Effect of microbiological characteristics of raw milk on the quality of whole milk powder

The relationship between microbiological characteristics of raw milk and th e quality of high-heat whole powder made from it was investigated. To this end, 16 lots of milk standardized for fat and non-fat solids were used. Pow der average levels of mesophiles and psychrotrophs were 7.8 x 10(1) and 4.0 x 10(1) CFU/g respectively, and these values correlated positively (P < 0. 05) with the corresponding raw milk counts (8.1 x 10(6) and 1.8 x 10(7) CFU /g, respectively). A significant positive correlation (P < 0.05) was also o bserved between raw milk psychrotroph counts and titratable acidity of milk powder (range: 0.15 - 0.19 as % lactic acid). Samples of powder produced f rom raw milk with higher psychrotroph levels were found to have higher inso lubility indexes, yet this relationship was not statistically significant. The importance of milk hygienic control as a basic instrument to warrant co mmercial milk powder quality is discussed.