Phytochemical profiles of lemon verbena (Lippia citriodora H.B.K.) and its potential application to cookie enrichment

In this research, phytochemical properties of lemon verbena and oxidative stability of the fat component in cookies (contain lemon verbena powder and EO) were investigated. The essential oil (EO) profile and polyphenol compounds were identified by GC/MS and HPLC, respectively. Different concentrations of lemon verbena powder and EO were added to the cookies in comparison with TBHQ. The oxidative stability of fat component in cookies (peroxide value, p-Anisidine, TOTOX value), along with the physicochemical (pH, acidity, weight loss, and moisture content) and sensory properties of the cookies were evaluated over a period of 6 months during storage at room temperature. The main constituents of EO are geranial (27.21%), neral (20.01%), spathulenol (7.28%), and limonene, while trans-Ferulic acid (6.71 mg/g), Hesperidin (1.87 mg/g), and ρ-Coumaric acid (0.04 mg/g) were measured as main phenolic compounds. The peroxide value increased in all samples for the first 2 months of storage and then decreased as hydroperoxide was converted to secondary oxidation products. The p-Anisidine value increased in all samples during storage. This parameter was lower in cookies containing lemon verbena EO and TBHQ treatments. Sensory evaluations of cookies showed that lemon verbena EO had positive effects on the aroma and taste of cookies during storage, whereas lemon verbena powder had adverse effects on mouthfeel and consumer acceptance. The results showed that lemon verbena can increase the eating quality, prolong the shelf life, and maintain the integrity of bakery products with high-fat content.

High-Oxygen-Barrier Multilayer Films Based on Polyhydroxyalkanoates and Cellulose Nanocrystals

This study reports on the development and characterization of organic recyclable high-oxygen-barrier multilayer films based on different commercial polyhydroxyalkanoate (PHA) materials, including a blend with commercial poly(butylene adipate-co-terephthalate) (PBAT), which contained an inner layer of cellulose nanocrystals (CNCs) and an electrospun hot-tack adhesive layer of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) derived from cheese whey (CW). As a result, the full multilayer structures were made from bio-based and/or compostable materials. A characterization of the produced films was carried out in terms of morphological, optical, mechanical, and barrier properties with respect to water vapor, limonene, and oxygen. Results indicate that the multilayer films exhibited a good interlayer adhesion and contact transparency. The stiffness of the multilayers was generally improved upon incorporation of the CNC interlayer, whereas the enhanced elasticity of the blend was reduced to some extent in the multilayer with CNCs, but this was still much higher than for the neat PHAs. In terms of barrier properties, it was found that 1 µm of the CNC interlayer was able to reduce the oxygen permeance between 71% and 86%, while retaining the moisture and aroma barrier of the control materials.

Biodegradable Chitosan Films with ZnO Nanoparticles Synthesized Using Food Industry By-Products—Production and Characterization

This work aimed to produce bionanocomposites of chitosan incorporated with zinc oxide nanoparticles (ZnO NPs) synthesized using food industry by-products and to characterize them. Such nanoparticles are highlighted due to their low cost, antimicrobial activity, accessibility, and sustainability synthesis. Four different levels of ZnO NPs (0, 0.5, 1.0, and 2.0% w/w of chitosan) were tested, and the bionanocomposites were characterized in terms of their hydrophobicity, mechanical, optical, and barrier properties. Overall, the incorporation of ZnO NPs changed the composites from brittle to ductile, with enhanced elongation at break and reduced Young Modulus and tensile strength. Thus, ZnO NPs acted as plasticizer, turning the films more flexible, due to the presence of organic compounds on the NPs. This also favored permeability of oxygen and of water vapor, but the good barrier properties were maintained. Optical properties did not change statistically with the ZnO NPs incorporation. Thus, the characterization presented in this paper may contribute to support a decision on the choice of the material’s final application.

Two Fascinating Polysaccharides: Chitosan and Starch. Some Prominent Characterizations for Applying as Eco-Friendly Food Packaging and Pollutant Remover in Aqueous Medium. Progress in Recent Years: A Review

The call to use biodegradable, eco-friendly materials is urgent. The use of biopolymers as a replacement for the classic petroleum-based materials is increasing. Chitosan and starch have been widely studied with this purpose: to be part of this replacement. The importance of proper physical characterization of these biopolymers is essential for the intended application. This review focuses on characterizations of chitosan and starch, approximately from 2017 to date, in one of their most-used applications: food packaging for chitosan and as an adsorbent agent of pollutants in aqueous medium for starch.

Free Radical Scavenging Activity of Some Legumes Hulls Extract and Its Efficacy on Oil Oxidative Stability

BACKGROUND

Synthetic antioxidants have toxigenic effects, there is therefore growing interest in substituting them with natural antioxidants. Attention is being focused on extracting them from agricultural industry residuals to minimize costs. Legume seed hulls could be cheap sources of such natural antioxidants.

OBJECTIVE

This study aims to unravel potential free radical scavenging activity, antioxidant activity, and total phenolic and flavonoid contents of some legumes' hulls extracted by different solvents and evaluate their efficacy to enhance sunflower oil stability.

METHOD

Legume hulls extracted by different solvents were evaluated for their antioxidant activity coefficient (AAC), free radical scavenging activity [by 2,2-diphenyl-1- picrylhydrazyl (DPPH)], and phenolic and flavonoids contents. The protection factor and induction periods (rancimat test) of the highest activity extracts were evaluated.

