Determination of the physicochemical and bioactive properties of homemade vinegar produced from various raw materials and the effects onb survival of foodborne pathogen microorganisms

Vinegar is a special product produced by yeasts and acetic acid bacteria from various raw materials containing carbohydrates. Within the scope of this thesis, it is aimed to examine the microbiological, physical and chemical properties as well as the bioactive properties such as antimicrobial and antioxidant of persimmon, pine cone and hawthorn (crataegus) vinegars produced by traditional methods obtained from different cities. In addition, the effects of vinegar samples on survival status of selected important food pathogens (Escherichia coli ATCC 25922, Staphylococcus aureus 6538 IP, Salmonella Typhimurium ATCC 14028, Listeria monocytogenes) at exposure times of 0, 15, 30 and 60 minutes were also determined. According to the results of the study, the titration acidity values of the vinegar samples were 0.98±0.02 - 3.15±0.00% in terms of acetic acid; pH values 3.61±0.00 - 3.91±0.01; density values 1.0017±0.00 - 1.0093±0.00 g/cm3; brix values 0.90±0.01 - 2.85±0.03%; dry matter values 0.17±0.21 - 3.07±0.24%; ash values 0.02±0.01 - 0.29±0.04%; L values with color values are 37.59±0.57 - 53.13±0.19; a values 0.77±0.03 - 5.52±0.77; b values - 3.64±0.16 - 20.80±0.33; ΔE values were determined as 43.20±0.60 - 53.20±0.18. Total phenolic content of the samples varied between were 5,53 – 157,44 mg GAE/ 100 mL. Antioxidant capacity results of vinegar samples according to TEAC method 8,93 – 11,76 µM TE.mL-1TA. It was determined that the antioxidant scavenging capacity results of vinegar samples according to DPPH method were 18,28 – 85,33%. When the microbiological properties of vinegar samples were evaluated, acetic acid bacteria count were 1.86±0.01 - 10.96±1.20 log CFU/mL; lactic acid bacteria count were 0.00 - 6.62±0.72 log CFU/mL; yeast-mold counts were found to vary between 0.00 - 7.49±0.07 log CFU/mL. Among the vinegar samples, the highest antimicrobial effect with hawthorn vinegar was obtained against Escherichia coli ATCC 25922 with a zone diameter of 23.75±5.30 mm, while the lowest antimicrobial effect with the hawthorn vinegar samples was obtained against Staphylococcus aureus 6538 IP with a zone diameter of 6.50±0.71 mm. According to the results of the viability of pathogenic microorganisms from vinegar samples at room temperature conditions at 0, 15, 30 and 60 minutes of exposure, when the effects of vinegar samples on the survival status of pathogen inhibition performed with vinegar samples varies between 1 and 5 logarithmic units. As a result, it was determined that homemade persimmon, pine cone and hawthorn vinegars produced by traditional methods have the potential to be used as natural antimicrobials on foodborne pathogens and their activities vary depending on their acid and total phenolic contents, target microorganisms and exposure times.