The additional cocoa butter is
necessary to provide sufficient lubrication
for all the added sugar particles to make the
mixture creamily fluid rather than pasty
when it melts. The higher the ratio of sugar
to ground nibs, the more added cocoa butter is required. Lecithin, whose use in
chocolate dates to the 1930s, coats the
sugar particles with the fat-like ends of its
molecules and helps reduce the amount of
cocoa butter needed to lubricate the parti-
cles; one part of lecithin replaces 10 parts of
butter. It typically makes up 0.3–0.5% of
chocolate weight.