Like a good wine, perfume will keep admirably away from light, humidity, air but also heat, a wine cellar would be the best option. Compared to a bottle with a screw cap, it seems obvious that a bottle with a spray will keep longer because the perfumed liquid will be less inclined to be in contact with the ambient air charged with oxygen and water. As the perfume is mainly composed of ethanol, like hydro-alcoholic gels, it is antiseptic and will not encourage the development of mould or the multiplication of bacteria. On the other hand, it is important to note that some natural raw materials contained in perfumes are more sensitive than others to oxidation, let us quote in particular the citrus notes, the powdery notes of violets (ionones), certain extracts of jasmine or orange blossom also colour with time, without the odour being affected. Oriental or woody fragrances are much more stable and will suffer less variation over time. While cosmetics are required by law to have a use-by date, there is currently no mandatory use-by date for alcoholic fragrances in France.