Fish Fillets Research Articles

Development and characterization of a double-layer smart packaging system consisting of polyvinyl alcohol electrospun nanofibers and gelatin film for fish fillet

This study aimed to develop a double-layer film composed of an intelligent, gelatin-based film integrated with active polyvinyl alcohol electrospun nanofibers (PVANFs). Eggplant skin extract (ESE), a colorimetric indicator, was incorporated into the gelatin-based film at varying concentrations ranging from 0 % to 8 % w/w. The gelatin film containing 8 % ESE was identified as the optimal formulation based on its superior color indication, water barrier, and mechanical properties. Savory essential oil (SEO)-loaded PVANFs were electrospun onto the optimized gelatin film to fabricate the double-layer film. Analysis of the chemical and crystalline structures and the double-layer film's thermal properties confirmed the gelatin film's physical integration with PVANFs. Morphological examination revealed a smooth surface on the film and a uniform fibrillar structure within the PVANFs. Furthermore, the developed double-layer film effectively detected spoilage in trout fish while controlling pH, oxidation, and microbial changes during storage.

Antioxidant Activity of Rosemary Oil and Olive Oil and its Impact on the Shelf Life of Fish Fillets

Antioxidant Activity of Rosemary Oil and Olive Oil and its Impact on the Shelf Life of Fish Fillets

Anthocyanin modified by chondroitin sulphate and tannic acid improved the quality-indicating properties of gelatin-based intelligent film

A highly pH-responsive gelatin film incorporating purple cabbage anthocyanin (PCA) and chondroitin sulphate (CS)/tannic acid (TA) was developed. Co-pigmentation of PCA via CS/TA improved its photothermal stability and visibility of color change in gelatin film. The morphological and structural properties of CS-PCA and TA-PCA films revealed that a more stable network was formed as new hydrogen bonds were generated by the co-pigmentation. Meanwhile, the co-pigmentation improved film's mechanical and hydrophobic properties, expressed as higher tensile strength (16.65 and 17.97 Mpa) and lower water vapor permeability (1.45 and 1.41) in CS-PCA and TA-PCA films, compared to PCA film. CS-PCA and TA-PCA films showed distinct color transitions for chilled fish fillets during storage. Total color difference (ΔE) of CS-PCA and TA-PCA films correlated well with the deterioration indexes of total volatile base nitrogen (TVB-N). All the results provided a novel pH-sensitive intelligent packaging strategy by co-pigmenting CS/TA with PCA for freshness monitoring.

Double layer packaging based on active black chickpea protein isolate electrospun nanofibers and intelligent salep film containing black chickpea peel anthocyanins for seafood products

In this study, a double-layer active and intelligent packaging system was developed based on two main natural macromolecules i.e. protein and carbohydrate with green perspective. Firstly, the salep-based films containing different concentrations (0–8 % w/w) of the inclusion complex of β-cyclodextrin/black chickpea anthocyanins (βCD/BCPA) were produced. The salep film containing 8 % of βCD/BCPA complex was specified as the optimized film sample based on its performance as a color indicator. The electrospinning of black chickpea protein isolate nanofibers (BCPI NFs) containing citral nanoliposomes (NLPs) was done on the optimized salep film. The cross-sectional field emission scanning electron microscopy approved the creation of double-layer structure of the developed film. The study of chemical and crystalline structure, as well as the thermal properties of the film exhibited the physical attachment of BCPI electrospun NFs on salep film. The effectiveness of the developed system was studied in detection of spoilage and increasing the shelf life of seafood products, including shrimp and fish fillet. The performance of the intelligent layer in detection of freshness/spoilage was acceptable for both seafood products. In addition, the active layer of the film controlled the changes of pH, total volatile basic nitrogen, oxidation, and microbial load in samples during storage time.

