Search Results (1,575)

The functional performance and structural integrity of natural rock materials under fluctuating environmental stressors are pivotal for their advanced applications. As a non-ionizing and radiation-free technology, terahertz (THz) spectroscopy offers a safe and promising alternative for non-destructive testing (NDT), uniquely capable of being deployed in open and unshielded environments. However, limited penetration depth, exacerbated by both the dense geological matrix and the extreme sensitivity of THz waves to moisture states, has long hindered its widespread application in rock characterization. This study establishes a quantitative Terahertz Time-Domain Spectroscopy (THz-TDS) framework to characterize four lithologies under drying–wetting cycles. Exponential signal attenuation across thicknesses was quantified based on the Beer–Lambert law, with attenuation coefficients ranging from 0.15 to 0.74 per millimeter. Planar transmission imaging successfully visualizes lithologic and moisture-dependent heterogeneity: limestone exhibits a dense, homogeneous structure with stable amplitude distribution; sandstone and purple sandstone show parallel statistical trends, reflecting uniform pore networks; and granite demonstrates the most pronounced imaging contrast under varying moisture states, driven by complex grain-boundary scattering. The findings reveal that THz transmission is dictated by the synergistic effects of mineral compositions and pore structures: scattering at grain boundaries and fractures leads to significant energy dissipation, whereas clay-rich lithologies exhibit the highest sensitivity to moisture variations due to water adsorption and interfacial polarization effects. As an exploration of THz technology in the non-destructive evaluation of rock materials, these findings establish an analytical framework for the quantitative assessment of microstructure evolution. Full article

Hops (Humulus lupulus L.) is a plant species with a multitude of uses in medicine, food science and agriculture. Xanthohumol, the major prenylflavonoid in hop cone extract, possesses anti-cancer activity. Xanthohumol also exhibits strong antimicrobial activity against Gram-positive bacteria (e.g., S. aureus), but not against Gram-negative bacteria. Xanthohumol can reduce blood glucose levels and body fat in obese male rats (not females), and mature hop bitter acids (MHBAs) have been found to decrease visceral and abdominal human fat. Xanthohumol can increase bone mineral density, decrease osteoclast numbers, and protect osteoblasts from oxidative stress in osteoporotic mice. Further clinical research, xanthohumol and bitter acids could be sourced from hop cone extracts to formulate novel drugs that can successfully treat a variety of diseases and potentially replace current therapies that have negative effects. In the food industry, hop cone extracts are mainly used in the brewing industry, with 98% of the world’s hop cones being used in brewing beer. Hop cone extracts are also used as food/drink preservatives due to their antimicrobial abilities, as previously mentioned, although there is less of a need for hops in extending food/drink shelf-life. Finally, hop cone extracts have several uses in agriculture, mainly as pesticides. For example, hop extracts can kill varroa mites, a parasite that impairs honeybee health. This benefits honeybee farmers as increased bee survival means more honey production, increasing profits. Overall, this review paper brings together recent studies that highlight hop extracts as valuable bioactive compound mixtures with many useful applications. Full article

Zearalenone (ZEN) is a pervasive mycotoxin contaminating global food and feed. While enzymatic degradation offers a promising, specific, and eco-friendly strategy for mycotoxin mitigation, the biotransformation of ZEN within acidic food matrices remains challenging due to the intrinsically low activity of zearalenone lactonase (ZENG). In this work, we synthesized a ZENG–hydroxyapatite (Ca₁₀(PO₄)₆(OH)₂) hybrid nanoflower (CaNF) via biomineralization under alkaline conditions. Compared to free ZENG, the as-prepared biohybrid nanoflower exhibited markedly enhanced acid tolerance and catalytic activity, achieving a 12-fold increase in ZEN degradation efficiency at pH 5.0. Furthermore, the biohybrid nanoflower demonstrated robust performance in various acidic food matrices, including corn juice, wort, beer, and corn steep liquor. This study presents a powerful enzymatic tool for the efficient biotransformation of ZEN in acidic food-related systems. Full article

