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Nanozymes with excellent broad-spectrum antibacterial properties provide a novel strategy to solve the problem of food spoilage caused by microorganisms. Nanozymes can catalyze the corresponding substrates to generate reactive oxygen species (ROS) in a physiological environment. At the same time, because of their simple preparation, low cost, high catalytic efficiency, easy large-scale production and high stability, they have broad applications in the field of food preservation prospect. Therefore, this review comprehensively summarizes the classification of nanozymes, including metal or metal oxide-based nanozymes, carbon-based nanozymes, polymer-based nanozymes, and other materials, and also elaborates on the main factors regulating the antibacterial activity of nanozymes ( size, morphology, coating and modification, composition, etc.), which provides effective guidance for how to design efficient antibacterial nanozymes. Most importantly, the unique application of nanozymes in food preservation, including the application of nanozyme-based antibacterial films and its application in the detection of bacterial contamination levels in food, is described in this paper. Due to its broad-spectrum antibacterial properties and negligible biotoxicity, antibacterial nanozymes can reduce the harm of microorganisms in the food industry, and help to control cross-contamination problems in food production and processing. Sustainable development is of great practical significance. All in all, antibacterial nanozymes are expected to become a novel antibacterial agent and/or strategy, and show broad application prospects in food preservation. [ABSTRACT FROM AUTHOR]

New goals for industry and science have led to increased awareness of food safety and healthier living in the modern era. Here, one of the challenges in food quality assurance is the presence of pathogenic microorganisms. As planktonic cells can form biofilms and go into a sessile state, microorganisms are now more resistant to broad-spectrum antibiotics. Due to their proven antibacterial properties, essential oils represent a potential option to prevent food spoilage in the search for effective natural preservatives. In this study, the chemical profile of Citrus limon essential oil (CLEO) was evaluated. GC-MS analysis revealed that limonene (60.7%), β-pinene (12.6%), and γ-terpinene (10.3%) are common constituents of CLEO, which prompted further research on antibacterial and antibiofilm properties. Minimum inhibitory concentration (MIC) values showed that CLEO generally exhibits acceptable antibacterial properties. In addition, in situ antimicrobial research revealed that vapour-phase CLEO can arrest the growth of Candida and Y. enterocolitica species on specific food models, indicating the potential of CLEO as a preservative. The antibiofilm properties of CLEO were evaluated by MIC assays, crystal violet assays, and MALDI-TOF MS analysis against S. enterica biofilm. The results of the MIC and crystal violet assays showed that CLEO has strong antibiofilm activity. In addition, the data obtained by MALDI-TOF MS investigation showed that CLEO altered the protein profiles of the bacteria studied on glass and stainless-steel surfaces. Our study also found a positive antimicrobial effect of CLEO against S. enterica. The anti-Salmonella activity of CLEO in vacuum-packed sous vide carrot samples was slightly stronger than in controls. These results highlight the advantages of the antibacterial and antibiofilm properties of CLEO, suggesting potential applications in food preservation. [ABSTRACT FROM AUTHOR]

Aims To address the increasingly serious challenge of the transmission of foodbrone pathogens in the food chain. Methods and results In this study, we employed rational design strategies, including truncation, amino acid substitution, and heterozygosity, to generate seven engineered peptides with α-helical structure, cationic property, and amphipathic characteristics based on the original Abhisin template. Among them, as the hybird antimicrobial peptide (AMP), AM exhibits exceptional stability, minimal toxicity, as well as broad-spectrum and potent antimicrobial activity against foodborne pathogens. Besides, it was observed that the electrostatic incorporation demonstrates by AM results in its primary targeting and disruption of the cell wall and membrane of Escherichia coli O157: H7 (EHEC) and methicillin-resistant Staphylococcus aureus (MRSA), resulting in membrane perforation and enhanced permeability. Additionally, AM effectively counteracts the deleterious effects of lipopolysaccharide, eradicating biofilms and ultimately inducing the demise of both food spoilage and pathogenic microorganisms. Conclusions The findings highlight the significant potential of AM as a highly promising candidate for a novel food preservative and its great importance in the design and optimization of AMP-related agents. [ABSTRACT FROM AUTHOR]

Minced meat (MM) has a high surface-to-volume ratio, which makes it prone to the growth of pathogenic and spoilage bacteria due to increased exposure to oxygen and high nutrient levels. In this study, postbiotics were used as a natural preservative to extend the shelf life of MM. Lyophilized postbiotics from Lactobacillus rhamnosus were incorporated into bacterial nanocellulose (BNNC) to create an antimicrobial film for packaging MM. The effectiveness of the postbiotic-embedded BNNC film against Staphylococcus aureus was tested using the disk diffusion method and the optimal postbiotic concentrations were determined using the microdilution broth method. Structural changes of the BNNC film after immersion in postbiotics were examined using scanning electron microscopy, and the attachment and chemical nature of the functional groups in the sample were confirmed using FTIR. The antimicrobial efficacy of the postbiotic-embedded BNNC film against S. aureus in MM was also tested. The results showed that BNNC with 10% (P10-BNNC) and 4% (P4-BNNC) postbiotic concentrations were the optimal films, as confirmed by SEM and FTIR. The P-BNNC films significantly reduced the number of S. aureus during storage of MM for 9 days at 4°C. In conclusion, BNNC can serve as a suitable carrier for creating antimicrobial films using postbiotics derived from LAB for food packaging applications. [ABSTRACT FROM AUTHOR]

Food additives are employed in the food industry to enhance the color, smell, and taste of foods, increase nutritional value, boost processing efficiency, and extend shelf life. Consumers are beginning to prioritize food ingredients that they perceive as supporting a healthy lifestyle, emphasizing ingredients they deem acceptable as alternative or "clean-label" ingredients. Ready-to-eat (RTE) meat products can be contaminated with pathogens and spoilage microorganisms after the cooking step, contributing to food spoilage losses and increasing the risk to consumers for foodborne illnesses. More recently, consumers have advocated for no artificial additives or preservatives, which has led to a search for antimicrobials that meet these demands but do not lessen the safety or quality of RTE meats. Lactates and diacetates are used almost universally to extend the shelf life of RTE meats by reducing spoilage organisms and preventing the outgrowth of the foodborne pathogen Listeria monocytogenes. These antimicrobials applied to RTE meats tend to be broad-spectrum in their activities, thus affecting overall microbial ecology. It is to the food processing industry's advantage to target spoilage organisms and pathogens specifically. [ABSTRACT FROM AUTHOR]

