Physicochemical responses and microbiological changes of bream (Megalobrama ambycephala) to pectin based coatings enriched with clove essential oil during refrigeration

Chitosan/gelatin coating loaded with ginger essential oil/β-cyclodextrin inclusion complex on quality and shelf life of blueberries

Blueberries are highly susceptible to fungal pathogens and oxidative deterioration due to their thin epidermal layer, which can be mitigated by applying a natural polymer-based antimicrobial coating to their surface. This study aimed to develop a chitosan/gelatin-based antimicrobial coating utilizing ginger essential oil (GEO) to extend the postharvest quality of blueberries. To ensure GEO's stability within the coating, it was initially encapsulated with β-cyclodextrin (β-CD) using the inclusion complexation technique. The GEO/β-CD inclusion complex (IC) formed rhomboidal shapes with high encapsulation efficiency and small particle sizes. When the optimized GEO/β-CD IC was incorporated into the chitosan/gelatin polymer solution, it significantly increased surface hydrophobicity and free radical scavenging activity, and suppressed the growth of three selected fungi, namely Botrytis cinerea, Penicillium italicum and Alternaria alternaria. The results of postharvest storage quality revealed that blueberry samples coated with CH/Gel-GEO/β-CD IC-5 effectively maintained the quality of blueberries by decreasing weight loss and decay incidence, and regulating anthocyanin and other oxidation-related enzyme activities compared to the control group during 16 days at 25 °C and 40 days at 4 °C storages. In conclusion, it can be stated that CH/Gel-GEO/β-CD composite coating can be a promising technology to address the drawbacks of blueberry preservation.

Efficient pectin recovery from sugar beet pulp as effective bio-based coating for Pacific white shrimp preservation

This study demonstrates the valorization of sugar beet pulp (SBP)-derived pectin to produce bio-based coatings for shrimp preservation. Pectin extraction was assessed at varying temperatures and extraction times to achieve tailored properties (high methoxyl-pectins, degree of esterification-DE >79.0 %) leading to 11.5 % extraction yield, 78.1 % galactouronic acid content and 80 % DE at optimal conditions (pH 1.5, 80 °C, 2 h). Pectin-based coatings supplemented with ascorbic acid (AA) (0.5-2.0 %) led to organoleptically acceptable shrimps with significantly lower total color differences during 28-days of storage, compared to uncoated and pectin-coated counterparts. AA-based coatings delayed shrimp melanosis, expressed as reduced polyphenoloxidase activity (48-86 %). Rich-in-holocellulose solids derived after pectin extraction were used for bacterial cellulose (BC) production, pinpointing the SBP potential as a multi-purpose feedstock. Fed-batch fermentation enhanced BC concentration (by 110 %) and productivity (1.6-fold higher) compared to batch-cultures. Pectin produced within a SBP-based biorefinery could be applied as bio-based coating with food packaging potential.

Clove Essential Oil: Chemical Profile, Biological Activities, Encapsulation Strategies, and Food Applications

Plants have proven to be important sources for discovering new compounds that are useful in the treatment of various diseases due to their phytoconstituents. Clove (Syzygium aromaticum L.), an aromatic plant widely cultivated around the world, has been traditionally used for food preservation and medicinal purposes. In particular, clove essential oil (CEO) has attracted attention for containing various bioactive compounds, such as phenolics (eugenol and eugenol acetate), terpenes (β-caryophyllene and α-humulene), and hydrocarbons. These constituents have found applications in cosmetics, food, and medicine industries due to their bioactivity. Pharmacologically, CEO has been tested against a variety of parasites and pathogenic microorganisms, demonstrating antibacterial and antifungal properties. Additionally, many studies have also demonstrated the analgesic, antioxidant, anticancer, antiseptic, and anti-inflammatory effects of this essential oil. However, CEO could degrade for different reasons, impacting its quality and bioactivity. To address this challenge, encapsulation is viewed as a promising strategy that could prolong the shelf life of CEO, improving its physicochemical stability and application in various areas. This review examines the phytochemical composition and biological activities of CEO and its constituents, as well as extraction methods to obtain it. Moreover, encapsulation strategies for CEO and numerous applications in different food fields are also highlighted.

Shelf-life extension of Pacific white shrimp (Litopenaeus vannamei) using sodium alginate/chitosan incorporated with cell-free supernatant of Streptococcus thermophilus FUA 329 during cold storage

