Recent Advances in Functional Biopolymer Films with Antimicrobial and Antioxidant Properties for Enhanced Food Packaging

Abstract

Food packaging plays a crucial role in preserving freshness and prolonging shelf life worldwide. However, traditional packaging primarily acts as a passive barrier, providing limited protection against spoilage. Packaged food often deteriorates due to oxidation and microbial growth, reducing its quality over time. Moreover, the majority of commercial packaging relies on petroleum-derived polymers, which add to environmental pollution since they are not biodegradable. Growing concerns over sustainability have driven research into eco-friendly alternatives, particularly natural-based active packaging solutions. Among the various biopolymers, cellulose is the most abundant natural polysaccharide and has gained attention for its biodegradability, non-toxicity, and compatibility with biological systems. These qualities make it a strong candidate for developing sustainable packaging materials. However, pure cellulose films have limitations, as they lack antimicrobial and antioxidant properties, reducing their ability to actively preserve food. To tackle this issue, researchers have created cellulose-based active packaging films by integrating bioactive agents with antimicrobial and antioxidant properties. Recent innovations emphasize improving these films through the incorporation of natural extracts, polyphenols, nanoparticles, and microparticles. These enhancements strengthen their protective functions, leading to more effective food preservation. The films are generally classified into two types: (i) blend films, where soluble antimicrobial and antioxidant substances like plant extracts and polyphenols are incorporated into the cellulose solution, and (ii) composite films, which embed nano- or micro-sized bioactive fillers within the cellulose structure. The addition of these functional components enhances the antimicrobial and antioxidant efficiency of the films while also affecting properties like water resistance, vapor permeability, and mechanical strength. The continuous progress in cellulose-based active packaging highlights its potential as a viable alternative to conventional materials. These innovative films not only extend food shelf life but also contribute to environmental sustainability by reducing reliance on synthetic polymers. This review deals with the development of functional biopolymer films with antimicrobial and antioxidant properties towards sustainable food packaging.

Keywords: bio-active fillers; cellulose; functional biopolymers; sustainable food packaging.

Figure 1

Schematic representation of the modified cellulose/curcumin film (MRC) fabrication through a two-step process: curcumin incorporation into the cellulose matrix, followed by organosilane-based hydrophobic modification. Mechanical flexibility of MRC15, including bending, folding, twisting, and knotting. Performance comparison of PE, PBAT, PLA, and MRC15. SEM images of RC0, RC15, MRC0, and MRC15 [57].

Figure 2

Film color variations in response to fish filets over time (a). TVB-N value fluctuations during fish filet storage (b). Relationship between TVB-N levels and color shift (ΔS) (c) [57].

Figure 3

Relative viability of L929 cells after 24 h co-incubation with nanofibrous films: (A) CMCH/PCL, (B) CUR/CMCH/PCL, (C) NAT/CMCH/PCL, (D) NIS/CMCH/PCL, and (E) THY/CMCH/PCL. (F) Fluorescence imaging of cells, where live cells (Calcium-AM) emit green fluorescence, and dead cells (PI) appear red [59]. * and ** indicate statistical significance.

Figure 4

(A) Cherry tomatoes infected with Botrytis cinerea and covered with an in situ packaging coating. (B) Cherry tomatoes after the removal of the coating. (C) Measurement of lesion diameters. Scale bar: 3 cm [59]. ** and *** indicate statistical significance.

Figure 5

Schematic illustration of the film fabrication process [62].

Figure 6

(A) (a) Indicator films used for shrimp freshness monitoring, (b) color variation analysis, and (c) TVBN value changes over different storage durations. Scale bar: 3 cm. (B) Antibacterial activity of films against E. coli and L. monocytogenes: P (a) and PM20C (b) [P = PLA:TPS (100:0) PLA (polylactic acid) and TPS (thermoplastic starch), PC = PLA:TPS (100:0) with the addition of cochineal (0.5 Phr), P20C = PLA:TPS (80:20) with the addition of cochineal (0.5 Phr) and PM20C = same composition as P20C, ‘M’ indicates the premodification of TPS with citric acid and cochineal before added to PLA] [62].

Figure 7

Schematic illustration of CNF/CMC-coated MP tray fabrication process [5].