The object of this study was the production of a film based on gelatin and chitosan nanofiber (CNF) and containing β-cyclodextrin/Viola odorata L. (β-CD/viola) inclusion complex to monitor fish freshness and spoilage. As a result, the addition of CNF improved the surface morphology and crystalline structure of the films. The addition of the β-CD/viola complex had no adverse effect on the surface morphology and crystalline structure of the film. In addition, gelatin-based films containing β-CD/viola complex had better water vapor permeability, mechanical properties, and antioxidant activity compared to pure gelatin films. The films incorporated with β-CD/viola complex showed considerable sensitivity against pH changes and ammonia gas, and their color changed from slightly brutal pink to green by increasing pH from 2 to 12. Furthermore, the developed smart colorimetric film is used as an indicator for monitoring Kilka fish spoilage. At the end of the storage time of fish, the color of the indicator film changed from khaki to yellow-green, and its color sensitivity (SRGB) was increased to 9.93%. In conclusion, the gelatin-CNF film containing β-CD/viola complex showed a significant potential for monitoring food spoilage. [ABSTRACT FROM AUTHOR]

objective: Pseudomonas fluorescens is the dominant spoilage organism in frozen foods, and its spoilage-caus¬ing genes are regulated by quorum sensing system. In order to accurately quantify the expression of spoilage genes and thus investigate the mechanism of quorum sensing regulation in food spoilage, it is required to screen reference genes of Pseudomonas fluorescens. Methods: Using Pseudomonas fluorescens PF-08 as the research object, eight common reference genes (dsbA, carA, rpsL, gyrB, atpD, rpoD, gltA, 16S rRNA) were selected and their gene expression was measured by quantitative real-time PCR (qPCR) after incubation with different types of quorum sensing signal molecules. geNorm, Normfinder, BestKeeper and RefFinder were used to evaluate the expression stability of the candidate reference genes and to screen out the most appropriate reference genes. Results: Under different types of exogenous signal molecules incuba¬tion, the least change in Ct value of Pseudomonas fluorescens was gltA and the Ct value of 16S rRNA was too low. The most stable reference genes by geNorm analysis were atpD and rpoD and the combination of the two could more accu¬rately quantify the expression levels of target genes. gltA was the most stable reference gene analyzed by Normfinder and BestKeeper. Further comprehensive evaluation with RefFinder showed rpoD and gltA were the most stable reference genes. Conclusion: Both rpoD and gltA were stably expressed in Pseudomonas fluorescens after incubation with different QS sig¬nal molecules. They could be used for the subsequent study of Pseudomonas fluorescens spoilage gene expression, and could also provide reference genes for studying the expression of QS-related genes in other spoilage bacteria. [ABSTRACT FROM AUTHOR]

Storage pests and the food spoilage they cause are problems of great concern. Using essential oil obtained from different plants as an insecticide against these storage pests can be considered an environmentally friendly pest management option. Lantana camara Linn. (family Verbenaceae) is a flowering species, and is also a noxious weed that can proliferate well in nearly all geographical habitats. A biopesticide derived from the essential oil extracted from this plant can offer an effective solution for controlling storage pests. The goal of this study is to extract and analyse the chemical composition of essential oil obtained from L. camara leaves, and assess its effectiveness as a bioactive substance against three storage pests: Tribolium castaneum, Lasioderma serricorne, and Callosobruchus chinensis. The yield of essential oil extracted from L. camara leaves was about 0.24 ± 0.014%. By employing the GC-MS technique, the major phytochemicals contained in L. camara leaf essential oil were identified as caryophyllene (69.96%), isoledene (12%), and ɑ-copaene (4.11%). The essential oil exhibited excellent fumigant toxicity (LC50 of 16.70 mg/L air for T. castaneum, 4.141 mg/L air for L. serricorne and 6.245 mg/L air for C. chinensis at 24 h), contact toxicity (LC50 of 8.93 mg/cm2 for T. castaneum, 4.82 mg/cm2 for L. serricorne and 6.24 mg/cm2 for C. chinensis after 24 h) along with effective repellent activity towards the test insects. In addition, the oil showed no significant phytotoxicity on the germination of paddy seeds. This presents the potential to utilize a weed in developing a biopesticide for effectively managing stored product insects because of its strong bioactivity. [ABSTRACT FROM AUTHOR]

Drug-resistant bacteria are caused by antibiotic abuse and/or biofilm formation and have become a threat to the food industry. Carbon dot (CD)-based nanomaterials are a very promising tools for combating pathogenic and spoilage bacteria, and they possess exceptional and adjustable photoelectric and chemical properties. In view of the rapid development of CD-based nanomaterials and their increasing popularity in the food industry, a comprehensive and updated review is needed to summarize their antimicrobial mechanisms and applications in foods. This review discusses the synthesis of CDs, antimicrobial mechanisms, and their applications for extending the shelf life of food. It includes the synthesis of CDs using small molecules, polymers, and biomass. It also discusses the different antimicrobial mechanisms of CDs and their use as antibacterial agents and carriers/ligands. CD-based materials have proven effective against pathogenic and spoilage bacteria in food by inhibiting planktonic bacteria and biofilms. Optimization of the production parameters of CDs can help them achieve a full-spectral response, but degradability still requires further research. [ABSTRACT FROM AUTHOR]

Background: Pseudomonas species are common on food, but their contribution to the antimicrobial resistance gene (ARG) burden within food or as a source of clinical infection is unknown. Pseudomonas aeruginosa is an opportunistic pathogen responsible for a wide range of infections and is often hard to treat due to intrinsic and acquired ARGs commonly carried by this species. This study aimed to understand the potential role of Pseudomonas on food as a reservoir of ARGs and to assess the presence of potentially clinically significant Pseudomonas aeruginosa strains on food. To achieve this, we assessed the genetic relatedness (using whole genome sequencing) and virulence of food-derived isolates to those collected from humans. Results: A non-specific culturing approach for Pseudomonas recovered the bacterial genus from 28 of 32 (87.5%) retail food samples, although no P. aeruginosa was identified. The Pseudomonas species recovered were not clinically relevant, contained no ARGs and are likely associated with food spoilage. A specific culture method for P. aeruginosa resulted in the recovery of P. aeruginosa from 14 of 128 (11%) retail food samples; isolates contained between four and seven ARGs each and belonged to 16 sequence types (STs), four of which have been isolated from human infections. Food P. aeruginosa isolates from these STs demonstrated high similarity to human-derived isolates, differing by 41–312 single nucleotide polymorphisms (SNPs). There were diverse P. aeruginosa collected from the same food sample with distinct STs present on some samples and isolates belonging to the same ST differing by 19–67 SNPs. The Galleria mellonella infection model showed that 15 of 16 STs isolated from food displayed virulence between a low-virulence (PAO1) and a high virulence (PA14) control. Conclusion: The most frequent Pseudomonas recovered from food examined in this study carried no ARGs and are more likely to play a role in food spoilage rather than infection. P. aeruginosa isolates likely to be able to cause human infections and with multidrug resistant genotypes are present on a relatively small but still substantial proportions of retail foods examined. Given the frequency of exposure, the potential contribution of food to the burden of P. aeruginosa infections in humans should be evaluated more closely. [ABSTRACT FROM AUTHOR]