Seafood is highly perishable and has a short shelf-life. This study investigated the effect of chitosan and alginate (CH-SA) coating combined with the cell-free supernatant of Streptococcus thermophilus FUA329 (CFS) as a preservative on the quailty of white shrimp (Litopenaeus vannamei) refrigerated at 4° for 0, 3, 6, 9, 12, 15 days. Freshly shrimps were randomly divided into four groups: the CFS group (400 mL); the CH-SA group (1% chitosan/1% alginate); the CFS-CH-SA group (1% chitosan/1% alginate with 400 mL CFS) are treatment groups, and the control group (400 mL sterile water). The CFS-CH-SA coating effectively suppressed microbial growth total viable count and chemical accumulation (pH, total volatile basic nitrogen, thiobarbituric acid reactive substance) compared with the control. Additionally, the CFS-CH-SA coating improved the texture and sensory characteristics of shrimp during storage. The coated shrimp exhibited significantly reduced water loss (p < 0.05). The combination of CH-SA coating with CFS treatment can extend the shelf life of shrimp. PRACTICAL APPLICATION: Recently, edible films have received more consideration as a promising method to enhance the shelf life of seafood. The presence of Lactic acid bacteria metabolites in edible films reduces spoilage and improves consumer health. Our findings encourage the application of edible coating incorporated with cell-free supernatant of Streptococcus thermophilus FUA 329 to design multifubctional foods and preserve the qualities of shrimp.

Effects of slightly acidic electrolyzed water combined with ԑ-polylysine-chitooligosaccharide Maillard reaction products treatment on the quality of vacuum packaged sea bass (Lateolabrax japonicas)

In this study, a new natural preservative, ε-polylysine (ε-PL) and chitooligosaccharides (COS) Maillard reaction products (LC-MRPs), was prepared by Maillard reaction. The preservation effect of LC-MRPs combined with slightly acidic electrolyzed water (SAEW) pretreatment (SM) on vacuum-packed sea bass during refrigerated storage was evaluated. The results showed that after 16 days, SM treatment could effectively inhibit the microbial growth and prevent water migration in sea bass. In addition, the highest water holding capacity (69.79 %) and the best sensory characteristics, the lowest malonaldehyde (MDA) (58.96 nmol/g), trimethylamine (TMA) (3.35 mg/100 g), total volatile basic nitrogen (TVB-N) (16.93 mg N/100 g), myofibril fragmentation index (MFI) (92.2 %) and TCA-soluble peptides (2.16 μmol tyrosine/g meat) were related to SM group. Combined with sensory analysis, we can conclude that the combined treatment of SAEW and LC-MRPs could prolong the shelf-life of sea bass for another 11 days compared with the DW group. Results disclosed that the composite treatment of SAEW and LC-MRPs is a promising technology to improve the shelf-life of vacuum-packed sea bass during refrigerated storage.

Zinc oxide nanoparticle-reinforced pectin/starch functionalized films: A sustainable solution for biodegradable packaging

Environmental pollution caused by non-biodegradable plastic pollutants adversely affects various ecosystems. This study proposes the development of novel functional and biodegradable films based on corn starch (CST) and pectin (PEC) containing zinc oxide nanoparticles (ZnONPs) from the casting method. The films exhibited processability, transparency, low water vapor permeation, and desirable mechanical properties for food packaging and coating applications. The ZnONPs acted as a plasticizer, enhancing the film elongation at the break, increasing the pec25-1 (PEC 25 wt% and ZnONPs 1 wt%) elongation from 79.85 to 162.32 %. The improved film elasticity supported by ZnONPs reduced the material stiffness. However, the films still demonstrated an average tensile strength (0.69 MPa) 17-fold higher than the tensile strength (0.04 MPa) of the non-biodegradable commercial film based on poly(vinyl chloride). Furthermore, the ZnONPs enhanced the UV-blocking capabilities of the films, leading to wettable materials with water contact angles lower than 90°. The films showed high biodegradation rates under natural disposal conditions. The results indicated that the pec25-1/ZnONPs film is a promising eco-friendly coating in food preservation due to its biodegradability, suitable mechanical properties, low water vapor permeability, and UV-blocking properties.

Biological Properties and Biomedical Applications of Pectin and Pectin-Based Composites: A Review

Pectin has recently drawn much attention in biomedical applications due to its distinctive chemical and biological properties. Polymers like pectin with cell-instructive properties are attractive natural biomaterials for tissue repair and regeneration. In addition, bioactive pectin and pectin-based composites exhibit improved characteristics to deliver active molecules. Pectin and pectin-based composites serve as interactive matrices or scaffolds by stimulating cell adhesion and cell proliferation and enhancing tissue remodeling by forming an extracellular matrix in vivo. Several bioactive properties, such as immunoregulatory, antibacterial, anti-inflammatory, anti-tumor, and antioxidant activities, contribute to the pectin's and pectin-based composite's enhanced applications in tissue engineering and drug delivery systems. Tissue engineering scaffolds containing pectin and pectin-based conjugates or composites demonstrate essential features such as nontoxicity, tunable mechanical properties, biodegradability, and suitable surface properties. The design and fabrication of pectic composites are versatile for tissue engineering and drug delivery applications. This article reviews the promising characteristics of pectin or pectic polysaccharides and pectin-based composites and highlights their potential biomedical applications, focusing on drug delivery and tissue engineering.

