Search Results (68)

Wild ales represent a diverse category of spontaneously fermented beers, influenced by complex microbial populations and variable ingredients. This study employed an integrated metabolomic profiling approach combining proton nuclear magnetic resonance (¹H NMR) spectroscopy, liquid chromatography–mass spectrometry (LC-MS), and spectrophotometric assays (DPPH and FRAP) to characterize the molecular composition and antioxidant potential of 22 wild ales from six countries. A total of 53 compounds were identified and quantified using NMR, while 62 compounds were identified by using LC-MS. The compounds in question included organic acids, amino acids, sugars, alcohols, bitter acids, phenolic compounds, and others. Ingredient-based clustering revealed that the addition of dark fruits resulted in a significant increase in the polyphenolic content and antioxidant activity. Concurrently, herb-infused and light-fruit beers exhibited divergent phytochemical profiles. Prolonged aging (>18 months) has been demonstrated to be associated with increased levels of certain amino acids, fermentation-derived aldehydes, and phenolic degradation products. However, the influence of maturation duration on the antioxidant capacity was found to be less significant than that of the type of fruit. Country-specific metabolite trends were revealed, indicating the influence of regional brewing practices on beer composition. Correlation analysis was employed to identify the major contributors to antioxidant activity, with salicylic, dihydroxybenzoic, and 4-hydroxybenzoic acids being identified as the most significant. These findings underscore the biochemical intricacy of wild ales and exemplify metabolomics’ capacity to correlate compositional variation with functionality and authenticity in spontaneously fermented beverages. Full article

Beer is the third most popular beverage in the world, and its production is distributed uniformly between the biggest continents. Considering the environmental aspects, the utilization of brewing by-products, mainly brewers’ spent grain (BSG), is essential on a global scale. The beer revolution, lasting over a few decades, significantly diversified the beer market in terms of styles, and therefore, also its by-products, which should be characterized appropriately prior to further application. Herein, the presented study investigated the unprecedented number of 22 different variants of brewers’ spent grain, yielded from the production of various beer styles, enabling their proper comparison. A comprehensive by-product characterization revealed an almost linear relationship (Pearson correlation coefficients exceeding 0.9) between the color parameters (L*, a*, browning index) of beer and generated spent grain, enabling a prediction of BSG appearance based on beer color. Applying wheat or rye malts increased the content of extractives by over 40%, reducing cellulose content by as much as 45%. Thermal treatments of malts (kilning or smoking) also reduced extractive content and limited antioxidant activity, often by over 30%. A lack of husk for wheat or rye reduced the crystallinity index of spent grain by 21–41%, while the roasting of barley efficiently decomposed the less stable compounds and maintained the cellulose crystalline structure. All the analyzed BSG samples were characterized by low volatile emissions and very limited antimicrobial activity. Therefore, their harmfulness to human health and the environment is limited, broadening their potential application range. Full article

Three types of solid waste are produced during beer fermentation: spent grain, hot trub, and residual yeast. While the first is used as livestock feed, the seconds has not yet found any real reapplication in the field of circular economy. The aim of this work is to study and characterize these two brewing wastes, i.e., hot trub and residual yeast, to evaluate their potential reuse in the agricultural field. Samples from top-fermented and bottom-fermented beers were chemically investigated. Initially, the safety was assessed via multi-detection analysis of 57 mycotoxins, and all samples were deemed safe. Subsequently, the chemical and elemental composition was examined via ICP-MS and microanalysis, along with phenolic compounds and antioxidant activity via HPLC and spectrophotometric determinations, to achieve a thorough characterization of these waste samples. The C/N ratio of residual yeast from top-fermented beer and hot trub of the bottom-fermented one were near the optimal one (10:1). This research marks an initial step towards repurposing brewery waste materials as fertilizers. The subsequent steps will involve the formulation and field trials. Full article