Microbiota diversity of three Brazilian native fishes during ice and frozen storage

This study aimed to assess the bacterial microbiota involved in the spoilage of pacu (Piaractus mesopotamics), patinga (female Piaractus mesopotamics x male Piaractus brachypomus), and tambacu (female Colossoma macropomum × male Piaractus mesopotamics) during ice and frozen storage. Changes in the microbiota of three fish species (N = 22) during storage were studied through 16S rRNA amplicon-based sequencing and correlated with volatile organic compounds (VOCs) and metabolites assessed by nuclear magnetic resonance (NMR). Storage conditions (time and temperature) affected the microbiota diversity in all fish samples. Fish microbiota comprised mainly of Pseudomonas sp., Brochothrix sp., Acinetobacter sp., Bacillus sp., Lactiplantibacillus sp., Kocuria sp., and Enterococcus sp. The relative abundance of Kocuria, P. fragi, L. plantarum, Enterococcus, and Acinetobacter was positively correlated with the metabolic pathways of ether lipid metabolism while B. thermosphacta and P. fragi were correlated with metabolic pathways involved in amino acid metabolism. P. fragi was the most prevalent spoilage bacteria in both storage conditions (ice and frozen), followed by B. thermosphacta. Moreover, the relative abundance of identified Bacillus strains in fish samples stored in ice was positively correlated with the production of VOCs (1-hexanol, nonanal, octenol, and 2-ethyl-1-hexanol) associated with off-flavors. 1H NMR analysis confirmed that amino acids, acetic acid, and ATP degradation products increase over (ice) storage, and therefore considered chemical spoilage index of fish fillets.

Comparative study of dietary selenium sources on gilthead seabream (Sparus aurata): Growth, nutrient utilization, stress response and final product quality

Selenium (Se) is a crucial trace mineral in human nutrition, known for its various health benefits, including the enhancement of antioxidant defenses. Enrichment of fish fillets with Se is seen as an interesting strategy to reduce the risk of Se deficiency in human diets. While inorganic sources have been traditionally used to supplement Se in fish diets, organic Se forms have demonstrated superior bioavailability and efficacy in managing oxidative stress and tissue retention rates compared to their inorganic counterparts.The main objective of this study was to assess the performance, stress resistance, and product quality of gilthead seabream (Sparus aurata) in response to diets supplemented with 0.2 mg kg−1 of Na2SeO3 (CTRL), Zn-L-SeMet (AVSe) or OH-Se-Met (ORGSe), complying therefore with the European Food Safety Agency (EFSA) maximum allowed supplementation of organic Se (0.2 mg kg−1). Diets were formulated to be similar in their protein (48% DM) and lipid content (17% DM), and hand-fed to apparent satiety to quadruplicate groups of 20 fish (initial body weight ∼ 75 g) gilthead seabream juveniles for 137 days. Fish were kept in a recirculating saltwater system (salinity 35‰, 22 ± 1 °C) until they reached commercial size (>250 g). At the end of the growth trial, all fish were individually weighed and measured, with 4 fish per tank sampled for whole-body composition analysis. Fillet yield, muscle lipid and mineral composition, and hepatic oxidative stress indicators were assessed (n = 12). Lipid peroxidation, muscle pH, water-holding capacity (WHC), color, and texture were evaluated on days 7 and 14 (n = 8), while sensory analysis was conducted on 20 fish. Additionally, 12 fish per treatment were subjected to overcrowding (100 kg m−3) for 5 min and air exposure for 1 min. After a 1-h recovery period, plasma and liver samples were collected from these fish, and results were compared to those of the non-stress group. All diets yielded equivalent growth performance, ensuring low feed conversion ratio. Fish fed the AVSe diet exhibited higher whole-body protein content compared to those fed the CTRL diet. Regarding mineral utilization, increased Se retention and gain in fish fed AVSe and ORGSe diets led to higher Se content in these fish compared to the CTRL. Additionally, the AVSe diet has also resulted in significantly increased Se deposition in the muscle compared to the other tested Se sources, contributing with 34% of the Se Daily Recommended Intake (DRI). The assessed flesh quality parameters and overall consumer acceptance did not reveal significant differences among the groups. Exposure to an acute stress was found to decrease the activities of Glutathione reductase and glutathione peroxidase, which in turn has increased the level of oxidized glutathione, particularly in the AVSe group. Compared to OH-Se-Met and Na2SeO3, Zn-L-SeMet was more effective in promoting response to stress and nutritional value of gilthead seabream as an important source of protein and Se in human diet.

