Search Results (128)

Exopolysaccharides (EPSs) produced by lactic acid bacteria (LAB) have received special attention as valuable products due to their potential applications as techno-functional and bioactive ingredients in foods. EPS production and consumption are an age-old practice in humans, as evidenced by fermented foods. Over the last two decades, extensive research has examined, analyzed, and reported a wide variety of EPSs from several LAB strains, as well as their techno-functional properties in foods. Also, research efforts focused on EPS characterization and yield production have been carried out. In food applications, EPS quantification and characterization in situ (direct fermentation) took place in various matrices (dairy, bread, plant-based fermented, and meat products). EPS direct application (ex situ) has been less investigated despite its better structural–functional control and use in non-fermented foods. Fewer EPS investigations have been conducted related to health benefits in humans and their mechanisms of action. The composition and functionality of EPSs vary depending on the LAB strain and food matrix used to produce them; thus, various challenges should be addressed before industrial applications are performed. This review aims to compile and summarize the recent findings on EPSs produced by LAB, highlighting their yield, culture production, techno-functional role in foods, food applications, and health benefits in clinical trials. It examines their dual applications, whether as purified functional ingredients (ex situ) or as fermentation products (in situ), and critically assesses both technological and bioactive implications. Also, it explores production challenges, regulatory considerations, and future perspectives for sustainable and tailored applications of EPSs in food innovation. Full article

Biogenic amines (BAs) are nitrogenous compounds naturally present in protein-rich foods, whose accumulation may indicate spoilage and pose health risks. This study presents the development and validation of a rapid LC–MS/MS method for the simultaneous quantification of six BAs—putrescine (PUT), cadaverine (CAD), histamine (HIS), tyramine (TYR), spermidine (SPD), and spermine (SPM)—in meat products, without requiring derivatisation. Sample preparation was optimized to enhance extraction efficiency and reproducibility, using 0.5 M HCl and a double-centrifugation protocol to avoid matrix interference. Chromatographic separation was optimized using a C18 column and acidified ammonium formate/acetonitrile mobile phases. The method showed good linearity (R² > 0.99), trueness between −20% and +20%, and acceptable precision (RSD_r and RSD_R ≤ 25%). Limits of quantification were established at 10 µg/g for all analytes. The method was applied to ten commercial meat samples, where PUT, TYR, and SPD were the most frequently detected amines. Although HIS and TYR levels were below toxicological thresholds for healthy individuals, one sample showed TYR levels potentially concerning for monoamine oxidase inhibitors -treated consumers. The Biogenic Amine Index (BAI) further supported product quality assessment, identifying early spoilage in selected cases. This method offers a rapid, robust and efficient tool for routine monitoring of BAs in meat products, supporting food safety and quality control initiatives. Full article

Listeria monocytogenes is a foodborne pathogen capable of contaminating ready-to-eat meat products, e.g., frankfurters. Post-packaging mild heat treatment via water immersion is commonly employed; however, this may be sublethal to cells located in protected niches or beneath the product surface. The objectives of this study were to evaluate thermal injury of L. monocytogenes on frankfurters at single-cell versus population level and to comparatively estimate pathogens’ physiological status. Pork frankfurter-type sausages were inoculated (ca. 7.0–7.5 log CFU/cm²) with L. monocytogenes strain EGDE-e. Heat treatment was performed at 61 °C (max. 60 min) and 64 °C (max. 12 min). To determine the injured subpopulation from the total, tryptic soy agar with 0.6% yeast extract (TSAYE), supplemented or not with 5% NaCl, was used. Plating-based quantification of injured cells was compared to CFDA/PIstained cells analysed by fluorescence microscopy and quantified with Fiji software. Injury was recorded mainly after 2 and 4 min at 64 °C, whereas no injury was detected at 61 °C, at population level. Following exposure to 61 °C for 60 min, culturable cells dropped below the enumeration limit (0.3 log CFU/cm²), while a considerable number of CFDA⁺/PI⁻ and CFDA⁺/PI⁺ cells indicated viable-but-non-culturable induction and sublethal injury, respectively. These findings suggest that non-culturability may limit the accuracy of solely culture-based enumeration methods. Full article