Despite increasing interest in beer-derived umami peptides, their formation during lager beer fermentation and their potential roles in receptor recognition and sensory perception remain insufficiently understood. Therefore, this study combined peptidomics, in silico screening, receptor-oriented analysis, and sensory evaluation to investigate the dynamic changes in umami-related peptides throughout lager beer fermentation and to explore their possible sensory relevance. Peptide profiles varied markedly across the fermentation process, indicating continuous proteolysis and dynamic restructuring of the peptide pool. From these profiles, candidate umami peptides were screened, and representative short peptides with plausible receptor-binding characteristics were selected for further evaluation. These peptides showed measurable taste activity and were mainly associated with modulation of the umami–bitterness–aftertaste dimension, whereas their effects on aroma and overall balance were limited. In addition, the abundance of umami-related peptides was positively associated with perceived umami intensity. Overall, the results suggest that fermentation-derived peptides may contribute to taste perception in lager beer and provide a basis for further studies on flavor-oriented brewing and process regulation. Full article

The brewing industry remains at the forefront of technological innovation, with growing interest in alternative yeasts. Saccharomyces cerevisiae var. boulardii, a well-established probiotic yeast, has attracted attention for its potential to produce probiotic-enriched beers, offering an option for moderate consumers seeking functional beverages. This mini-review brings together current research on the use of S. boulardii in craft brewing, focusing on fermentation performance, flavour and sensory characteristics, and potential health-related functions. While often regarded as a variant of S. cerevisiae, S. boulardii shows comparable or greater cell growth, increased acetic acid production at the expense of glycerol, and lower alcohol yield compared to S. cerevisiae. Despite these differences, beers brewed with S. boulardii exhibit similar volatile compound profiles and sensory characteristics to those produced with S. cerevisiae. In terms of health-related attributes, S. boulardii-fermented beers show higher antioxidant activity, the presence of malto-oligosaccharides with prebiotic potential, and the ability of yeast to survive both storage and gastrointestinal transit. Strategies explored to optimise its brewing performance and customer acceptance include co-fermentation with S. cerevisiae, modified mashing protocols, and natural flavour additions. Overall, the available evidence supports S. boulardii as a promising yeast for developing probiotic-enriched beers. Further research is needed to validate current findings at commercial scales, investigate host–microbiome interactions following beer consumption and develop strategies that balance probiotic efficacy and desirable beer appearance over shelf life. The paper may assist brewers in making informed decisions about deploying S. boulardii, aligning consumer interest in functional beverages with the enjoyment of beer. Full article

This study aimed to identify umami peptides in non-alcoholic beer and clarify their potential contribution to taste reconstruction and aftertaste improvement. Peptides were profiled by RPLC-Q-TOF-MS and screened using machine learning prediction, molecular docking, MM-GBSA analysis, and sensory validation. Under the criteria of −10logP ≥ 15 and ALC ≥ 90.00%, 2081 peptides were identified. Among them, 122 potential umami peptides were predicted, and 117 peptides were successfully docked with the T1R1/T1R3 umami receptor. The docked peptides were mainly short to medium oligopeptides, especially tetrapeptides and pentapeptides, which accounted for 40.17% and 35.90%, respectively. Based on docking score, structural diversity, and peptide length distribution, CTGAA, IDQILG, KDTHP, QRQ, and EITGR were selected as representative candidates. These peptides showed favorable receptor binding, mainly supported by hydrogen bonding, electrostatic interactions, and local hydrophobic contacts. Sensory validation further showed that the 5 peptides improved umami and aftertaste cleanliness to different degrees. Umami intensity increased by 7.58% to 22.73%, while aftertaste cleanliness increased by 5.80% to 17.39%. Among them, CTGAA showed the strongest umami enhancement, and QRQ produced the greatest improvement in aftertaste cleanliness. These results suggest that selected umami peptides may contribute to flavor reconstruction in non-alcoholic beer by enhancing umami perception and improving aftertaste quality. Full article

