Search Results (77)

Yeast biosensors represent a promising biotechnological innovation for ensuring the safety and quality of fermented beverages such as beer, wine, and kombucha. These biosensors employ genetically engineered yeast strains to detect specific contaminants, spoilage organisms, or hazardous compounds during fermentation or the final product. By integrating synthetic biology tools, researchers have developed yeast strains that can sense and respond to the presence of heavy metals (e.g., lead or arsenic), mycotoxins, ethanol levels, or unwanted microbial metabolites. When a target compound is detected, the biosensor yeast activates a reporter system, such as fluorescence, color change, or electrical signal, providing a rapid, visible, and cost-effective means of monitoring safety parameters. These biosensors offer several advantages: they can operate in real time, are relatively low-cost compared to conventional chemical analysis methods, and can be integrated directly into the fermentation system. Furthermore, as Saccharomyces cerevisiae is generally recognized as safe (GRAS), its use as a sensing platform aligns well with existing practices in beverage production. Yeast biosensors are being investigated for the early detection of contamination by spoilage microbes, such as Brettanomyces and lactic acid bacteria. These contaminants can alter the flavor profile and shorten the product’s shelf life. By providing timely feedback, these biosensor systems allow producers to intervene early, thereby reducing waste and enhancing consumer safety. In this work, we review the development and application of yeast-based biosensors as potential safeguards in fermented beverage production, with the overarching goal of contributing to the manufacture of safer and higher-quality products. Nevertheless, despite their substantial conceptual promise and encouraging experimental results, yeast biosensors remain confined mainly to laboratory-scale studies. A clear gap persists between their demonstrated potential and widespread industrial implementation, underscoring the need for further research focused on robustness, scalability, and regulatory integration. Full article

Syringic acid (SA) is a natural derivative of syringaldehyde (SD), derived from lignin depolymerization. Its application in the food industry focuses on the properties of natural functional ingredients; it is mainly used as a food antioxidant and food preservative, but can also be used as an ingredient to enhance food flavor and functional foods. This compound exhibits a remarkable spectrum of biological activities, including potent antioxidant, anti-inflammatory, neuroprotective, hypoglycemic, detoxifying, and anti-cancer effects, positioning it as a highly promising candidate for pharmaceutical and nutraceutical applications. In this study, suitable sites were first screened through homologous sequence alignment, and a variant of aryl-alcohol oxidase (CgAAO) with high efficiency in catalyzing the conversion of SD to SA was obtained via site-directed mutagenesis. A deep eutectic solvent (DES) system based on choline chloride/urea (ChCl/UR) in water was developed to enhance SA production. Additionally, key parameters of the biological reaction were optimized, including temperature, pH, metal ions, as well as the type and dosage of DES. The optimal performance was achieved using recombinant E. coli pRSFDuet-CgAAO-Y335F whole-cell biocatalysts, yielding 75% and producing 0.75 g/L SA in 100 mM KPB buffer (pH 7.0) containing 5 wt% ChCl/UR and 1 mM Fe³⁺. This study established a novel biosynthetic pathway for SA that was efficient, mild, green, and environmentally friendly. Full article

Oxidative stability plays an important role in determining the quality of oxidation-sensitive foods and beverages such as beer, wine, and edible oils. Oxidation occurs through radical chain reactions producing off-flavors and leading to deterioration and decrease in the quality and nutritional value of food and beverages. In this context, electron paramagnetic resonance (EPR) spectroscopy has emerged as a powerful and selective technique for investigating reactions involving paramagnetic species, particularly free radicals and transition metal ions. This review provides a critical overview of the applications of EPR spectroscopy in the study of the oxidative stability and antioxidant activity of the above-mentioned matrices. It highlights the main methodological approaches that this technique can offer to gain insight into oxidative processes. Furthermore, current advances in low-cost and portable EPR instrumentation are discussed, along with their implications for broader adoption in both research and industry settings. The aim is to provide an up-to-date literature survey on the application of EPR spectroscopy for studying the oxidative stability and antioxidant activity of beer, wine, and edible oils, providing a methodological tool for academic and food industry researchers interested in monitoring, improving, and extending food shelf life through reliable analytical tools. Full article