In this study, we present an unprecedented reaction of BOPHY. Although tetrabrominated BOPHY (BrBPH) is known to give a substitution reaction with amines, we found that this reaction proceeds through an addition mechanism in the dilute medium. Upon this reaction, the absorption and fluorescence bands of BrBPH decrease dramatically. We used this newly presented reaction for the fluorimetric detection and quantification of amines. BrBPH‐adsorbed TLC plates were also utilized for the determination of food spoilage. [ABSTRACT FROM AUTHOR]

• Combinations demonstrated a novel approach for enhanced antimicrobial activity. • Rosmarinus officinalis with Syzygium aromaticum (methanol extracts) demonstrated synergy (ΣFIC 0.25) against B. cereus. • Salvia officinalis with R. officinalis (methanol extract) was synergistic (ΣFIC 0.31) against B. cereus. • Design of experiments demonstrated a strong correlation (r -value 0.73) between the predicted and experimental MIC values. Herbs and spices are used globally by most population groups across the world. In sub-Saharan Africa, they have medicinal significance in addition to their culinary uses. Although herbs and spices are often used in combination, there are few studies that report on their interactive antimicrobial effect. This study screened 17 culinary herbs and spices (crude extracts and essential oils) for antimicrobial activity, individually, followed by 1:1 combinations of the active extracts, to determine the outcome of combining these for antibacterial activity. The minimum inhibitory concentrations (MIC) were determined against six common foodborne pathogens using the broth microdilution assay. The design of experiments (DOE) approach was subsequently employed in MODDE 9.1® software, to optimise the experimental runs so as to identify the best interaction that would produce the best possible antimicrobial effect. Phytochemical profiling of the most active extracts was achieved using ultra-performance liquid chromatography coupled to mass spectrometry (UPLC-MS) analysis. The results demonstrated that combining Rosmarinus officinalis with either Syzygium aromaticum , or Salvia officinalis methanol extracts produced synergistic antimicrobial effects towards B. cereus with ΣFIC = 0.25 mg/ml and 0.31 mg/ml, respectively. The DOE predicted that a combination of higher ratios of R. officinalis (59.5 %), higher ratios of S. officinalis (40 %), and lower ratios of S. aromaticum (0.5 %) would produce the best antimicrobial effect with MIC = 0.17 mg/ml. This was experimentally confirmed and there was a strong correlation (r-value 0.73) between the predicted and experimental MIC values, leading to the identification of an optimal antimicrobial combination. The combination of R. officinalis (56 %) and S. officinalis (44 %) produced the antimicrobial effect (MIC = 0.19 mg/ml) which can be recommended for future studies. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to study the color change kinetics of lac dye in response to pH and food spoilage metabolites (ammonia, lactic acid and tyramine) for its potential application in intelligent food packaging. Design/methodology/approach: UV-Vis spectroscopy was used to study the color change of dye solution. Ratio of absorbance of dye solution at 528 nm (peak of ionized form) to absorbance at 488 nm (peak of unionized form) was used to study the color change. Color change kinetics was studied in terms of change in absorbance ratio (A528/A488) with time using zero- and first-order reaction kinetics. An indicator was prepared by incorporating lac dye in agarose membrane to validate the result of study for monitoring quality of raw milk. Findings: Dye was orange-red in acidic medium (pH: 2 to 5) and exhibited absorbance peak at 488 nm. It turned purple in alkaline medium (pH: 7 to10) and exhibited absorbance peak at 528 nm. The change in absorbance ratio with pH followed zero-order model. Acid dissociation constant (pKa) of dye was found to be 6.3. Color change of dye in response to ammonia and tyramine followed zero-order reaction kinetics, whereas for lactic acid, the first-order model was found best. In the validation part, the color of the indicator label changed from purple to orange-red when the milk gets spoiled. Originality/value: The study opens a new application area for lac dye. The results suggest that lac dye has potential to be used as an indicator in intelligent food packaging for detection of spoilage in seafood, meat, poultry and milk. [ABSTRACT FROM AUTHOR]

The aim of this work was to investigate the usage possibilities of P. terebinthus fruit, which has a limited usage area, in the food industry. Antimicrobial activity of hexane extract obtained from P. terebinthus fruits from Adıyaman (Turkey) was determined by disc diffusion and micro-dilution assays against test microorganisms. In addition, the antibacterial activity of the extract on Escherichia coli O157:H7, one of the most important food-borne pathogens, was determined by viable cell count using a macro-dilution assay. The potential for use of the extract with probiotic candidate lactic acid bacteria (LAB) strains was also investigated. The hexane extract presented antimicrobial activity against all the tested microorganisms, with good inhibition zone diameters between 10.51 mm and 18.02 mm. MIC and MFC or MBC values of P. terebinthus fruit extract were determined as 5-80 µg/µL against all tested microorganisms. The lowest MIC and MBC values (5 µg/µL) of the extract were obtained against E. coli O157:H7. Macro-dilution assay results indicated that the P. terebinthus extract at various concentrations (5-10-20 mg/mL) inhibited the growth of E. coli O157:H7 more than the control group after all of the incubation hours. No viable E. coli O157:H7 cells were detected after 48 hours at all concentrations. The extract showed low antimicrobial activity, and relatively high bactericidal concentration on probiotic candidate LAB strains. This shows that P. terebinthus hexane extract at appropriate concentrations can be used together with probiotic strains as a natural preservative and biopreservative to prevent food spoilage and extend shelf life. [ABSTRACT FROM AUTHOR]

Most Pseudomonas spp. are responsible for spoilage in refrigerated foods such as alteration in flavor, texture and appearance. Samples of Minas Frescal cheese with blue discoloration were analysed and contained a high Pseudomonas concentration (7.72 ± 0.36 log CFU/g). Out of the 26 Pseudomonas isolates that were analyzed in our study, 19 demonstrated the capability of producing a diffusible dark pigment. Thus, a pigment-producing isolate (C020) was selected by rep-PCR fingerprinting and subsequently subjected to whole-genome sequencing. The draft genome assembled comprises 42 contigs totaling 6,366,75 bp with an average G + C content of 59.97%, and the species prediction performed by TYGS server, based on the draft genome sequence, identified the C020 as Pseudomonas carnis. In order to investigate the phylogenetic relationships of this isolate with strains already identified of this species, we performed an analysis based on whole-genomic sequences. First, an analysis of all P. carnis genomes deposited in GenBank to date shows that 11% (4/37) are misidentified, and belong to the Pseudomonas paracarnis species. A comparative analysis based on phylogenomic analysis has showed that there is no evolutionary relationship between P. carnis strains carrying second copies of trp genes related to blue discoloration (trpABCDF). This finding reinforces the assertion that these genes are contained in a mobile genetic element. However, it is worth noting that all strains carrying these secondary gene copies have exclusively been isolated from food sources. This observation provides valuable insights into the potential origins and dispersion dynamics of this genetic trait within the species. [ABSTRACT FROM AUTHOR]