RESULTS

Sunflower seed hull ethyl acetate extract, lupine seed hull ethanol extract, and mung bean hull petroleum ether extract exhibited stronger DPPH scavenging activity, AAC, and protection factor values than other solvents. Ethyl acetate extracts of sunflower seed hulls showed an antioxidant and scavenging activity close (P>0.05) to that detected for α-tocopherol.

CONCLUSIONS

Legume hulls may possess strong free radical scavenging and antioxidant activity. The analogous effect between sunflower hull extract and α-tocopherol make it a potential, cheaper substitute of α-tocopherol in food systems.

HIGHLIGHTS

The analogous effect between sunflower hull extract and α-tocopherol give it the potency to allow substitution at a concentration of 0.5% of sunflower hull ethyl acetate or 1% of lupine hull ethanol extract instead of 0.5% α-tocopherol to enhance induction periods and protection factors of sunflower oil.

The Effect of Electrospun Polycaprolactone Nonwovens Containing Chitosan and Propolis Extracts on Fresh Pork Packaged in Linear Low-Density Polyethylene Films

Fresh meat products are highly perishable and require optimal packaging conditions to maintain and potentially extend shelf-life. Recently, researchers have developed functional, active packaging systems that are capable of interacting with food products, package headspace, and/or the environment to enhance product shelf-life. Among these systems, antimicrobial/antioxidant active packaging has gained considerable interest for delaying/preventing microbial growth and deteriorative oxidation reactions. This study evaluated the effectiveness of active linear low-density polyethylene (LLDPE) films coated with a polycaprolactone/chitosan nonwoven (Film 1) or LLDPE films coated with a polycaprolactone/chitosan nonwoven fortified with Colombian propolis extract (Film 2). The active LLDPE films were evaluated for the preservation of fresh pork loin (longissimus dorsi) chops during refrigerated storage at 4 °C for up to 20 d. The meat samples were analyzed for pH, instrumental color, purge loss, thiobarbituric acid reactive substances (TBARS), and microbial stability (aerobic mesophilic and psychrophilic bacteria). The incorporation of the propolis-containing nonwoven layer provided antioxidant and antimicrobial properties to LLDPE film, as evidenced by improved color stability, no differences in lipid oxidation, and a delay of 4 d for the onset of bacteria growth of pork chops during the refrigerated storage period.

Fabrication of super-high transparent cellulose films with multifunctional performances via postmodification strategy

A transparent versatile cellulose platform film was prepared from Eucalyptus pulp in this work. Based on such cellulose platform, multifunctional cellulose films with ultraviolet-shielding, photochromism, and strong mechanical strength were fabricated via nucleophilic postmodification strategy by introducing a versatile spiropyran moiety into cellulose molecules. The fabricated cellulose films exhibited super-high transmittance up to 96% and performed notable ultraviolet-shielding capacity at 200-400 nm. Moreover, the photochromic performance of cellulose films with color changes could be clearly observed by the naked eyes, and the fluorescent blue could be excited. Besides, the tensile stress of multi-functional cellulose film was about 80 MPa, which was almost 8 times stronger than that of the commercial polyethylene film at the same thickness. It is noteworthy that these superior performances promote such a cellulose platform to be a versatile precursor for fabricating various multi-functional cellulose used in the fields of out-door coating, transparent packaging, optical screen,etc.

Evaluation of bioactive release kinetics from crosslinked chitosan films with Aloe vera

Thermocompression was employed to prepare citric acid-crosslinked chitosan films with Aloe vera (AV) as bioactive compound. Films were easy to handle and mechanical properties did not change with the addition of AV up to 10 wt%, although both TS and EAB decreased for the films with 15 wt% AV, indicating that high AV contents would hinder intermolecular interactions among the formulation components. Maillard reaction occurred between chitosan and citric acid at the processing temperature used (115 °C), while physical interactions took place with AV, as shown by FTIR analysis. All films were insoluble but displayed hydration and limited swelling due to both physical and chemical interactions promoted by AV and citric acid, respectively. A slow AV release, governed by a Fickian diffusion controlled mechanism, and an increase of surface hydrophilicity, which favors cell adhesion, were observed.

LC-ESI-QTOF-MS/MS Characterisation of Phenolics in Herbal Tea Infusion and Their Antioxidant Potential

Ginger (Zingiber officinale R.), lemon (Citrus limon L.) and mint (Mentha sp.) are commonly consumed medicinal plants that have been of interest due to their health benefits and purported antioxidant capacities. This study was conducted on the premise that no previous study has been performed to elucidate the antioxidant and phenolic profile of the ginger, lemon and mint herbal tea infusion (GLMT). The aim of the study was to investigate and characterise the phenolic contents of ginger, lemon, mint and GLMT, as well as determine their antioxidant potential. Mint recorded the highest total phenolic content, TPC (14.35 ± 0.19 mg gallic acid equivalent/g) and 2,2′-azino-bis(3-e-thylbenzothiazoline-6-sulfonic acid), ABTS (24.25 ± 2.18 mg ascorbic acid equivalent/g) antioxidant activity. GLMT recorded the highest antioxidant activity in the reducing power assay, RPA (1.01 ± 0.04 mg ascorbic acid equivalent/g) and hydroxyl radical scavenging assay, •OH-RSA (0.77 ± 0.08 mg ascorbic acid equivalent/g). Correlation analysis showed that phenolic content positively correlated with the antioxidant activity. Venn diagram analysis revealed that mint contained a high proportion of exclusive phenolic compounds. Liquid chromatography coupled with electrospray ionisation and quadrupole time of flight tandem mass spectrometry (LC-ESI-QTOF-MS/MS) characterised a total of 73 phenolic compounds, out of which 11, 31 and 49 were found in ginger, lemon and mint respectively. These characterised phenolic compounds include phenolic acids (24), flavonoids (35), other phenolic compounds (9), lignans (4) and stilbene (1). High-performance liquid chromatography photometric diode array (HPLC-PDA) quantification showed that GLMT does contain a relatively high concentration of phenolic compounds. This study presented the phenolic profile and antioxidant potential of GLMT and its ingredients, which may increase the confidence in developing GLMT into functional food products or nutraceuticals.