This study investigated the effects of dietary supplementation with an alkaline metal ion complex (AMIC) on growth performance, meat quality, rumen microbiota, and metabolome in Hu lambs. Fifty lambs were randomly assigned to either a control group (basal diet) or an AMIC group (basal diet + 0.15% AMIC) for 60 days. The results showed that AMIC significantly increased carcass weight, Longissimus dorsi area, crude protein, intramuscular fat, ash content, and meat luminosity (L*). Amino acid profiles and key flavor compounds were elevated, while off-flavor hydrocarbons were reduced. 16S rRNA sequencing revealed that AMIC altered rumen microbiota composition, enriching butyrate-producing genera such as Butyrivibrio and Saccharofermentans. Metabolomic analysis identified 398 differentially expressed metabolites, with upregulated pathways including butanoate metabolism and xylene degradation. Correlation analyses indicated strong associations between specific microbial taxa, metabolites, and meat quality traits. These findings suggest that AMIC enhances meat quality by modulating rumen microbial ecology and metabolic pathways, leading to improved nutrient deposition and flavor development. This study provides novel insights into the microbe–metabolite–muscle axis in ruminants and supports the use of AMIC as a dietary strategy for quality lamb production. Full article

Cadmium (Cd), a toxic and mobile heavy metal, poses significant risks to agricultural systems due to industrial pollution. Tea plants (Camellia sinensis L.) efficiently absorb and accumulate Cd from soil, leading to contamination in leaves. Chronic consumption of Cd-laden tea can cause severe health issues, including neurological, reproductive, and immunological disorders, as well as increased cancer risk. Despite growing concerns, the molecular mechanisms of Cd stress response in tea plants remain poorly understood. Current research highlights key physiological adaptations, including activation of antioxidant defenses and modulation of secondary metabolite pathways, which influence tea quality. Cd disrupts photosynthesis, induces oxidative stress, and alters the biosynthesis of flavor-related compounds. Several critical genes involved in Cd transport (e.g., CsNRAMP5, CsHMA3, CsZIP1), sequestration (CsPCS1), and stress regulation (CsMYB73, CsWRKY53, CsbHLH001) have been identified, offering insights into molecular responses. This review systematically examines Cd dynamics in the soil-tea plant system, its effects on growth, photosynthesis, and quality, and the physiological and biochemical mechanisms underlying Cd tolerance. By consolidating recent findings on Cd-responsive genes and regulatory pathways, this study provides a theoretical foundation for breeding Cd-resistant tea varieties and ensuring production safety. Furthermore, it identifies future research directions, emphasizing the need for deeper mechanistic insights and practical mitigation strategies. These advancements will contribute to safer tea consumption and sustainable cultivation practices in Cd-contaminated regions. Full article

pH-responsive technology enables precise control over the release of functional molecules, thereby maximizing their bioavailability. As the first comprehensive assessment of pH-responsive systems within food science, this review systematically examines the mechanism of pH-triggered release, which covers the protonation and deprotonation of functional groups and the breaking of dynamic covalent bonds (such as imines, disulfides, and metal coordination bonds). The design strategies, responsiveness, and application potential of key carrier materials are evaluated. In addition, the applications of pH-responsive release technologies in nutrient delivery, flavor encapsulation, and food preservation are highlighted, demonstrating enhanced bioavailability, extended shelf life, and improved sensory quality. Despite promising advancements achieved so far, significant challenges remain in ensuring material stability, and meeting safety and regulatory requirements. Future research directions are proposed, including the development of food-grade, eco-friendly, and stable carrier materials, the leveraging of AI-driven optimization for integrated systems, integrating multi-stimuli responsiveness, and establishing robust safety profiles to facilitate regulatory approval, collectively establishing a solid foundation for next-generation sustainable and intelligent food packaging and delivery systems. Full article

