Preparation and Characterization of Biodegradable Thermoformed Tray from Thermoplastic Cassava Starch/poly(lactic acid) Blend Incorporating Encapsulated Black Pepper Essential Oil

Abstract

This current research aims to study the preparation and characterization of thermoformed trays from poly(lactic acid)/thermoplastic cassava starch (PLA/TPS) and PLA/TPS incorporating encapsulated black pepper essential oil. The weight ratio of PLA: TPS was fixed at 60:40. The black pepper essential oil (BP) was encapsulated in hydroxypropyl-beta-cyclodextrin (HPBCD) and maltodextrin-gum arabic (MG) using spray-drying technique. The BP-HPBCD and BP-MG varied as 10%, 15%, and 20% w/w. PLA/TPS, PLA/TPS/BP-HPBCD, and PLA/TPS/BP-MG thermoformed trays were successfully prepared by using thermoforming machine with a heating temperature of 340 °C, a heating time of 30 s, a vacuum time of 15 s and a cooling time of 15 s. PLA/TPS and PLA/TPS/BP-HPBCD thermoformed trays were pale yellow, whereas PLA/TPS/BP-MG thermoformed trays were yellow. Trays from PLA/TPS/BP-MG were easier to form in complete shape than those from PLA/TPS/BP-HPBCD using thermoforming machine. The loss percentage of active compounds in BP of PLA/TPS/BP-MG and PLA/TPS/BP-HPBCD thermoformed trays were determined by Gas Chromatography-Mass Spectrometry (GC-MS). The lowest loss of active compounds in BP were beta-caryophyllene and d-limonene, which lost in thermoforming step from PLA/TPS/BP-MG about 93.30-96.90% and 89.05-89.93%, respectively. Both thermoformed trays from PLA/TPS/BP-HPBCD and PLA/TPS/BP-MG tended to decompose when buried in the soil condition. PLA/TPS/BP-HPBCD and PLA/TPS/BP-MG have been potentially prepared and converted to biodegradable thermoformed trays.