Food borne pathogens (bacteria, viruses, parasites, fungi or their mycotoxins) are the major cause of substantial number of diseases with an important impact on human well-being and economy. Contamination or spoilage of food by pathogens is linked with a diverse range of outbreaks of food-borne diseases. World Health Organization defined food-borne disease as an infectious disease which is caused by contaminated food or water. However, antibiotics are vital tools used in the healthcare sector to antagonize food-borne pathogens. The frequent usage of antibiotics has resulted in antimicrobial resistance which is causing major threats throughout the world. Over the past years, there has been an increasing interest in the use of probiotic bacteria as alternatives to antibiotics. Generally, the use of probiotics improves gastrointestinal well-being has been suggested for several years however many critical issues arise in the use of probiotics. Therefore, the notion of paraprobiotics and postbiotics are comparatively novel concepts which do not fit in terms of probiotics. Paraprobiotics and postbiotics are produced from probiotic organisms which provide beneficial impacts on food commodities and human health. This review will provide insight into probiotics, paraprobiotics and postbiotics against food-borne pathogens; and their probiotic challenges. [ABSTRACT FROM AUTHOR]

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Foodborne diseases are one of the main issues for human health, and antibacterial packaging plays a major role in food security assurance. Silver ultra nanoparticles (Argirium SUNc) are antimicrobial agents that have a wide spectrum of action, including against pathogenic bacteria and spoilage fungi. The aim of the present study was to evaluate the antibacterial activity of Argirium SUNc on the bacteria most commonly found in food: Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Listeria monocytogenes, and Salmonella typhimurium. In this regard, an in vitro study was carried out by assessing the Argirium SUNc effectiveness on different concentrations of each tested microbial strain and at different time intervals. The data showed that the antimicrobial activity of Argirium SUNc was directly related to the microbial concentration and varied depending on the microbial species. Moreover, a greater effectiveness against Gram-negative bacteria than Gram-positive bacteria was observed. These preliminary results provided important information on the silver nanoparticles spectrum of action, and this is an aspect that appears particularly promising for obtaining a viable alternative to traditional antimicrobials to be used against the pathogens and spoilage agents most commonly found in the food chain, harmful both to health and quality aspects. [ABSTRACT FROM AUTHOR]

Food spoilage due to browning is one of the major challenges faced by the food and processing industries. In fruits and vegetables, browning due to both enzymatic and nonenzymatic reactions is a common event that renders them unattractive and unsuitable for consumption. In the last few decades, numerous studies have been conducted to slow or inhibit these undesirable physiological reactions during processing and storage. An experiment was carried out to determine the effect of different antibrowning agents on the quality and shelf life of fresh-cut pineapple from 2020-2021 in the laboratory of the Department of Horticulture at Annamalai University. The experiment consisted of 11 treatments and was replicated 3 times, viz., T1 (ascorbic acid 500 ppm), T2 (ascorbic acid 1000 ppm), T3 (citric acid 250 ppm), T4 (citric acid 500 ppm), T5 (sodium chloride 100 ppm), T6 (sodium chloride 200 ppm), T7 (calcium chloride 100 ppm), T8 (calcium chloride 200 ppm), T9 (honey 5%), T10 (honey 10%), and T11 (control). Antibrowning agents significantly and positively impacted the quality parameters of fresh-cut fruits. The minimum PLW (0.71%) and maximum scores of firmness (2.16kg/cm²), titratable acidity (0.53%), total sugar (11.65%), nonreducing sugar (1.94%) and texture index (2.37) were recorded in T8. However, maximum TSS (14.6 °Brix), total sugar (11.65%), and reducing sugar (9.48%) were recorded in T10. The lowest browning rate was recorded in the treatment with ascorbic acid in T2. The treatments with calcium chloride and ascorbic acid best retained the quality of fresh-cut pineapple fruit. [ABSTRACT FROM AUTHOR]

Actively combating post-harvest food spoilage and waste can dramatically increase the efficiency of food utilization worldwide. In climacteric fruits, chemical treatments such as 1−MCP are an effective way of reducing post-harvest spoilage and waste by inhibiting the fruit's ability to perceive ethylene. 1−MCP treatment is increasingly being used to explore the complex nature of ripening physiology at a fundamental level; however, differences in application and quantitation methods create difficulties in comparing conclusions across studies. Here, we report an effective and reproducible method for 1−MCP application and quantitation for small–medium-sized research applications. By use of surrogate alkene standards 1-butene and cis-2-butene, the highly volatile and elusive 1−MCP molecule can be identified and quantified by gas chromatography and subsequent standard curves may be developed. It is hoped that the methodology outlined here can help standardize consistent 1−MCP application for post-harvest research without excessive investment in specialized equipment. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the response efficiency of colorimetric indicator films based on carboxymethyl cellulose (CMC) incorporated with different anthocyanins [Karanda alone (CMC/AK), butterfly pea alone (CMC/AB), and a mixture of anthocyanins from Karanda and butterfly pea (CMC/AK75/AB25)] for tracking shrimp freshness during storage at different temperatures and times (4 °C for 8 days and 25 °C for 30 h). The mathematical models were also applied to predict their freshness and shelf life. The CMC/AK75/AB25 indicator film was the most sensitive and clearly changed color, which could be distinguished by the naked eye. Color changes indicated the shrimp deterioration processes: dark purple (fresh), purplish gray or gray (semi-fresh), and olive green or brown (spoilage). During shrimp storage at temperatures of 4 and 25 °C, the pH reached 7.52 and 8.14, TVB-N 35.98 and 72.72 mg/100 g, and TVC 5.75 and 7.88 log CFU/g, respectively, indicating shrimp had completely deteriorated. Furthermore, there was a positive correlation between the ΔE value of the indicator film and both TVB-N and TVC. These findings suggest that the CMC/AK75/AB25 indicator film could serve as a real-time visual indicator for tracking shrimp freshness and could enhance the guarantee of shrimp safety.

Developing countries such as Ecuador carry a heavy food safety burden but reports on the microbiological quality of their foods are scarce. In this investigation, the microbial diversity of 10 high-risk and mass-consumption street-vended foods including bolones, encebollado, food dressings, ceviche, chopped fruits, fruit juices, fruit salads, cheese, raw chicken, and ground beef in Quito, Guayaquil, and Cuenca, three major population centers in Ecuador, were evaluated using 16S rRNA gene High Throughput Sequencing. In total, 1,840 amplicon sequence variants (ASVs) were classified into 23 phyla, 253 families, 645 genera, and 829 species. In the tested food samples, Proteobacteria and Firmicutes were the most abundant phyla accounting for 97.41% of relative abundance (RA). At genus level, 10 dominant genera were identified: Acinetobacter (12.61% RA), Lactococcus (12.08% RA), Vibrio (8.23% RA), Weissella (7.43% RA), Aeromonas (6.18% RA), Photobacterium (6.32% RA), Pseudomonas (3.92% RA), Leuconostoc (3.51% RA), Klebsiella (3.49% RA), and Cupriavidus (2.86% RA). The highest microbial diversity indices were found in raw chicken, encebollados, fruit salads, and fruit juices from Guayaquil and Cuenca. From sampled foods, 29 species were classified as food spoilage bacteria and 24 as opportunistic pathogenic bacteria. Two groups associated with human diseases were identified, including 11 enteric species and 26 species of fecal bacteria. The occurrence of recognized and opportunistic pathogenic bacteria, as well as enteric and fecal microorganisms, in the street-vended foods indicated extensive risks for the consumers’ health. This study demonstrated the application of culture-independent amplicon sequencing in providing a more comprehensive view of microbial safety for street-vended food, which could be a useful tool to facilitate the control of foodborne diseases.