Agaricus subrufescens Peck is a nutrient-rich edible fungi with a distinctive flavor, but most varieties are sensitive to cadmium (Cd), making cadmium contamination common during cultivation. Currently, excessive fertilizer uses and increased solid waste are exacerbating cadmium contamination in soils. Since A. subrufescens utilize agricultural residues like straw and livestock manure as cultivation substrates, Cd can be adsorbed readily, leading to secondary accumulation. In this study, the toxic effects of and response mechanisms to different Cd concentrations with respect to mycelial growth, heavy metal accumulation, and antioxidant systems of A. subrufescens were systematically investigated. The results indicated that the mycelia exhibited Cd accumulation capacity, with accumulation levels positively correlated with stress concentration. At a Cd concentration of 5 mg/L, the intracellular Cd concentration in the mycelia reached approximately 800 mg/kg. As the Cd concentration increased, the efficiency of Cd uptake by mycelia correspondingly decreased. Cadmium stress (≥0.5 mg/L) significantly inhibited mycelial growth and induced morphological abnormalities, with the mycelia exhibiting yellowing. Furthermore, Cd induced dose-dependent oxidative stress. Hydrogen peroxide and MDA levels peaked at a Cd concentration of 2 mg/L, reaching 2.26 μmol/g and 8.98 nmol/g, respectively, indicating heightened lipid peroxidation. Low concentrations of Cd (≤2 mg/L) promoted increases in ASA and GSH activity. SOD, POD, GR, and APX activities significantly increased, with the ASA-GSH cycle synergistically scavenging ROS. CAT activity remained persistently inhibited, APX/GR activity was suppressed, and total sugar metabolism was disrupted, leading to the collapse of antioxidant defenses. In summary, depending on the Cd concentration, A. subrufescens mycelia exhibit markedly different responses at low versus high concentrations. This study provides a foundation for further research into the application of edible fungi in heavy metal-resistant cultivation. Full article

The consumption of edible flowers has gained increasing global attention, driven by the demand for natural and functional foods. Edible flowers are consumed in various forms, including fresh, dried, or as ingredients in derived products such as infusions, dietary supplements, and honey. Their growing popularity is associated not only with their ability to enhance sensory properties, such as aroma, color, and flavor, but also with their potential health-promoting effects. Nevertheless, their consumption entails safety concerns related to possible contamination with pesticide residues, heavy metals, insects, microorganisms, and naturally occurring toxic compounds. Among these, tropane alkaloids (TAs) and pyrrolizidine alkaloids (PAs) represent major toxicological concerns. These alkaloids may be detected even in non-producing species due to cross-contamination in the field, horizontal transfer through soil, or pollination by bees that have previously visited TA- or PA-producing plants. This review addresses the risks associated with the consumption of edible flowers and flower-derived products, with particular emphasis on studies published since 2018. It provides an overview of the occurrence of TAs and PAs in fresh flowers, floral infusions, dietary supplements, and honey. Furthermore, it summarizes the analytical methodologies employed, including sample preparation and detection techniques, and compiles the reported concentrations of these alkaloids. The evidence presented highlights the need for continued investigation to establish reliable risk assessments and ensure consumer safety. Full article

This study investigated the effect of storage time on the quality of low-sugar apple jams partially substituted with steviol glycosides (SGs). Apple jams were prepared with 0%, 10%, 20%, 30%, and 40% sugar replacement using highly purified SGs (95.1%). The jams were evaluated immediately after production and after 3 and 6 months of storage at 22 °C in the dark. Physicochemical analyses included dry matter, total soluble solids, vitamin C, total ash, pH, titratable acidity, malic acid, and color parameters (L*, a*, b*). Sensory and microbiological assessments were also carried out. During storage, the dry matter content significantly decreased from 41.4% (control) to 35.6% (40% SGs), while titratable acidity increased from 10.69° to 16.73° (p < 0.05), and pH values remained stable (3.15–3.29). Vitamin C content decreased significantly (from 0.56 mg/100 g to 0.19 mg/100 g; 33–66% degradation). The color of jams became lighter with increasing SG substitution (L* increased from 17.19 to 24.73; ΔE up to 9.66) and slightly darkened after storage (ΔL ≈ −1.0). Microbiological analysis confirmed complete safety, with total colony counts < 10 CFU/g and no presence of Listeria monocytogenes or coagulase-positive Staphylococcus. Sensory evaluation by a trained panel (10 assessors, aged 34–56 years, with similar training in fruit and vegetable preserve evaluation) showed that jams with 10–30% SG substitution maintained desirable apple aroma and sweetness, whereas higher SG levels enhanced metallic odor (0.12–0.95 c.u.) and bitterness (0.2–1.9 c.u.) while slightly reducing apple flavor intensity (p < 0.05). Despite these differences, all jams remained acceptable after 6 months of storage. Overall, replacing up to 40% of sucrose with steviol glycosides provided microbiological stability, controlled color changes, and acceptable sensory quality, supporting the production of low-sugar jams in line with clean-label and sustainability trends in modern food technology. Full article

