We conducted a literature search on Google scholar using keyword combinations like active packaging fruit polyphenols, fruit waste polyphenols, vegetable polyphenols, and vegetable waste polyphenols. Then, high-quality and highly cited research articles on active food packaging materials using natural polyphenols were selected and used in this review.

We excluded conference abstracts, review articles, and non-English peer-reviewed publications as well as non-indexed, off-quality, and bad articles from our review.

Intelligent food packaging is a subset of smart packaging that focuses on sensing and measuring attributes related to the real-time conditions of packed food items rather than direct interactions with the food; it does not alter the condition of the food and offers vital information to both consumers and stakeholders. Intelligent packaging often features time–temperature indicators, freshness sensors, and radio frequency identification (RFID) tags that communicate the product history and quality status (Figure 1). Similar to smart food packaging, intelligent food packaging utilizes the advantages of naturally sourced polyphenols as active ingredients to achieve antimicrobial, antioxidant, and antibrowning properties as well as prolonged shelf life of the food (Kanatt, 2020; Vilas et al., 2020; Sarfraz et al., 2024).

Catechins are the primary polyphenols in tea and comprise gallocatechins, gallocatechin gallate, epigallocatechin-3-gallate (EGCG), epicatechin-3-gallate, and epicatechin (Figure 2). However, EGCG is the most extensively researched catechin of green tea (Khan and Mukhtar, 2018). The active food packaging films prepared using tea polyphenols are mostly sourced commercially as high-purity tea polyphenols (Supplementary Table S1). The active packaging films/pads prepared using tea polyphenols have improved properties, such as UV-barrier property, water-vapor barrier property, tensile strength, surface hydrophobicity, roughness, and gas-barrier property. Nonetheless, some properties of the polyphenol-based active packaging films are diminished, such as the elongation at break, water vapor permeability (WVP), swelling degree, and optical transmittance (Supplementary Table S2). Solution casting is the most widely used method to prepare polyphenol-based active packaging films; however, electrospinning, temperature-assisted electrospinning, and ultrasound-assisted solution casting methods are also reported for the preparation of tea-polyphenol-based active films (Supplementary Table S3). The antioxidant properties of these polyphenol-based active packaging films have been evaluated using ABTS, DPPH, and FRAP assays, whereas the ager disk diffusion assay and CFU count of viable microorganisms have been used to assess the antimicrobial properties. Furthermore, food-infection-associated microorganisms have been used for such antimicrobial tests (Supplementary Table S3), such as Listeria monocytogenes (NCTC 7973) and Escherichia coli (NCTC 9001); Staphylococcus aureus (ATCC 29215) and E. coli (ATCC 25922); S. aureus (ATCC 6538), E. coli (PTCC 1330), and Staphylococcus aurous (PTCC 1112) (Siripatrawan and Harte, 2010; Ashrafi et al., 2018; Chenwei et al., 2018; Biao et al., 2019; Chen et al., 2019; Wu et al., 2019; Yuan et al., 2020; Yang et al., 2021; Zhang et al., 2021; Miao et al., 2022; Zhou et al., 2022). Lastly, it has been recognized that the catechins from green tea possess antioxidant, anticancer, and cardiovascular disease preventive properties (Mandel et al., 2006; Tsai and Chen, 2016).

Natural polyphenols are excellent alternatives to synthetic food additives and also help in minimizing the adverse environmental impacts of industrial byproducts by recovering useful bioactive polyphenols from agricultural and food wastes (Mourtzinos and Goula, 2019). Active packaging films prepared using fruit polyphenols are often sourced from black currants, murta fruit, calanda peach, young apples, Chilean berries, goji berries, mastic leaves, olive fruits, citrus fruits, lychees, mulberries, wolf berries, myrtle berries, red raspberries, pomegranates, Chinese hawthorn, and κ-carrageenan mulberries. However, fruit-waste polyphenols are often sourced from apple peels, pecan nut shells, shallot wastes, pomegranate peels, apple pomace, mango peels, rambutan peels, litchi pericarps, grape pomace, pomelo and lime peels, and coconut water, among others (Supplementary Table S4). However, most of these studies have reported the advantages of the total phenolic contents of fruit polyphenols (Supplementary Table S1). A few reports have analyzed the total phenolic content using different sophisticated analytical techniques, including high-performance liquid chromatography with and without diode array detection, gas chromatography mass spectrometry, and tandem mass spectrometry. Furthermore, the different polyphenols obtained from vegetables, leaves, and spices used in active food packaging are sourced from cinnamon leaves, cinnamon oil, drumstick, papaya, Malaysian herbs, natural phenolic compounds, natural antioxidants, curcumin, soybean husk, and spent coffee ground extracts, among others (Supplementary Table S5). Positive antioxidant, antimicrobial, and antibrowning properties have been linked with extended shelf lives of packed food products. Notably, active packaging films prepared using polyphenols from fruits, fruit wastes, vegetables, and leaves have demonstrated positive antioxidant, antimicrobial, and antibrowning properties, thereby contributing to extended shelf lives of packed foods (Section 6.4).

