Background Intelligent packaging is the newest technology within the food packaging field. Even though this technology is still growing and not fully commercially viable, it has enormous potential to improve the safety, quality, and traceability of food products, as well as its convenience for consumers. Scope and Approach This paper first describes both the technical aspects and commercial applications of the most representative intelligent technologies-indicators, data carriers, and sensors-with special focus on systems and devices that are directly integrated into the package. Secondly, to provide useful guidelines for future research in the field, the paper discusses some important aspects that still hinder the full exploitation of intelligent technology within the food packaging industry.

A new antifog coating made of pullulan is described in this work. The antifog properties are discussed in terms of wettability, surface chemistry/morphology, and by quantitative assessment of the optical properties (haze and transparency) before and after fog formation. The work also presents the results of antifog tests simulating the typical storage conditions of fresh foods. In these tests, the antifog efficiency of the pullulan coating was compared with that of two commercial antifog films, whereas an untreated low-density polyethylene (LDPE) film was used as a reference. The obtained results revealed that the pullulan coating behaved as a "wetting enhancer", mainly due to the low water contact angle (∼24°), which in turn can be ascribed to the inherent hydrophilic nature of this polysaccharide, as also suggested by the X-ray photoelectron spectroscopy experiments. Unlike the case of untreated LDPE and commercial antifog samples, no discrete water formations (i.e., droplets or stains) were observed on the antifog pullulan coating on refrigeration during testing. Rather, an invisible, continuous and thin layer of water occurred on the biopolymer surface, which was the reason for the unaltered haze and increased transparency, with the layer of water possibly behaving as an antireflection layer. As confirmed by atomic force microscopy analysis, the even deposition of the coating on the plastic substrate compared to the patchy surfacing of the antifog additives in the commercial films is another important factor dictating the best performance of the antifog pullulan coating.

Societal and industrial demands for lower environmental impact, cost effectiveness, and high-performance goods and services are increasingly impacting the choice of technologies which are developed and deployed in consumer products. Like many other sectors, food packaging is moving to new technologies; the use of biopolymers is one of the most promising strategies toward an optimized use of traditional packaging materials (e.g., oil-based plastics) without impairing the goal of extending shelf life. Among other food packaging materials, pullulan is attracting much attention due to its unique features. The goal of this review is to provide an overview of current and emerging applications of pullulan within the food packaging sector. In particular, the functional properties of interest for the food packaging industry will be discussed in light of the physicochemical attributes of this exopolysaccharide. Future challenges that may dictate the successful penetration of pullulan in the food packaging market are also outlined.

The aim of this review is to provide an in-depth overview on the use of inorganic nano-sized entities for the generation of nanocomposite materials in the form of films and coatings for food packaging applications.According to recent trends toward "green" strategies, special focus has been dedicated to the development of nanocomposite coatings obtained using biopolymers as the main polymer matrix. After a first introductive part, the discussion has been addressed to the use of inorganic fillers, metals and metal-oxides, zeolites, and graphene. For each class of filler, a first 'in-depth' description of the most relevant physicochemical properties for the food packaging sector has been followed by case-by-case references to recent developments and envisaged implementations. The technical aspects that may be crucial in the design and end use of (bio)nanocomposite coatings have been covered in the last part of this work, which also includes an updated list of current applications on nano-sized inorganic fillers in the food packaging field.

The aim of this work was to develop and characterize microfibrillated cellulose (MFC)/pullulan bionanocomposites. Fourier transform infrared spectroscopy suggested that the affinity between the two polymers resulted in new hydrogen bonding of the nanocomposite materials compared to pristine pullulan. At the same time, an increase in crystallinity was observed proportional to the amount of MFC used, as shown by the X-ray analyses. Accordingly, final films showed improved mechanical properties proportionally to the filler loading, with impressive elastic modulus and tensile strength of *4.50 GPa and *60 MPa, respectively, for the sample containing 10 % MFC. However, as demonstrated by the moisture sorption isotherms, the addition of MFC did not help reduce the amount of water adsorbed by the samples. In addition, the oxygen and water vapor permeability data clearly showed that final films still suffered high relative humidity values, whereas their barrier performance toward oxygen was excellent under dry conditions, with O 2 permeability coefficients (P 0 O 2 ) comparable with those of common high barrier films/ coatings. Finally, while the nanocomposites in the form of films had high haze values (from 23 to 40 %), the same nanocomposites in the form of coatings were decidedly more transparent, which suggests that their use as thin layers could be more suitable when the ''seethrough'' capability must be preserved, for example in food packaging applications.

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This paper presents the results of an investigation through the design of experiment technique regarding the infl uence of temperature, dwell time and bar pressure on the heat seal strength of oriented polypropylene fi lms coated with a gelatin-based thin layer. This chemometric approach allowed achieving a thorough understanding of the effect of each independent factor on the two different responses (maximum force and strain energy) considered in this work as a measure of the strength necessary to break the bond across the sealed interface. Surprisingly, the factor affecting both responses the most was the bar pressure rather than the sealing temperature. Moreover, whereas the bar pressure negatively affected the seal strength of coated polypropylene fi lms, the sealing temperature had a positive effect. Dwell time did not have any signifi cant infl uence as a main factor, while infl uencing negatively the seal strength as an interaction term (i.e. time × pressure), together with the further interaction temperature × pressure. The mathematical models obtained for the two responses provided different results in terms of fi tting capability (R 2 ) and prediction ability (Q 2 ). In particular, for the maximum force response, R 2 and Q 2 were equal to 0.571 and 0.405, respectively, whereas the model supporting the strain energy response gave R 2 = 0.932 and Q 2 = 0.937, highlighting that for quantifying the seal strength, the energy necessary to break a seal is a better measure than the maximum force. The highest seal strength values obtained during this work were of 0.6615 N and 19.6 N⋅mm for maximum force and strain energy, respectively.

Microfibrillated cellulose (MFC) was used in this study to prepare films containing an active molecule, lysozyme, which is a natural antimicrobial agent. The main goal of this research was to assess the potential for exploiting the nano-sized dimension of cellulose fibrils to slow the release of the antimicrobial molecule, thus avoiding a too-quick release into the surrounding medium, which is a major disadvantage of most release systems. For this purpose, the release kinetics of lysozyme over a 10-day period in two different media (pure water and water/ethanol 10wt.%) were obtained, and the experimental data was fitted with a solution of Fick's second law to quantify the apparent diffusion coefficient (D). The results indicate that the MFC retained lysozyme, presumably due to electrostatic, hydrogen, and ion-dipole interactions, with the largest release of lysozyme-approximately 14%-occurring from the initial amount loaded on the films. As expected, ethanol as a co-solvent slightly decreased the diffusion of lysozyme from the MFC polymer network. The addition of two potential modulating release agents-glycerol and sodium chloride-was also evaluated. Findings from this work suggest that MFC-based films can be considered a suitable candidate for use in controlled-release packaging systems.