Accurate and non-invasive assessment of fat and muscle composition is crucial for biomedical monitoring to track health conditions in humans and pets, as well as for classifying meats in the meat industry. This study introduces a cost-effective, multifunctional ultra-wideband microwave system operating from 2.4 to 4.4 GHz, designed for rapid and non-destructive quantification of fat thickness, muscle thickness, and fat-to-muscle ratio in diverse ex vivo samples, including pork, beef, and oil–water mixtures. The compact handheld device integrates essential RF components such as a frequency synthesizer, directional coupler, logarithmic power detector, and a dual-polarized Vivaldi antenna. Bluetooth telemetry enables seamless real-time data transmission to mobile- or PC-based platforms, with each measurement completed in a few seconds. To enhance signal quality, a two-stage denoising pipeline combining low-pass filtering and Savitzky–Golay smoothing was applied, effectively suppressing noise while preserving key spectral features. Using a random forest regression model trained on resonance frequency and signal-loss features, the system demonstrates high predictive performance even under limited sample conditions. Correlation coefficients for fat thickness, muscle thickness, and fat-to-muscle ratio consistently exceeded 0.90 across all sample types, while mean absolute errors remained below 3.5 mm. The highest prediction accuracy was achieved in homogeneous oil–water samples, whereas biologically complex tissues like pork and beef introduced greater variability, particularly in muscle-related measurements. The proposed microwave system is highlighted as a highly portable and time-efficient solution, with measurements completed within seconds. Its low cost, ability to analyze multiple tissue types using a single device, and non-invasive nature without the need for sample pre-treatment or anesthesia make it well suited for applications in agri-food quality control, point-of-care diagnostics, and broader biomedical fields. Full article

Amidst growing demand for meat products, concerns regarding their authenticity and safety have intensified, primarily due to potential fraudulent substitutions of cheaper meats, which are not accurately labeled. This study presents a novel strategy for the rapid screening and validation of target peptides for accurate quantitative analysis using high-resolution mass spectrometry (HRMS) coupled with multivariate statistical analysis. By integrating hierarchical clustering analysis (HCA) with parallel reaction monitoring (PRM), five species-specific peptides were validated as reliable biomarkers for pork quantification. These peptides demonstrated accurate quantification in simulated meat products with known accurate contents, achieving recoveries of 78–128%, with RSD less than 12%. This methodology markedly enhances screening efficiency by excluding 80% of non-quantitative peptides, providing a robust solution for meat authenticity verification. Full article

Natural casings are integral components in the production of various meat products, including sausages, and their quality and safety have to be controlled to eliminate any risks to consumers’ health. A total of 35 samples of salted natural sheep casings from Turkey, Iran, China, Mongolia, Pakistan, New Zealand, the United Kingdom, and Belgium were tested for microbial contamination and the concentrations of potentially toxic heavy metals. The mean log values of microbial counts were determined at 3.45 ± 0.44 log CFU/g for aerobic mesophilic bacteria, 0.5 ± 0.43 log CFU/g for anaerobic sulfide-reducing bacteria, and 1.24 ± 0.63 log CFU/g for coagulase-positive staphylococci. Typical or suspected colonies of Salmonella spp., E. coli, and Listeria spp. were not identified on selective and differential agar. The examined casings were contaminated mainly with lead (0.077 ± 0.045 mg/kg), followed by arsenic (0.036 ± 0.029 mg/kg) and cadmium (0.009 ± 0.008 mg/kg). The concentrations of mercury in all samples were below the limit of quantification. The study demonstrated that the quality and safety of natural casings were not affected by their region of origin and that microbial contamination was not correlated with heavy metal concentrations. Full article