Oxidative damage is one of the leading causes of quality degradation of packaged foods, mainly because the ambient oxygen oxidizes the lipids within the food. Even at low concentrations, lipid oxidation produces various non-volatile and volatile chemicals that are sufficient for reducing or removing the organoleptic properties of food (Velasco et al., 2010). There are many ways in which the lipid content in foods can be oxidized, such as autoxidation, hydroperoxide formation, hydroperoxide decomposition, enzymatic oxidation, and photo-oxidation (Figure 3). In addition, the main factors influencing lipid oxidation are oxygen content or availability, storage temperature, light permeability, fatty acid composition, metals, physical structure of the food, and antioxidants (Velasco et al., 2010). Antioxidant active packaging offers excellent protective properties against oxidative damage of the food (Siripatrawan and Harte, 2010; Kan et al., 2019; Zhang et al., 2021); in addition, slow release of the antioxidant compounds from the active packaging films/pads can help extend the shelf lives of packed foods (Section 6.4). Notably, the majority of the active packaging studies concerning polyphenols have reported the antioxidant properties of active packaging films or pads (Supplementary Tables S2–S5); sensitive biochemical assays like DPPH, ABTS, and FRAP have been performed to assess the antioxidant properties of these active packaging films/pads to confirm reliability. Light permeability, O₂ barrier property, and the shape of the packaged food are also some of the major factors influencing oxidative deterioration of food (Velasco et al., 2010); notably, these properties of active packaging films were also reported to positively improve in favor of reducing the oxidative damage of foods such as fresh-cut apples and vegetables (Supplementary Tables S2–S5).

The antimicrobial properties of natural polyphenols are well-known (Chollakup et al., 2020), and tea polyphenols are very popular for their antimicrobial properties (Chenwei et al., 2018; Riaz et al., 2018; Wu et al., 2019; Yang et al., 2021; Sharma et al., 2022; Vieira et al., 2022; Zhou et al., 2022). Resistance to microbial growth is also an important property of natural-polyphenol-based active packaging films as it is positively correlated with extended shelf life of the packaged food (Section 6.4). Natural polyphenols, including the polyphenols from tea, fruits, and vegetables, noted herein have been reported to demonstrate antimicrobial properties (Supplementary Tables S2–S5). As noted before, most of the studies on active food packaging have reported mainly the total polyphenolic content (Supplementary Tables S2–S5), while very few studies have reported the active components in the total phenolic content, such as EGCG, catechins, caffeine, tannic acid, gallic acid, bromelain, and ferulic acid (Supplementary Table S1). In general, there are five modes of action for antimicrobial compounds (Figure 4), namely by interfering with cell wall synthesis, plasma membrane integrity, nucleic acids, ribosomes, and folate biosynthesis (Neu and Gootz, 1996). The exact molecular mechanisms of the polyphenolic compounds have not been explored or discussed in extant studies on active food packaging using natural and food-waste polyphenols. However, the antimicrobial action modes of fruit polyphenols have been discussed extensively in an excellent review article by Kumar et al. (2021).

Fruit polyphenols may exert antimicrobial effects by inactivation of lipopolysaccharides (LPSs) (proanthocyanidins), antiadhesion (myricetin and proanthocyanidins), chelation of metal ions (tannic acid), inhibition of amino acid synthesis (gallic acid and caffeic acid), inhibition of binding (proanthocyanidins), disintegration of membrane proteins (bromelain), repression of genes (phloretin), ionic imbalance (p-coumaric acid, ferulic acid), inhibition of enzyme activities (phenolic compounds and catechins), pore formation in the cell membrane (p-coumaric acid and ferulic acid), and cytoplasmic leakage (bromelain). Nonetheless, the action modes of natural and food-waste polyphenols like gallic acid, caffeic acid, and tannic acid may be inferred from previous studies (Kumar et al., 2021). These antimicrobial studies were evaluated using agar plate disk diffusion assays and colony-forming unit (CFU) counts of viable bacteria (Supplementary Tables S2–S5), while food-infection-associated microorganisms like Bacillus cereus, L. monocytogenes, E. coli, and S. aureus were used to confirm the antimicrobial properties (Supplementary Tables S2–S5). However, active packaging studies have demonstrated the antibacterial activities of natural polyphenols without using any standard antimicrobial substances as quality controls; hence, it may be necessary to include one or two positive controls while studying the antimicrobial properties of such polyphenols.