Synergistic Antimicrobial Activities of Thai Household Essential Oils in Chitosan Film

Foodborne pathogens mostly contaminate ready-to-eat (RTE) meat products by post-process contamination and cause foodborne disease outbreaks. Preventing post-process contamination and controlling microbial growth during storage by packing the RTE meats with active antimicrobial film from chitosan combined with the synergism of Thai household essential oils was investigated. Here, we analyzed antimicrobial activity and mechanical properties of chitosan films incorporated with essential oil of fingerroot (EOF) and holy basil (EOH) based on their fractional inhibitory concentration and isobolograms. We showed that antimicrobial activities of chitosan film and chitosan films formulated with EOF:EOH displayed a dramatical reduction of Listeria monocytogenes Scott A concentration by 7 Log in 12 h. Chitosan film incorporated with EOF:EOH at ratio 0.04:0.04% v/v/w strongly retarded growth of total viable count of L. monocytogenes on vacuum-packed bologna slices during seven days of storage at 4 and 10 °C. Combined EOF and EOH added to chitosan films did not alter thickness, elongation (%) and colors (L*, a* and b*) of the chitosan film, but it increased water vapor transmission rate and decreased film tensile strength. Results suggested that chitosan film had strong antibacterial properties. Its effectiveness in inhibiting foodborne pathogenic bacteria in ready-to-eat meat products was enhanced by adding a combination of EOF:EOH.

Development of an eco-friendly biodegradable plastic from jack fruit peel cellulose with different plasticizers and Boswellia serrata as filler

Pure nanocellulose was extracted from agricultural waste material namely jackfruit (Artocarpus heterophyllus) peel through acid hydrolysis. The extraction method utilizes soapnut solution as an eco-friendly bleaching agent in order to avoid environment polluting chlorinated chemicals. Various thin films were prepared by solvent casting nanocellulose and different plasticizers namely glycerol, polyethylene glycol, polyvinyl alcohol, triethyl citrate along with novel filler, Boswellia serrata commonly known as frankincense. Thin films were characterized by FT-IR, XRD and the surface modifications were investigated using FESEM. The physical, mechanical, thermal properties and biodegradability of the film were also reported. The surface morphology was improved by different plasticizers and a self-assembly was obtained due to more stable hydrogen bonding between the nanocellulose, plasticizers and filler during the film formation. Thermal investigations of plasticizers/Boswellia serrata incorporated thin films revealed an increase in glass transition temperature of nanocellulose. Results indicate that these films are biodegradable and compostable in nature and could be used as substitute for petroleum derived plastics.

Nopal cladode as a novel reinforcing and antioxidant agent for starch-based films: A comparison with lignin and propolis extract

The potential use of nopal cladode flour (NC) as reinforcing/bioactive agent in cassava starch-based films was evaluated and compared with the use of propolis extract or lignin, which are commonly used for these purposes. Cassava starch-based films containing untreated NC (S-NC), NC treated at pH 12 (S-NC12), aqueous propolis extract at two different concentrations (SP1 or SP2), or lignin (S-L) were produced by the casting technique; glycerol was used as plasticizer. NC12 and NC affected the mechanical properties of the cassava starch-based film similarly as compared to propolis extract and lignin. Moreover, NC and NC12 had different performance as reinforcing and antioxidant agent in cassava starch-based film. Thus, S-NC12 film was more elongable (28.5 ± 6.5%), more hydrophobic (contact angle: 70.8° ± 0.1), less permeable to water vapor (0.8 ± 0.0 × 10^-10 g·m^-1·s^-1·Pa^-1) and had better antioxidant activity by ABTS^•+ (44.70 ± 0.3 μM Trolox·g^-1 of film) than the S-NC film. SEM and TGA analysis of films showed that NC12 was better incorporated into the cassava starch matrix than NC, lignin and propolis extract. Overall, nopal cladode flour has potential use in the production of active biodegradable packaging for the food preservation with high oxidation rate.