Figure 8

Images of raspberries, blueberries, and cherry tomatoes (left to right) used in shelf-life testing with PLA as the lidding film. Within each set, the samples from left to right are as follows: uncoated without a lid (control), uncoated with a lid, and coated with a lid [5].

Figure 9

(a) Schematic illustration of the fabrication process for CMC-based hydrogel film. (b) FTIR and (c) XRD spectra of CMC/PVA, CMC/PVA/PEI, and CMC/PVA/PEI/TA. (d) Suggested dynamic reversible non-covalent interactions among polymers. (e) Amidation reaction between PEI and protonated CMC [68].

Figure 10

Changes in the visual appearance of strawberries and cherries over the storage period [60].

Figure 11

Preparation process of CSCs [33].

Figure 12

(A) (a) Comparison of samples used for packing oranges. (b) Retention of quality in oranges. (c) Shrinkage in volume of oranges. (B) (a) Water absorption and barrier properties against water/water vapor. (b) Potential water molecule penetration routes. (c) Water contact angle measurements for CSC-0, CSC-1, CSC-2, and CSC-3 films. (d) Antibacterial activity against S. aureus and E. coli. (e) Simulation results for CSCs in fruit packaging [33].

Figure 13

Different methods to fabricate the chitosan-based films [73].

Figure 14

Comparison of uncoated bananas (1) and bananas coated with CMC100 film (2), HTCC40/CMC60 film (3), HTCC70/CMC30 film (4), HTCC90/CMC10 film (5), and HTCC100 film (6). CMC refers to carboxymethyl cellulose, and HTCC refers to 2-N-hydroxypropyl-3-trimethylammonium chloride chitosan. The application of the sensing film as a freshness indicator for pork and fish [73].

Figure 15

(a) Fabrication process of pectin–glycerol (PG) films. (b) Schematic and (c) mechanism illustrations showing glycerol’s plasticizing effect in PG films. Digital images of (d) PG film without glycerol (PG-0) and (e) PG film with 50% glycerol relative to pectin content (PG-50). (f,g) Atomic force microscopy images of the surface of (f) PG-0 and (g) PG-50 films [76].

Figure 16

(a) Voltage output of pectin–glycerol film-based triboelectric nanogenerators (P-TENGs), where one triboelectric layer is PG-50 (pectin–glycerol film with 50% glycerol by weight), after water absorption and desorption at varying relative humidity (RH) levels. Asterisks denote significant differences in voltage outputs between the water-sorption and water-desorption processes at specific RH values (p < 0.05). (b) Operating principle of a P-TENG used as a humidity sensor. (c) Changes in cracker quality when stored at low vs. high RH. (d) Dry-basis moisture content of crackers stored at different RH levels. Black: water sorption; red: water desorption. (e) Hardness variation in crackers stored at different RH levels. Purple: water sorption; blue: water desorption [76].

Figure 17

Preparation and fabrication route of CEO/CS@PLA MB [79].

Figure 18

Variation in colony count of E. coli and S. aureus on PLA MB, CS@PLA MB, and CEO/CS@PLA MB with different CEO concentrations. Visual appearance of strawberries from three groups stored at (a) 4 ± 1 °C and (b) 25 ± 3 °C [79].

Figure 19

Schematic of flexible nanoporous polycaprolactone-based (FNP) films for active food packaging: (a) (i) Overview of study approaches and strategies; (ii) design of packaging systems, including open and closed PET (control), flexible flat PCL (FF), and FNP-based packaging for preserving cherry tomatoes, tangerines, and bananas. (b) FNP film fabrication via O₂ plasma modification of FF films. (c,d) FE-SEM images of FF (c) and FNP (d) film surfaces. (e) XPS scans of FF and FNP films. (f,g) High-resolution O1s XPS spectra of FF (f) and FNP (g) films [82].

Figure 20

Impact of flexible nanoporous polycaprolactone (FNP) film on the storage quality of tangerines: (a,b) Mold growth on tangerines stored at 25 °C (a) and 4 °C (b) for 17 days. (c,d) Tangerine weight loss at 25 °C (c) and 4 °C (d) over 17 days. (e) Firmness of tangerines stored at 25 °C for 17 days. (f) Total soluble solid (TSS) content (°Brix) of tangerines stored at 25 °C for 17 days [82]. * indicate statistical significance.