In the efforts towards germplasm innovation of livestock and poultry, strategies to improve meat quality have faced some increasingly challenging and dynamic concerns. Intramuscular fat (IMF) content and backfat thickness are two important traits contributing to meat quality. MicroRNAs (miRNAs)—a class of endogenous noncoding RNAs maintaining cell homeostasis by inhibiting target gene expression—have been proven as critical regulators of body fat deposition, thus affecting farm animal production. Our previous in vitro and in vivo models of pigs have clarified that miR-130b overexpression can obviously suppress adipogenesis of subcutaneous preadipocytes and lower backfat thickness. However, the way miR-130b regulates proliferation and adipogenesis of primary cultured porcine intramuscular preadipocytes (PIMPA) and the underlying mechanism are still unknown. PIMPA derived from longissimus dorsi muscle were employed to examine the role of miR-130b in proliferation and adipogenesis and to further elucidate its underlying mechanism. Lipid deposition in cytoplasm was evaluated by TG quantification and ORO-staining, and EDU-staining was employed to measure cell proliferation. Adipogenic and proliferation-related gene expression were conducted by qPCR and Western blot. MiR-130b overexpression markedly stimulated proliferation of PIMPA by increasing cell cycle-related gene expression. Furthermore, overexpression of miR-130b significantly inhibited adipogenic differentiation of PIMPA, mainly by inhibiting expression of adipogenic differentiation marker genes PPAR-γ and SREBP1. In addition, we proved that miR-130b significantly inhibited expression of PPAR-γ downstream target genes and ultimately repressed adipogenesis. Ssc-miR-130b accelerated proliferation but inhibited adipogenic differentiation of PIMPA, contributing to an enhanced knowledge of the function of ssc-miR-130b in lipid deposition, and providing potential implications for enhancing pork quality. Full article

Paleontologists and archeologists reconstruct ancient ecosystems using data from carnivores’ food remains. Carnivores have evolved to employ two primary feeding strategies: consuming mostly meat and focusing on both meat and bones, and these strategies result in the production of different feces. Hyenas are exemplary meat-eaters and bone-crushers. While fecal characteristics like shape, color, size, and inclusions are often used for species identification, the detailed composition of hyena feces remains largely unexplored. To address this, we conducted a multimodal analysis of feces-like coprolites from four modern Hyaenid species, using scanning electron microscopy (SEM) and Fourier transform infrared spectrometry (FTIR). This approach allowed for the detection and quantification of the proportions of calcium phosphate/carbonate, silts, organic matter, and crystallinity in the coprolites. Our preliminary findings suggest that multivariate statistical analysis of these components could provide a reliable method for species identification based solely on fecal content, results which can be applied in research on fossil materials. Full article

Heterocyclic aromatic amines (HAAs), known for their mutagenic and carcinogenic potential, are formed during the heating of protein-rich food items. Detecting HAAs swiftly and accurately poses challenges due to complex food matrices and low HAA concentrations. In this study, a simple and efficient magnetic solid-phase extraction (MSPE) strategy was developed for the simultaneous isolation and enrichment of three HAAs such as 2-amino-3,4,8-trimethylimidazo [4,5-f]quinoxaline (4,8-DiMeIQx), 2-amino-3,8-dimethylimidazo [4,5-f]quinoxaline (MeIQx), and 2-amino-3-methylimidazo [4,5-f]quinoline (IQ) in processed meats, employing the magnetic covalent organic framework Fe₃O₄@MOF-545-AMSA as an adsorbent. It was synthesized via a solvothermal method, with Fe₃O₄ as the magnetic core. Its building blocks are as follows: zirconium (Zr) as the coordination metal ion, tetrakis(4-carboxyphenyl)porphyrin and benzoic acid as organic ligands, and aminomethanesulfonic acid (AMSA). This composite captures targeted HAAs efficiently by exploiting the unique porous MOF-545-AMSA structure, specific metal–ligand coordination, and AMSA’s amino and sulfonic acid groups. The quantification of HAAs was achieved through the combination of Ultra-Performance Liquid Chromatography–Tandem Mass Spectrometry (UPLC-MS/MS) and MSPE, demonstrating satisfactory linearity (R² ≥ 0.9917), high recovery rates (83.7–111.0%), and low detection limits (0.1–1.0 μg/kg). Moreover, an automated high-throughput detection system was developed using MSPE to assess the presence of HAAs in meat products. Full article

