301 



CHAPTER VI. 



BUTTER. 



Ci5NTHiNTs.— Definition o£ Butter— Conaposition— Theory of Cliurniug- 

 The Proximate Analysis of Butter— Tlie Analysis of Butter Fat- 

 Preparation of the Fat for Analysis— Recapitulation of Properties 

 —Estimation of Volatile Fatty Acids— Saponification Equivalent- 

 Soluble and Insoluble Fatty Acids— Colour Tests for Adulterants 

 —Behaviour of Butter Fat with Solvents— Iodine and Bromine 

 Absorption— Heat Evolved by Sulphuric Acid— Physical Examination 

 of Butter Fat— Microscopic Examination— Density— Refractive Index 

 —Viscosity— Melting Point— Detection of Adulteration of Butter- 

 Infiuenoe of Keeping on Butter— ButtermUk— Chemical Control of 

 Churning Operations. 



Deflnition. — Butter is the substance produced by churuiug 

 milk or cream, duriug which process the fat globules coalesce 

 to form granules ; when freshly churned, butter has the appear- 

 ance of a fine granular mass; but, after being worked, this 

 assumes a structure homogeneous to the naked eye. 



Composition. — Storch gives the followino; mean composition 

 to butter :— 



TABLE LXXI. — Composjtion of Buttee. 



He further argues that the milk-sugar must all belong to the 

 buttermilk, which fills the spaces between the fatty portion ; 

 and, from the composition of the buttermilk, calculates the 

 proportion of water, proteins, and ash belonging to this. 