The utilization of alternative cereals for brewing beer has garnered significant interest in contemporary times. The utilization of alternative cereals as adjuncts has great potential for creating novel beer flavour profiles and cost savings. Brown rice (BR) is the unpolished rice grain that retains its outer layer post-hulling and is nutritionally superior to polished rice (PR). The utilization of BR in beer production remains unexplored, with its brewing attributes in comparison to PR yet to be elucidated, probably due to the potential adverse impact on beer flavour. This study involves incorporating PR and BR as adjuncts in a 40% ratio, alongside 100% Pilsen malt (PM) beer as the control, to contrast the brewing attributes (physicochemical indicators, antioxidant attributes, volatiles, and sensory analysis). Raw material analysis results showed that BR contains starch (72.97%), protein (6.85%), fat (3.38%), and ash (1.04%). The protein content of PR (4.12%) was lower than that of BR (6.85%), attributed to the absence of bran in PR, resulting in a reduced free amino nitrogen (FAN) content in its wort. Furthermore, it was observed that 40% BR beer showed enhanced antioxidant properties (0.55 mmol TE/L for DPPH and 0.75 mmol TE/L for ABTS) in comparison to 40% PR beer (0.12 mmol TE/L for DPPH and 0.4 mmol TE/L for ABTS). The changes that occurred in volatile and sensory analysis indicated discernible modifications in beer flavour consequent to the partial substitution of barley malt with BR. These findings show BR is an appropriate brewing adjunct. Full article

Beer is one of the most widely consumed alcoholic beverages and is rich in nutrients. Meanwhile, bread waste is a major contributor to global food waste. This study investigated substituting up to 50% of malt with whole wheat bread in American lager, Indian pale ale, and Bavarian weiss ale to reduce bread waste and enhance beer’s nutritional profile. The study assessed physicochemical properties, bioactive compounds, and volatile profiles of bread-based beers versus traditional malt-based brews. Results showed that bread beers maintained key properties while increasing bioactive compounds, especially in Bavarian weiss, which had higher total polyphenol content (1.04 mg GAE mL⁻¹ compared to 0.507 mg GAE mL⁻¹). Antioxidant activity in weiss beer also increased (2.007–2.057 μMol DPPH mL⁻¹ relative to 0.68–1.75 μMol DPPH mL ⁻¹ in 100% malt weiss). PCA analysis highlighted a distinct bioactive profile in bread beers, with elevated phenylethyl alcohol and ethyl octanoate. Substituting malt with bread was feasible, producing beers of comparable quality and potential health benefits. These findings support bread as a sustainable, cost-effective malt alternative, reducing waste and enhancing beer within a circular economy framework. Full article

This paper explores the broad probiotic and functional properties of two non-Saccharomyces strains (MI120 and MI125) and one Saccharomyces cerevisiae BB06 strain (as a reference probiotic). Torulaspora delbrueckii MI120 and Starmerella bacillaris MI125 were identified via 5.8S rDNA sequencing. All the strains survived well in simulated gastrointestinal conditions and had strong antioxidant activity (>68%). S. bacillaris MI125 excelled in antimicrobial activity against Gram-positive and Gram-negative bacteria. S. bacillaris MI125 and Sacch. cerevisiae BB06 resisted all the tested antibiotics. No strain displayed hemolytic behavior. The freeze-dried yeast strains achieved survival rates between 76.62% and 93.38%. Based on our physiological characterization analysis (carbon assimilation, ethanol tolerance, acetic acid and H₂S production, temperature and low pH tolerance, enzymatic pattern, and killer phenotype), all the strains showed interesting attributes, with Sacch. cerevisiae BB06 fermenting vigorously in malt extract medium. Beer fermented with T. delbrueckii MI120 had the highest phenolic content (96.02 μg GAE·mL⁻¹) and antioxidant activity (90.43%), matching commercial Sacch. cerevisiae US-05 in sensory traits such as taste and aroma. However, after two months in bottled beer, the yeast viability decreased to 2–3 log CFU·mL⁻¹. The pilot brewing and the assessments of the strains’ technological, physico-chemical, and sensorial properties confirmed their suitability for industrial brewing. Overall, T. delbrueckii MI120 emerges as a promising brewing strain, and S. bacillaris MI125 is a potential probiotic. Full article

