_L_ _L_
_t_ = ---- + 0.2_F_, and _T_ = ----- + 1.2_F_,
4 4
in which _L_ represents the reading of the lactometer. By the addition
of the constant factor 0.14 the results calculated by the formula of
Babcock are the same as those obtained by the method of Richmond.
In the following table are given the solids not fat in milks as
calculated by Babcock’s formula. To obtain the total solids add the
per cent of fat to solids not fat. To obtain total solids according to
Richmond’s formula increase that number by 0.14.
TABLE SHOWING PER CENT OF SOLIDS NOT FAT IN MILK CORRESPONDING
TO QUÉVENNE’S LACTOMETER READINGS AND PER CENT OF FAT.
Per
cent Lactometer reading at 60° F.
of
fat. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36.
0.0 6.50 6.75 7.00 7.25 7.50 7.75 8.00 8.25 8.50 8.75 9.00
0.1 6.52 6.77 7.02 7.27 7.52 7.77 8.02 8.27 8.52 8.77 9.02
0.2 6.54 6.79 7.04 7.29 7.54 7.79 8.04 8.29 8.54 8.79 9.04
0.3 6.56 6.81 7.06 7.31 7.56 7.81 8.06 8.31 8.56 8.81 9.06
0.4 6.58 6.83 7.08 7.33 7.58 7.83 8.08 8.33 8.58 8.83 9.08
0.5 6.60 6.85 7.10 7.35 7.60 7.85 8.10 8.35 8.60 8.85 9.10
0.6 6.62 6.87 7.12 7.37 7.62 7.87 8.12 8.37 8.62 8.87 9.12
0.7 6.64 6.89 7.14 7.39 7.64 7.89 8.14 8.39 8.64 8.89 9.14
0.8 6.66 6.91 7.16 7.41 7.66 7.91 8.16 8.41 8.66 8.91 9.16
0.9 6.68 6.93 7.18 7.43 7.68 7.93 8.18 8.43 8.68 8.93 9.18
1.0 6.70 6.95 7.20 7.45 7.70 7.95 8.20 8.45 8.70 8.95 9.20
1.1 6.72 6.97 7.22 7.47 7.72 7.97 8.22 8.47 8.72 8.97 9.22
1.2 6.74 6.99 7.24 7.49 7.74 7.99 8.24 8.49 8.74 8.99 9.24
1.3 6.76 7.01 7.26 7.51 7.76 8.01 8.26 8.51 8.76 9.01 9.26
1.4 6.78 7.03 7.28 7.53 7.78 8.03 8.28 8.53 8.78 9.03 9.28
1.5 6.80 7.05 7.30 7.55 7.80 8.05 8.30 8.55 8.80 9.05 9.30
1.6 6.82 7.07 7.32 7.57 7.82 8.07 8.32 8.57 8.82 9.07 9.32
1.7 6.84 7.09 7.34 7.59 7.84 8.09 8.34 8.59 8.84 9.09 9.34
1.8 6.86 7.11 7.36 7.61 7.86 8.11 8.36 8.61 8.86 9.11 9.37
1.9 6.88 7.13 7.38 7.63 7.88 8.13 8.38 8.63 8.88 9.14 9.39
2.0 6.90 7.15 7.40 7.65 7.90 8.15 8.40 8.66 8.91 9.16 9.41
2.1 6.92 7.17 7.42 7.67 7.92 8.17 8.42 8.68 8.93 9.18 9.43
2.2 6.94 7.19 7.44 7.69 7.94 8.19 8.44 8.70 8.95 9.20 9.45
2.3 6.96 7.21 7.46 7.71 7.96 8.21 8.46 8.72 8.97 9.22 9.47
2.4 6.98 7.23 7.48 7.73 7.98 8.23 8.48 8.74 8.99 9.24 9.49
2.5 7.00 7.25 7.50 7.75 8.00 8.25 8.50 8.76 9.01 9.26 9.51
2.6 7.02 7.27 7.52 7.77 8.02 8.27 8.52 8.78 9.03 9.28 9.53
2.7 7.04 7.29 7.54 7.79 8.04 8.29 8.54 8.80 9.05 9.30 9.55
2.8 7.06 7.31 7.56 7.81 8.06 8.31 8.57 8.82 9.07 9.32 9.57
2.9 7.08 7.33 7.58 7.83 8.08 8.33 8.59 8.84 9.09 9.34 9.59
3.0 7.10 7.35 7.60 7.85 8.10 8.36 8.61 8.86 9.11 9.36 9.61