Pectin Hydrogels: Gel-Forming Behaviors, Mechanisms, and Food Applications

Pectin hydrogels have garnered significant attention in the food industry due to their remarkable versatility and promising properties. As a naturally occurring polysaccharide, pectin forms three-dimensional (3D) hydrophilic polymer networks, endowing these hydrogels with softness, flexibility, and biocompatibility. Their exceptional attributes surpass those of other biopolymer gels, exhibiting rapid gelation, higher melting points, and efficient carrier capabilities for flavoring and fat barriers. This review provides an overview of the current state of pectin gelling mechanisms and the classification of hydrogels, as well as their crosslinking types, as investigated through diverse research endeavors worldwide. The preparation of pectin hydrogels is categorized into specific gel types, including hydrogels, cryogels, aerogels, xerogels, and oleogels. Each preparation process is thoroughly discussed, shedding light on how it impacts the properties of pectin gels. Furthermore, the review delves into the various crosslinking methods used to form hydrogels, with a focus on physical, chemical, and interpenetrating polymer network (IPN) approaches. Understanding these crosslinking mechanisms is crucial to harnessing the full potential of pectin hydrogels for food-related applications. The review aims to provide valuable insights into the diverse applications of pectin hydrogels in the food industry, motivating further exploration to cater to consumer demands and advance food technology. By exploiting the unique properties of pectin hydrogels, food formulations can be enhanced with encapsulated bioactive substances, improved stability, and controlled release. Additionally, the exploration of different crosslinking methods expands the horizons of potential applications.

Recent progress in pectin extraction and their applications in developing films and coatings for sustainable food packaging: A review

Perishable foods like fruits and vegetables, meat, fish, and dairy products have short shelf-life that causes significant postharvest losses, which poses a major challenge for food supply chains. Biopolymers have been extensively studied as sustainable alternatives to synthetic plastics, and pectin is one such biopolymer that has been used for packaging and preservation of foods. Pectin is obtained from abundantly available low-cost sources such as agricultural or food processing wastes and by products. This review is a complete account of pectin extraction from agro-wastes, development of pectin-based composite films and coatings, their characterizations, and their applications in food packaging and preservation. Compared to conventional chemical extraction, supercritical water, ultrasound, and microwave assisted extractions are a few examples of modern and more efficient pectin extraction processes that generate almost no hazardous effluents, and thus, such extraction techniques are more environment friendly. Pectin-based films and coatings can be functionalized with natural active agents such as essential oils and other phytochemicals to improve their moisture barrier, antimicrobial and antioxidant properties. Application of pectin-based active films and coatings effectively improved shelf-life of fresh cut-fruits, vegetables, meat, fish, poultry, milk, and other food perishable products.

A Review of Regulatory Standards and Advances in Essential Oils as Antimicrobials in Foods

As essential oils (EOs) possess GRAS status, there is a strong interest in their application to food preservation. Trends in the food industry suggest consumers are drawn to environmentally friendly alternatives and less synthetic chemical preservatives. Although the use of EOs has increased over the years, adverse effects have limited their use. This review aims to address the regulatory standards for EO usage in food, techniques for delivery of EOs, essential oils commonly used to control pathogens and molds, and advances with new active compounds that overcome sensory effects for meat products, fresh fruits and vegetables, fruit and vegetable juices, seafood, dairy products, and other products. This review will show adverse sensory effects can be overcome in various products by the use of edible coatings containing encapsulated EOs to facilitate the controlled release of EOs. Depending on the method of cooking, the food product has been shown to mask flavors associated with EOs. In addition, using active packaging materials can decrease the diffusion rate of the EOs, thus controlling undesirable flavor characteristics while still preserving or prolonging the shelf life of food. The use of encapsulation in packaging film can control the release of volatile or active ingredients. Further, use of EOs in the vapor phase allows for contact indirectly, and use of nanoemulsion, coating, and film wrap allows for the controlled release of the EOs. Research has also shown that combining EOs can prevent adverse sensory effects. Essential oils continue to serve as a very beneficial way of controlling undesirable microorganisms in food systems.

Effects of ε-polylysine and chitooligosaccharide Maillard reaction products on quality of refrigerated sea bass fillets

BACKGROUND

The Maillard reaction is a promising and safe method for obtaining chitooligosaccharide conjugates with proteins or peptides as food preservatives. This study aims to investigate the moisture state, physicochemical properties, and shelf-life of sea bass fillets treated with ε-polylysine (ε-PL) and chitooligosaccharides (COS), which are Maillard reaction products (LC-MRPs), during refrigerated storage.

RESULTS

The results of microbiological analysis and confocal laser scanning microscope (CLSM) revealed that LC-MRPs could retard microbial growth effectively. Compared with control, other treated groups could strongly retard the increase in the thiobarbituric acid (TBA) value, the K-value and the total volatile basic nitrogen (TVB-N) value, and also inhibited the softening of texture and the accumulation of biogenic amines in fish. The results of low-field nuclear magnetic resonance (LF-NMR) and magnetic resonance imaging (MRI) indicate that LC-MRPs could delay the water migration of fillets and increase water holding capacity (WHC). Through sensory evaluation, the application of LC-MRPs increased the shelf-life of refrigerated sea bass fillets for another 9 days.

CONCLUSION

Maillard reaction products derived from chitooligosaccharides and ε-polylysine have strong potential for preserving sea bass. © 2022 Society of Chemical Industry.