Industrial residues are sources of functional biopolymers with interesting properties for textile applications. This study aims to evaluate the impact of enzymatic pre-treatment on oil yield and phenolic compounds’ content in an aqueous extraction process, as well as the functional properties incorporated into textiles. This research investigated the influence of residue granulometry, biomass percentage, and the application of enzymatic pre-treatment with different enzymes (cellulase, pectinase, xylanase) individually or in combination. Chestnut hedgehog (CH), tobacco plant stems (TPSs), vine shoot trimmings (VSTs), and beer spent grain (BSG) were explored. For textile functionalization, the extracted oils were incorporated into a bio-based formulation and applied on cotton fabric through pad-dry-cure. For CH, the pre-treatment with cellulase and xylanase achieved an oil yield of 149 and 148 mg oil/mL extract, respectively. With the combination of both enzymes, the richest oil in phenolic compounds was extracted: 1967.73 ± 16.86 mg GAE/g biomass. CH and TPS oils presented an antioxidant activity above 60%, and the functionalized textiles also showed the highest antioxidant potential and a UPF of 30. The textiles presented water repellence and washing fastness. This study demonstrates a sustainable oil extraction method and its potential application in the development of functional textiles. Full article

(1) Background: Over 90% of hop crops are currently used in beer production, with a small part used in the cosmetics and pharmaceutical industries. Spent hops as a waste product contain one of the strongest antioxidants, xanthohumol. The aim of the study was to purify spent hop extracts by magnetic dispersive extraction using iron oxide nanoparticles (IONP) to obtain pure xanthohumol; (2) Methods: The extract from the waste product obtained after supercritical carbon dioxide extraction of hops was prepared by ultrasound-assisted extraction utilizing different solvents, i.e., ethyl acetate, propanol, acetone, 80% methanol, ethyl acetate-methanol (1:1, v/v), and propanol-methanol (1:1, v/v). The hydrodynamic diameters and zeta potential of IONPs before and after incubation were measured by dynamic light scattering (DLS). The extracts were analyzed by reversed-phase high-performance liquid chromatography (HPLC). Isolated xanthohumol was identified based on the DAD spectrum in the range of 200–600 nm and by Fourier transform infrared spectroscopy/attenuated total reflectance (FT-IR/ATR); The antioxidant activity of extracts before and after incubation with IONPs was assessed using SNPAC (Silver Nanoparticle Antioxidant Capacity), DPPH (2,2-diphenyl-1-picrylhydrazyl radical), and FRAP (Ferric Reducing Antioxidant Power) assays, as well as total phenolic content (TPC) and total flavonoid content (TFC). (3) Results: The amount of added IONPs, the kind of solvent, and the contact time of the extract with nanoparticles were optimized. We found that 80% MeOH extract after incubation with IONPs (865 µg IONPs/g of spent hops) at room temperature for 48 h contains 74.61% of initial xanthohumol content, providing a final xanthohumol concentration of 43 µg mL⁻¹. (4) Conclusions: The proposed method of magnetic dispersive extraction using IONPs allows for the purification of spent hops extract and obtaining a pure product, namely xanthohumol, with a wide potential for practical applications in medicine, pharmacy, cosmetics, and agriculture. This is clear evidence of the usefulness of IONP as an effective sorbent. The method allows the use of residues from the brewing industry, i.e., the biomass of used hop cones to obtain a valuable substance. Full article

