Socio-economic conditions compel the milk industry and producers to undertake measures aimed at increasing production profitability. Above all, the specifics of long-ripened cheese production requires augmenting the casein content in milk. This is however obstructed by the lack of an established economically justified threshold value for this ingredient that would guarantee the efficiency of cheese production and correct settlement of accounts with the breeders. The presented study results for the 45th batch of milk refer to ingredients that decide the efficiency of the production of cheese from milk with different casein levels. The raw milk with a higher casein content contained 0.20% more protein (P ≤ 0.014) and 0.08% more k-casein (P ≤ 0.047). In comparison to the milk with a lower casein content, the obtained whey and cheese slurry contained 0.09% less protein (P ≤ 0.035) and 1.92% more dry non-fat matter (P ≤ 0.049). This milk also yielded 0.4% more cheese (P ≤ 0.039). It can be assumed that the selection of milk pools on the basis of their casein contents can improve production efficiency and set new trends in assessments of processing milk usability.