Toxic metals and metalloids food contamination is a source of health risks; this study evaluated lead (Pb), cadmium (Cd), and arsenic (AS) contamination in the meat, liver, kidneys, heart, and lungs of guinea pigs raised on a farm near a mini mineral concentrator and with pastures irrigated with wastewater in the Central Andes of Peru. The risk of consuming these elements was estimated in the Peruvian population aged 2 to 85 years, whose consumption is 660 g/per capita/year. The quantification of Pb, Cd, and As was carried out via Inductively Coupled Plasma Atomic Emission Spectrometry. The heart had 3.3, 4.3, 7.3, and 81 times more Pb than the liver, lung, kidneys, and meat. The liver had 1.02, 2.22, 9.15, and 722.5 times more Cd than the kidneys, heart, lungs, and meat, respectively. The kidneys had 1.16 and 1.72 times more As than the liver and heart, respectively. The Target Hazard Quotient (TQH) and Hazard Index (HI) for Pb, Cd, and As, were <1 in the entire population, and there was no risk from their consumption. The cancer risk values found in the study are within the tolerated ranges. The findings expand the scientific basis for the safe and innocuous production of guinea pigs in the Central Andes of Peru and provide evidence to establish limits on water, soil, pastures, and agri-food products. Full article

Red meat consumption is considered a risk factor for colorectal cancer (CRC) development and stimulated isolation of plasmid-like DNA molecules from bovine serum and milk, termed bovine meat and milk factors (BMMFs). BMMFs encode a conserved replication protein (Rep). Increased populations of Rep-expressing macrophages have been identified in the peritumor of CRC patients and pre-cancerous tissues when compared to the tissues of healthy individuals. This supports the concept that BMMFs increase cancer risk by indirect carcinogenesis, upon induction of chronic inflammation. However, the spread of Rep⁺ immune cells in tissues at greater distances from primary tumors has not yet been assessed. Here, we immunohistologically analyzed the presence of Rep⁺ immune cells in sets of tumor, peritumor and, additionally, distant tissues of CRC patients (n = 13). We identified consistently high numbers of BMMF-positive macrophages in mucosal tissues at distances of as much as 25 cm away from the primary tumors, at levels comparable to peritumors and associated with M2-like macrophage polarization. The broad distribution of BMMFs suggests that BMMF⁺ macrophages might already exist at stages of pre-cancerous dysplasia or before. Quantification of BMMF tissue expression during colonoscopy might help to preventively stratify individuals at risk of developing polyps/CRC and recommend them for enhanced surveillance and/or changes in dietary lifestyle. Full article

Volatile chemicals containing nitrogen and sulfur as key odors in dry-cured meat products have extremely low odor thresholds. These compounds play an important part in the overall uniqueness and characteristic flavor of dry-cured meat products, contributing to savory and toasted aroma sensations, respectively. In this review, we define the different volatiles and aroma compounds related to the flavor of dry-cured meat products. Moreover, the main differences regarding volatiles, aromas, and flavor profiles from non-fermented and fermented dry-cured meat products are summarized. Comparisons using the same volatile extraction techniques revealed that dry loins contained the most sulfur- and nitrogen-containing compounds, while complex flavor and aroma compounds in fermented sausages were greatly impacted by the fermentation process. The screening and quantification of savory and toasted odors showed that methionol, dimethyl sulfide, and 2-methyl-3-(methylthio)furan were mainly reported in non-fermented products, whereas pyrazines were mainly detected in fermented meat products. Finally, the different mechanisms in the generation of savory and toasted aromas, including chemical reactions and biochemical reactions by microorganisms (bacteria, yeast, and molds), are discussed. These discussions will help to better understand the complex flavor of dry-cured meat products. Full article