Ensuring sustainable food production for a growing population requires robust tools like the Life Cycle Assessment (LCA), despite the fundamental complexities characterising the agri-food sector. This study evaluates the environmental impacts of beer and bread production, two important sectors, within a circular economy framework using the LCA. The analysis focuses on innovative products: bread incorporating brewery-spent grain and beer brewed from unsold bread. The study follows a cradle-to-gate approach, covering the entire upstream supply chain, including cultivation, milling, malting, and ingredient production. Cultivation emerges as the primary environmental hotspot in both systems. In bread production, the bakery and proofing phases also show high impacts, while in brewing, packaging is the dominant contributor, followed by boiling and hopping. For co-product processing, drying and transport are critical hotspots. Compared with conventional products, innovative circular products generally show lower environmental impacts, with exceptions related to organic cultivation and allocation constraints. Circular strategies notably reduce land use and marine eutrophication in most organic cases. Overall, the fully circular scenario outperforms the Conventional System in 13 impact categories, supporting the environmental potential of circular approaches in both sectors. Full article

The integrating sphere with sample inside (ISSI) method is useful for absorption spectroscopy of scattering samples, but the measured absorbance (${\mathrm{A}}_{\mathrm{meas}}$) becomes nonlinear with dye concentration (c) because the sample is placed inside the sphere. This study modeled the ${\mathrm{A}}_{\mathrm{meas}}-c$ relationship for ISSI using a cylindrical cell (CC) and a Brewster cell (BC) with simple analytical expressions based on the fraction of light not passing through the sample and the effective weights of light passing through it multiple times. Four aqueous dye solutions—Trypan Blue, Brilliant Blue FCF, Tartrazine, and New Coccine—were used as non-scattering samples. For CC, a single-pass model reproduced the measured relationship well for all dyes, and linearity was maintained in the low-absorbance region (up to approximately half of the saturation absorbance, $A_{\mathrm{m}\mathrm{a}\mathrm{x}}/2\approx 0.67$ Abs). For BC, the same low-absorbance region (up to approximately $A_{\mathrm{m}\mathrm{a}\mathrm{x}}/2\approx 1.21$ Abs) also exhibited practical linearity, but the full relationship including saturation required a multiple-pass model. Model selection based on adjusted RMSE and AICc identified the 3-pass model as the minimum sufficient model for BC. The saturation absorbance ${\mathrm{A}}_{\max }$ was on average 1.81 times higher for BC than for CC (corresponding to an approximately 12-fold expansion in linear intensity ratio), and the upper concentration limit of the linear approximation was on average 1.85 times higher. These results demonstrate that BC extends the measurable concentration range while preserving practical low-absorbance linearity. In addition, the wavelength dependence of ${\mathrm{A}}_{\max }$ observed at short wavelengths is attributed primarily to the reduced reflectance of the BaSO₄ integrating-sphere wall rather than to the refractive-index dispersion of the quartz cell. Full article

The style of a beer is determined by the combination of malts and hops, and the type of yeast used. The incorporation of date fruits into the fermentation process with non-conventional yeasts such as Lachancea spp. results in effective fermentation, influencing the kinetic parameters of yeast growth and prompting different physicochemical properties in the resulting beverage. The brewing process for a sour beer with Lachancea spp. yeast was optimized using a central composite rotational design and response surface methodology, and the growth kinetics were calculated. The optimal conditions required 500 g of dates, incorporated 59.46 h after starting the fermentation process. The results revealed a total phenolic content of 254.81 mg GAE/g, and the amount of titratable acidity was 2.66%. Under favorable operating conditions, the growth kinetic parameters of Lachancea spp. yeast revealed a rate of 0.78 μ.h⁻¹ and a growth constant of 3.29 k (g/h). The addition of dates 60 h into fermentation with Lachancea spp. allows for technical control of acidity and efficient fermentation kinetics for the creation of sour craft beers. Full article