Fruits and vegetables are commonly affected by enzymatic browning (Hamdan et al., 2022). Melanins are the compounds responsible for such browning (Djafarou et al., 2023) and are generated by the oxidation of phenolic compounds in damaged, sliced, peeled, and diseased fruits and vegetables. Melanins also cause the fruits and vegetables to darken faster when exposed to air. Enzymatic browning is primarily caused by polyphenol oxidase (PPO), while tyrosinase is responsible for melanin production (Djafarou et al., 2023) in most fruits, vegetables, and certain seafoods. Along with PPO (Moon et al., 2020), the related oxidative enzyme peroxidase may cause enzymatic browning of fruits and vegetables (Jiang et al., 2016). Active packaging films prepared using shallot waste extracts show excellent antibrowning effects against fresh-cut apples and potatoes through disruption of oxygen permeability, thereby facilitating longer storage (Thivya et al., 2021). Active packaging films prepared using shallot waste extracts were shown to accumulate CO₂ inside the packaging, while O₂ was consumed during respiration because of the O₂ barrier property of the film (Thivya et al., 2021). Conversely, fresh-cut fruits and vegetables packed with conventional plastic packaging films accumulate water and CO₂ inside the package, resulting in spoilage of the packaged food probably due to active anerobic respiration (González et al., 2008). There are two possible approaches to inhibit the browning of fresh-cut fruits and vegetables, namely, by inhibition of oxygen permeability and addition of antioxidant substances (Arrieta et al., 2020). Nonetheless, poor WVP and gas barrier properties of the packaging films may contribute to browning of foods (Figure 5). Active packaging films prepared using antioxidant extracts from the African horned melon (Cucumis metuliferus) have demonstrated excellent antibrowning effects by inhibiting the primary enzyme PPO (Arrieta et al., 2020). Moreover, as noted previously, tyrosinase is a member of the PPO family and is also very important for oxidative degradation of food items, especially fruits and vegetables (Loizzo et al., 2012). Remarkably, pecan nut shell hydroalcoholic extracts were recently reported to possess the ability to inhibit mushroom tyrosinase (Moccia et al., 2020).

The shelf life of a food is the amount of time that the food is expected to be safe for eating and have intact organoleptic properties; it is primarily determined by four important aspects of food, namely, the formulation, processing, packaging, and storage conditions (Gallagher et al., 2011). WVP is a measure of the ease with which water vapor can move through a substance and is one of the main factors influencing high-quality food packaging and storage because water is crucial to spoiling reactions (Cazón et al., 2022). Thus, WVP plays a significant role in extending the shelf life of packaged foods (Kanatt et al., 2012). Active packaging films prepared using polyphenols from Chinese hawthorn (Crataegus pinnatifida) show excellent WVP, which may also help in extending the shelf lives of foods (Kan et al., 2019). Moreover, food packaging materials with better gas barrier (mainly O₂), added antioxidant, and antimicrobial properties could promote extension of the shelf lives of foods. The effectiveness and quality of active packaging films in preventing microbial attacks on food are also linked to extending their shelf lives (Hanani et al., 2018). For example, the shelf lives of fresh-cut apples were shown to increase upon packaging them inside active films made of chitosan lychee pericarp powder (CHS-LPP). This may be attributed to the superior gas barrier and WVP properties, which inhibit O₂ and water from the outside environment into foods packed within the CHS-LPP films. Furthermore, CHS-LPP films are economically viable and environmentally friendly options as they are made from waste materials. CHS-LPP films were shown to exhibit excellent antioxidant properties and were successful in preventing oxidative degeneration of food, suggesting that they may also help in prolonging the shelf lives of foods by preventing oxidative degeneration (Jiang et al., 2021). Other films made of plasma-treated zein, pomegranate peel, and chitosan nanoparticle nanocomposites have been shown to be effective in reducing bacterial growth and prolonging the shelf lives of packed pork meat until the end of the prescribed storage period (Cui et al., 2020). Similarly, chitosan (CS) apple peel polyphenol (CS-APP) film was shown to improve WVP; mild changes in the mechanical characteristics of CS-APP films at low polyphenol concentrations suggest that they could be suitable substitutes for synthetic materials. The combined effects from CS and APP are also known to have antibacterial properties; thus, CS-APP films may be used as antimicrobial packaging materials to extend the shelf lives of foods (Riaz et al., 2018). The shelf lives of chicken samples packaged within curcumin with active films made of chitin and glucan complexes (CGCs) were significantly extended compared to control samples as the CGC active films demonstrate excellent capacity to inhibit viable counts of bacteria; thus, positive antimicrobial properties may improve the shelf lives of meat products (Kaya et al., 2022). Moreover, CGC active films are biodegradable, suggesting that they are sustainable and environment friendly. Slow emission of the active ingredients in active packaging films is another aspect that may help with extending the shelf lives of food products (Amjadi et al., 2019).