Background/Objectives: Over the past twenty years, there has been a rapid increase in studies aimed at comprehending how cells communicate with each other via Extracellular Vesicles (EVs), accompanied by a heightened interest in plant-derived extracellular vesicles due to their potential relevance in dietary supplementation and therapeutic applications. However, there is a limited amount of research on extracellular vesicles derived from mushrooms (MDEVs). Among edible mushrooms, Pleurotus eryngii is peculiar due to its flavor and interesting nutritional profiling. It also produces a wide array of secondary metabolites including biologically active compounds with many health-promoting benefits such as anticancer, antioxidant, antitumor, antiviral, antibacterial, antidiabetic, and anti-hypercholesteremic activities. The aim of this work has been to isolate EVs from the fruiting body and mycelium of P. eryngii in order to investigate their potential applications as nutraceuticals. Methods: MDEVs were isolated by differential and density gradient centrifugation, characterized by Nanoparticle Tracking Analysis (NTA), Scanning Electron Microscopy (SEM) and immunoblotting, and subjected to metabolomic and phenolic profiling. Their antioxidant potential was assessed through in vitro radical scavenging (DPPH, ABTS) and metal-reducing (CUPRAC, FRAP) assays. Results: The findings suggest that mycelium-derived EVs may represent a valuable source of high-quality MDEVs, which exhibited promising antioxidant properties in all assays conducted, particularly in radical scavenging assays. Conclusions: These results highlight the potential of P. eryngii mycelium-derived EVs as a novel natural source of bioactive compounds, paving the way for future applications in nutraceutical and therapeutic fields. Full article

The aromatic C₁₃ apocarotenoid β-ionone is a high-value natural-flavor and -fragrance compound derived from the oxidative cleavage of carotenoids. Carotenoid cleavage dioxygenases (CCDs) play a pivotal role in the biosynthesis of volatile apocarotenoids, particularly β-ionone. In this study, we report the identification, cloning, and functional characterization of two CCD1 homologs: OeCCD1 from Olea europaea and InCCD1 from Ipomoea nil. These two species, which, respectively, represent a woody perennial and a herbaceous annual, were selected to explore the potential functional divergence of CCD1 enzymes across different plant growth forms. These CCD1 genes were synthesized using codon optimization for Escherichia coli expression, followed by heterologous expression and purification using a GST-fusion system. In vitro assays confirmed that both enzymes cleave β-carotene at the 9,10 (9′,10′) double bond to yield β-ionone, but only OeCCD1 exhibits detectable activity on zeaxanthin; InCCD1 shows no in vitro cleavage of zeaxanthin. Kinetic characterization using β-apo-8′-carotenal as substrate revealed, for OeCCD1, a K_m of 0.82 mM, V_max of 2.30 U/mg (k_cat = 3.35 s⁻¹), and k_cat/K_m of 4.09 mM⁻¹·s⁻¹, whereas InCCD1 displayed K_m = 0.69 mM, V_max = 1.22 U/mg (k_cat = 1.82 s⁻¹), and k_cat/K_m = 2.64 mM⁻¹·s⁻¹. The optimization of expression parameters, as well as the systematic evaluation of temperature, pH, solvent, and metal ion effects, provided further insights into the stability and functional diversity within the plant CCD1 family. Overall, these findings offer promising enzymatic tools for the sustainable production of β-ionone and related apocarotenoids in engineered microbial cell factories. Full article

Eocene magmatic systems contemporaneous with world-class Carlin-type Au deposits in Nevada (USA) have been proposed by some researchers as a key ingredient for Au mineralization, though evidence conclusively demonstrating their genetic relationship remains tenuous. This study provides the first direct evidence of the pre-eruptive metal budget of volatile- and metal-charged silicic magmas coincident in time (~41 to 34 Ma) and space (within 5 km) with Carlin-type Au deposits. We characterize the pre-eruptive metal fingerprints of these diverse magmatic systems to assess their potential as sources of metals for Carlin-type Au mineralization. Metal abundances from quartz-hosted melt inclusions (Au, Te, Ag, Sb, Tl, Mo, W, Sn, As, Pb, Co, Cu, Ni, and Zn) characterized in situ by SHRIMP-RG and LA-ICP-MS represent our best (and only) estimates for the pre-eruptive metal budget in these systems. Median metal concentrations are generally within one order of magnitude of average upper crust and average continental rhyolite values. But there are two notable exceptions, with median Au contents extending >1 order of magnitude higher than average upper crust and median Cu contents ranging >1 order of magnitude lower than upper crust. Despite this, melts contain lower Au/Cu (<0.1), Au/Ag (<5), and Au/Tl (<0.3) than most ore-grade Carlin-type rock samples and quartz-hosted fluid inclusions, regardless of their age and timing relative to nearby Carlin-type Au mineralization. The metal fingerprints of these magmatic systems, defined both by traditional and multivariate compositional data analysis techniques, are distinct from one another. Yet none are particularly specialized, e.g., high Au/Cu, in terms of being ideal ingredients as postulated by magmatic models for Carlin-type Au mineralization. Magmatic Au contents do not appear to be correlated with rhyolite “flavors” in the way that Cu, Sn, and Nb contents are. Fluid/melt partitioning modeling and magma volume estimates support the idea that a diverse array of non-specialized silicic magmas could feasibly contribute some or potentially all of the Au, Ag, and Cu in Carlin-type systems. The compositional diversity among contemporaneous magmatic systems could possibly contribute to some of the diversity observed across Carlin-type Au districts in Nevada. Full article