Currently, active and intelligent packaging has been developed to solve the spoilage problem for protein-rich foods during storage, especially by adding anthocyanin extracts. In such a film system, the antioxidant and antibacterial properties were dramatically increased by adding anthocyanins. The physicochemical properties were enhanced through interactions between the active groups in the anthocyanins and reactive groups in the polymer chains. Additionally, the active and intelligent film could monitor the spoilage of protein-rich foods in response to pH changes. Therefore, this film could monitor the sensory acceptance and extend the shelf life of protein-rich foods simultaneously. In this paper, the structural and functional properties of anthocyanins, composite actions of anthocyanin extracts and biomass materials, and reinforced properties of the active and intelligent film were discussed. Additionally, the applications of this film in quality maintenance, shelf-life extension, and quality monitoring for fresh meat, aquatic products, and milk were summarized. This film, which achieves high stability and the continuous release of anthocyanins on demand, may become an underlying trend in packaging applications for protein-rich foods. [ABSTRACT FROM AUTHOR]

Microbial shelf life refers to the duration of time during which a food product remains safe for consumption in terms of its microbiological quality. Predictive microbiology is a field of science that focuses on using mathematical models and computational techniques to predict the growth, survival, and behaviour of microorganisms in food and other environments. This approach allows researchers, food producers, and regulatory bodies to assess the potential risks associated with microbial contamination and spoilage, enabling informed decisions to be made regarding food safety, quality, and shelf life. Two-step and one-step modelling approaches are modelling techniques with primary and secondary models being used, while the machine learning approach does not require using primary and secondary models for describing the quantitative behaviour of microorganisms, leading to the spoilage of food products. This comprehensive review delves into the various modelling techniques that have found applications in predictive food microbiology for estimating the shelf life of food products. By examining the strengths, limitations, and implications of the different approaches, this review provides an invaluable resource for researchers and practitioners seeking to enhance the accuracy and reliability of microbial shelf life predictions. Ultimately, a deeper understanding of these techniques promises to advance the domain of predictive food microbiology, fostering improved food safety practices, reduced waste, and heightened consumer confidence. [ABSTRACT FROM AUTHOR]

Ensuring the quality of meat is crucial to preventing health hazards caused by improper handling. To address this issue, a smart packaging system is necessary for continuous monitoring of beef quality and microbial population, benefiting both meat industries and end consumers. The presence of spoilage-causing microbes can be detected using an electronic nose (e-nose), a cost-effective and rapid instrument for beef quality classification. This research introduces the development of a mobile e-nose system for beef quality detection and monitoring. The system comprises a chemical gas sensor array, a data acquisition system, a data processing system, and a pattern recognition system. The gas sensors utilized in the sensor array include MQ135, MQ137, MQ9, MQ3, TGS 2620, TGS 2610, TGS 2600, and TGS 822. The experiment involved a dataset with 1800 data points. The experimental results demonstrate the system's ability to accurately distinguish between fresh and spoiled beef. Furthermore, it exhibits a promising classification accuracy of 95.89% using the Support Vector Machine model. Therefore, this system presents a potential solution for a low-cost, user-friendly, and real-time meat quality monitoring system. This research contributes to the development of an accessible and efficient meat quality monitoring system, addressing the need for continuous assessment and ensuring consumer safety. [ABSTRACT FROM AUTHOR]

Summary: Smart packaging is an emergent solution commonly used to indicate the current quality and freshness of the food. In this study, a pH indicator film without an anthocyanin‐extraction step was developed, based on purple‐fleshed sweet potato powder (SPP) prepared by freeze drying process, with starch or starch and carboxymethyl cellulose (CMC). The colour of the powder and the films changed from pink to green with the pH change from 1 to 11. The effectiveness of the indicator films was assessed by the ground beef spoilage trial, which resulted in a colour change from purple to green when the pH of the meat raised from 5.54 to 7.92. The microbiological growth and the sensory changes of the meat confirmed the deterioration process. Therefore, developed indicator films could successfully indicate the spoilage of packaged ground beef. [ABSTRACT FROM AUTHOR]

This study optimized the expression of the enterocin P peptide (EntP) in CHO cells using medium additions. Furthermore, the minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and anti-biofilm effects of Ent-P were examined against several gram positive and gram-negative microorganisms. The findings indicated that increasing medium with 0.75 percent glycerol and 0.75 percent DMSO boosted Ent-P peptide synthesis by around two times. According to Ent-P antimicrobial evaluations, Shigella disentri (4 g/mL) and Escherichia coli (128 g/mL) had the lowest and highest MIC values, respectively. In comparison to Enterococcus faecalis and Escherichia coli (3+ to 2+), the Ent-P peptide shown a strong ability to suppress the formation of the biofilm generated by Staphylococcus aureus and Pseudomonas aeruginosa (4 + to +1). [ABSTRACT FROM AUTHOR]

In this study, pathogenic and food spoilage bacteria Chryseobacteria spp. were isolated by a new method from 150 samples of raw milk (26/50), heat-treated milk (HTM) (5/50) and butter (2/50). The species with the highest prevalence was C. indologenes (10.67%) followed by C. bovis and C. gleum (4.67% each), and C. bernardetii (2%). The three new strains C. bernardetii, C. gleum, and C. indologenes were named MW703610, MW703611, and MW703612, respectively, with identities ranging from 97.8% to 98.9%. Gene sequencing was performed on some isolates and proved the highest sequence similarity for C. bernardetii WD1 (97.8%), C. gleum WD2 (98.9%) and C. indologenes WD3 (98.9%). Most of the isolated Chryseobacteria spp. showed proteolytic and lipolytic activity. Therefore, casein and alpha-lactalbumin were used as natural antibacterial substances against all isolates. Higher bioactivity against the isolates was obtained using casein rather than the alphalactalbumin. Based on these results, casein and alpha-lactalbumin may be promising natural bioactive agents against pathogenic Chryseobacteria spp. Further studies should be done to establish the natural peptide fractions associated with the observed activity. [ABSTRACT FROM AUTHOR]