Recent development in the preservation effect of lactic acid bacteria and essential oils on chicken and seafood products

Chicken and seafood are highly perishable owing to the higher moisture and unsaturated fatty acids content which make them more prone to oxidation and microbial growth. In order to preserve the nutritional quality and extend the shelf-life of such products, consumers now prefer chemical-free alternatives, such as lactic acid bacteria (LAB) and essential oils (EOs), which exert a bio-preservative effect as antimicrobial and antioxidant compounds. This review will provide in-depth information about the properties and main mechanisms of oxidation and microbial spoilage in chicken and seafood. Furthermore, the basic chemistry and mode of action of LAB and EOs will be discussed to shed light on their successful application in chicken and seafood products. Metabolites of LAB and EOs, either alone or in combination, inhibit or retard lipid oxidation and microbial growth by virtue of their principal constituents and bioactive compounds including phenolic compounds and organic acids (lactic acid, propionic acid, and acetic acid) and others. Therefore, the application of LAB and EOs is widely recognized to extend the shelf-life of chicken and seafood products naturally without altering their functional and physicochemical properties. However, the incorporation of any of these agents requires the optimization steps necessary to avoid undesirable sensory changes. In addition, toxicity risks associated with EOs also demand the regularization of an optimum dose for their inclusion in the products.

Impact of microencapsulated Ziziphora tenuior essential oil and orange fiber as natural-functional additives on chemical and microbial qualities of cooked beef sausage

The aim of the current study was to investigate the suitability of Ziziphora tenuior essential oil (ZEO) as a preservative. For this purpose, the effect of free and microencapsulated ZEO, combined with orange fiber, was determined on the chemical and microbial qualities of cooked beef sausage. In this study, modified starch was used for encapsulation of essential oil, and subsequently, 0.5% ZEO and 1% orange fiber were used for preparing cooked beef sausages during 60 days of storage at 4°C. To assess the microbial quality of samples, total viable count (TVC), psychrophilic count (PSY), and lactic acid bacteria (LAB) were analyzed. Furthermore, peroxide value (PV) and thiobarbituric acid reactive substances (TBARS) were tested to examine lipid oxidation. The most components of ZEO were pulegone (47.12%), isomenthone (14.57%), and 1,8-cineole (12.84%) according to GC-MS analysis. The reducing power, DPPH radical scavenging activity, MIC, and MBC of ZEO were 16.44 (EC50), 8.36 (IC50), 0.625-2.5, and 1.25-5 mg/ml, respectively. Moreover, sausage containing 0.5% microencapsulated ZEO in combination with 1% orange fiber showed the best results with the following values (p ≤ .05): TVC (3.69 log CFU/g), PSY (3.51 log CFU/g), LAB (3.1 log CFU/g), PV (10.41 meq/kg lipid), and TBARS (3.1 mg MDA/kg). This is due to the antimicrobial and antioxidant properties of microencapsulated essential oil. Therefore, the results of the present study can be applied in the meat industries as a new natural preservation method.

The Future Packaging of the Food Industry: The Development and Characterization of Innovative Biobased Materials with Essential Oils Added

The need to replace conventional, usually single-use, packaging materials, so important for the future of resources and of the environment, has propelled research towards the development of packaging-based on biopolymers, fully biodegradable and even edible. The current study furthers the research on development of such films and tests the modification of the properties of the previously developed biopolymeric material, by adding 10, respectively 20% w/v essential oils of lemon, grapefruit, orange, cinnamon, clove, mint, ginger, eucalypt, and chamomile. Films with a thickness between 53 and 102 µm were obtained, with a roughness ranging between 147 and 366 nm. Most films had a water activity index significantly below what is required for microorganism growth, as low as 0.27, while all essential oils induced microbial growth reduction or 100% inhibition. Tested for the evaluation of physical, optical, microbiological or solubility properties, all the films with the addition of essential oil in the composition showed improved properties compared to the control sample.

Effects of Sodium Alginate Edible Coating with Cinnamon Essential Oil Nanocapsules and Nisin on Quality and Shelf Life of Beef Slices during Refrigeration

ABSTRACT

The effects of a new edible sodium alginate (SA) coating incorporating cinnamon essential oil nanocapsules (CEO-NPs) and nisin were investigated with beef slices in refrigerated storage for 15 days. All beef samples were analyzed for physicochemical properties (pH, weight loss, and total volatile base nitrogen) and antimicrobial activity against total bacteria. Changes in color parameters and sensory attributes of all beef samples also were evaluated. Incorporation of the complex of CEO-NPs and nisin into the SA coating retarded the growth of microorganisms and reduced lipid oxidation, as determined by pH, total volatile base nitrogen, and total bacteria counts. This treatment also extended the shelf life of beef slices to 15 days. The SA coating with CEO-NPs and nisin significantly reduced weight loss and improved color, odor, texture, and purge quality of the beef samples. These results suggest that treatment with the SA coating enriched with CEO-NPs and nisin can significantly retard the deterioration of beef slices, and the complex of CEO-NPs and nisin can improve antioxidant, antibacterial, and sensory properties of the SA coating. This new edible coating could be useful for preserving beef slices.