Fish oil is one of the most popular dietary nutritional supplements. Reports on the qualities of fish oils from Chinese markets are scarce, although the consumption of fish oil products in China is huge and increasing. This study systematically investigated the qualities of commercial encapsulated fish oils (CFs) and bulk fish oils (BFs) from Chinese markets, including oxidative level, sensory quality, color, metal element content, and unsaturated fatty acid content. Significant quality variations were observed both among individual CFs and between BFs: 65.2% of CFs (excluding one flavored sample) and one BF sample met China’s Grade II fish oil oxidation product standards; 80.8% of CFs and three BFs were within regulatory limits for heavy metal contamination. A distinct fishy odor was detected in four CFs and one BF sample, while a pronounced rancid odor was observed in one CF sample. The EPA contents in 64% of CFs and DHA contents in 48% of CFs met their labeled claims. Furthermore, these five quality parameter categories demonstrated non-significant intercorrelations, with the fish oil unit price being independent of quality. These findings indicated that most BFs require refinement, and CFs require implementation of low-temperature dark storage/transportation protocols. This study provided comprehensive quality benchmarks for fish oil production and marketing. Full article

Beer, the most popular alcoholic beverage, poses health risks for individuals with gout and hyperuricemia due to its high purine content. Herein, we identified a novel purine nucleoside phosphorylase (AbPNP) from the edible mushroom Agaricus bisporus and heterologously expressed it in Pichia pastoris. The recombinant AbPNP exhibited optimal activity at 60 °C and pH 7.0, retaining >80% activity at pH 6.0–9.0 and >85% activity after 3 h at ≤60 °C. Kinetic analysis revealed high catalytic efficiency (kcat/Km = 2.02 × 10⁶ s⁻¹⋅M⁻¹) toward inosine, with strong resistance to metal ions except for Co²⁺ and Cu²⁺. The application of AbPNP (1.0–5.0 U/mL) during wort saccharification reduced purine nucleosides by 33.54% (from 151.53 to 100.65 mg/L) while increasing yeast utilization of free purine bases. The resulting beer showed improved fermentation performance (alcohol content increased by 3.6%) without compromising flavor profiles. This study provides the food-grade enzymatic strategy for low-purine beer production, leveraging the GRAS status of both A. bisporus and P. pastoris. Full article

The advantages of pottery jars in the aging process of Baijiu are evident, but the impact of their material composition and pore structure on the flavor of Baijiu has not been widely studied. This study systematically analyzed the effects of six types of pottery jars on metal ions and flavor substances during the storage process of Maotai-flavored Baijiu. It was found that changes in the content of Fe and Zn metals, as well as pore parameters in the jars, significantly affected the content of AL, Mg, K, Na, and Ca ions in Baijiu. Based on three feature ranking methods and three machine learning models, a feature selection method related to flavor substances was established, identifying the key features (i.e., key metal ions) for each flavor group. The final key features of each flavor group can accurately predict the corresponding flavor substance content (Rp² > 0.87). The comprehensive analysis results indicate that the increase in the content of Fe, as well as the increases in P-max and P-min in the pottery jar, collectively promoted the formation of three flavor groups represented by ethyl valerate (G2), ethyl lactate (G7), and ethyl linoleate (G10), with an increase of 3% to 5%. In contrast, the increase in Zn inhibited the formation of the flavor group represented by 2,3-butanediol (G3), with a decrease of 14%. These results further clarify the impact of pottery jar formulations on the changes in flavor substances and provide a more effective method for analyzing the influence mechanism of jars on Baijiu. Full article