Wright et al. (1944) noted that the starting materials
used for alkali-catalyzed transesterification of glycerides
must meet certain specifications. The glyceride should
have an acid value less than 1 and all materials should be
substantially anhydrous. If the acid value was greater
than 1, more NaOH was required to neutralize the free
fatty acids. Water also caused soap formation, which
consumed the catalyst and reduced catalyst eciency.
The resulting soaps caused an increase in viscosity,
formation of gels and made the separation of glycerol
dicult. Bradshaw and Meuly (1944) and Feuge and
Grose (1949) also stressed the importance of oils being
dry and free (