A few studies have been published on the distribution of oxytetracyline (OTC) residues present in milk among cheese, whey, and milk protein fractions, throughout cheese-making, most of them, focused on the effect of pasteurization and Ultra High Temperature (UHT) treatments, and carried out on cow milk. This study aimed to investigate the impact of a thermisation treatment of ovine milk spiked with oxytetracycline at MRL (maximum residue limit) and half MRL, on the fate of the molecule, and the effect of OTC residues on starter culture development and cheese composition. The antibiotic recovery and partition from milk into whey and cheese were assessed by liquid chromatography-high resolution mass spectrometry (LC-HRMS). Starter and non-starter microflora development was monitored by viable plate counts. Milk thermisation did not affect OTC recovery, partition and cheese chemical composition. On a dry matter basis, an OTC reduction between 15 and 19% was calculated in 60-day cheese, at MRL and half MRL, respectively. OTC caused a dose-dependent difference in the time required to reach pH 5.60, which was significantly higher (P < 0.05) at MRL level compared to half MRL and control, allowing coliform bacteria to reach 6 log CFU g⁻¹ in 1-day MRL OTC cheeses.

在整个奶酪制作过程中，已经发表了一些关于奶酪中乳清中氧四环（OTC）残留物在奶酪，乳清和牛奶蛋白成分中的分布的研究，其中大部分集中在巴氏灭菌法和超高温（UHT）的作用上。治疗，并在牛奶上进行。这项研究旨在调查以最大残留限量（MRL）和最大残留限量（MRL）一半对加有土霉素的羊奶进行热化处理对分子命运的影响，以及OTC残留物对起子培养物发育和奶酪成分的影响。通过液相色谱-高分辨率质谱法（LC-HRMS）评估了抗生素从牛奶中回收和分配到乳清和奶酪中的过程。起始菌和非起始菌的菌群发育通过活板计数进行监测。牛奶热化处理不会影响OTC的回收，分配和奶酪的化学成分。以干物质为基础，计算出60天奶酪的OTC降低幅度为15％至19％，分别为MRL和MRL的一半。OTC导致达到pH 5.60所需时间的剂量依赖性变化，与半数MRL和对照组相比，在MRL水平上显着更高（P <0.05），从而使大肠菌群细菌达到6 log CFU g^-1天的MRL OTC奶酪。