High-sugar driven microbial dynamics in spontaneous fermentations of Lebanese cooked wines.

Development of a GMO-free de novo lager yeast with reduced phenolic off-flavor production through interspecific hybridization and UV mutagenesis.

Tannins in ruminant feeding: effects of tannin type and dosage on rumen fermentation, production performance, health, and sustainability.

This study presents the design and optimization of a laboratory-scale bubble column bioreactor (BCB) for bioethanol fermentation. Python-based simulations in Google Colab were employed to analyze mass transfer dynamics, hydrodynamic behavior, and reactor scale-up strategies under varying aeration rates. Although ethanol production is an anaerobic process, oxygen transfer analysis was conducted to characterize reactor performance and establish oxygen-limited conditions suitable for Saccharomyces cerevisiae fermentation, incorporating mass transfer modeling, reaction kinetics, process control, and sparger design to enhance fermentation efficiency. To further enhance fermentation efficiency, Response Surface Methodology (RSM) was applied following a two-stage optimization approach. A working volume of 500 mL was defined using fermentation kinetics, including an oxygen uptake rate of 1.1 g O₂/g cells, biomass yield of 0.5 g/g glucose, and kLa of 50 h⁻¹. A perforated plate sparger with six 1.2 mm orifices achieved a gas velocity of 90.3 m/s and 2.68 mm bubble size. Aeration was dynamically controlled to maintain 0.002 g/L dissolved oxygen, while pH was regulated at 5.0–5.5 using NaOH dosing. These conditions yielded 44.3% ethanol. A full factorial design identified Time, Air Flow Rate, Cell Loading, and Bead Mass as significant factors. RSM with Central Composite Design confirmed a significant quadratic model (F = 14.14, p < 0.0001; R² = 0.9601, Adjusted R² = 0.9201). Cell Loading (F = 48.48) and Bead Mass (F = 26.53) had the strongest effects. Optimal conditions yielded 47.9% ethanol at 52.70 h, 1.55 L/min air, 1.51 g/L cells, and 47.20 g beads, with 0.84% prediction error. Copyright © 2026 by Authors, Published by Universitas Diponegoro and BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Yacon (Smallanthus sonchifolius), a tuber rich in fructans, presents potential for application in breadmaking due to its nutritional properties and cryoprotectant activity. The aim of this study was to evaluate the incorporation of yacon flour in bread formulations (50 g/kg and 100 g/kg on flour mixture basis) and its impact on baking processes involving dough freezing. Dough consistency showed that yacon inclusion decreased the water needed to achieve a proper consistency; however, this incorporation also weakened the gluten network structure and delayed starch gelatinization. Low yacon replacement enhanced fermentation kinetics and preserved dough volume increase after the freezing process. Meanwhile, moderate yacon substitution had a negative influence on dough volume increase after freezing, a behavior attributed to a weakened gluten network. The analysis of thermal properties revealed a higher gelatinization temperature peak of starch in doughs containing yacon. Furthermore, most of the gelatinization, freezing, and thawing enthalpies were lower for doughs containing yacon due to reduced freezable water content and water-holding capacity of this flour. The bread characterization evidenced that the yacon addition darkened the bread's color, increased its hardness and reduced its springiness, while the process type mainly affects structural and dimensional attributes. In summary, the results suggest that yacon flour can be incorporated into breadmaking to provide nutritional benefits and enhance the resistance of the dough to freezing processes. However, low concentrations of yacon flour are recommended, around 50 g/kg of wheat flour substitution, to ensure that the breadmaking and final properties of the bread will not be compromised. © 2026 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

The effect of increasing levels of coconut oil (CO: 0, 100, 200, and 300 g/kg of supplement DM) on productive performance, feed intake, rumen fermentation, microbiota, and gene expression was evaluated in 24 calves (Bos indicus × Bos taurus; 180 ± 10 kg BW) on rotational grazing (Cynodon dactylon) in a completely randomized design (n = 6) for 112 days. Supplement intake (offer–refusal) and forage intake (external marker: chromium) were measured. On day 112, rumen fluid (fermentation profile, protozoa, and metagenomic analysis: 16S rRNA V3-V4) and total blood (DNA microarray: M22k) were collected. Genomic analyses were performed by comparing the control vs. the group with the best productive response. For statistical analysis, SAS PROC GLM (initial weight as a covariate), orthogonal polynomials, the Tukey test, and Spearman correlation were used, considering significant effects (p ≤ 0.05) and trend (p ≤ 0.1). The inclusion of 200 g CO/kg supplement DM showed the best average daily gain (p = 0.018; +0.139 kg/d) with the highest retained energy (p = 0.02; +0.631 Mcal/d) versus the control group. In the rumen, propionate increased (p ≤ 0.05), while protozoa decreased (p < 0.0001) and the methanogenic archaea tended to decrease (Methanobacteriaceae −44%, p = 0.08; Thermoplasmatales −35%, p = 0.06). At the transcriptional level, 19 hub genes were modulated by CO, suggesting a lower intracellular signaling (cAMP-PKA-CREB) associated with a lower stress condition and better energy metabolism regulation. In conclusion, 200 g CO/kg supplement DM is a viable strategy for improving the productive performance of livestock in tropical systems.

Harvesting insights from recent advances in yeast genomics for predictable and precision wine fermentation.

