Bio-based materials will eventually have to replace all petroleum-based materials in food packaging. A blend of starch and other polymers provides an equally efficient protective barrier, according to research conducted at Karlstad University. “Food packaging must safeguard and extend the shelf life of food, as well as function during transportation. A protective barrier in paper-based packaging, such as that used for juice or dairy, is required to meet these demands,” explains Asif Javed.
A coating is required on paper-based food packaging to prevent water or oxygen from penetrating the packaging and spoiling the contents. Typically, a petroleum-based plastic is used to provide this protective layer. Researchers have been looking for a good bio-based material to replace fossil-based raw materials for decades. They found that a mixture of lignin from wood and starch from potatoes or maize could potentially perform this function just as well as plastic.
As packaging materials, starch films can be a great alternative to non-degradable traditional plastic films. Aside from relevant features such as mechanical or barrier capabilities, packaging material should also have good printability to convey some required product information. The film’s tensile strength, water vapour transition rate, and moisture content were measured and compared to those found in the literature. Based on research conducted by Żołek-Tryznowska and Holica, starch film has a lot of potential as biodegradable, environmentally friendly packaging materials. It is also naturally degrading without leaving behind dangerous microplastics, should it end up in forests, lakes or oceans.
The use of renewable biomass and environmentally friendly materials is becoming popular in research and development around the world. Researchers are considering starch as one of the most abundant and affordable alternatives to petroleum products. Extending the usage of starch construction techniques and combining this material with other materials to mitigate the inherent shortcomings of this natural polymer has resulted in its continued development in a variety of industries, particularly the packaging industry. The production and usage of starch as a raw material is predicted to grow in importance across a wide range of industries. Because each source of starch has its own set of features, many sources of starch have been researched for bio-films in the food packaging business such as Corn Starch and Tapioca Starch. It produces films with unique features and avoids the use of harmful chemicals during production. Another innovative technique to enhancing mechanical properties and starch permeability is to use various polymers with starch in the film process. This has the most impact on the mechanical properties of starch-based films, but it may also have other properties, such as antibacterial properties. The usage of bio-nano-composites in many unique investigations on starch composite films can have a positive impact on the properties of these films.
In order to alleviate the existing environmental concerns created by conventional plastics while improving the sustainability of industrial operations, it has become vital to use biodegradable materials from renewable sources for food packaging. Bioplastics’ competitiveness in terms of characteristics and cost, however, needs to be enhanced. Although petroleum-derived plastics have strong mechanical qualities and low water vapor sensitivity and permeability, they have weak oxygen barrier capacity in some situations, which is a considerable advantage for food packing.
Starch materials have a good location on the barrier properties map in terms of oxygen permeability, but they are far from water barrier requirements, and, worse, their high water uptake capacity causes an increase in WVP (and also oxygen permeability) in response to moisture gain and polymer matrix plasticization. Similarly, starch-based materials’ mechanical qualities are highly susceptible to moisture and ageing due to starch retrogradation, which is aided by molecular mobility associated with water uptake. Starch materials’ strong water sensitivity limits their industrial applicability, despite their low oxygen permeability. As a result, it’s critical to change these materials to boost their hydrophobicity and make them easier to utilize, taking advantage of starch’s widespread availability and inexpensive cost.
Learn more about the exciting potential and advancements in the future of starch-based materials in food packaging.