The objective of this study was to evaluate changes in some physicochemical properties of milk during acidification. The milk samples were analyzed for titratable acidity expressed as % lactic acid (LA), pH, electrical conductivity (EC) and lactose content. In fresh milk LA and pH exhibit a weak negative correlation (r = -0.3210). When acid production starts, LA increases proportionally, whereas the pH decreases (r = -0.8043). The acidifying process induced concomitantly an increase in EC. The decrease in pH from 6.578±0.088 to 5.732±0.195, and in lactose content from 5.469±0.256g% to 4.97±0.385g% was accompanied by an increase in EC from 5.337±0.434 mS/cm to 5.940±0.493 mS/cm.