Carbon dioxide is highly produced by microbial spoilage of food. Thus, the freshness of the marketed products can be represented by sensors visually highlighting the existence of CO2 within the food packages as labels. In the present work, FTIR and SEM, and XRD were used to synthesize and characterize l-lysine imprinted polymers. Then, it was utilized as a biosensor for CO2 sensing under phenyl red. By investigating its performance under CO2 gas, its applicability was proved via this synthesized biosensor for spoilage monitoring of packaged minced beef. The aerobic psychrotrophic count (PTC), aerobic plate count (APC), and Enterobacteriaceae counts were monitored to assess the samples' microbial quality in this period. The results revealed that the synthesized biosensor can act as a prevailing senor to monitor meat quality and imprint lysine on this polymer thus improving and catalyzing its reversible performance. [ABSTRACT FROM AUTHOR]

The costs of food deterioration in terms of both money and health are rising. Fungi, bacteria, yeast, insects, and rodent contamination of food supplies continue to be a major public health concern. Chemical preservatives are effective but can be potentially fatal to human health in certain cases. As potent food preservatives, essential oils made from plants are a great alternative to synthetic preservatives. They also possess a variety of antiinflammatory, antibacterial, and antioxidant effects. The use of artificial sweeteners in food products, which raises safety questions and health issues while also having reduced nutritional value, is another problem in the food industry. Because natural sweeteners are linked to a healthy lifestyle and have superior nutritional qualities, consumers today prefer them. This article goes through the issues with artificial sweeteners and preservatives and goes into great length about the many different essential oils and natural sweeteners that are much safer and healthier alternatives. [ABSTRACT FROM AUTHOR]

South Africa has been challenged with loadshedding for the past decade. Most recently, loadshedding became a crisis as the year 2022 was reportedly the most in which electricity was load shed compared to the previous years. Guided by the South African Constitution of 1996, the right of South Africans to access electricity is embedded within the constitutional obligations of Eskom. The power utility is mandated to provide reliable electricity supply and ensure just administrative action when taking actions that deprive citizens of electricity access (Pieterse, 2023). In practice, however, it has become evident that rendering services such as electricity remains a major challenge. South Africans experience loadshedding daily, which affects their energy usage. In essence, loadshedding has impacted negatively, especially the disadvantaged. Despite planned loadshedding stages, households still experience direct impacts of loadshedding. Appliances such as refrigerators become mal-functional, resulting in food kept in cool temperatures being spoiled. Although loadshedding food spoils have been identified as a phenomenon at household level, the current response in terms of household planning and awareness has not been adequately documented. The paper aims to address this by arguing that there is a need for households to engage in targeted measures that help households cope and adapt to loadshedding food spoils. Furthermore, the study provides a TO-DO list on how households can improve their ability to adapt and cope with loadshedding. The paper used a qualitative methodology focused on analysing the lived experiences of News24 participants. Literature review was conducted where journal articles, newspapers and books were analysed. Thereafter, lessons are drawn from literature, to develop and provide a way forward towards dealing with loadshedding food spoilage at household level. The findings of the paper conclude that effective loadshedding and food spoil adaptation can limit food spoilage. [ABSTRACT FROM AUTHOR]

Many people around the world are concerned about meat safety and quality, which has resulted in the ongoing advancement of packaged food technology. Since the emergence of graphene in 2004, the number of studies on layered two-dimensional materials (2DMs) for applications ranging from food packaging to meat quality monitoring has been expanding quickly. Recently, scientists have been working hard to develop a novel class of 2DMs that keep the good things about graphene but don't have zero bandgaps at room temperature. Much work has been done on layered transition metal dichalcogenides (TMDCs) like different metal sulfides and selenides for meat spoilage gas sensors. This review looks at (i) the main indicators of meat spoilage and (ii) the detection methods that can be used to find out if meat has been spoiled, such as chemiresistive, electrochemical, and optical methods. (iii) the role of 2DMs in meat spoilage detection and (iv) the emergence of advanced methods for selective classification of target analytes in meat/food spoilage detection in recent years. Thus, this review demonstrates the potential scope of 2DMs for developing intelligent sensor systems for food and meat spoilage detection with high viability, simplicity, cost-effectiveness, and other multipurpose tools. [ABSTRACT FROM AUTHOR]

The antibacterial activities of quercetin and hyperoside were evaluated towards two major spoilage bacteria in fish, Pseudomonas aeruginosa (PA) and Shewanella putrefaciens (SP). Hyperoside showed a lower minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) towards both spoilage bacteria, PA and SP, than quercetin. Cell membrane morphology was affected when treated with hyperoside and quercetin. The release of content from the treated cells occurred, as ascertained by the release of potassium and magnesium ions and the increase in conductivity of the culture media. The morphology of cells was significantly changed, in which shrinkage and pores were obtained, when observed using SEM. Both compounds negatively affected the motility, both swimming and swarming, and the formation of extracellular polymeric substance (EPS), thus confirming antibiofilm activities. Agarose gel analysis revealed that both compounds could bind to or degrade the genomic DNA of both bacteria, thereby causing bacterial death. Molecular docking indicated that the compounds interacted with the minor groove of the DNA, favoring the adenine–thymine-rich regions. Thus, both quercetin and hyperoside could serve as potential antimicrobial agents to retard the spoilage of fish or perishable products. [ABSTRACT FROM AUTHOR]

Alternaria species are cosmopolitan fungi darkly pigmented by melanin that infect numerous plant species causing economically important agricultural spoilage of various food crops. Alternaria spp. also infect animals, being described as entomopathogenic fungi but also infecting warm-blooded animals, including humans. Their clinical importance in human health, as infection agents, lay in the growing number of immunocompromised patients. Moreover, Alternaria spp. are considered some of the most abundant and potent sources of airborne sensitizer allergens causing allergic respiratory diseases, as severe asthma. Among the numerous strategies deployed by Alternaria spp. to attack their hosts, the production of toxins, carrying critical concerns to public health as food contaminant, and the production of hydrolytic enzymes such as proteases, can be highlighted. Alternaria proteases also trigger allergic symptoms in individuals with fungal sensitization, acting as allergens and facilitating antigen access to the host subepithelium. Here, we review the current knowledge about the mechanisms of Alternaria pathogenesis in plants and animals, the strategies used by Alternaria to cope with the host defenses, and the involvement Alternaria allergens and mechanisms of sensitization. [ABSTRACT FROM AUTHOR]

