Blue discoloration in fresh mozzarella cheese (FMC) is a defect caused specifically by Pseudomonas fluorescens. In the current study, lactose oxidase (LO) was demonstrated to be an effective hurdle to prevent the formation of blue color defects in FMC. In cheese produced through direct acidification (DA) by addition of citric acid, surface application of LO at a concentration of 1.2 g/L resulted in retention of conventional color characteristics; a concentration of 0.12 g/L also performed favorably, depending on variables such as product composition or initial contamination level. A LO concentration of 0.012 g/L did not show an inhibitory effect. Quantification of LO’s effects on blue discoloration in fresh mozzarella produced by starter fermentation (SF) revealed less consistency than that seen with DA FMC. However, based on the researchers’ visual assessments, the 1.2 g/L concentration performed the best out of those investigated, with obvious blue coloration occurring in only 1 out of 6 samples. This study demonstrates a promising clean-label approach to prevent blue color defects in FMC; further studies need to be conducted to fine-tune this process depending on the method used for acidification of cheese, potential initial levels of contamination, and packaging applied.