HIGHLIGHTS

Application of Xanthan-Gum-Based Edible Coating Incorporated with Litsea cubeba Essential Oil Nanoliposomes in Salmon Preservation

Salmon is prone to be contaminated by Vibrio parahaemolyticus (V. parahaemolyticus), leading to the deterioration of salmon quality and the occurrence of food-borne diseases. In this study, we aimed to develop a novel xanthan-gum-based edible coating embedded with nano-encapsulated Litsea cubeba essential oil (LC-EO) for salmon preservation at 4 °C. First, the results of the growth curves and scanning electron microscopy (SEM) showed that LC-EO displayed potent antibacterial activity against V. parahaemolyticus; the optimal concentration of LC-EO in the liposomes was 5 mg/mL, and the maximal encapsulation efficiency (EE) was 37.8%. The particle size, polydispersity coefficient (PDI), and zeta potential of the liposomes were 168.10 nm, 0.250, and −32.14 mV, respectively. The rheological test results of xanthan-gum-based edible coatings incorporating liposomes showed that the prepared coating was suitable for applying on food surfaces. The results in the challenge test at 4 °C demonstrated that the treatment of 1:3 (liposome: xanthan gum, v/v) coating performed the best preservative properties, the coating treatment delayed the oxidation of salmon, and controlled the growth of V. parahaemolyticus. These findings suggest that the coatings formulated in this study could be used as a promising approach to control V. parahaemolyticus contamination and maintain salmon quality.

Antiosteoporosis Studies of 20 Medicine Food Homology Plants Containing Quercetin, Rutin, and Kaempferol: TCM Characteristics, In Vivo and In Vitro Activities, Potential Mechanisms, and Food Functions

Dietary nutraceutical compounds have been evidenced as backbone for bone health in recent years. It is reported that medicine food homology (MFH) plants have multiple nutraceutical compounds. Based on our literature research, 20 MFH plants caught our attention because they contain three popular antiosteoporosis compounds simultaneously: quercetin, rutin, and kaempferol. According to traditional Chinese medicine (TCM), their characteristics including natures, flavors, attributive to meridian tropism, and efficacies were listed. The relationships between TCM efficacies, such as “heat clearing,” “tonic,” and “the interior warming,” and antiosteoporosis pharmacological actions such as antioxidant and immune regulation were discussed. The in vivo antiosteoporosis effects of the 20 MFH plants were summarized. The in vitro antiosteoporosis activities and related mechanisms of the 20 plants and quercetin, rutin, kaempferol were detailed. The TGF-β-Smad signaling, fibroblast growth factor, and Wnt/β-catenin signaling on bone formation and the RANKL signaling, NF-κB signaling, and macrophage-colony-stimulating factor on bone resorption were identified. From food point, these 20 MFH plants could be classified as condiment, vegetable, fruit, tea and related products, beverage, etc. Based on the above discussion, these 20 MFH plants could be used as daily food supplements for the prevention and treatment against osteoporosis.

Investigation of the chemical properties of Mentha pulegium essential oil and its application in Ocimum basilicum seed mucilage edible coating for extending the quality and shelf life of veal stored in refrigerator (4°C)

Nowadays, the tendency toward the application of natural preservatives to extent the shelf life of food products has grown. The purpose of the present research was to evaluate the effect of the basil seed mucilage (BSM)-based edible coating containing different concentrations of Mentha pulegium essential oil (MPEO) on the shelf life of the veal stored at refrigerator temperature. Firstly, the chemical composition and functional groups of MPEO were detected through gas chromatography-mass spectrometry (GC-MS) and Fourier transform infrared spectroscopy (FTIR). Then, the BSM-based edible coatings containing 0%, 0.5%, 1%, 1.5%, and 2% MPEO were prepared, and the veal samples were coated with them. The physicochemical, microbial, and sensory properties of the samples were investigated during the 9-day storage period at 4°C. Twenty-five compounds were detected in MPEO with limonene being the major one (28.44%). The results revealed that the lightness, hardness, and moisture content of the samples decreased during storage. The coating containing the essential oil could properly restrain the rise in pH, peroxide value (PV), and thiobarbituric acid value (TBA). Based on microbial analyses, the shelf life of the coated sample without the essential oil and those containing 0.5%, 1%, 1.5%, and 2% of the essential oil were, respectively, extended up to 3, 6, 9, 9, and 9 days relative to the control. Moreover, the coating containing the essential oil produced no unfavorable effect on the sensory properties of the meat samples. In conclusion, the BSM-based edible coating containing different concentrations of MPEO can be applied as a natural preservative to enhance the resistance of meat products against microbial spoilage and fat oxidation.