An active compound can be applied as a surface coating to function at the surface level, which permits the use of active compounds at any point in the food supply chain (Arrieta et al., 2020). Therefore, to achieve prolonged shelf lives of food products, active compounds such as antioxidants and antibacterial agents may be applied to the surfaces of the packing materials. Furthermore, active packaging films containing fish gelatin and pomegranate peel powder have shown excellent antibacterial and antioxidant capabilities. The strongest protection against food pathogens during storage may be achieved through the active ingredients in the packaging materials, which could help in extending the shelf lives and maintaining the quality of foods (Hanani et al., 2019). Young apple polyphenol chitosan films have demonstrated antibacterial and antimold properties and may thus be useful as antimicrobial packaging materials to increase shelf lives of foods (Sun et al., 2017). Active packaging with edible-polyphenol-enriched plant extracts containing coatings could allow extension of the shelf lives of food products mainly because the ingredients are of natural origin and through the bioactive properties of the phytochemicals (Montero-Prado et al., 2011). In summary, the shelf lives of food products could be extended through several attributes of active packaging films, such as antimicrobial properties (antiviral, antimold, and antifungal), antioxidant properties, lower WVP, reduced O₂/gas permeability, light barrier properties, and slow release of active polyphenols (Figure 6). Notably, active packaging films prepared using natural and food-waste polyphenols show these important properties, suggesting that these films may be useful for better food preservation.

The polyphenols found in fruits and plants are considered highly important functional foods. Thus, the use of polyphenols from fruit and food wastes may also have health-promoting properties alongside sustainability. To date, several in vitro and in vivo studies have been conducted to evaluate the effects of these chemicals on health (Agarwal et al., 2013; Afrin et al., 2016; Rana et al., 2022). Herein, we describe the anti-inflammatory, antihypertensive, and antidiabetic actions of polyphenols as well as their antioxidant and anticytotoxic capacities based on experimental evidence (Figure 7). Research has shown that polyphenols serve important roles in protecting the body from external stimuli and eliminating reactive oxygen species, which are responsible for several illnesses (Abolaji et al., 2018). Tea, chocolate, fruits, and vegetables contain polyphenols, which have the potential to boost the health of the human cardiovascular system positively. For example, the flavan-3-ols of cocoa have been associated with decreased risk of myocardial infarction, stroke, and type 2 diabetes in both animal and human studies. Additionally, resveratrol as a flavonoid and stilbene has been linked to a healthier heart (Abolaji et al., 2018; Lüscher, 2021). In addition to improving blood pressure, lipid profile, and insulin resistance, diets high in polyphenols can also lower cholesterol levels. Polyphenols from dietary sources may exert therapeutic effects on the gut microbiome through multifactorial characteristics. There is an increasing body of evidence on how the human gut microbiome intercedes feedback between our diet and health; the gut microbiome is also an important mediator of gut and systemic inflammation (Singh et al., 2017). It is important to note that polyphenols are converted into bioactive compounds by the gut microbiome. Expanding on this point, research on aging and longevity support the notion that the gut microbiome is at the core of many age-related disorders, including immune system dysregulation and susceptibility to major diseases (Badal et al., 2020). Recent studies have suggested that the intestinal microbiome has vital influence on modulating susceptibility to several chronic and common diseases, including inflammatory bowel disease, obesity, type 2 diabetes, cardiovascular diseases, and cancer.