphylococcus aureus ATCC 25923 was determined as the most sensitive pathogenic bacteria while Bacillus cereus was the most resistant bacteria against lactic acid bacteria and garlic extract. There was a distinctive increase in inhibition effects were observed by used of a combination with lactic acid bacteria and garlic extract.

In this research, biogenic amine types and quantity of Tulum and Kashar cheeses were determined. In addition, the relationship between biogenic amines and some microbiological-chemical properties of cheese samples were investigated. The contents of tryptamine, phenylethylamine, putrecine, cadaverine, histamine, tyramine of totally 40 samples (20 of each cheese) were examined. While only one sample of Tulum cheeses had no biogenic amines, different levels of biogenic amines were determined in other samples. No significant relation was confirmed between the biogenic amine quantity and total aerobic mesophilic bacteria, lactic acid bacteria, enterococci bacteria count, but there was a correlation between some biogenic amine contents and chemical properties which are tyrosine, lactic acid, pH, protein and ripening coefficient. Biogenic amine levels determined in the cheeses found below hazard limit values according to what legal limit.

Non-dairy probiotic functional foods are receiving considerable interest recently owing to the inability to cause allergy in certain segments of the population. Studies on probiotication were carried out to determine the suitability of kunun-zaki as food matrix for production of probiotic beverage using single and mixed culture of Pediococcus acidilactici KU7, Pediococcus pentosaceus CREC5 and Lactobacillus rhamnosus GG. Probioticated and un-probioticated kunun-zaki samples were designated PKZ and UPKZ, respectively. There was a significant difference in the viable count during storage. Viable counts of the LAB strains decreased with increasing storage time with P. acidilactici KU7 having the highest viability at the beginning and end of storage (3.43 ± 0.06 and 0.93± 0.12 x108 cfu/ml). There was a decrease in pH of the PKZ samples within the 1st and 3rd week with corresponding increase in lactic acid production (71.16 ± 0.01 – 441.39 ± 0.01). Marked increase in pH and a decline in lactic acid were observed at the 4th week of storage in all samples. Total soluble solids content of the beverage was observed to decrease with increasing storage time ranging from 8.25 ± 0.01-4.97± 0.01. There was no significant difference in pH and total soluble solids of UPKZ and colour of the PKZ and UPKZ samples during storage. All the PKZ samples were able to inhibit the growth of selected pathogens with marked variability amongst the samples. The UPKZ sample also showed slight inhibitory activity. The samples showed a decline in proximate and mineral composition at the end of storage. Sensory evaluation showed the PKZ samples were preferred over the UPKZ samples. This study shows that probioticated kunun-zaki can serve as a suitable non-dairy alternative to dairy probiotic formulations and would be of health benefits to potential consumers.

Pickles, which are known to have many nutritional and health benefits, have been used as a nutritional supplement in many cultures in recent years. Lactic acid bacteria, in its natural microbiota of pickle, which have various probiotic properties such as increased natural resistance to infectious diseases in the gastrointestinal system, prevention of various infections, and reduction in cholesterol level are effective in this. In our study, various combinations of salt, vinegar and lemon acid were made to produce cabbage pickled and it was determined how it affected the natural microbiota during fermentation. When the results were evaluated in terms of the viability of lactic acid bacteria, the best results were obtained with 5.35 logarithms in the G2 produced using only 5% lemon juice from eight different groups, one of which was a control. In the G3 which was produced using 5% vinegar, this number was determined as 1.82 logarithms. At the end of fermentation, it was determined that the coliform groups in the experimental groups lost their viability. Yeasts were completed this process with an average of 1 logarithm. When all test groups were examined in terms of all microbiological results was showed that the production of 5% lemon juice G2 has optimally results in terms of growing LAB and inhibition the undesirable microbial groups

The study aimed to evaluate the pH, water activity (aw), residual nitrite, lactic acid bacteria, Micrococcus/Staphylococcus, Enterobacteriaceae and yeast-mould in fermented sausage samples from different firms. A total of 30 sucuk and 30 heat-treated sucuk samples were taken from 10 different brands with different batch numbers. According to analysis results, all samples, with the exception of some heat-treated sucuk samples from one brand, provided pH values that were within the permitted limit of regulation. For sucuk, mean aw value of only one brand was below 0.90, while aw values for heat-treated sucuk were in the range of 0.928 to 0.957. All samples had residual nitrite levels less than 15 mg/kg (in the range of 7.84-14.80 mg/kg). Yeast-mould and Enterobacteriaceae numbers were often below <2 log cfu/g. The number of Staphylococcus and Micrococcus showed a wide variation in both products which was <2 - 5.96 log cfu/g for sucuk and <2 - 7.85 log cfu/g for heat-treated sucuk. Lactic acid bacteria counts varied between 2-<4.0 log cfu/g in 40% of heat-treated sucuk samples. In sucuk, the number of lactic acid bacteria was <6 log cfu/g in 23.33% of the samples, and 6-<8 log cfu/g in 50% of the samples.