BS 734-2:1959

Co-operating organizations
Foreword
Specification
1 Scope
2 Determination of density
3 Corrections to observed hydrometer readings
4 Determination of S.N.F. content
Appendix A Derivation of the equations
Appendix B Determination of corrections for scale
            errors
Tables
1 Temperature corrections to hydrometer readings
2 Percentage of solids-not-fat (S.N.F.) (with milk fat
   in liquid state)
3 Percentage of solids-not-fat (S.N.F.) (with milk fat
   in solid state)

Density determination of milk at 20°C with milk fat (a) in liquid state and (b) in solid state, using hydrometers reading at the top of the milk meniscus. Tables relating SNF content to densities determined under (a) and (b) with known milk fat content.

Part 2 of this British Standard specifies procedures for determining the density of milk with the fat either wholly in the liquid state or wholly in the solid state and provides tables relating the known fat content and measured density to percentage of S.N.F. in the milk under test.

Of the hydrometers specified in Part 1 of this standard the Nos. 1 and 1A hydrometers are the most accurate; 225 ml (8 ft. oz) of milk is ample for these hydrometers. The Nos. 2 and 2A hydrometers can be used with 150 ml (5 fl. oz) of milk while the Nos. 3 and 3A hydrometers may be used with as little 1as 90 ml (3 fl. oz) of milk but the use of such a small sample should be avoided whenever possible.