In early March 2010, the European Union approved a genetically mofidied potato crop to be grown in Europe, the first one since in 1998 Monsanto’s MON 810 maize was approved, which is engineered to be resistant to the European corn-borer caterpillar.
The approved potato variety is Amflora, developed by BASF for industrial applications such as lubricants, sprays and animal feed. When the news came out, some people suggested that it was to be used in the production of bioplastics. I always considered a bit risky to used GMO in the production of a product that bases part of its market appeal on environmental benefits and considered that European producers of bioplastics have an advantage over producers elsewhere that do use GMO crops as feedstock. It has to be said that resistance towards GMO is mostly a European concern and that public resistance to them in other world regions is not that high.
Naturally produced starch is a combination of amylose and amylopectin, both polymers of glucose. The main difference is that amylose is a linear polymer while amylopectin is branched. Amflora is genetically modified to produce only amylopectin, the more interesting component for most industrial applications, as it is not water soluble. However, for production of bioplastics in particular, amylose is more interesting than pure amylopectin, so the Amflora variety is not of particular interest for bioplastic producer. For example, Plantic Technologies products are made with high amylose corn starch as base. In my opinion, there is no need for genetic modifications to obtain better, sustainable materials. In some cases, there isn’t even the need for a crop to be used to produce a bioplastic. Rodenburg Biopolymers for example use as feedstock for their product, Solanyl, the waste generated by the Dutch potato processing industry, which discards 40% in weight of the potatoes. I think this approach is a much more sustainable one than any other, instead of modified crops or even crops that may compete with the food stream at all.
You can find more information on the science of starch based materials in the excelent blog by Luc Averous, to whom I have to thank for sharing this particular link with me: http://www.biodeg.net/biomaterial.html through our Bioplastics group in Linkedin.