Investigation of the changes during the storage period of probiotic added Izmir tulum cheese produced using cow and buffalo milk with different packaging techniques

In this research, control (Lactococcus lactis ssp. lactis + Lactococcus lactis ssp. cremoris) and probiotic-added (Lactococcus lactis ssp. lactis + Lactococcus lactis ssp. cremoris + Lactobacillus acidophilus) Izmir Tulum cheeses were produced from cow (100%) and buffalo (100%) milk. Cheese samples were ripened in brine at 14-15˚C for the first 15 days of storage, and in brine, vacuum and modified atmosphere packaging at 4-6˚C until the 90th day of storage. Vacuum and modified atmosphere packaging methods used as an alternative to ripening Izmir Tulum cheeses in brine; the composition, ripening, textural and organoleptic properties of cheese and its effects on the viability of Lactobacillus acidophilus were investigated. In addition, it was examined how different milk types, including cow and buffalo milk, used in the production of Izmir Tulum cheese, affected the quality characteristics of the cheese and the viability of Lactobacillus acidophilus. In this context, physical, chemical and microbiological analyzes of Izmir Tulum cheeses were performed on the 1st, 15th, 30th, 60th and 90th days of storage, and sensory analyzes were performed on the 90th day of storage. In our study, Izmir Tulum cheeses we produced from cow's milk varied dry matter values between 41,18-73,27%; ash values between 6,42-9,31%; fat values between 21,00-40,00%; salt values between 4,56-7,78%; protein values between 9,78-26,94%; ripening index values between 19,88-51,66%; aw values between 0,754-0,890; pH values between 4,64-5,40; lactic acid values between 0,78-2,37%; L* values between 82,46-92,45; a* values between 0,91-1,91; b* values between 9,00-16,91 during ripening. Izmir Tulum cheeses we produced from buffalo milk varied dry matter values between 46,41-74,87%; ash values between 6,41-9,28%; fat values between 26,50-46,00%; salt values between 4,22-7,79%; protein values between 9,12-22,44%; ripening index values between 20,74-53,22%; aw values between 0,731-0,869; pH values between 4,69-5,52; lactic acid values between %0,72-2,00; L* values between 78,02-90,16; a* values between 0,97-2,56; b* values between 6,75-11,66 during ripening. In addition, it was found that cheese samples produced from cow and buffalo milk and ripened in brine had higher ash, salt, aw and pH values than cheese samples ripened in vacuum and modified atmosphere packaging; it was determined that dry matter, fat, protein, ripening index, lactic acid, b*, hardness and springiness values were lower. In our research, the Lactobacillus acidophilus type bacterial values of cheese samples produced from cow's milk during the ripening period were 6,56-7,93 log cfu/g; ıt was determined that the Lactobacillus acidophilus type bacteria values of cheese samples produced from buffalo milk varied between 6,06-8,02 log cfu/g. It was concluded that the probiotic bacteria count of all cheese samples with Lactobacillus acidophilus added, produced from different milk types and ripened by different methods, was more than 106 cfu/g and had probiotic food properties. It was determined that ripening cheese samples produced from both cow and buffalo milk in vacuum and modified atmosphere packaging had a higher effect on preserving the viability of Lactobacillus acidophilus than ripening in brine. In addition, sensory evaluation results revealed that cheese samples produced from cow and buffalo milk and ripened in vacuum and modified atmosphere packaging were liked more than cheese samples ripened in brine. Research results have shown that buffalo milk, which has rich nutritional content, can be used in the production of Izmir Tulum cheese, which is among our traditional Tulum cheeses and is widely consumed. Processing buffalo milk into Izmir Tulum cheese is important in terms of obtaining high value-added dairy products from buffalo milk and expanding the product range of the cheese industry. Keywords: Izmir Tulum cheese, Buffalo milk, Cow milk, Lactobacillus acidophilus, Vacuum packaging, Modified atmosphere packaging