Lipid particle-localized triacylglycerol (TAG) lipase. The lipid droplet/particle is a lipid storage compartment which serves as a depot of energy and building blocks for membrane lipid biosynthesis. Involved in the mobilization of the non-polar storage lipids triacylglycerols (TAGs) from lipid particles by hydrolysis of TAGs, releasing and supplying specific fatty acids to the appropriate metabolic pathways. a triacylglycerol + H2O = a diacylglycerol + a fatty acid + H(+) Partially retained in the endoplasmic reticulum in cells lacking triacylglycerols.