Quality of Physalis peruviana fruits coated with pectin and pectin reinforced with nanocellulose from P. peruviana calyces

Physalis peruviana is marketed without its calyx, which generates byproducts and a decrease in the shelf life of these fruits. The aim of this study was to evaluate the effect of edible pectin-coatings reinforced with nanocellulose from calyx on the physical-chemical and physiological parameters of P. peruviana fruits during refrigerated storage (5 °C) for ten days. The nanocellulose extraction was carried out using a combined extraction method (chemical procedures and ultrasound radiation). The characterization of the fibers showed that the maximum degradation temperatures ranged between 300 and 311 °C. The SEM analysis revealed the presence of fibers after the chemical treatment. The removal of lignin and hemicellulose was validated using Fourier Transform Infra Red (FTIR) spectroscopy. The results showed that the fruits treated with pectin and pectin reinforced with nanocellulose at 0.5 % (w/w) had an adequate visual appearance and showed a minor color change (ΔE of 19.04 and 21.04, respectively) and the highest retention of L∗ during storage. Although the addition of nanocellulose at 0.5% presented the lowest respiratory rate (29.60 mgCO₂/kg h), the treatment with pectin offered the least weight loss and showed the highest firmness retention at the end of storage. Thus, the edible pectin-coating may be useful for improving the postharvest quality and storage life of fresh P. peruviana fruit. Nanocellulose from P. peruviana calyces can be used under the concept of a circular economy; although, its use as a reinforcement of pectin showed some limitations.

Effects of gallic acid combined with epsilon-polylysine hydrochloride incorporated in a pullulan-CMC edible coating on the storage quality of sea bass

The effects of edbile coatings, based on pullulan and sodium carboxymethylcellulose (PUL-CMC) with gallic acid (GA) and/or ε-polylysine hydrochloride (PL), on the quality of sea bass (Lateolabrax maculatus) fillets during storage at 4 °C for 20 days were assessed in this study. Total viable counts (TVC), thiobarbituric acid (TBA), pH value, total volatile basic nitrogen (TVB-N), water holding capacity (WHC), water migration, texture profiles, and electronic nose results were measured at five day intervals. The results showed that treatments with PUL-CMC-GA, PUL-CMC-PL, and PUL-CMC-GA-PL coatings retarded the increase of the TVC, TBA, pH, and TVB-N value when compared with the results of the control group. These coatings significantly maintained the content of immobile water, WHC, texture and flavor properties of the fish. In addition, use of PUL-CMC-GA-PL was more effective than use of PUL-CMC-GA and PUL-CMC-PL. The TVC, TVB-N, and pH in the PUL-CMC-GA-PL group were all lower than those in the other groups during the whole storage time. The TBA value in the PUL-CMC-GA-PL group remained below 0.7 mg malonaldehyde (MDA) per kg at 20 d, which was extended by 10 d when compared with the values for the other groups. The WHC in PUL-CMC-GA-PL only decreased by 6.53% during 20 d of storage. The results indicated that GA combined with PL had a synergistic effect on improving the preservation properties of PUL-CMC, which could inhibit lipid oxidation, protein degradation and microbial growth, and maintain better texture characteristics during the storage of sea bass fillets.

Improving the Storability of Cod Fish-Burgers According to the Zero-Waste Approach

This research explored the potential of the zero-waste concept in relation to the storability of fresh food products. In particular, the prickly pear (Opuntia ficus-indica) peel (usually perceived as a by-product) and the pulp were dehydrated, reduced in powder, and used as food additives to slow down the growth of the main spoilage microorganisms of fresh cod fish burgers. The proportion between peel and pulp powder was such as to respect the zero-waste concept. The antibacterial activity of the peel and pulp in proper proportion was first assessed by means of an in vitro test against target microorganisms. Then, the active powder was added at three concentrations (i.e., 2.5 g, 7.5 g, and 12.5 g) to cod fish burgers to assess its effectiveness in slowing down the microbial and sensory quality decay of burgers stored at 4 °C. The results from the in vitro test showed that both the peel and pulp were effective in delaying microbial growth. The subsequent storability test substantially confirmed the in vitro test results. In fact, a significant reduction in growth rate of the main fish spoilage microorganisms (i.e., Pseudomonas spp., psychrotrophic bacteria, and psychrotolerant and heat-labile aerobic bacteria) was observed during 16 days of refrigerated storage. As expected, the antimicrobial effectiveness of powder increased as its concentration increased. Surprisingly, its addition did not affect the sensory quality of fish. Moreover, it was proven that this active powder can improve the fish sensory quality during the storage period.

Shelf-Life Extension of Large Yellow Croaker (Larimichthys crocea) Using Active Coatings Containing Lemon Verbena (Lippa citriodora Kunth.) Essential Oil

Active coating could improve the fish quality and extend the shelf life. This study investigates the effect of locust bean gum (LBG) and sodium alginate (SA) active coatings containing lemon verbena (Lippa citriodora Kunth.) essential oil (LVEO) emulsions on microbiological, physicochemical and organoleptic evaluation of large yellow croaker (Larimichthys crocea) samples during refrigerated storage at 4°C. Results showed that LBG-SA coatings incorporated with 0.30 or 0.60% LVEO emulsions significantly inhibited the growth of mesophile bacteria, Pseudomonas spp., H₂S-producing bacteria, lactic acid bacteria (LAB) and psychrophilic bacteria, and reduce the productions of trimethylamine (TMA), total volatile basic nitrogen (TVB-N) and ATP-related compounds. Further, the LVEO treatments also retarded the water migration and maintained the organoleptic evaluation results of large yellow croaker during storage at 4°C. In conclusion, the LBG-SA active coatings incorporated with LVEO emulsions maintained the quality and extended the shelf life of large yellow croaker during refrigerated storage.