3.1 7.12 7.37 7.62 7.87 8.13 8.38 8.63 8.88 9.13 9.38 9.64
3.2 7.14 7.39 7.64 7.89 8.15 8.40 8.65 8.90 9.15 9.41 9.66
3.3 7.16 7.41 7.66 7.92 8.17 8.42 8.67 8.92 9.18 9.43 9.68
3.4 7.18 7.43 7.69 7.94 8.19 8.44 8.69 8.94 9.20 9.45 9.70
3.5 7.20 7.45 7.71 7.96 8.21 8.46 8.71 8.96 9.22 9.47 9.72
3.6 7.22 7.48 7.73 7.98 8.23 8.48 8.73 8.98 9.24 9.49 9.74
3.7 7.24 7.50 7.75 8.00 8.25 8.50 8.75 9.00 9.26 9.51 9.76
3.8 7.26 7.52 7.77 8.02 8.27 8.52 8.77 9.02 9.28 9.53 9.78
3.9 7.28 7.54 7.79 8.04 8.29 8.54 8.79 9.04 9.30 9.55 9.80
4.0 7.30 7.56 7.81 8.06 8.31 8.56 8.81 9.06 9.32 9.57 9.83
4.1 7.32 7.58 7.83 8.08 8.33 8.58 8.83 9.08 9.34 9.59 9.85
4.2 7.34 7.60 7.85 8.10 8.35 8.60 8.85 9.11 9.36 9.62 9.87
4.3 7.36 7.62 7.87 8.12 8.37 8.62 8.88 9.13 9.38 9.64 9.89
4.4 7.38 7.64 7.89 8.14 8.39 8.64 8.90 9.15 9.40 9.66 9.91
4.5 7.40 7.66 7.91 8.16 8.41 8.66 8.92 9.17 9.42 9.68 9.93
4.6 7.43 7.68 7.93 8.18 8.43 8.68 8.94 9.19 9.44 9.70 9.95
4.7 7.45 7.70 7.95 8.20 8.45 8.70 8.96 9.21 9.46 9.72 9.97
4.8 7.47 7.72 7.97 8.22 8.47 8.72 8.98 9.23 9.48 9.74 9.99
4.9 7.49 7.74 7.99 8.24 8.49 8.74 9.00 9.25 9.50 9.76 10.01
5.0 7.51 7.76 8.01 8.26 8.51 8.76 9.02 9.27 9.52 9.78 10.03
5.1 7.53 7.78 8.03 8.28 8.53 8.79 9.04 9.29 9.54 9.80 10.05
5.2 7.55 7.80 8.05 8.30 8.55 8.81 9.06 9.31 9.56 9.82 10.07
5.3 7.57 7.82 8.07 8.32 8.57 8.83 9.08 9.33 9.58 9.84 10.09
5.4 7.59 7.84 8.09 8.34 8.60 8.85 9.10 9.36 9.61 9.86 10.11
5.5 7.61 7.86 8.11 8.36 8.62 8.87 9.12 9.38 9.63 9.88 10.13
5.6 7.63 7.88 8.13 8.39 8.64 8.89 9.15 9.40 9.65 9.90 10.15
5.7 7.65 7.90 8.15 8.41 8.66 8.91 9.17 9.42 9.67 9.92 10.17
5.8 7.67 7.92 8.17 8.43 8.68 8.94 9.19 9.44 9.69 9.94 10.19
5.9 7.69 7.94 8.20 8.45 8.70 8.96 9.21 9.46 9.71 9.96 10.22
6.0 7.71 7.96 8.22 8.47 8.72 8.98 9.23 9.48 9.73 9.98 10.24
=449. Determination of Ash.=—In the determination of the solid residue
obtained by drying milk, it is important to observe the directions
already given (=28-32=).
In the direct ignition of the sample, a portion of the sulfur and
phosphorus may escape oxidation and be lost as volatile compounds.
This loss may be avoided by the use of proper oxidizing agents or by
conducting the combustion as heretofore described.[430] In the official
method, it is directed to add six cubic centimeters of nitric acid to
twenty of milk, evaporate to dryness and ignite the residue at a low
red heat until free of carbon.[431] It is doubtful if this precaution
be entirely sufficient to save all the sulfur and phosphorus, but
the method is evidently more reliable than the common one of direct
ignition without any oxidizing reagent whatever.