Provided herein are mixtures, emulsions and other additives for use in manufacturing gypsum wallboard. The mixtures and emulsions may be wax-based emulsions or wax-free mixtures or emulsions, with wax-based emulsions including water, at least one wax, a dispersant which may include sulfur or a sulfur-containing group, and an additive comprising an organic titanium compound or organic zirconium compound. Mixtures may also be prepared including water, a dispersant; and an additive comprising an organic titanium compound or organic zirconium compound. Gypsum slurries may be prepared using such emulsions and mixtures and/or through addition of an organic titanium compound or organic zirconium compound.