Xanthohumol (XN), a bioactive plant flavonoid, is an antioxidant, and as such, it exhibits numerous beneficial properties, including anti-inflammatory, antimicrobial, and antioxidative effects. The main dietary source of XN is beer, where it is introduced through hops. Although the concentration of XN in beer is low, the large quantities of hop-related post-production waste present an opportunity to extract XN residues for technological or pharmaceutical purposes. The presented study focuses on the role of XN in the prevention of neurodegenerative diseases, analyzing its effect at a molecular level and including its signal transduction and metabolism. The paper brings up XN’s mechanism of action, potential effects, and experimental and clinical studies on Alzheimer’s disease (AD), Parkinson’s disease (PD), and amyotrophic lateral sclerosis (ALS). Additionally, challenges and future research directions on XN, including its bioavailability, safety, and tolerance, have been discussed. Full article

Craft beer has gained popularity due to its unique sensory characteristics and complex matrix with nutritional and potential health benefits. Studies linking beer consumption to skin conditions are limited, however, the high content of bioactive compounds is related to biological activities such as antibacterial, anti-inflammatory, anti-oxidative, and anti-carcinogenic. This study aims to evaluate the antioxidant, photoprotective and metabolic activity in human keratinocytes (HaCaT). Eighteen craft and four industrial beers were analyzed after dealcoholizing, degassing and freeze-drying. Total phenolic content (TPC) and antioxidant activity were determined. The most promising craft beer was studied for its photoprotective and metabolic activity. An India Pale Ale beer (ALM-IPA) presented the second best TPC (8.96 ± 0.64 mg of GAE/g) and promising antioxidant activity by ABTS (IC₅₀ = 55.21 ± 4.68 µg/mL), H₂O₂ (IC₅₀ = 23.54 ± 1.53 µg/mL) and FRAP (53.74 ± 1.27 µmol TE/g) assays. Regarding photoprotective activity, a solar photoprotection factor of 48.85 ± 0.39 was obtained. ALM-IPA showed no cytotoxicity up to a concentration of 250 µg/mL after 24 and 48 h of incubation. The potential benefits of beer extracts on skin can be seen, but further studies are essential to corroborate the findings and guarantee the safety of the extracts. Full article

Lager yeast, which is mainly used for lager beer brewing, withstands significant oxidative stress during brewing process, leading to its rapid aging in serial beer brewing. Mitophagy plays a critical role in the antioxidant stress response of yeast. However, the relationship between mitophagy and the antioxidant capacity of yeast is still unclear. Previous studies indicated that ATG gene family in mitophagy significantly affects the antioxidant capacity of yeast cells in beer brewing. Herein, the expression of ATG8, ATG11, ATG32, DNM1, and MMM1 genes was regulated. The results showed that the overexpression of ATG8 and ATG11 significantly reduced the intracellular ROS contents to 52.05% and 22.57% of the initial state, respectively, and helped to maintain a high mitochondrial vitality during serial fermentation. Disruption of ATG8, ATG11 and ATG32 resulted in significant decrease in cell vitality when exposed to H₂O₂ stimulation. Meanwhile, the disruptions of these genes were detrimental to the balance of intracellular ROS. Excess DNM1 activity could affect the cellular energy balance and ATP depletion under prolonged stress conditions. The repression of MMM1 led to lower ATP levels during serial beer fermentation. The ATG8, ATG11, and ATG32 genes might be potential targets for regulating the antioxidant capacity of yeast. The current work provides new insights into improving the antioxidant capacity of yeast through mitophagy regulation. Full article

Beer is considered one of the most consumed beverages worldwide and a potential vehicle for probiotics. However, there are several technical challenges to overcome during the production and storage of beers, as probiotics must remain viable until the moment of consumption. Therefore, this work aims to discuss how the incorporation of probiotics improves or adds value to beer and which variables influence the viability of the process. This is a narrative review of the literature with research in the PubMed, Web of Science, and b-on databases for articles related to the incorporation of probiotics in beer and the variables that influence the process. The results demonstrated that the incorporation of probiotics into beer faces technical challenges such as probiotic selection, pH, the presence of alcohol, and beer’s production and storage temperatures. However, strategies such as immobilizing probiotics in alginate, alginate–silica, and durian husk powder, fermentation with the yeast Saccharomyces cerevisiae var. boulardii, and co-fermentation with probiotics permit us to overcome these barriers. Thus, incorporating probiotics into beer brings added value, potentially increasing antioxidant activity and phenolic compound content and providing unique flavors and aromas. Nevertheless, strict control of the technical conditions involved is necessary to ensure probiotic viability and the health benefits they confer. Full article