Contaminated fungi on dried salted fish of three species including Talang queenfish (TQF, Scomberroides commersonianus), Hamilton's thryssa fish (HTF, Thryssa hamiltonii), and Cobia fish (CF, Rachycentron canadum) were isolated and identified. One hundred and sixty‐nine isolates were obtained from TQF and HTF, respectively, while no fungi were detected in CF. The dominant genera were Aspergillus spp. (n = 79), Penicillium spp. (n = 60), and non‐sporulating fungi (n = 30). The representative groups of Aspergillus spp. (n = 6) and Penicillium spp. (n = 3) based on different morphological characteristics were selected for species identification by molecular methods involving ITS1‐5.8s‐ITS2 region and Matrix‐Assisted Laser Desorption/Ionization Time‐of Flight Mass Spectrometer (MALDI‐TOF MS) analysis. The nine isolates were identified to be Aspergillus versicolor (n = 2), Aspergillus montevidensis (n = 3), Penicillium citrinum (n = 3), and Aspergillus sp. (n = 1). The antifungal activity of chitooligosaccharide‐gallic acid (COS‐GAL) conjugate against A. versicolor F1/10M9, A. montevidensis F1/30M20, and P. citrinum F1/23M14 was examined. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) values were in the range of 0.625–2.5 mg/mL and 1.25–10 mg/mL, respectively. COS‐GAL conjugate at the concentration of 5 mg/mL completely inhibited the spore germination of A. versicolor F1/10M9 and P. citrinum F1/23M14 after 72 h of treatment. COS‐GAL conjugate at 4 × MIC mainly affected the mycelium of A. versicolor F1/10M9 and P. citrinum F1/23M14 after treatment with COS‐GAL conjugate for 3 days by coating mycelium surface and reducing the size of mycelium. Therefore, COS‐GAL conjugate could be used as a food additive to inhibit or prevent the growth of fungi contaminated in dried salted fish or other relevant products. Practical Application: During processing, dried salted fish can be contaminated with fungi, which may cause food poisoning and food spoilage. The contaminated fungi are capable of producing mycotoxin that is harmful to consumers. Synthetic food preservatives have long been used to inhibit fungal growth, but the side effects to consumers are of concern. Chitooligosaccharide is a nontoxic chitosan derivative produced from shrimp shell and its conjugate namely chitooligosaccharide‐gallic acid conjugate showed high efficacy in inhibiting the growth of fungi including Aspergillus spp. and Penicillium spp. Therefore, it can serve as a natural alternative preservative for the prevention of fungal growth in dried salted fish. [ABSTRACT FROM AUTHOR]

Food spoilage is one of the key concerns in the food industry. One approach is the improvement of the shelf life of the food by introducing active packaging, and another is intelligent packaging. Detecting packed food spoilage in real-time is key to stopping outbreaks caused by food-borne diseases. Using active materials in packaging can improve shelf life, while the nonharmful color indicator can be useful to trace the quality of the food through simple color detection. Recently, bio-derived active and intelligent packaging has gained a lot of interest from researchers and consumers. For this, the biopolymers and the bioactive natural ingredient are used as indicators to fabricate active packaging material and color-changing sensors that can improve the shelf life and detect the freshness of food in real-time, respectively. Among natural bioactive components, carotenoids are known for their good antimicrobial, antioxidant, and pH-responsive color-indicating properties. Carotenoids are rich in fruits and vegetables and fat-soluble pigments. Including carotenoids in the packaging system improves the film's physical and functional performance. The recent progress on carotenoid pigment-based packaging (active and intelligent) is discussed in this review. The sources and biological activity of the carotenoids are briefly discussed, and then the fabrication and application of carotenoid-activated packaging film are reviewed. The carotenoids-based packaging film can enhance packaged food's shelf life and indicate the freshness of meat and vegetables in real-time. Therefore, incorporating carotenoid-based pigment into the polymer matrix could be promising for developing novel packaging materials. [ABSTRACT FROM AUTHOR]

Background: The use of omics data for monitoring the microbial flow of fresh meat products along a production line and the development of spoilage prediction tools from these data is a promising but challenging task. In this context, we produced a large multivariate dataset (over 600 samples) obtained on the production lines of two similar types of fresh meat products (poultry and raw pork sausages). We describe a full analysis of this dataset in order to decipher how the spoilage microbial ecology of these two similar products may be shaped differently depending on production parameter characteristics. Methods: Our strategy involved a holistic approach to integrate unsupervised and supervised statistical methods on multivariate data (OTU-based microbial diversity; metabolomic data of volatile organic compounds; sensory measurements; growth parameters), and a specific selection of potential uncontrolled (initial microbiota composition) or controlled (packaging type; lactate concentration) drivers. Results: Our results demonstrate that the initial microbiota, which is shown to be very different between poultry and pork sausages, has a major impact on the spoilage scenarios and on the effect that a downstream parameter such as packaging type has on the overall evolution of the microbial community. Depending on the process, we also show that specific actions on the pork meat (such as deboning and defatting) elicit specific food spoilers such as Dellaglioa algida, which becomes dominant during storage. Finally, ecological network reconstruction allowed us to map six different metabolic pathways involved in the production of volatile organic compounds involved in spoilage. We were able connect them to the different bacterial actors and to the influence of packaging type in an overall view. For instance, our results demonstrate a new role of Vibrionaceae in isopropanol production, and of Latilactobacillus fuchuensis and Lactococcus piscium in methanethiol/disylphide production. We also highlight a possible commensal behavior between Leuconostoc carnosum and Latilactobacillus curvatus around 2,3-butanediol metabolism. Conclusion: We conclude that our holistic approach combined with largescale multi-omic data was a powerful strategy to prioritize the role of production parameters, already known in the literature, that shape the evolution and/or the implementation of different meat spoilage scenarios. [ABSTRACT FROM AUTHOR]

Artificial olfactory systems (AOSs) that mimic biological olfactory systems are of great interest. However, most existing AOSs suffer from high energy consumption levels and latency issues due to data conversion and transmission. In this work, an energy‐ and area‐efficient AOS based on near‐sensor computing is proposed. The AOS efficiently integrates an array of sensing units (merged field effect transistor (FET)‐type gas sensors and amplifier circuits) and an AND‐type nonvolatile memory (NVM) array. The signals of the sensing units are directly connected to the NVM array and are computed in memory, and the meaningful linear combinations of signals are output as bit line currents. The AOS is designed to detect food spoilage by employing thin zinc oxide films as gas‐sensing materials, and it exhibits low detection limits for H2S and NH3 gases (0.01 ppm), which are high‐protein food spoilage markers. As a proof of concept, monitoring the entire spoilage process of chicken tenderloin is demonstrated. The system can continuously track freshness scores and food conditions throughout the spoilage process. The proposed AOS platform is applicable to various applications due to its ability to change the sensing temperature and programmable NVM cells. [ABSTRACT FROM AUTHOR]

Drying is one of the oldest and most widely used methods for food preservation. It reduces the availability of moisture and inhibits microbial and enzymatic spoilage in food products. Foam mat drying is a mild drying technique used for semiliquid and liquid foodstuff. It is useful for heat-sensitive and sticky liquid food products. In this process, liquid food is converted into foam using surfactant additives, which can be a foaming agent or foam stabilizer. These additives are surface-active compounds of vegetative and animal origins. The foamed material is then convectively dried using hot air. The foam mat drying is an efficient and economical technique. With the emergence of different hybrid techniques such as foam mat freeze drying, foamed spray drying, foamed vacuum drying, and microwave assisted foam mat drying, the powders' physical, chemical, and functional properties have enhanced many folds. These strategies have shown very promising results in terms of cost and time efficiency in almost all the cases barring a few exceptions. This review article attempts to comprehensively summarize the mechanisms dictating the foam mat drying process, novel technological tools for modeling, mathematical and computational modeling, effects of various foaming additives, and various hybrid techniques employed to foam mat drying. [ABSTRACT FROM AUTHOR]

