MANUFACTURE OF MiLiK PowbER 277 
The difference between milk powder and condensed milk 
is mainly one of degree of concentration. It is not surprising. 
therefore, that the inventions of processes of manufacture of the 
two products date back to about the same period, the middle of 
last century, and in most cases the inventors of the one product 
had also in mind and gave due consideration to the possibilities 
of the other. 
The first commercially usable process was invented by 
Grimwade who secured a patent from the British Government 
in 1855. Eis process consisted briefly of first adding carbonate 
of soda or potash to the fresh milk, then evaporating in open 
jacketed pans and with constant agitation, until a dough-like 
substance was obtained; then adding cane sugar; the mixture 
was then pressed between rollers into ribbons, further dried 
and then pulverized. The alkah, in the form of carbonate of 
soda or potash, was added in order to render the casein more 
soluble, and the purpose of the admixture of the sugar was to 
produce granulation of the dough toward the end of the process 
facilitating the removal of moisture during the later stages of the 
drying process. ‘The evaporation in open pans was later super- 
seded by the use of the vacuum pan. ‘Phe Grimwade process of 
manufacturing milk powder was in practice for some years. 
Since the introduction of the Grimywade process, several 
modifications thereof have been patented, and numerous new 
processes for desiccating milk, that involve principles entirely 
different from the Grimwade process, have been invented, have 
found wide commercial application and have practically super- 
seded the use of the earlier inventions. 
The perfection of processes suitable for the commercial 
manufacture of dried milk is of relatively recent origin and dates 
back largely to the closing years of the nineteenth century and 
the first decade of the twentieth centry. Up to that time the 
annual output of milk powder was comparatively small. But 
within the last score of years rapid progress has been made and 
the world war has lent this industry additional impetus. Today 
the annual production is assuming large proportions, especially 
that of powdered skim milk, though considerable quantities of 
powdered whole milk, powdered cream and powdered buttermilk 
are also manufactured, as shown below, 
