Biobased defoamer compositions and methods of preparation thereof

A method of defoaming a system subject to foaming, comprising:

• treating the system with 0.001 to 10 wt. % of a defoamer composition, based on total weight of the system;
• wherein the defoamer composition comprises:
• (a) 80 to 100 wt. % of a decarboxylated rosin acid (DCR) having a density of 0.9 to 1.0 g/cm3, a flash point of 135 to 175° C., an acid value of <50 mg KOH/g, measured according to ASTM D465, and a viscosity of 15 to 60 cSt at 40° C., measured according to ASTM D-445;
• and
• (b) 0 to 20 wt. % based on total weight of the defoamer composition of at least a component selected from the group consisting of nanoparticles, surfactants, hydrophobic compounds, and mixtures thereof;
• and
• wherein the defoamer composition reduces a foam content by at least 20 volume % relative to the system without the defoamer composition.