Saturday, October 24, 2009


Fossil fuel based packaging materials have dominated for the last 6-7 decades making them omnipotent and their influence on day to day life of the common man is alarming. Though every one knows that these packaging materials are not environment-friendly, their convenience of use makes it difficult to wean people away from them. Regulating their use by the public by mandatory actions also does not seem to be succeeding, probably because of alternate option not being available to the public. Bio-degradable packing materials are increasingly being used though their availability in required quantities is uncertain. Reported development of a lactic acid based plastic material, commercially available and easily degradable within 90 days, therefore is a welcome news for the food industry.

"Poly Lactic Acid is a renewable plant based material, produced from the fermentation of starch from crops, (most commonly cornstarch or sugarcane in the United States), into lactic acid that is then polymerized. Its blends are used in a wide range of applications including computer and mobile phone casings, foil, biodegradable medical implants, molds, tins, cups, bottles and other packaging".

The ability of this bio-plastic to withstand temperatures up to 105C, its recycling properties and ease of usability make it an acceptable material for many applications including fabrication of containers, bottles, cups, etc. Its easy biodegradability without releasing any toxic substances to the environment unlike other plastics which take 700 years to degrade, makes it a 'green' packaging option with low carbon foot print.


1 comment:

Anonymous said...

I wish I could agree with you but if you take a closer examination of PLA you will see it has a lot of problems. PLA uses more petroleum in its development than plastic (see “How Green are Green Plastics”). They off-set this by buying energy credits. PLA will take 400-500 years to break down in a landfill, just like a normal plastic.PLA will also not break down in a backyard compost. The only place it will break down are in commercial and municipal composts that accept PLA.(see ASTM 6400 which is the standard PLA meets) There are 87 such locations in the US, so the chances of it ending up there are slim. They need high amounts of heat, aeration, and moisture than found in backyard compost. According to the EPA 2007 table of “Characteristics of Municipal Waste by Weight” plastic takes up 12% of a landfill. Paper and fiberboard takes up 32.7%.PLA and corn based ethanol are responsible for the shortage of food around the world and its increased prices. Nitrogen runoff from corn fertilizers has created a dead zone the size of the state of New Jersey in the Gulf of Mexico, where nothing can live.PLA is not a good choice.
There are biodegradable additives that can be put into plastics that enable them to biodegrade in landfills in 1-10 yrs. They then create methane which is now being harvested at 75% of all US landfills for energy to make electricity. PLA is the worst choice for biobased products. Look for others plants such as algae that can be made into containers and are backyard compostable.