Development of active and smart packaging films based on starch, polyvinyl alcohol and betacyanins from different plant sources

In this study, active and smart packaging films were prepared by individually adding betacyanins-rich plant extracts (red pitaya flesh extract (RPFE), prickly pear fruit extract (PPFE), red beetroot extract (RBRE), globe amaranth flower extract (GAFE) and red amaranth leaf extract (RALE)) into starch/polyvinyl alcohol. The structural, physical and functional properties of the films containing betacyanins from different plant sources were compared for the first time. Results showed betacyanins from RPFE, PPFE and RBRE were betanin-type betacyanins. Betacyanins from GAFE and RALE were gomphrenin-type and amaranthin-type betacyanins, respectively. The films containing RPFE and PPFE presented more uniform cross-sections and had the highest water vapor barrier (9.37 and 9.26 × 10^-11 g m^-1 s^-1 Pa^-1) and mechanical strength (8.26 and 7.87 MPa). However, the film containing GAFE presented the lowest light transmittance but the highest 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (EC₅₀ = 0.47 mg/mL). All the films containing betacyanins are sensitive to pH 8-12 buffer solutions and volatile ammonia. Notably, the film containing RPFE exhibited distinct color changes (from purple-red to pink) when shrimp spoiled. Our results suggest the structural, physical and functional properties of betacyanins-rich films are closely related to the source and type of betacyanins.

Superhydrophobic and Antioxidative Film Based on Edible Materials for Food Packaging

Significant wastage of the food deterioration in the food preserving process and residual liquid in a container has become a major concern for scientists and the whole society. In this study, an edible multifunctional film integrated superhydrophobicity and antioxidant ability is constructed by chitosan, tea polyphenol, carnauba wax material that is food and drug administration (FDA)-approved for food packaging. The formed edible packaging materials that exhibit great antioxidant property and extremely low water-absorbing quality, was thus proven to display excellent fresh beef preservation effect during storage of 14 days. Importantly, the formed edible multifunctional interface was also demonstrated to perform excellent superhydrophobicity due to the carnauba wax and exhibited large contact angles for various liquid foods, which could effectively reduce the liquid residue. Moreover, the formed edible multifunctional packaging materials showed good thermostability and biocompatibility, which has the potential to be applied as a functional packaging material.

Pomegranate By-Products as Natural Preservative to Prolong the Shelf Life of Breaded Cod Stick

This work evaluated the efficacy of pomegranate byproducts, specifically peel powder, as valid preservatives for food quality. Ready-to-cook cod sticks breaded with pomegranate peel powder were prepared. Shelf-life tests were conducted on breaded cod sticks during refrigerated storage (17 days) at 4 °C, monitoring the pH, microbiological and sensory quality. In addition, the nutritional quality of both the breaded and control samples was assessed. The results highlighted that active samples showed higher phenol and flavonoid content and higher antioxidant activity compared to the control fish, suggesting that pomegranate peel powder was responsible for a significant increase in cod stick nutritional quality. Furthermore, the cod stick active breading led to a delay in microbial growth without affecting the sensory properties; rather, it helped slow down the sensory attribute decline during the refrigerated storage. The data suggest that using pomegranate byproducts in breaded cod stick was effective in prolonging its shelf life, as well as improving its nutritional quality. Therefore, pomegranate peel powder can be considered as a potential resource as natural food preservative.

Functionalities of chitosan conjugated with lauric acid and l-carnitine and application of the modified chitosan in an oil-in-water emulsion

The aim of this research was to conjugate chitosan (CT) with lauric acid (LA) and l-carnitine (CNT) to yield a product that is water-soluble at neutral pH and has surface, antimicrobial, and antioxidant activities. The resulting CT-LA-CNT is water-soluble at neutral pH, in contrast with CT and CT-LA, which require the aid of acid to become soluble. Concerning antimicrobial activity, for S. aureus, the minimum bactericidal concentration of CT was lower than those of CT-LA or CT-LA-CNT, while the three compounds exhibited similar bactericidal activity against E. coli. CT-LA-CNT was also used to study the oxidative stability of soybean oil in an oil-in-water (O/W) emulsion; sodium dodecyl sulfate (SDS) and Tween 80 and Span 80 (TS), an emulsifier mixture, were used as controls for comparison. The results showed that CT-LA-CNT was better than SDS and TS at protecting the lipid from oxidation.

Chemical and physical Chitosan modification for designing enzymatic industrial biocatalysts: How to choose the best strategy?

Chitosan is one of the most abundant natural polymer worldwide, and due to its inherent characteristics, its use in industrial processes has been extensively explored. Because it is biodegradable, biocompatible, non-toxic, hydrophilic, cheap, and has good physical-chemical stability, it is seen as an excellent alternative for the replacement of synthetic materials in the search for more sustainable production methodologies. Thus being, a possible biotechnological application of Chitosan is as a direct support for enzyme immobilization. However, its applicability is quite specific, and to overcome this issue, alternative pretreatments are required, such as chemical and physical modifications to its structure, enabling its use in a wider array of applications. This review aims to present the topic in detail, by exploring and discussing methods of employment of Chitosan in enzymatic immobilization processes with various enzymes, presenting its advantages and disadvantages, as well as listing possible chemical modifications and combinations with other compounds for formulating an ideal support for this purpose. First, we will present Chitosan emphasizing its characteristics that allow its use as enzyme support. Furthermore, we will discuss possible physicochemical modifications that can be made to Chitosan, mentioning the improvements obtained in each process. These discussions will enable a comprehensive comparison between, and an informed choice of, the best technologies concerning enzyme immobilization and the application conditions of the biocatalyst.

