A method for producing a high viscosity, low volatiles blown stripped plant-based oil is provided. The method may include the steps of: (i) obtaining a plant-based oil； (ii) heating the oil to at least 90° C.； (iii) passing air through the heated oil to produce a blown oil having a viscosity of at least 50 cSt at 40° C.； (iv) stripping the blown oil from step (iii) to reduce an acid value of the blown oil to from 5 mg KOH/g to about 9 mg KOH/g； (v) adding a polyol to the stripped oil from (iv)； and (vi) stripping the oil from step (v) to reduce the acid value of the oil to less than 5.0 mg KOH/g or less.
