Biodegradation of kafirin and zein films WP3

Method Based on ASTM methods: D , D , and D Film strips cut and mounted in 35mm slide mount Compost used at 2 moisture levels 37%, 60%, pH 7.8 Samples buried in compost in plastic buckets, closed and placed in the dark in an incubator

Temperature Regime: 35°C - 2 days 58°C - 4 days 50°C- until day 26 for optimal composting conditions 35° - for final 2 days of test Buckets aerated daily for 1 hour, then moisture corrected to 37 or 60% using a mist sprayer Samples taken at 5 day intervals

A B CD E AB DC E AB D DAYS Biodegradation of Films

Conclusions Kafirin films are biodegradable within 20 days under low moisture conditions and within 10 days under high moisture conditions Microwaving and plasticisation extends film life by a few days Modification of films with tannins extends film life by a further few days