Extraction of Tropical Fruit Peels and Development of HPMC Film Containing the Extracts as an Active Antibacterial Packaging Material

In recent years, instead of the use of chemical substances, alternative substances, especially plant extracts, have been characterized for an active packaging of antibacterial elements. In this study, the peels of mangosteen (Garcinia mangostana), rambutan (Nephelium lappaceum), and mango (Mangifera indica) were extracted to obtain bioactive compound by microwave-assisted extraction (MAE) and maceration with water, ethanol 95% and water–ethanol (40:60%). All extracts contained phenolics and flavonoids. However, mangosteen peel extracted by MAE and maceration with water/ethanol (MT-MAE-W/E and MT-Ma-W/E, respectively) contained higher phenolic and flavonoid contents, and exhibited greater antibacterial activity against Staphylococcus aureus and Escherichia coli. Thus, both extracts were analyzed by liquid chromatograph-mass spectrometer (LC-MS) analysis, α-mangostin conferring antibacterial property was found in both extracts. The MT-MAE-W/E and MT-Ma-W/E films exhibited 30.22 ± 2.14 and 30.60 ± 2.83 mm of growth inhibition zones against S. aureus and 26.50 ± 1.60 and 26.93 ± 3.92 mm of growth inhibition zones against E. coli. These clear zones were wider than its crude extract approximately 3 times, possibly because the film formulation enhanced antibacterial activity with sustained release of active compound. Thus, the mangosteen extracts have potential to be used as an antibacterial compound in active packaging.

Blends of Poly(3-Hydroxybutyrate-co-3-Hydroxyvalerate) with Fruit Pulp Biowaste Derived Poly(3-Hydroxybutyrate-co-3-Hydroxyvalerate-co-3-Hydroxyhexanoate) for Organic Recycling Food Packaging

In the present study, a new poly(3-hydroxybutyrate-co-3-hydroxyvalerate-co-3-hydroxyhexanoate) [P(3HB-co-3HV-co-3HHx)] terpolyester with approximately 68 mol% of 3-hydroxybutyrate (3HB), 17 mol% of 3-hydroxyvalerate (3HV), and 15 mol% of 3-hydroxyhexanoate (3HHx) was obtained via the mixed microbial culture (MMC) technology using fruit pulps as feedstock, a processing by-product of the juice industry. After extraction and purification performed in a single step, the P(3HB-co-3HV-co-3HHx) powder was melt-mixed, for the first time, in contents of 10, 25, and 50 wt% with commercial poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). Thereafter, the resultant doughs were thermo-compressed to obtain highly miscible films with good optical properties, which can be of interest in rigid and semirigid organic recyclable food packaging applications. The results showed that the developed blends exhibited a progressively lower melting enthalpy with increasing the incorporation of P(3HB-co-3HV-co-3HHx), but retained the PHB crystalline morphology, albeit with an inferred lower crystalline density. Moreover, all the melt-mixed blends were thermally stable up to nearly 240 °C. As the content of terpolymer increased in the blends, the mechanical response of their films showed a brittle-to-ductile transition. On the other hand, the permeabilities to water vapor, oxygen, and, more notably, limonene were seen to increase. On the overall, this study demonstrates the value of using industrial biowaste derived P(3HB-co-3HV-co-3HHx) terpolyesters as potentially cost-effective and sustainable plasticizing additives to balance the physical properties of organic recyclable polyhydroxyalkanoate (PHA)-based food packaging materials.

Effect of Gaseous Ozone Process on Cantaloupe Melon Peel: Assessment of Quality and Antilisterial Indicators

Fruit waste parts, particularly peel, are abundant sources of bioactive compounds. To be included in the formulation of value-added foods, peel needs to be transformed and subjected to a preservation process. Therefore, this study seeks to assess the effect of ozone on the quality and antilisterial indicators of cantaloupe melon peel paste, aiming at obtaining a product with the potential to be used as a food additive. Ozone was bubbled during 30 and 60 min, and some physicochemical characteristics (soluble solids content, pH and colour), bioactive compounds (total phenolics, chlorophylls and vitamin C) and antioxidant activity were analysed. Peel was also inoculated with Listeria innocua, used as a treatment efficiency indicator. The results indicated that, although ozone negatively affected antioxidant activity, it positively influenced all bioactive compounds analysed. An L. innocua reduction of 1.2 log cycle was achieved after ozone exposure. Ozone should be exploited as a promising technology to assure the quality/safety of cantaloupe melon peel. Indeed, if melon peel is conveniently converted into a suitable form that can be used as a food ingredient, this will promote the valorisation of waste materials with the consequent reduction of industrial by-products and new perspectives for market opportunities.

Chitosan Films Obtained from Brachystola magna (Girard) and Its Evaluation on Quality Attributes in Sausages during Storage

High molecular weight chitosan (≈322 kDa) was obtained from chitin isolated from Brachystola magna (Girard) to produced biodegradable films. Their physicochemical, mechanical and water vapor permeability (WVP) properties were compared against commercial chitosan films with different molecular weights. Brachystola magna chitosan films (CFBM) exhibited similar physicochemical and mechanical characteristics to those of commercial chitosans. The CFBM films presented lower WVP values (10.01 × 10⁻¹¹ g/m s Pa) than commercial chitosans films (from 16.06 × 10⁻¹¹ to 64.30 × 10⁻¹¹ g/m s Pa). Frankfurt-type sausages were covered with chitosan films and stored in refrigerated conditions (4 °C). Their quality attributes (color, weight loss, pH, moisture, texture and lipid oxidation) were evaluated at 0, 5, 10, 15 and 20 days. Sausages covered with CFMB films presented the lowest weight loss (from 1.24% to 2.38%). A higher increase in hardness (from 22.32 N to 30.63 N) was observed in sausages covered with CFMB films. Compared with other films and the control (uncovered sausages), CFMB films delay pH reduction. Moreover, this film presents the lower lipid oxidation level (0.10 malonaldehyde mg/sample kg). Thus, chitosan of B. magna could be a good alternative as packaging material for meat products with high-fat content.