Fourier Transform Infrared Spectroscopy (FTIR) is increasingly used for the mineralogical characterization of complex materials such as ceramics, soils and clays. However, its quantitative application remains limited due to spectral overlapping and matrix effects in solid samples. In this study, a semi-quantitative mineralogical analysis method based on Attenuated Total Reflectance FTIR (ATR-FTIR) is proposed. The method uses the principal absorption band of calcite as a normalization reference in order to estimate relative molar absorptivity coefficients according to the Lambert–Beer law. Experimental spectra obtained from pure minerals and laboratory mineral mixtures were analyzed using derivative spectroscopy and numerical optimization. The correlation between experimental and calculated spectra was performed using the GAMS equation modeling environment and the nonlinear programming solver CONOPT. Mineral mixtures were used to determine the minimum detectable band intensity and detection limits. Bands with normalized intensities lower than 0.01 were discarded, corresponding to a detection limit of approximately 7 mol%. Application of the proposed methodology to ceramic coatings samples from Teruel and Castellón demonstrated that the FTIR spectra are dominated by aluminosilicate bands associated with quartz and clay minerals, together with carbonate features attributable to calcite. These results are consistent with the expected mineralogical composition of ceramic raw materials and confirm the suitability of the method for analyzing natural samples. However, the ATR-FTIR method presents several inherent limitations that may affect both the accuracy and reproducibility of spectral data. Full article

(1) Background: Flavored craft beer is favored for its diverse and distinctive aroma compounds; however, traditional fermentation processes are often plagued by poor yeast flocculation, which leads to substantial beer losses and compromised production efficiency. Yeast immobilization technology has emerged as a promising strategy to improve fermentation performance, shorten the primary fermentation period, and mitigate beer loss. (2) Methods: In this study, a natural material–based carrier was developed for the immobilization of yeast, and its application in mango craft beer fermentation was systematically investigated. The optimal fermentation conditions were screened, and the physicochemical properties, nutritional composition, and volatile flavor profiles of the resulting mango craft beer were comprehensively evaluated. (3) Results: The results showed that the maximum mass gain of yeast after immobilization on the natural carrier reached 13.3%. Compared with free yeast, the immobilized yeast exhibited a 1.58-fold higher average extract consumption rate and a 1.39-fold higher alcohol production rate based on the overall fermentation system, while the primary fermentation period was shortened by approximately 33%. Under the optimized fermentation conditions, the mango craft beer achieved a sensory score of 81 points, with a β-carotene retention rate of 91.25%. Furthermore, the mango craft beer exhibited a more diverse profile of volatile flavor compounds and enhanced nutritional composition compared with the control. (4) Conclusions: Overall, fermentation conditions were optimized using Response Surface Methodology (RSM) based on Box–Behnken Design (BBD). Natural immobilization carrier developed in this study effectively enhanced yeast fermentation efficiency and shortened the primary fermentation cycle, and these findings demonstrate its significant potential for cost reduction and efficiency enhancement in the production of flavored craft beer, providing a practical technical support for the industrial application of natural carrier-based yeast immobilization technology. Full article

Free-space optical (FSO) communication is an attractive high-capacity wireless technology for terrestrial, aerial, and satellite links. However, FSO performance is strongly affected by multiple impairments, including path loss, turbulence attenuation, pointing errors, and equipment loss. Therefore, accurate performance evaluation requires channel modelling that accounts for both deterministic power losses and stochastic channel effects. This paper presents a comprehensive and structured review of FSO channel modelling, covering the transmission, propagation medium, and receiver sections. The composite channel response is represented using a mathematical formulation. Commonly used FSO models are reviewed and organised, including Beer–Lambert and geometrical loss, Kim and Kruse path loss models, Lognormal, Gamma–Gamma, K, and Málaga distributions, along with pointing-error and angle-of-arrival models. Each model is explained in terms of its physical meaning, assumptions, and applicable operating conditions. Lastly, a numerical example is presented to demonstrate how deterministic losses and stochastic channel effects can be combined in FSO performance evaluation. Full article

