Innovations in starch-based film technology

Edible and biodegradable films can offer great potential to enhance food quality, safety and stability. The unique advantages of edible films and coatings may lead to new product developments, such as individual packaging of particulate foods, carriers for different additives, and nutrient supplements (Vermeiren et al., 1999). Composite films can be formulated to combine the advantages of each component. Proteins and polysaccharides provide the supporting matrix and are good barriers to gases, while lipids provide a good barrier to water vapor (Krochta and De Mulder Johnston, 1997). Over the last few years, there has been a renewed interest in biodegradable films and films made from renewable and natural polymers such as starch (Lawton, 1996; Vicentini et al., 2005). Several studies have been done to analyze the properties of starch-based films (Lawton and Fanta, 1994; Lourdin et al., 1995; Arvanitoyannis et al., 1998; Garcia et al., 1998a, 1998b, 2000a, 2000b, 2001; Mali et al., 2002; Vicentini et al., 2005). The use of a biopolymer such as starch can be an interesting solution because this polymer is quite cheap, abundant, biodegradable and edible. Amylose is responsible for the film-forming capacity of the starches. Starches are polymers that naturally occur in a variety of botanical sources such as wheat, corn, potatoes and tapioca or cassava. It is a renewable resource widely available and can be obtained from different by-products of harvesting and raw material industrialization.