Poly (Lactic Acid) Films in Food Packaging Systems

Poly (lactic acid) (PLA) is a non - toxic, compostable bio based material derived from starch and/or sugar and has high mechanical strength and plasticity. It is accepted as GRAS (Generally Recognized as Safe) by the Food and Drug Administration (FDA) and suitable for using in food and beverage packaging. PLA is primarily obtained from lactic acid which can be produced from renewable substances such as potato, wheat and cor n starch. Petroleum based polymers cause an increase in fuel energy utilization and greenhouse gas emissions, however PLA is environmental friendly. Various polymers (protein, polycaprolactone (PCL) and polyhydroxy butrate (PHB)), fillers (wood, flax, and ramie) and additives have been combining with PLA in order to develop the performance of film and reduce the cost. On the other hand, PLA plays an important role in nanotechnology applications. Nan fillers like clay, montmorillonite and silica can be used for fortifying PLA composites. As a packaging material, PLA has a potential for manufacturing flexible films, extruded packages, containers of yoghurt, bottled water and juices, cups and lunch boxes. Moreover, in antimicrobial packaging, PLA is an excellen t material which is able to be successfully incorporated with plant extracts (e.g. lemon), essential oils (e.g. oregano oil), enzymes (e.g. lysozyme) and metals (e.g. silver) in order to develop antimicrobial characteristics. In this mini review, the signi ficance of PLA based packaging systems in food applications is discussed.