ABSTRACT
An alternative to provide a desirable protection of milk against light is opaque fiberboard packaging. Another option is the employment of packaging containers based on dyed plastics with protective light capacity. Foods’ light sensitivity depends on many factors, including the strength of the light source and type of light that it emits, besides light-source-food distance, exposure time, optical properties of packaging materials, oxygen concentration inside the packaging and storage temperature. Plastic packaging is one of the most important contributors for protecting food from spoiling. Biodegradation is a process in which naturally-occurring microorganisms, such as bacteria, fungi, or algae act on the polymer material breaking down completely into non-plastic and non-toxic constituents. Mechano-chemical degradation of polymers takes place under mechanical stress, where molecular chains break down as a result of a mechanical force or under shear. Light exposure may cause significant photo-degradation of polymers, which results in breaking of polymer chains, production of free radicals and reduction of molecular weight.