Background: Common hops (Humulus lupulus L.) play a key role in brewing, providing the bitterness, flavor, and aroma of beer, and are widely used in supplements for their antibacterial, anti-inflammatory, and antioxidant properties. However, despite their broad applications, the allergenic potential of common hops remains underexplored, particularly when compared to the closely related Humulus japonicus. This preliminary study aimed to investigate the allergenic potential of common hops and their potential cross-reactivity with common pollen allergens. Methods: The immunoreactivity of hop stalks, leaves, and cones was assessed using antibodies against major allergens from birch (Bet v1a), mugwort (Art v1), and timothy grass (Phl p5b), as well as three sera from pollen-allergic patients. Slot Blot analysis was performed using phosphate-buffered saline extracts from the stalks, leaves, and cones of three hop cultivars, while Western Blotting followed SDS-PAGE protein separation. Results: The results revealed significant immunoreactivity in native hop proteins, with diminished reactivity observed in denatured proteins. Cross-reactivity between hop proteins and major pollen allergens was confirmed, indicating that hop proteins may contribute to allergic sensitization in pollen-sensitive individuals. Conclusions: These findings underscore the potential allergenic risks associated with the consumption or exposure to hop-containing products. Full article

Of the three types of waste generated in beer processing, brewer’s spent grain (BSG) is the most abundant and has a high potential for valorization. In this work, defatted BSG (DB) was subjected to an extraction process with subcritical water at different temperatures to obtain extracts rich in phenols and the cellulosic fractions, which were also purified by using hydrogen peroxide (H₂O₂). The results showed that the dry extracts obtained at 170 °C were richer in phenolics (24 mg Gallic Acid Equivalent (GAE) g⁻¹ DB), but with lower antioxidant capacity (71 mg DB·mg⁻¹ 2,2-diphenyl-1-pikryl-hydrazyl). This extract also showed the highest antibacterial potential against L. innocua (80 mg·mL⁻¹) and E. coli (140 mg·mL⁻¹) than those obtained at lower temperatures. The purification of cellulose from the treated residues, using hydrogen peroxide, revealed that DB is a limited source of cellulose material since the bleached fractions showed low yields (20–25%) and low cellulose purity (42–71%), even after four bleaching cycles (1 h) at pH 12 and 8% H₂O₂. Despite this, the subcritical water extraction method highlights the potential of a simple process as a technological option to convert underutilized side streams like beer bagasse into added-value, potential ingredients for innovative food and pharmaceutical applications. Full article

Brewers’ spent grain (BSG) is the primary by-product of beer production, and its potential use in food products is largely dependent on its processing, given its moisture content of up to 80%. This study aimed to evaluate the effects of physical separation with ultrasound application on the color, total phenolic content (TPC), antioxidant activity, proximate composition, total dietary fibers, and particle size distribution of BSG powders. Wet BSG (W) was subjected to two processes: one without ultrasound (A) and one with ultrasound (B). Both processes included pressing, convective air-drying, sieving, fraction separation (A1 and B1 as coarse with particles ≥ 2.36 mm; A2 and B2 as fine with particles < 2.36 mm), and milling. The total color difference compared to W increased through both processes, ranging from 1.1 (B1 vs. A1) to 5.7 (B1 vs. A2). There was no significant difference in TPC, but process B powders, particularly B2, showed lower antioxidant activity against ABTS•+, likely due to the release of antioxidant compounds into the liquid fraction during pressing after ultrasound treatment. Nonetheless, process B powders exhibited a higher content of soluble dietary fibers. In conclusion, ultrasound application shows potential for further extraction of soluble fibers. However, process A might be more practical for industrial and craft brewers. Further studies on the use of the resulting BSG powders as food ingredients are recommended. Full article