Bio-Based Sensors for Smart Food Packaging-Current Applications and Future Trends

Intelligent food packaging is emerging as a novel technology, capable of monitoring the quality and safety of food during its shelf-life time. This technology makes use of indicators and sensors that are applied in the packaging and that detect changes in physiological variations of the foodstuffs (due to microbial and chemical degradation). These indicators usually provide information, e.g., on the degree of freshness of the product packed, through a color change, which is easily identified, either by the food distributor and the consumer. However, most of the indicators that are currently used are non-renewable and non-biodegradable synthetic materials. Because there is an imperative need to improve food packaging sustainability, choice of sensors should also reflect this requirement. Therefore, this work aims to revise the latest information on bio-based sensors, based on compounds obtained from natural extracts, that can, in association with biopolymers, act as intelligent or smart food packaging. Its application into several perishable foods is summarized. It is clear that bioactive extracts, e.g., anthocyanins, obtained from a variety of sources, including by-products of the food industry, present a substantial potential to act as bio-sensors. Yet, there are still some limitations that need to be surpassed before this technology reaches a mature commercial stage.

Characterization of polyvinyl alcohol/starch composite films incorporated with p-coumaric acid modified chitosan and chitosan nanoparticles: A comparative study

In this paper, polyvinyl alcohol/starch composite films with p-coumaric acid modified chitosan (P-CS) and chitosan nanoparticles (P-CSNPs) at different concentrations were successfully prepared. The films were compared for their mechanical, thermal, physical, antioxidant, antibacterial, cytotoxicity and optical barrier properties. The results suggested that P-CS could significantly increase the tensile strength (TS) of the film from 15.67 MPa to a maximum of 24.32 MPa. The compact structure of P-CSNPs film prevented water diffusion, reducing the water amount within. Both films showed a reduction in water solubility, the extent of swelling, and water vapor transmittance. Specifically, P-CSNPs films showed better thermal stability while P-CS films revealed higher antioxidant activity. Besides, the P-CS films exhibited excellent transparency and good ultraviolet-barrier at 200-280 nm. P-CSNPs films demonstrated higher antibacterial activity on both Gram-negative and Gram-positive bacteria. Additionally, P-CS films were less cytotoxic compared to P-CSNPs films.

High-Amylose Corn Starch/Konjac Glucomannan Composite Film: Reinforced by Incorporating β-Cyclodextrin

Glycerol-plasticized high-amylose corn starch/konjac glucomannan (HCS/KGM) composite films incorporated with various concentrations of β-cyclodextrin (β-CD) were prepared and investigated for structural, mechanical, and physical properties. The results of X-ray diffraction, attenuated total reflectance Fourier transform infrared spectroscopy, thermogravimetric analyses, and scanning electron microscopy indicated that β-CD excluded from the polymer chains and aggregated to form crystals during film formation, which drove HCS to interact with KGM more compactly. The thickness and transparency of the films increased after β-CD was incorporated. More associations of HCS/KGM enhanced the mechanical properties and reduced the moisture content of the films. The water vapor permeability of the HCS/KGM composite film was also improved significantly with the incorporation of β-CD. The enhanced association between biopolymers in the presence of β-CD will advance the development of a degradable active composite packaging film.

Eco-friendly natural extract loaded antioxidative chitosan/polyvinyl alcohol based active films for food packaging

Nowadays, biodegradable antimicrobial packaging materials draw substantial attention and are considered one of the preferred emerging technologies to be used in the food industry. In this study, we have reported developing a two-component, chitosan (CS) and polyvinyl alcohol (PVA) based films loaded with natural extract of Ocimum tenuiflorum via solvent casting technique. Experimental results showed that all the components were well dispersed, resulting in complete homogenous films. FTIR-ATR spectral analysis indicated strong interaction between the film matrix components, which also gets reflected by the films' physical properties. Transparent biodegradable films have resulted from the mixture and incorporation of the natural agent/extracts influenced light barrier, water resistance, moisture content (9.89-9.01%), and DPPH radical scavenging properties (antioxidant value ~41.1%) of the CS/PVA films. Therefore, this natural extract containing transparent CS/PVA-based films promises to be used in the food industry as packaging material to enhance food safety.

Trends in Chitosan as a Primary Biopolymer for Functional Films and Coatings Manufacture for Food and Natural Products

Some of the current challenges faced by the food industry deal with the natural ripening process and the short shelf-life of fresh and minimally processed products. The loss of vitamins and minerals, lipid oxidation, enzymatic browning, and growth of microorganisms have been the main issues for many years within the innovation and improvement of food packaging, which seeks to preserve and protect the product until its consumption. Most of the conventional packaging are petroleum-derived plastics, which after product consumption becomes a major concern due to environmental damage provoked by their difficult degradation. In this sense, many researchers have shown interest in edible films and coatings, which represent an environmentally friendly alternative for food packaging. To date, chitosan (CS) is among the most common materials in the formulation of these biodegradable packaging together with polysaccharides, proteins, and lipids. The good film-forming and biological properties (i.e., antimicrobial, antifungal, and antiviral) of CS have fostered its usage in food packaging. Therefore, the goal of this paper is to collect and discuss the latest development works (over the last five years) aimed at using CS in the manufacture of edible films and coatings for food preservation. Particular attention has been devoted to relevant findings in the field, together with the novel preparation protocols of such biodegradable packaging. Finally, recent trends in new concepts of composite films and coatings are also addressed.