Amid the global rise in type 2 diabetes, natural peptide-based therapies provide a safer alternative to synthetic drugs with fewer side effects. This study highlights the antidiabetic potential of peptides derived from cultured Chinese giant salamander (CGS) meat hydrolyzed by Alcalase 2.4L FG through DPP4 inhibitory activity. The hydrolysate exhibited significant DPP4 inhibitory activity, with an IC₅₀ value of 1317.0 ± 29.5 μg/mL. Using activity-guided modified-SPE fractionation, the most potent DPP4 inhibitory peptide, PPAAQLL (PL7), was identified from CGS alcalase hydrolysate, with an IC₅₀ of 230.1 ± 4.9 μM. PL7 was identified as a non-competitive inhibitor through enzyme kinetic studies, and intermolecular docking simulations suggested that it does not interact with the active site of DPP4. Additionally, PL7’s stability against DPP4 and simulated gastrointestinal protease digestion suggested that its inhibitory activity remains intact, indicating potential for effective oral administration. SRM quantification analysis revealed nearly a six-fold enrichment of PL7 in the RP-SPE fraction S1 compared to the crude hydrolysate, underscoring the effectiveness of the fractionation method. These findings highlight CGS alcalase hydrolysate as a promising source of DPP4 inhibitory peptides for managing type 2 diabetes. Future studies should focus on the in vivo efficacy, bioavailability, and pharmacokinetics of PL7. Full article

Bisphenol A (BPA) is a typical environmental estrogen that is distributed worldwide and has the potential to pose a hazard to the ecological environment and human health. The development of an efficient and sensitive sensing strategy for the monitoring of BPA residues is of paramount importance. A novel electrochemical sensor based on carbon black and carbon nanofibers composite (CB/f-CNF)-assisted signal amplification has been successfully constructed for the amperometric detection of BPA in foods. Herein, the hybrid CB/f-CNF was prepared using a simple one-step ultrasonication method, and exhibited good electron transfer capability and excellent catalytic properties, which can be attributed to the large surface area of carbon black and the strong enhancement of the conductivity and porosity of carbon nanofibers, which promote a faster electron transfer process on the electrode surface. Under the optimized conditions, the proposed CB/f-CNF/GCE sensor exhibited a wide linear response range (0.4–50.0 × 10⁻⁶ mol/L) with a low limit of detection of 5.9 × 10⁻⁸ mol/L for BPA quantification. Recovery tests were conducted on canned peaches and boxed milk, yielding satisfactory recoveries of 86.0–102.6%. Furthermore, the developed method was employed for the rapid and sensitive detection of BPA in canned meat and packaged milk, demonstrating comparable accuracy to the HPLC method. This work presents an efficient signal amplification strategy through the utilization of carbon/carbon nanocomposite sensitization technology. Full article

Ajwain essential oil and thyme essential oil naturally contain important bioactive compounds. Various researchers have discovered that these compounds contribute biological benefits for living things such as humans and animals. Bioactive compounds found in essential oils, such as terpenes and terpenoids, possess antibacterial and flavouring qualities, making them promising natural preservatives in the food business. This study investigates the effect of essential oil treatment methods on their incorporation into dehydrated beef and its subsequent sensory acceptability. The meat samples underwent hot air blanching and oil treatment with doses of 0.75 mL and 1.5 mL, respectively. Subsequently, the samples were dried at 55 °C for 6 h after each treatment. The identification and quantification of volatile chemicals were performed using headspace solid-phase microextraction and gas chromatography–mass spectrometry. Thymol, γ-terpinene, p-cymene, and β-pinene were the predominant compounds before and after the treatments. The findings revealed that the application of ajwain and thyme essential oil treatments resulted in significant differences in the final concentration of monoterpenes. However, the sensory evaluation indicated that the ajwain and thyme essential oil samples received similar overall ratings. Consequently, ajwain essential oil could be a suitable alternative to thyme in beef jerky. Full article