New improved method for evaluation of growth by food related fungi on biologically derived materials

Biologically derived materials, obtained as commercial and raw materials (Polylactate (PLA), Polyhydroxybutyrate (PHB), potato, wheat and corn starch) were tested for their ability to support fungal growth using a modified ASTM G21-96 (American Society for Testing and Materials) standard as well as a new method where 10 mul of a spore suspension is placed in a spot on the test sample. The new method gave additional information about fungal growth on biologically derived materials, revealing a clear difference between survival and growth. PHB and PIA turned out to be most suitable for food packaging application as no significant growth was seen within 28 d of incubation at 30 degreesC.