LABEC M-MIA-LA - Manual (Page 65)

Ultrasonic milkanalyser
Operation manual 04.11.09 63/107
stirred and titrated with 0,1 N soda caustic, till slight rose color is recovered.
At the second titration the volume of the used soda caustic is measured.
For sheep milk
Casein content in sheep milk is determined on the same way. The only
difference is that instead of 4 cm
3 38-40 % formalin in the milk are added 6
cm 3 , and the standard/reference sample is prepared with 1 cm 3 4 % solution
of cobalt sulphate.
4.7. Calculations
The quantity of the 0,1 N soda caustic in cm 3 , used in the second titration,
multiplied by the coefficient 0,7335 is equal to the casein content in the milk
in percentages.
The following tables could be used for quicker readings of casein's
percentage on the base of used cm
3 0,1 N soda caustic:
Table I
Calculation of casein content in the cow milk on the base of used cubic
centimeters 0,1 N soda caustic:
0,1 n NaOH cm 3 Casein% 0,1 n NaOH cm 3 Casein % 0,1 n NaOH cm 3 Casein %
3,00 2,20 3,35 2,46 3,70 2,71
3,05 2,24 3,40 2,49 3,75 2,75
3,10 2,27 3,45 2,53 3,80 2,79
3,15 2,31 3,50 2,56 3,85 2,82
3,20 2,35 3,55 2,6 3,90 2,86
3,25 2,38 3,60 2,64 3,95 2,90
3,30 2,42 3,65 2,68 4,00 2,93