The methyl esters content and methyl esters yield in each
experiment were calculated from their content in the biodiesel
as analyzed by HPLC. The content (or purity) was defined as a
ratio of the weight of methyl esters, obtained from HPLC, to the
total weight of the top phase. The yield was defined as a ratio of
the weight of methyl esters, determined by HPLC, to the weight
of vegetable oil used