Wood is a material frequently used in the production of alcoholic beverages. Oak barrels have been used to store wines, beers, and spirits for generations. Nowadays, beverages are increasingly matured in the presence of staves and chips from various wood species. The aim of this article was to describe the impact of different wood species and their thermal processing conditions on the quality of alcoholic beverages. The article describes the chemical composition of wood and the compounds formed during toasting at various temperatures. It also lists the volatile compounds extracted from wood for alcoholic beverages, along with their sensory thresholds and their impact on olfactory sensations. Attention was drawn to potentially harmful substances formed during wood toasting, including aromatic hydrocarbons and polycyclic aromatic hydrocarbons. The amounts of compounds extracted from wines, beers, and spirits from different wood species and toasted under different conditions were compared. Quercus barrels contribute to higher lactone concentrations in beverages, which have a coconut aroma. Cherry, acacia, and ash wood increase the concentration of volatile phenols in beverages. The use of staves and chips shortens the maturation time and facilitates the design of beverages with specific sensory characteristics. Full article

Quinoa contains all the essential amino acids for human nutrition, which is also known to be gluten-free. In this research, black, red, white, and gray quinoa were germinated to ferment beers. The effects of germination as a bioprocess on the nutritional profile, anti-nutrients, and flavor development in quinoa beers were systematically investigated, and a comprehensive comparison was made with two commercially popular beers. The results indicated that the optimal germination time for quinoa in beer production was 48 h. Germination significantly increased the contents of polyphenols (255.9 mg/L in white quinoa beer) and flavonoids (404.34 mg/L in red quinoa beer), which enhanced the antioxidant activity of the beers. Furthermore, the levels of protein and γ-aminobutyric acid were elevated through germination. Notably, germination markedly improved the potential nutritional accessibility of the beers through reducing the anti-nutritional factors, including phytic acid, tannins, and trypsin inhibitor. In terms of flavor, quinoa beers developed a unique and pleasant aromatic profile, characterized by compounds such as ethyl octanoate, ethyl 9-decenoate, and ethyl pentadecanoate, which distinguished them from commercial beers. In conclusion, germinated quinoa can serve as a high-quality brewing material for producing beer with enhanced nutritional value, reduced anti-nutrients, and improved flavor characteristics. Full article

The Brazilian craft beer market has experienced continuous growth, increasing operational challenges for small- and medium-sized breweries that frequently rely on empirical and spreadsheet-based production routines. These practices often lead to inefficient resource allocation, production instability, and sustainability concerns. This study proposes an integrated analytical framework combining Machine Learning (ML) and Operations Research (OR) to improve demand forecasting and production planning. The methodology is based on a synthetic dataset calibrated to the operational conditions of a Brasília-based craft brewery, incorporating realistic demand patterns such as seasonality, trend, and intermittency across multiple SKUs over an 18-month horizon. Forecasting models—including Moving Average, Single Exponential Smoothing, and a global ML-based proxy—were evaluated using rolling-origin validation. The resulting probabilistic forecasts were integrated into a capacity-constrained optimization model based on linear programming, extended with risk-aware decision-making using Conditional Value-at-Risk (CVaR). The results indicate that the ML-based approach achieved competitive forecasting performance (sMAPE = 5.83% and MAE = 11.76) while enabling the generation of capacity-feasible and risk-aware production plans aligned with service-level targets. The integration of probabilistic forecasts into the optimization model allowed explicit trade-offs between cost, service level, and resource utilization. The main contribution of this study lies in demonstrating how the integration of predictive and prescriptive analytics can support more sustainable production planning in resource-constrained manufacturing environments. By replacing ad hoc spreadsheet routines with a closed-loop decision-support system, the proposed framework advances the literature on data-driven PPC and provides practical guidance for SMEs operating under uncertainty. Full article