Stearin or glycerol tristearate or tristearoylglycerol or Glycerol trioctadecanoate is a triglyceride that is composed of glycerol in which all three hydroxy groups have been esterified with stearic acid (octadecanoic acid). Glycerol tristearate finds application as hardening agent in the manufacture of candles and soap. It also has a role as a plant metabolite. glycerol tristearate is a common constituent of animal and vegetable fats.