Antioxidant and Antibacterial Activity of Caprylic Acid Vanillyl Ester Produced by Lipase-Mediated Transesterification

Vanillyl alcohol (VA), which is abundant in Vanilla bean, has strong antioxidant activity. However, the use of VA in the food and cosmetics industries is limited, due to its low solubility in emulsion or organic solvents. Meanwhile, medium chain fatty acids and medium chain monoglycerides have antibacterial activity. We synthesized butyric acid vanillyl ester (BAVE) or caprylic acid vanillyl ester (CAVE) from VA with tributyrin or tricaprylin through transesterification reaction using immobilized lipases. BAVE and CAVE scavenged 2,2-diphenyl-1-picrylhydrazyl radicals in organic solvents. In addition, BAVE and CAVE decreased the production rate of conjugated diene and triene in the menhaden oil-in-water emulsion system. While BAVE showed no antibacterial activity, CAVE showed antibacterial activity against food spoilage bacteria, including Bacillus coagulans. In this study, the antibacterial activity of vanillyl ester with medium chain fatty acid was first revealed. Zeta potential measurements confirmed that BAVE and CAVE were inserted into B. coagulans membrane. In addition, the propidium iodide uptake assay and fluorescent microscopy showed that CAVE increased B. coagulans membrane permeability. Therefore, CAVE is expected to play an important role in the food and cosmetics industries as a bi-functional material with both antioxidant and antibacterial activities.

Effect of Chitosan Coating Incorporated with Artemisia fragrans Essential Oil on Fresh Chicken Meat during Refrigerated Storage

The present study was conducted to assess the impact of chitosan coating (1%) containing Artemisia fragrans essential oil (500, 1000, and 1500 ppm) as antioxidant and antimicrobial agent on the quality properties and shelf life of chicken fillets during refrigerated storage. After packaging meat samples, physicochemical, microbiological, and organoleptic attributes were evaluated at 0, 3, 6, 9, and 12 days at 4 °C. The results revealed that applied chitosan (CH) coating in combination with Artemisia fragrans essential oils (AFEOs) had no significant (p < 0.05) effects on proximate composition among treatments. The results showed that the incorporation of AFEOs into CH coating significantly reduced (p < 0.05) pH, thiobarbituric acid reactive substances (TBARS), and total volatile base nitrogen (TVB-N), especially for 1% CH coating + 1500 ppm AFEOs, with values at the end of storage of 5.58, 1.61, and 2.53, respectively. The coated samples also displayed higher phenolic compounds than those obtained by uncoated samples. Coated chicken meat had, significantly (p < 0.05), the highest inhibitory effects against microbial growth. The counts of TVC (total viable counts), coliforms, molds, and yeasts were significantly lower (p < 0.05) in 1% CH coating + 1500 ppm AFEOs fillets (5.32, 3.87, and 4.27 Log CFU/g, respectively) at day 12. Organoleptic attributes of coated samples also showed the highest overall acceptability scores than uncoated ones. Therefore, the incorporation of AFEOs into CH coating could be effectively used for improving stability and shelf life of chicken fillets during refrigerated storage.

Progresses in Food Packaging, Food Quality, and Safety-Controlled-Release Antioxidant and/or Antimicrobial Packaging

Food packaging is designed to protect foods, to provide required information about the food, and to make food handling convenient for distribution to consumers. Packaging has a crucial role in the process of food quality, safety, and shelf-life extension. Possible interactions between food and packaging are important in what is concerning food quality and safety. This review tries to offer a picture of the most important types of active packaging emphasizing the controlled/target release antimicrobial and/or antioxidant packaging including system design, different methods of polymer matrix modification, and processing. The testing methods for the appreciation of the performance of active food packaging, as well as mechanisms and kinetics implied in active compounds release, are summarized. During the last years, many fast advancements in packaging technology appeared, including intelligent or smart packaging (IOSP), (i.e., time-temperature indicators (TTIs), gas indicators, radiofrequency identification (RFID), and others). Legislation is also discussed.

Aging Studies on Food Packaging Films Containing β-Cyclodextrin-Grafted TiO2 Nanoparticles

