No I don't have any advice on the yellowing of clove oil. However look at your paintings. Where is this potential yellowing going to show up? I suggest in pure white passages, that is the brightest of highlights. Probably not going to be noticeable for a hundred years or so. I for one like to see some patina as a badge of honor in ancient artworks. Further, I suggest the varnish will yellow long before the clove oil.
Nice colors. Suggest cropping the top to have as much space above the flowers as below the vase. I would also leave out the dado rail which does not contribute. I would intensify light and shadow a bit. Try not to have the vase dead centre, perhaps a small metal object beside the vase?