Shelf-Life Extension of Refrigerated Turbot (Scophthalmus maximus) by Using Weakly Acidic Electrolyzed Water and Active Coatings Containing Daphnetin Emulsions

This research was to investigate the effect of weakly acidic electrolytic water (WAEW) treatments combining with the locust bean gum (LBG) and sodium alginate (SA) active coatings, containing daphnetin emulsions on microbiological, physicochemical, and sensory changes of turbot (Scophthalmus maximus) during refrigerated storage at 4°C for 24 days. Results showed that WAEW, together with LBG-SA coatings containing daphnetin emulsions treatments, could significantly lower the total viable count (TVC), H₂S-producing bacteria, pseudomonas spp., and psychrotrophic bacteria counts, and inhibit the productions of off-flavor compounds, including the total volatile basic nitrogen (TVB-N), inosine (HxR), and hypoxanthine (Hx). Furthermore, the treatments also prevented textural deterioration, delayed water migration, and had higher organoleptic evaluation results. Therefore, WAEW, together with LBG-SA coatings, containing daphnetin emulsions treatments, had the potential to improve the quality of turbot during refrigerated storage.

A sodium alginate bilayer coating incorporated with green propolis extract as a powerful tool to extend Colossoma macropomum fillet shelf-life

Fish deterioration imposes great economic losses and serious human health hazards. The objective of this work was to evaluate the effect of a sodium alginate bilayer coating incorporated to the green propolis extract in shelf-life, physical-chemical properties, microbiological properties and sensory acceptance of Colossoma macropomum fillets. Additionally, the chemical composition, along with the antioxidant and antibacterial activities of Brazilian green propolis extract (GPE) were investigated. GPE showed promising antioxidant and antibacterial activities. Twenty-seven metabolites were identified by gas chromatography (GC-MS), which mainly comprised terpenoids (52.14%). Cyclolaudenol was the major constituent of the GPE and it is described for the first time in green propolis extracts. C. macropomum fillets treated with the sodium alginate bilayer coating showed high sensory acceptance, reduced microbial deterioration and extended shelf-life (up to 11 days) during cold storage. Taken together, these results show that GPE can be a great alternative of a natural preservative for fish coating.

Antiparasitic and Antibacterial Functionality of Essential Oils: An Alternative Approach for Sustainable Aquaculture

Using synthetic antibiotics/chemicals for infectious bacterial pathogens and parasitic disease control causes beneficial microbial killing, produces multi-drug resistant pathogens, and residual antibiotic impacts in humans are the major threats to aquaculture sustainability. Applications of herbal products to combat microbial and parasitic diseases are considered as alternative approaches for sustainable aquaculture. Essential oils (EOs) are the secondary metabolites of medicinal plants that possess bioactive compounds like terpens, terpenoids, phenylpropenes, and isothiocyanates with synergistic relationship among these compounds. The hydrophobic compounds of EOs can penetrate the bacterial and parasitic cells and cause cell deformities and organelles dysfunctions. Dietary supplementation of EOs also modulate growth, immunity, and infectious disease resistance in aquatic organisms. Published research reports also demonstrated EOs effectiveness against Ichthyophthirius multifiliis, Gyrodactylus sp., Euclinostomum heterostomum, and other parasites both in vivo and in vitro. Moreover, different infectious fish pathogenic bacteria like Aeromonas salmonicida, Vibrio harveyi, and Streptococcus agalactiae destruction was confirmed by plant originated EOs. However, no research was conducted to confirm the mechanism of action or pathway identification of EOs to combat aquatic parasites and disease-causing microbes. This review aims to explore the effectiveness of EOs against fish parasites and pathogenic bacteria as an environment-friendly phytotherapeutic in the aquaculture industry. Moreover, research gaps and future approaches to use EOs for sustainable aquaculture practice are also postulated.

Edible flower essential oils: A review of chemical compositions, bioactivities, safety and applications in food preservation

In the context of consumers' growing concerns and boycotts of artificial and harmful chemicals, satisfying the demands for good-quality food products possessing clean and safe images is a challenge for food industry. Due to natural and avirulent images, various bioactivities as well as potentials to be used as safer substitutes for chemical preservatives, flower essential oils (EOs) have aroused increasing interests in the recent past. Many literatures have verified the biological activities of flower EOs, and have given high value to the preservative potentials of flower EOs in food systems. In this work, a review is done on the most recent publications associating the chemical constituents, bioactivities (antibacterial, antifungal, antioxidant and anti-pest abilities) and safety of flower EOs. The effects of flower EOs on food flavor are also discussed. Finally, the current combined preservation applications of flower EOs and other technologies are summarized.

