usages of such polymers have created immense negative impact in the atmosphere,
because of their toxic nature after incineration, non-biodegradability and pollution of
water bodies [1].
1.1 Global Production and Impact
The demand for polymers in food packaging applications has been constantly on the
rise owing to the increase in consumption of convenience foods. Global trades in
processed foods have reached more than two trillion US dollars, and packaged foods
contribute for half the quantity of that. When compared with other packaging
materials like metal, paper, and board, plastic packaging occupies a major share of
it (40%) [2]. The packaging materials employed in food industries have very short
lifetime, cannot always be recycled, and after their utilization, majority of them
accumulate in the landfills and water bodies, causing serious ecological concerns. It
has been identified that only less than 3% of the plastic bags (500 billion) that are
distributed in the market every year are recycled [3]. The plastic packaging materials
used are frequently contaminated by biological substances and by foodstuff, thereby
making it complicated for recycling process.
A feasible way to solve this issue is to replace non-natural polymers with
eco-friendly materials particularly for packaging applications. However there are
stiff challenges faced in using biodegradable polymers owing to their processability,
cost, and functional properties when compared with synthetic polymers. The biodegradable polymers can be produced by utilizing natural resources like plants,
animals, and microorganisms or from other renewable resources and are degraded
by the enzymatic action of fungi, yeast, and bacteria; and they are compostable by
acting as fertilizers and soil conditioner. Some of the important examples are
polylactic acid, cellulose, starch, chitosan, lignin, and proteins [4].
2 Classification of Bioplastics
The bioplastics are categorized into four sections depending on their method of
synthesis, source, and chemical composition.
Based on their chemical composition, source, and synthesis method, bioplastics
can be classified into four categories (shown in Fig. 1): (1) polymers derived
straightly from biomass (e.g., protein, starch, cellulose); (2) polymers produced
through chemical synthesis by utilizing bioderived monomers (e.g., bio PE, PHB,
PLA); (3) polymers produced from microbial fermentation (e.g.,
polyhydroxyalkanoates); and (4) polymers produced through chemical synthesis
by utilization of both petroleum-based and bio-derived monomers (e.g., PTT,
PBS) [6].
Bioplastics made out of starch, cellulose, PLA, and PHAs have gained commercial importance in recent times, due to their ease in processing using existing
Recent Developments in Food-Based Bioplastics Production
109
because of their toxic nature after incineration, non-biodegradability and pollution of
water bodies [1].
1.1 Global Production and Impact
The demand for polymers in food packaging applications has been constantly on the
rise owing to the increase in consumption of convenience foods. Global trades in
processed foods have reached more than two trillion US dollars, and packaged foods
contribute for half the quantity of that. When compared with other packaging
materials like metal, paper, and board, plastic packaging occupies a major share of
it (40%) [2]. The packaging materials employed in food industries have very short
lifetime, cannot always be recycled, and after their utilization, majority of them
accumulate in the landfills and water bodies, causing serious ecological concerns. It
has been identified that only less than 3% of the plastic bags (500 billion) that are
distributed in the market every year are recycled [3]. The plastic packaging materials
used are frequently contaminated by biological substances and by foodstuff, thereby
making it complicated for recycling process.
A feasible way to solve this issue is to replace non-natural polymers with
eco-friendly materials particularly for packaging applications. However there are
stiff challenges faced in using biodegradable polymers owing to their processability,
cost, and functional properties when compared with synthetic polymers. The biodegradable polymers can be produced by utilizing natural resources like plants,
animals, and microorganisms or from other renewable resources and are degraded
by the enzymatic action of fungi, yeast, and bacteria; and they are compostable by
acting as fertilizers and soil conditioner. Some of the important examples are
polylactic acid, cellulose, starch, chitosan, lignin, and proteins [4].
2 Classification of Bioplastics
The bioplastics are categorized into four sections depending on their method of
synthesis, source, and chemical composition.
Based on their chemical composition, source, and synthesis method, bioplastics
can be classified into four categories (shown in Fig. 1): (1) polymers derived
straightly from biomass (e.g., protein, starch, cellulose); (2) polymers produced
through chemical synthesis by utilizing bioderived monomers (e.g., bio PE, PHB,
PLA); (3) polymers produced from microbial fermentation (e.g.,
polyhydroxyalkanoates); and (4) polymers produced through chemical synthesis
by utilization of both petroleum-based and bio-derived monomers (e.g., PTT,
PBS) [6].
Bioplastics made out of starch, cellulose, PLA, and PHAs have gained commercial importance in recent times, due to their ease in processing using existing
Recent Developments in Food-Based Bioplastics Production
109