Quantitative PCR assays as a monitoring tool for bacterial genera in fresh fish fillets

Fresh fish fillets are a valuable but highly perishable food, and their rapid microbial deterioration is a drawback for food safety and sustainability of aquaculture, food and retail industries. Quantitative PCR (qPCR) assays based on 16S rRNA gene (16S) sequences were developed for the most abundant bacteria genera detected by metagenomics in fresh or processed fish fillets. The efficiency and specificity of six qPCR assays (for 16S of all bacteria or genera Shewanella, Pseudomonas, Carnobacterium, Janthinobacterium and Massilia) was verified using in silico predictions, cloning, sequencing and phylogenetic analyses of amplicons obtained from refrigerated control or high-pressure processed (HPP) European sea bass (Dicentrarchus labrax) fillets. In HPP sea bass fillets, significant decreases in total bacteria 16S and of Shewanella, Pseudomonas, Carnobacterium and Janthinobacterium 16S compared to control fillets were confirmed by qPCR, after 11 days of refrigerated storage. The qPCR assays were successfully applied to monitor microbial contamination during refrigerated storage of fresh fillets from commercial (retail) sea bass and gilthead sea bream (Sparus aurata). Significant increases in total bacterial and Shewanella, Pseudomonas, Carnobacterium and Janthinobacterium contamination were detected after 7–14 days. 16S copy number for total bacteria and the four target genera positively correlated with total viable counts using culture enumeration. 16S of Massilia, that is abundant in fresh fish fillets, did not significantly change during storage. The six validated qPCR assays developed are proposed as specific, sensitive, culture-independent methods for monitoring quality or processing outcomes for fish fillets during cold chain storage.

Assessing Per- and Polyfluoroalkyl Substances in Fish Fillet Using Non-Targeted Analyses.

Per- and polyfluoroalkyl substances (PFAS) are a class of thousands of man-made chemicals that are persistent and highly stable in the environment. Fish consumption has been identified as a key route of PFAS exposure for humans. However, routine fish monitoring targets only a handful of PFAS, and non-targeted analyses have largely only evaluated fish from heavily PFAS-impacted waters. Here, we evaluated PFAS in fish fillets from recreational and drinking water sources in central North Carolina to assess whether PFAS are present in these fillets that would not be detected by conventional targeted methods. We used liquid chromatography, ion mobility spectrometry, and mass spectrometry (LC-IMS-MS) to collect full scan feature data, performed suspect screening using an in-house library of 100 PFAS for high confidence feature identification, searched for additional PFAS features using non-targeted data analyses, and quantified perfluorooctanesulfonic acid (PFOS) in the fillet samples. A total of 36 PFAS were detected in the fish fillets, including 19 that would not be detected using common targeted methods, with a minimum of 6 and a maximum of 22 in individual fish. Median fillet PFOS levels were concerningly high at 11.6 to 42.3 ppb, and no significant correlation between PFOS levels and number of PFAS per fish was observed. Future PFAS monitoring in this region should target more of these 36 PFAS, and other regions not considered heavily PFAS contaminated should consider incorporating non-targeted analyses into ongoing fish monitoring studies.

The Concentration of Potentially Toxic Elements in Common Carp (Cyprinus carpio) in Fish: Systematic Review and Meta-Analysis and Dietary Health Risk Assessment.

