Herby cheese (Otlu peynir) is widely produced and consumed in eastern parts of Turkey, and is generally made from sheep milk. The biogenic amines and organic acids content, microbiological, and chemical properties of Herby cheese were determined on 30 samples obtained from retail markets in East Anatolia Region, Turkey. The most important biogenic amines were tyramine (range 18.0-1125.5 mg kg −1 ), followed by cadaverine varied from not detected to 1844.5 mg kg −1 . Histamine content generally was found higher than 100 mg kg −1 . The concentration of amines in some cheeses was much higher than the toxic dose limits. Generally, total amine content was found high in samples that had high nitrogen fraction and organic acids value. Levels of biogenic amines were significantly correlated with the organic acids of Herby cheese. The basic organic acid was found the lactic acid ranging from 585.4 to 26480.3 mg kg −1 , followed by butyric acid varying between 314.8 and 7329.6 mg kg −1 values. Lipolysis and nitrogen fraction were determined high in ripened Herby cheese samples. Coliform counts of samples showed lower than 100 cfu g −1 in the samples. Significant (p < 0.01) positive correlation was observed between acetic acid and phenylethylamine, putrescine, cadaverin, histamine, and tyramine.

Thyme oil nanoemulsions (TONa and TONb), having 219 nm and 163 nm diameters, were successfully prepared by using sonication technique. Zeta potential (ZP) and polydispersity indexes (PDI) of TONa and TONb were defined to be 19.77, 0.24 and −24.80, 0.054, respectively. It was determined that zeta size values of TONs might have played a role on the inhibition of Pseudomonas aeruginosa, Escherichia coli, Salmonella typhimurium. All bacteria tested by agar diffusion method were gram-negative bacteria that could be mostly found in fish fillets. Within 9 days cold storage period, TMAB growth in fish fillets treated with TONb was successfully reduced from 6.42 to 4.62 log CFU/g (change: 28%). In addition, as compared with control group samples, TPB growth of the same group was limited by 1.51 log CFU/g (from 7.93 to 6.42 log CFU/g). The results suggested that treatment of the fish fillets with the TONs would be a useful and practical nano application to delay microbial growth in fish fillets. Practical applicationsThyme oil nanoemulsions (TONa and TONb) with a lower diameter than 219 nm have been successfully obtained. Antibacterial effects of TONa and TONb nanoemulsions have been revealed before treatment with fish fillets. The results revealed that TONs could be successfully used for the limitation of microbial spoilage of fish fillets stored at 4 C for 9 days. In this respect, the nano application with rapid and cost-effective has been presented for the fishery processing industry.

The effects of storage temperature (+4 degrees C and -18 degrees C) and packaging method (nonvacuum and vacuum) on biogenic amines in Motal cheese during storage periods were investigated. In addition, dry matter, titratable acidity, total nitrogen, water-soluble nitrogen, trichloroacetic acid-soluble nitrogen, phosphotungstic acid-soluble nitrogen, free amino group (proteolysis), electrophoretic patterns of casein, and amounts of lactic acid bacteria and coliforms were determined. Storage period had a significant effect on all of the biogenic amines. When compared with vacuum packaging, normal packaging had higher amounts of putrescine, cadaverine, histamine, and tyramine. Coliforms were not found at detectable levels (<100cfu/g) in all cheese samples. Results of urea-PAGE analysis of cheese samples were in good agreement with biogenic amine results and other proteolysis parameters.

In this study, the effects of sirmo (Allium vineale L.), mendi (Chaerophyllum macropodum Boiss.) and siyabo (Ferula rigidula DC.) on mineral compositions of herby cheese produced from raw and pasteurized milk in brine and vacuum package during 90 days ripening were determined. Macroelements (Ca, Mg, Na, K) and micro elements (Fe, Zn, Mn) concentration of herby cheese samples were examined by Inductively Coupled Plasma-Optical Emission Spectrometer (ICP-OES). It was determined that the mineral concentration was changed from highest to lowest Na>Ca>K>Mg>Zn>Fe>Mn in the herby cheese. The highest mean concentration of Na was found in Sirmo added cheeses manufactured from raw milk in brine on the second day of ripening and the lowest mean concentration of Mn was found in Sirmo added cheeses produced from pasteurized milk in brine at the end of 90 days. Na, Ca, K, Mg, Zn, Fe and Mn content of cheeses in brine and vacuum package decreased during ripening period.

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