Most products, including detergents, waste and shopping bags made of compostable and biodegradable film, textiles, plastic materials, inks, paints and varnishes, can undergo chemical and physical changes during storage and use.
The rate at which these changes occur depends on the nature of the active constituents, the type of formulation, the packaging and, of course, the storage/use conditions (temperature, light and humidity). The product remains fit for use as long as these changes have no adverse effects on application and/or consumer safety. Stability data should be generated with the product stored in the proposed commercial packaging, under accelerated conditions and/or via long-term testing at room temperature or in ambient warehouse conditions.
Mérieux NutriSciences provides a wide range of aging conditions (link), including climatic and xenon chambers for artificial exposure to light and weathering (link), and appropriate methods to test performance changes (link to performance) for an extensive range of goods.