Abstract:
This work was to develop biodegradable foam trays from chitosan and two types of natural
polymer; cassava starch and fiber. Results showed that starch foam developed from 80% cassava
starch was thick, high density, and higher tensile strength (TS) and elongation (E) compared with
foam made from 20,40 and 60% cassava starch. For improvement of water absorption index (WAI)
and water solubility index (WSI) of starch foam, fiber from lemongrass and kraft was added into the
80% of starch foam. Although starch foam mixed with 30% kraft fiber had a lower W AI and WSI,
TS and E of starch foam were high and its properties were greater than starch foam mixed with
lemongrass fiber. Starch foam with 30% kraft fiber was then mixed with 2, 4, and 6% chitosan.
Foam produced from cassava starch, kraft fiber and 4% chitosan had a greater TS (944.40 kPa) and
E (2.43%) but WAI and WSI of starch foam were greater than the polystyrene foam. Foam
produced with starch, chitosan, and fiber was, thus, developed by adding two additives; soybean oil
and polyvinyl alcohol (PVOH). Results showed that 10% soybean oil and PVOH did not effect on
TS and E but the additives could decrease WAI and WSI of the starch foam. Foam made from
starch, fiber, chitosan mixed with 10% soybean oil and PVOH was applied for fresh cut pomelo. It
was found that fresh cut pomelo kept in foam tray with soybean oil for 3 days had a greater quality
than kept in foam tray with PVOH.