Polymeric materials, such as polyvinyl alcohol (PVA) and ethylene–PVA copolymers (EVOH) are widely used in the food sector as packaging materials because of their excellent properties. TiO₂ nanoparticles (NPs) show photocatalytic activity; when added to the aforementioned polymers, on the one hand, they are expected to provide bactericidal capacity, whereas on the other hand, they could favor nanocomposite degradation. These types of nanoparticles can be derivatized with cyclodextrin macromolecules (CDs), which can act as food preservative carriers, increasing the packaging food protective properties. In this work, films containing β-Cyclodextrin (βCD)-grafted TiO₂ nanoparticles and PVA or EVOH were prepared. Regarding the photocatalytic activity of the nanoparticles and the possible environmental protection, accelerated aging tests for PVA, EVOH, and their composites with cyclodextrin-grafted TiO₂ nanoparticle (NP) films were performed by two methods, namely, stability chamber experiments at different conditions of temperature and relative humidity and UV light irradiation at different intensities. After analyzing the systems color changes (CIELAB) and Fourier transform infrared spectroscopy (FTIR) spectra, it was observed that the film degradation became more evident when increasing the temperature (25–80 °C) and relative humidity percentage (28–80%). There was no significant influence of the presence of CDs during the degradation process. When irradiating the films with UV light, the largest color variation was observed in the nanocomposite films, as expected. Moreover, the color change was more relevant with increasing NP percentages (1–5%) due to the high photocatalytic activity of TiO₂. In addition, films were characterized by FTIR spectroscopy and variation in the signal intensities was observed, suggesting the increase of the material degradation in the presence of TiO₂ NPs.

Designing active mats based on cellulose acetate/polycaprolactone core/shell structures with different release kinetics

Core/shell electrospun mats based on cellulose acetate (CA) and polycaprolactone (PCL) were developed as novel active materials for releasing quercetin (Quer) and curcumin (Cur). The effect of polymeric uniaxial and coaxial electrospun systems and the chemical structures of Quer and Cur on the structural, thermal, and mass transfer properties of the developed mats were investigated. Release modelling indicated that the diffusion of the active agents from the uniaxial PCL fibers was highly dependent on the type of food simulant. Higher diffusion coefficients were obtained for both active agents in acid food simulant due to the higher swelling of the electrospun mats. In addition, CA/PCL coaxial structures slowed down the diffusion of both active agents into both food simulants. CA increased the retention of the active compounds in the polymer structure, resulting in partition coefficients values higher than the values obtained for uniaxial active PCL mats.

Hydroxy citric acid cross-linked chitosan/guar gum/poly(vinyl alcohol) active films for food packaging applications

The present work aims to prepare Chitosan (CS)/Guar gum (GG)/Poly(vinyl alcohol) (PVA) cross-linked with Hydroxy citric acid (HCA) (CGPH active film) by solvent casting technique. The influence of HCA on different CS/PVA ratio (1:3, 1:1, 3:1) in presence of the fixed amount of GG (0.2%) was investigated. The analysis of the results showed that the addition of HCA to the different ratio of CS/PVA increased the degradation temperature and improved the mechanical properties of CGPH active films. FTIR spectra and XRD analysis revealed strong interactions among the components of CGPH active films. The analysis of SEM images and water contact angle suggested a compact, dense film surface with hydrophobic nature. Further, all the active films have shown a decrease in water vapour permeability (WVP) and acted as a barrier to UV-light. CGPH active films effectively inhibited the growth of S. aureus and E. coli bacteria. With all these features the CGPH active films can find application in food packaging.

Optimization of the Vacuum Microwave Assisted Extraction of the Natural Polyphenols and Flavonoids from the Raw Solid Waste of the Pomegranate Juice Producing Industry at Industrial Scale

Pomegranate pomace (PP) is the solid waste produced in bulk by the pomegranate juice industry which is rich in polyphenols and flavonoids that can replace the hazardous chemical antioxidants/antimicrobials currently used in the agro-food and cosmetics sectors. In the present work, the vacuum microwave assisted extraction (VMAE) of natural antioxidants from raw pomegranate pomace was investigated and successfully optimized at an industrial scale. For the optimization of PP VMAE a novel, highly accurate response surface methodology (RSM) based on a comprehensive multi-point historical design was employed. The optimization showed that the maximum recovery of PP total polyphenols as well as total PP flavonoids were obtained at microwave power = 4961.07 W, water to pomace ratio = 29.9, extraction time = 119.53 min and microwave power = 4147.76 W, water to pomace ratio = 19.32, extraction time = 63.32 min respectively. Moreover, the optimal VMAE conditions on economic grounds were determined to be: microwave power = 2048.62 W, water to pomace ratio = 23.11, extraction time = 15.04 min and microwave power = 4008.62 W, water to pomace ratio = 18.08, extraction time = 15.29 min for PP total polyphenols and PP total flavonoids respectively. The main conclusion of this study is that the VMAE extraction can be successfully used at industrial scale to produce, in economic manner, high added value natural extracts from PP pomace.

Colorimetric indicator based on purple tomato anthocyanins and chitosan for application in intelligent packaging

Intelligent colorimetric indicator films were prepared to monitor freshness/spoilage of milk and fish by incorporating purple tomato anthocyanin (PTA) into chitosan (CS) matrix via solution casting method with PTA concentration (w/w, based on CS) of 10%, 30%, and 50%, respectively. The pH-response, UV absorption, Swelling Index, and the mechanical properties of CS/PTA films were determined. It was found that the color of the original CS/PTA films became darker with an improvement of PTA content and expressed well pH-sensitivity. With increasing of pH, the color of the CS/PTA films exposed to pH = 3-11 solutions became darker and the change in color of the CS/10% PTA film was the most discernable. The tensile strength and Young's modulus of the CS/PTA film was much lower than that of CS film, however, the elongation at breaking and Swelling Index were both improved by adding PTA. The intelligent films with 10% PTA changed their color during progressive spoilage of milk or fish, revealing their potential application for monitoring food freshness/spoilage.