A useful tip I got from my sister , years ago, is to keep an open container of Bicarbonate of Soda (Sodium Bicarbonate) in the fridge, it absorbs smells!! and keeps your fridge smelling fresh then every 3 to six months make a solution from the contents of the container in warm water and wash out the interior of the fridge this helps clean the plastic interior and also removes residual smells that may be "stuck" to the plastic, then pour the remaining Bicarb solution down the kitchen drain, it helps to degrease it!!!