Hydrocolloid-based bioplastics: Degradation in characterized soils.

Three different type of bioplastics were studied. They were made of amylose only, argan proteins only, while the third type contained both polymers at a 1:1 ratio. Their degradation was studied in three different type of soils fully characterized regarding their composition. The rate of degradation was similar for the three type of bioplastics, even though some differences can be observed in relation to the type of soil. Amylose only-based bioplastics are degraded at the same rate in all three different oils, while the Argan-based bioplastics and Amylose-Argan proteins- based one are more resistant to degradation in the calcareous flood soil with a sandy clay loam texture and alkaline pH, namely soil B from the agricultural area of Castel Volturno (Naples, Italy). The soil fertility was also assessed by cultivating garden cress in the soils where the novel bioplastics were left to degrade. Results were compared with a commercial bioplastic, showing a rate of degradation faster than the commercial one. Thus, novel bioplastics can be defined as compostable since obey the definition described by the European label EN 13432.