Common carp (Cyprinus carpio) is one of the most consumed fish in the world and can be exposed to various forms of pollution, such as potential toxic elements (PTEs). Several studies have been conducted on the concentration of PTEs in common carp fish. The aims of the current study were to meta-analyze the concentration of PTEs in common carp fish and estimate human health risks in consumers. A search was conducted in international databases, including Scopus, PubMed, Science Direct, Web of Science, and Embase to retrieve papers up to January 20, 2024. The non-carcinogenic risk due to PTEs in fish fillets was calculated via the target hazard quotient (THQ), and the carcinogenic risk due to iAs in fish fillets was calculated via cancer risk (CR). The highest concentrations of Cu, methyl-Hg, and Ni were observed in the fillets of common carp fish. The non-carcinogenic risk was lower than 1 in all countries; hence, consuming common carp fish does not pose a non-carcinogenic risk. Adult consumers in Iraq were exposed to an unacceptable carcinogenic due to iAs in common carp fish. Hence, it is recommended that plans be conducted to reduce the concentration of PTEs in common carp fish in Iraq.

The Optimization of Aerobic Bacteria Inactivation in Tilapia (Oreochromis niloticus) Fillets using Micro-Nano Bubbles of Carbon Dioxide and Shelf-Life Extension

This study aims to examine the influence of NaOCl, NaCl and contact time on the inactivation of aerobic bacteria in tilapia fillets treated with micro-nano bubbles of CO2 (CO2 MNB) in a washing process of fish fillets, and compared to soaking with tap water and untreated fillets for their shelf-life extensions. Response surface methodology (RSM) with a central composite design was used to compare and predict of the inactivation effects. The fish fillets were soaked in a NaOCl solution before washing with a NaCl solution and CO2 MNB produced from an MNB generator system, maintaining the liquid temperature in the range of 4–7 °C for all experiments. According to the regression analysis from the experimental design, aerobic bacteria inactivation was reduced by 1.509 log CFU/g at 100 mg/L NaOCl, 10%w/v NaCl, and a contact time of 32 min with CO2 MNB. The experimental value of the reduction of aerobic bacteria by 1.503 ± 0.009 log CFU/g (before washing 5.623 log CFU/g; after washing 4.120 log CFU/g) was found after treatment under the aforementioned condition. The number of aerobic bacteria counted on the tilapia fillets treated with the upper condition after being stored at 4 ± 2 °C for 7 d was below the acceptable limits, but untreated and treated with tap water had bacteria counts exceeding the upper microbial limit (6 log CFU/g). The combined results showed that the NaOCl, NaCl solution and CO2 MNB treatment could extend the storage time by more than 7 d.

Preparation and properties of PCL coaxial electrospinning films with shell loaded with CEO and core coated LEO nanoemulsions

During storage and transportation, the reduction of microbial contamination and management of the exudation of fluids from the fish can effectively mitigate spoilage and degradation of fish fillets. In this work, the coaxial electrospinning films loaded with natural plant preservatives, namely laurel essential oil (LEO) and clove essential oil (CEO), were prepared by the coaxial electrospinning method synergistic with nanoemulsion techniques, and the hydrophilic preservation pads were prepared. The morphology of the film fiber is clear, without beads or damage, with fiber diameters falling within the 230–260 nm range. It has a distinct core–shell structure, exceptional thermal stability, and strong antibacterial and antioxidant properties. The core–shell structure of the fiber subtly regulates the release of preservatives and significantly improves the utilization efficiency. At the same time, the synergistic use of two essential oils can reduce the amount while amplifying their effectiveness. The pads significantly slowed down the increase of key indicators of spoilage, such as total viable count (TVC), pH, thiobarbituric acid reactive substances (TBA), and total volatile base nitrogen (TVB-N), during the storage of the fish fillets. Furthermore, the pads effectively slowed down the decline in water-holding capacity, the deterioration of textural qualities, and the negative changes in the microstructure of the fish muscle. Ultimately, the pads notably delayed the spoilage of fish fillets, extending their shelf life from 5 d to 9 d. The efficient utilization of biological preservatives in this film can provide technical support for the development of food preservation materials.