Synergistic Antimicrobial Effectiveness of Plant Essential Oil and Its Application in Seafood Preservation: A Review

The synergistic potential of plant essential oils (EOs) with other conventional and non-conventional antimicrobial agents is a promising strategy for increasing antimicrobial efficacy and controlling foodborne pathogens. Spoilage microorganisms are one of main concerns of seafood products, while the prevention of seafood spoilage principally requires exclusion or inactivation of microbial activity. This review provides a comprehensive overview of recent studies on the synergistic antimicrobial effect of EOs combined with other available chemicals (such as antibiotics, organic acids, and plant extracts) or physical methods (such as high hydrostatic pressure, irradiation, and vacuum-packaging) utilized to reduce the growth of foodborne pathogens and/or to extend the shelf-life of seafood products. This review highlights the synergistic ability of EOs when used as a seafood preservative, discovering the possible routes of the combined techniques for the development of a novel seafood preservation strategy.

The impact of Qodume Shirazi seed mucilage-based edible coating containing lavender essential oil on the quality enhancement and shelf life improvement of fresh ostrich meat: An experimental and modeling study

Today, food consumers prefer to use the foods that contain natural preservatives. The purpose of this study was to investigate the effect of Qodume Shirazi seed mucilage (QSSM) and lavender essential oil (LO) on the preservation of ostrich meat during cold storage. The chemical compounds of LO were identified through gas chromatography-mass spectrometry (GC/MS). The ostrich meat samples were coated with the mucilage containing the essential oil at concentrations of 0%, 0.5%, 1%, 1.5%, and 2%, v/v. The control and the coated ostrich meat samples were kept at 4°C and analyzed for microbiological (total viable count, psychrotrophic count, Escherichia coli, Staphylococcus aureus, coliforms, and fungi), physicochemical (moisture content, pH, texture, and color parameters), and sensorial (odor, color, and total acceptance) characteristics during 9 days of storage. GC/MS identified 12 compounds in the essential oil, among which linalool was the major one (43.3%). The lightness (L* value) and hardness of all the ostrich meat samples were reduced during the storage. From a microbiological point of view, the cold storage duration for the control and the coated sample without the essential oil was only 3 days, while for coated samples containing 0.5%, 1%, 1.5%, and 2% essential oil, it was 3, 3, 6, and 9 days, respectively. The coated ostrich meat containing 2% LO had an appropriate quality with an expanded shelf life. The results showed that neural network with 10 neurons in the hidden layer had the lowest mean squared error and mean absolute error and the highest correlation coefficient for predicting the quality and microbial properties of the coated meat samples during storage.

Potential of Propolis Extract as a Natural Antioxidant and Antimicrobial in Gelatin Films Applied to Rainbow Trout (Oncorhynchus mykiss) Fillets

Usage of edible films and coatings alone or incorporated with natural extracts are a new approach to preservation and packaging of food. In this study, therefore, the microbiological, chemical quality, and sensorial changes of rainbow trout fillets coated with gelatin films supplemented with propolis extract (PE) (2, 8, 16%), as a source of polyphenols, were determined during 15 days of refrigerated storage (4 ± 1 °C). According to peroxide value (PV) and thiobarbituric acid reactive substances (TBARS) assays, lipid oxidation was delayed in the fillets coated with gelatin films incorporated with PE comparing with the control and gelatin-coated (without PE) fillets. The total volatile basic nitrogen (TVB-N) value of rainbow trout fillets showed an increase in all groups at the end of storage, observing the lowest values in the fillets coated with gelatin films prepared with 16% PE. Gelatin films enriched with PE had great inhibitory effects on the microbial growth in rainbow trout fillets. The addition of PE enhanced the effectiveness of gelatin films and delayed the lipid oxidation and sensory and microbial deterioration in trout fillets coated with these films. Thus, PE can be recommended to be used as a natural antioxidant and antimicrobial additive with gelatin films to maintain rainbow trout fillet quality.

Edible Coating and Pulsed Light to Increase the Shelf Life of Food Products

The application of edible coatings (EC) in combination with pulsed light (PL) treatments represents an emerging approach for extending the shelf life of highly perishable but high value-added products, such as fresh-cut fruits and vegetables. The surface of these products would benefit from the protective effects of ECs and the PL decontamination capability. This review describes in detail the fundamentals of both EC and PL, focusing on the food engineering principles in the formulation and application of EC and the delivery of efficient PL treatments and the technological aspects related to the food characterization following these treatments and discussing the implementation of the two technologies, individually or in combination. The advantages of the combination of EC and PL are extensively discussed emphasizing the potential benefits that may be derived from their combination when preserving perishable foods. The downsides of combining EC and PL are also presented, with specific reference to the potential EC degradation when exposed to PL treatments and the screening effect of PL transmittance through the coating layer. Finally, the potential applications of the combined treatments to food products are highlighted, comparatively presenting the treatment conditions and the product shelf-life improvement.