Food additives are substances of natural origin or obtained by chemical synthesis. Among these additives, food antioxidants play an essential role in preserving food quality by neutralizing free radicals and inhibiting oxidation reactions, which helps prevent food spoilage and maintain its freshness, taste, and nutritional value. In addition, dietary antioxidants may also be beneficial to health. This is particularly the perception that consumers have in relation to antioxidants of natural origin, such as plant extracts. In this paper, we focused on the case of rosemary extract as a food additive which is authorized in many countries, including the United States and Europe, under the code E392. Through the examination of patent documents available in specialized databases and using appropriate keywords, our research made it possible to go back in time to first show the uses of rosemary extract and then specify the exploitation of rosemary extract in the field of food. We selected 411 relevant documents (granted patents and patent applications), almost 40% of which were filed in China. The first patent found was published in 1984, and it concerned a method to obtain a highly effective antioxidant from rosemary suitable for preventing the oxidation of food. This patent was followed by others which claimed, among others, more effective methods of making rosemary extract. More recently, innovations have focused on the synergistic effect of rosemary extract with other compounds, particularly for the antimicrobial action of food preservation. [ABSTRACT FROM AUTHOR]

A sensitive, portable, easy-to-operate, directly-readable food freshness monitoring device has been developed for rapid visual identification of mild food spoilage. [ABSTRACT FROM AUTHOR]

The unambiguous detection and classification of volatile organic compounds (VOCs) are crucial in many fields. For using VOC‐sensing to explore the alteration and spoilage of food, very inexpensive sensors are desired. Simple colorimetric sensors seem highly attractive for these applications. Here, a label‐free, colorimetric sensor array made of metal‐organic‐framework‐based (MOF‐based) Fabry‐Pérot (FP) films is presented where the signal read‐out is performed either by their optical spectra or by pictures taken with a smartphone camera. Exposing the FP‐MOF‐films to various VOCs causes a reversible shift of the photonic pattern, where the magnitude of the shift depends on the VOC type, its concentration, and the MOF structure. The application of machine‐ learning‐ algorithms on the sensor data allows to identify the VOCs with a high classification accuracy (92% at 100 ppm). It is shown that the sensor array read‐out can also be performed with a common smartphone camera, also precisely classifying the VOC analytes. Moreover, fresh and spoiled food, like milk and meat, is distinguished by its head space. Thus, the study presents a very inexpensive platform of small colorimetric sensors that allow determining the quality, alteration, and spoilage of food, and it may contribute to realizing smart labels and intelligent packaging. [ABSTRACT FROM AUTHOR]

The real-time monitoring of food freshness in refrigerators is of significant importance in detecting potential food spoiling and preventing serious health issues. One method that is commonly reported and has received substantial attention is the discrimination of food freshness via the tracking of volatile molecules. Nevertheless, the ambient environment of low temperature (normally below 4 °C) and high humidity (90% R.H.), as well as poor selectivity in sensing gas species remain the challenge. In this research, an integrated smart gas-tracking device is designed and fabricated. By applying pump voltage on the yttria-stabilized zirconia (YSZ) membrane, the oxygen concentration in the testing chamber can be manually tailored. Due to the working principle of the sensor following the mixed potential behavior, distinct differences in sensitivity and selectivity are observed for the sensor that operated at different oxygen concentrations. Typically, the sensor gives satisfactory selectivity to H2S, NH3, and C2H5OH at the oxygen concentrations of 10%, 30%, and 40%, respectively. In addition, an acceptable response/recovery rate (within 24 s) is also confirmed. Finally, a refrigerator prototype that includes the smart gas sensor is built, and satisfactory performance in discriminating food freshness status of fresh or semi-fresh is verified for the proposed refrigerator prototype. In conclusion, these aforementioned promising results suggest that the proposed integrated smart gas sensor could be a potential candidate for alarming food spoilage. [ABSTRACT FROM AUTHOR]

Today, many different methods are applied for the correct use of foods and to prevent their deterioration. Ensuring healthy conditions for people in food consumption and consumption of healthy foods is very important for human welfare. In this study, food spoilage, the factors that cause food spoilage, its effects on a global basis, food transport systems (cold chain) and measures that prevent or delay food spoilage are discussed. [ABSTRACT FROM AUTHOR]

Summary: Fermented foods such as yogurt, kefir and sauerkraut have been part of the human diet throughout history and have gained attention in recent years due to their immense health and nutritional benefits. As a result, fermented foods are considered biofuel for the human microbiome which helps to boost the immune system. Fermented foods are those foods and beverages that are produced by employing specific microbial‐based fermentation aids such as yeasts and bacteria, particularly lactic acid bacteria (LAB). Through controlled enzymatic reactions, these microbial cultures transform food components as substrates into value‐added products promoting various healthy fermentative activities. These microbes in fermented foods also produce compounds that can inhibit food spoilage and pathogenic microorganisms, thereby extending the product shelf of fermented products. Probiotics are live microbiota with beneficial health properties, prevent gastrointestinal diseases and modulate the human microbiome. Thus, foods that are fermented by certain strains of probiotic bacteria that exhibit evidence of health benefits are referred to as probiotic fermented foods. This review describes fermented and functional foods, probiotics and their relationship to human health. In addition, we offer our perspective on the distinct differences between probiotic and fermented foods to promote awareness for consumers and key stakeholders regarding these highly functional and nutritionally fermented food products. [ABSTRACT FROM AUTHOR]

[Display omitted] • Porous hydrogels were designed as smart tags to improve sensitivity. • The soluble starch with gellan gum leads to phase separation for a porous structure. • The porous smart tags have high sensitivity, modulus, and safety. • The porous smart tags can be utilized to indicate milk and shrimp spoilage. Hypothesis: The pH-indicating smart packaging and tags are identified within the general research and pH colorimetric smart tags are effective, non-invasive methods for indicating food freshness on a real-time basis, but their sensitivity is limited. Experiments: In Herin, we developed a porous hydrogel with high sensitivity, water content, modulus, and safety. Hydrogels were prepared with gellan gum, starch, and anthocyanin. The phase separations provide an adjustable porous structure, which can enhance the capture and transformation of gas from food spoilage, hence improving the sensitivity. Hydrogel is physically crosslinked by the entanglement of chains through freeze-thawing cycles, and porosity can be adjusted by the addition of starch, so avoiding the use of toxicity crosslinkers and porogen. Findings: Our study demonstrates that the gel undergoes an obvious color shift during the spoilage of milk and shrimp, revealing its potential application as a smart tag signaling food freshness. [ABSTRACT FROM AUTHOR]