The individual and combined effect of DHA and high-fat diet on flesh quality, antioxidant capacity and myofiber characteristics of grass carp (Ctenopharyngodon idellus)

The impact of a high-fat diet (HFD) on the meat quality of farmed fish is a subject of considerable interest among researchers. While docosahexaenoic acid (DHA) is recognized for enhancing growth performance and muscle mass in fish, its potential to mitigate the adverse effects of HFD on meat quality remains uncertain. This study examined the nutritional value, textural properties, and muscle characteristics of grass carp (Ctenopharyngodon idellus) fed varying levels of DHA (0.0%, 0.5%, and 1.0%) under either a regular fat diet (5.0% lipid) or an HFD (10.0% lipid) for a period of eight weeks. Results indicated that the addition of DHA to both the normal fat diet and HFD significantly improved the nutritional and sensory qualities of fish fillets, increasing crude protein, polyunsaturated fatty acid (PUFA), and collagen content while preserving optimal muscle hardness and pH levels. The HFD group exhibited diminished antioxidant capacity, reduced sarcomere length, and mitochondrial structural damage, all effectively ameliorated through DHA supplementation. Moreover, dietary DHA supplementation at both lipid levels upregulated the expression of genes associated with myogenesis and protein synthesis. A two-way ANOVA revealed significant interactions between dietary DHA and lipids, influencing muscle pH, fatty acid composition, myofiber characteristics, antioxidant capacity, and gene expression related to muscle growth and protein synthesis. In conclusion, DHA supplementation can effectively mitigate the deterioration of fish flesh quality induced by HFD.

Fish Fillet Analogue Using Formulation Based on Mushroom (Pleurotus ostreatus) and Enzymatic Treatment: Texture, Sensory, Aromatic Profile and Physicochemical Characterization.

The growing demand for alternative sources of non-animal proteins has stimulated research in this area. Mushrooms show potential in the innovation of plant-based food products. In this study, the aim was to develop prototype fish fillets analogues from Pleurotus ostreatus mushrooms applying enzymatic treatment (β-glucanase and transglutaminase-TG). A Plackett-Burman 20 experimental design was used to optimize forty variables. Oat flour (OF) exerted a positive effect on the hardness and gumminess texture parameters but a negative effect on cohesiveness and resilience. Soy protein isolate (SPI) exhibited a positive effect on elasticity, gumminess and chewiness, while acacia gum had a negative effect on elasticity, cohesiveness and resilience. After sensory analysis the assay with 1% cassava starch, 5% OF, 5% SPI, 0.1% transglutaminase (240 min/5 °C), 1% coconut oil, 1% soybean oil, 0.2% sodium tripolyphosphate, 0.6% β-glucanase (80 °C/10 min) and without β-glucanase inactivation was found to exhibit greater similarity to fish fillet. The classes hydrocarbons, alcohols and aldehydes are the predominant ones in aromatic profile analysis by chromatography and electronic nose. It is concluded that a mushroom-based analogue of fish fillet can be prepared using enzymatic treatment with TG.

Production of fish fillet analogues using novel fish muscle cell powder and sodium alginate-κ-carrageenan based bio-ink

Cellular aquaculture has emerged as a promising technology to address the challenges associated with traditional fishing and aquaculture practices. This study focuses on developing a biomimetic fish fillet structure using fish muscle cell powder (FMCP) and Alg-κ-Car-based bio-ink, exploring its potential for cultured seafood applications. Grouper muscle satellite cells (GMSCs) were isolated through enzymatic digestion and demonstrated robust growth and myotube differentiation with 2% horse serum (HS). FMCP, derived from the differentiated GMSCs, is characterized as a high-protein source with promising seafood applications. Cytotoxicity analysis reveals FMCP's biocompatibility and its ability to enhance cell proliferation. Alg-κ-Car is chosen as the bio-ink due to its favourable impact on bioink stability. The developed Alg-κ-Car-FMCP bio-ink, with favourable rheological properties, facilitates 3D bioprinting of scaffolds mimicking the texture of native fish fillets. These printed scaffolds retain structural integrity when subjected to boiling and frying. Texture profiles indicate that Alg-κ-Car-FMCP constructs possess enhanced hardness, springiness, gumminess, and chewiness compared to Alg-κ-Car, with cooking influencing textural changes. Taste sensory analysis using an electronic tongue demonstrates Alg-κ-Car-FMCP constructs present a pronounced umami taste, showcasing potential for desirable sensory attributes in cell-based seafood. This study significantly advances cellular aquaculture for cultured seafood production, offering insights for further research and development in sustainable and innovative food production.

