I have an idea but I'm not sure if it will work or even how to make it work:
OK, so if you take mineral oil (15-40 Carbons) and oxidize it (what oxidant should I use?) you should get an alcohol, like cetyl alcohol but longer chain, and if it is oxidized more it should become a carboxylic acid- a fatty acid. Is this correct so far?
Now, if this would produce fatty acids, could I 'esterize' it with glycerin to make a triglyceride? Can this be done? I think my terminology is wrong but I hope what I'm saying is clear. This is just something that I have been thinking about and want to try.