Quality tracking of largemouth bass (Micropterus salmoides) fillets during superchilling storage by pretreatment with NaCl

The objective of this research was to investigate the effect of salt pretreatment (1 % and 2 %) on the physicochemical properties, sensory characteristics and safety indices of largemouth fillets during superchilling storage. During superchilling storage, the 2 % group had the lowest values of ice crystal formation temperature, thiobarbituric acid (TBA), total volatile basic nitrogen (TVB-N), and total viable counts (TVC), and the deterioration of fish quality in the 2 % group was significantly slower than that in the 1 % group (P<0.05). At the later stage of storage, low-field nuclear magnetic resonance (LF NMR) results showed that moisture in the fish fillets showed a mixture of ice crystals and water, and TBA, TVB-N, and TVC values were significantly higher in the salt-treated group (P<0.05); the proteins interacted with unfrozen fractions to form relatively ordered structures, which promoted the intensity of protein bands. The pH of the fillets transferred from neutral to weakly acidic throughout the period of storage, and the L*, W and b* values of the 2 % group were significantly lower (P<0.05) than those of the other two groups. The results of shear force, microstructure and western blot (WB) indicated that salt pretreatment significantly improved fillet tenderness and odor. These indicated that the ideal salt pretreatment concentration and quality of the bass fillets for superchilled storage were 2 % and 21 d, respectively. This study provides a theoretical basis for the application of the preservation of aquatic products.

Real-time tracking of fish quality using a cellulose filter paper colorimetric indicator incorporated with prickly pear fruit betacyanins

In the present work, a freshness indicator was developed by immobilizing extracted betacyanins from prickly pear fruit (PFB) onto cellulose filter paper to visually determine fish spoilage. Various properties of the prepared indicator, including color stability, moisture uptake, sensivity to hydrogen sulfide (H2S) gas and pH changes, and chemical analysis were studied. The PFB-based indicator exhibited good color stability at various temperatures and times, with no significan color changes observed during storage at 25, 4, and −18 °C for 8 days. The moisture absorption of the indicator based on PFB was lower than that of cellulose paper, which is crucial for colorimetric indicators. Basic nitrogen and sulfur compounds are the main volatile compounds produced during fish spoilage. The results of the present study showed that both total volatile basic nitrogen (TVB-N) and H2S gas produced during fish spoilage contributed to the color changes of betacyanin-based colorimetric indicators. The prepared freshness indicators were pH-sensitive, with significant color changes due to TVB-N and H2S production during fish storage. A significant correlation was observed between fish quality (pH, TVB-N and total viable count) and the visible color changes of the indicators. The color of the designed indicator shifted from dark pink to pale pink/white during fish storage. These prepared freshness indicators were inexpensive, easy to use, and non-toxic, making them suitable for assessing the quality and shelf life of fish fillets.

Financial Feasibility of Patin Fish Fillet Processing Business in Belitang District, East OKU Regency

Financial Feasibility of Patin Fish Fillet Processing Business in Belitang District, East OKU Regency

Specific spoilage bacteria in cold chain logistics: A study on ATP-related compounds degradation in large yellow croaker (Larimichthys crocea)

This study evaluated the contribution of three spoilage bacteria (Shewanella putrefaciens (S. putrefaciens), Pseudomonas fluorescens (P. fluorescens), and Aeromonas salmonicida (A. salmonicida)) to the degradation of adenosine triphosphate (ATP)-related compounds in fish juice and fillet systems of large yellow croaker during cold chain logistics. The contribution of spoilage bacteria was explored by determining the microbial counts, ATP-related compounds, and associated enzyme activities. The results revealed that the S. putrefaciens, P. fluorescens, and A. salmonicida have the highest activities in 5′-nucleotidase (5′-NT), acid phosphatase (ACP), and alkaline phosphatase (AKP), with 49.78, 162.24, and 142.3 U/gprot, respectively. The rapid degradation of inosine monophosphate (IMP) occurs with increasing 5′-NT activity. It indicates that S. putrefaciens, P. fluorescens, and A. salmonicida mainly secreted 5′-NT, ACP, and AKP to degrade IMP, respectively, and that 5′-NT was the key enzyme in degrading IMP. All three are notable producers of purine nucleoside phosphorylase (PNP) and xanthine oxidase (XOD). The results showed that S. putrefaciens is the primary bacterium in the pre-degradation phase of ATP-related compounds, and A. salmonicida presumably dominates in the post-degradation phase. This study offers critical insights into the research on spoilage mechanisms of marine fish throughout the cold chain logistics.

Effect of konjac glucomannan-based preservation pads on quality changes in refrigerated large yellow croaker (Pseudosciaena crocea)

The purpose of this study was to evaluate the preservation effects of konjac glucomannan (KGM)/oregano essential oil (OEO) Pickering emulsion-based pads (K/OPE pads) on large yellow croaker (Pseudosciaena crocea) fillets stored at 4 °C. The K/OPE pads were fabricated using a freeze-drying technique. The homogeneous distribution of the OEO Pickering emulsions in the KGM matrix was observed using scanning electron microscopy. Fourier transform infrared spectroscopy confirmed that the OEO emulsions were encapsulated in the KGM and there was hydrogen bonding interaction between them. Compared with the KGM pads, the K/OPE pad groups demonstrated enhanced antioxidant and antimicrobial properties. When the content of OPE was increased from 20 % to 40 %, the antioxidant performance of the K/OPE pads increased from 48.09 % ± 0.03 % to 86.65 % ± 0.02 % and the inhibition range of Escherichia coli and Staphylococcus aureus increased to 13.84 ± 0.81 and 16.87 ± 1.53 mm, respectively. At the same time, K/OPE pads were more effective in inhibiting the formation of total volatile alkaline nitrogen and the production of thiobarbituric acid-reactive substances, thereby helping in reducing water loss and maintaining the muscle tissue structure of fish fillets for a longer storage time. Consequently, these K/OPE40 pads extended the shelf life of the fish fillets by an additional 4 days and delayed spoilage during refrigerated storage. The findings suggest that the K/OPE pads can effectively safeguard the quality of refrigerated large yellow croaker fillets, presenting their potential as an active packaging material in the fish preservation industry.

Efficient and sustainable production of intelligent nonwovens as indicators of food spoilage through solution blow spinning of proteins and natural pigments from agri-food waste

The efficient manufacturing of food spoilage indicators based on intelligent nonwovens represents a promising alternative to enable the application of these materials in food quality monitoring. The objective of this study was to rapidly produce intelligent nanofiber nonwovens made of zein/gelatin (Z/G) functionalized with various concentrations (5–15% w/w on the matrix) of anthocyanin-rich food-residue extracts from purple cabbage (CAE) or purple sweet potato (PAE) using the solution-blow-spinning (SBS) technique for use in food-quality-monitoring applications. The addition of CAE or PAE to the Z/G matrix reduced the viscosity of the solution and (consequently) the nanofiber diameters from 999 nm to 882 and 583 nm, respectively. Such incorporation also improved the mechanical, thermal, and water-related properties of the nanofibers and endowed them with antioxidant capacities. Nonwovens composed of Z/G nanofibers with added CAE or PAE, especially at concentrations of 15%, exhibited visible color changes (ΔE ≥ 3) that rapidly altered in response to pH (3–10) and when exposed to ammonia vapor. The nonwovens were successfully used to monitor the deterioration of pasteurized milk and fish fillets. They reveal a visual color change from pink at 0 h to a more intense pink at 48 h in response to milk deterioration and a color change from pink at 0 h to light brown after 48 h when the fish fillets were considered deteriorated. The use of these nanofiber nonwovens to monitor changes in food quality highlights the significant potential of the SBS technique and the use of anthocyanins from agri-food waste to produce new intelligent packaging materials for use in food applications.