Cryospheric ecosystems in the high Arctic harbor largely unexplored microbiomes with significant biotechnological potential. The present study evaluates the biohydrogen production capabilities of the indigenous microbiome of Ny-Ålesund, Svalbard, using glacial ice and surface water samples. Dark fermentation batch assays were performed at 4°C and 20°C with 2-bromoethanesulfonate (BES), a methanogenic inhibitor, to track the succession of metabolic and taxonomic diversity. Metagenomic and functional analyses revealed that under 20°C and BES conditions, psychrotolerant microbial communities maximize biohydrogen production to 85% of the total biogas produced, with an acetate-dominant fermentation pathway, as inferred from volatile fatty acid (VFA) analysis. This evolves into a highly coordinated system utilizing a coupled Rnf-nitrogenase route alongside Formate Hydrogenlyase and [FeFe]-hydrogenase pathways. Kinetic modelling using the Modified Gompertz equation, along with Q10 temperature-sensitivity indices, demonstrated a very high latent catalytic potential in these cold-adapted microbiomes. This study indicates that Arctic microbiomes are highly elastic thermodynamically and could serve as highly efficient, manipulatable biocatalysts for the environmental recovery of bioenergy through engineered low-temperature systems.

Understanding ruminal fermentation dynamics is essential for improving feed efficiency in ruminant nutrition. This study evaluated several nonlinear regression models to describe in vitro gas production kinetics in diets with different forage-to-concentrate ratios and buffer inclusion. Fermentation experiments were conducted using total mixed rations containing various concentrate levels, both with and without dietary buffers. Cumulative gas production data were fitted to exponential, logistic, Gompertz, and Michaelis–Menten models. Model performance was assessed using statistical goodness-of-fit criteria and the biological relevance of the estimated parameters. The results showed that buffer supplementation enhanced fermentation kinetics by stabilizing pH, increasing total gas production, and modifying volatile fatty acid profiles. Although no single model consistently outperformed others, model suitability depended on the specific diet–buffer combination. Sigmoidal models generally provided better fits for buffered diets, whereas exponential models were more accurate under high-concentrate, unbuffered conditions. These findings emphasize the importance of selecting context-specific models for analyzing ruminal fermentation data. The integration of in vitro gas production and nonlinear modeling offers a reliable approach to evaluate dietary strategies that improve nutrient utilization and feed efficiency in ruminant systems.

Seaweed polysaccharides as multifunctional biotherapeutics in modulating gut microbiome, metabolic disorders and beyond: A review.

Black rice is abundant in polyphenolic antioxidants, but conventional thermal processing degrades these heat-sensitive compounds, limiting their bioactivity. Although single-strain fermentation can improve the extraction of bioactive components, it remains challenging to simultaneously balance the flavor and bioactivity of fermented black rice products. Low-temperature co-fermentation with yeast and lactobacillus has emerged as a promising strategy to enhance both the flavor profile and functional quality of fermented foods. Therefore, this study investigates the effects of low-temperature co-fermentation with Saccharomyces cerevisiae and Lactobacillus bulgaricus 134 on the quality of black rice slurry. The efficacy was systematically evaluated by monitoring fermentation kinetics, conducting polyphenol and anthocyanin metabolomics analysis, performing flavoromics analysis, and combining in vitro ABTS radical scavenging assays with a Caco-2 cell-based oxidative stress model. The results showed that this process activated β-glucosidase within the first 24 h of fermentation. By activating terpenoid and phenolic metabolic pathways, it maximized the accumulation of anthocyanins and short-chain esters during 30–36 h, which conferred the product with prominent fruity and sweet notes. Fermented black rice slurry (FBRS) exhibited potent ABTS radical scavenging activity. In the Caco-2 oxidative stress model, FBRS pretreatment restored cellular viability, upregulated the activity of endogenous antioxidant enzymes, and reduced MDA content. This study provides a theoretical foundation for developing high-nutritional, flavor-enhanced fermented black rice products.

The beneficial role of mixed-culture fermentations involving Saccharomyces cerevisiae and non-Saccharomyces yeasts in winemaking is well established. It is consistently observed that non-Saccharomyces species are rapidly outcompeted and decline in viability when co-inoculated with S. cerevisiae. However, the extent and dynamics of this phenomenon are known to be species and strain dependent. Despite these findings, only a limited number of studies have focused on mixed fermentations involving Pichia kluyveri strains. In this study, four strains of P. kluyveri and two strains of S. cerevisiae were evaluated under different fermentation conditions to investigate strain-specific interactions, viability trends and their impact on main enological metabolites. Individual population kinetics were analyzed using the Baranyi growth model. Chemical analyses revealed significant differences in acetic acid production and in ethanol and glycerol yields among wines, in a strain-dependent way. These differences could be explained by the growth dynamics of the two species during fermentation. Notably, all P. kluyveri strains exhibited a faster decline in mixed fermentations compared to pure cultures, regardless of the inoculation strategy (simultaneous or sequential). The observed reduction in viability could be partially linked to metabolites produced during fermentation.

This study investigated how three chili pepper varieties (Huanggong, millet, and long slender) affect fermentation dynamics, flavor formation, and microbial succession in spontaneously fermented chopped chili. Physicochemical analyses, sensory evaluation, GC–MS, electronic tongue analysis, and high-throughput sequencing were employed to characterize quality attributes, volatile flavor profiles, and microbial structures during the process. The results demonstrated that chili pepper variety significantly influenced fermentation behavior (pH range: 4.07–4.26; total acidity: 5.68–7.69 g/kg) and quality. Distinct differences were observed in acidification patterns, substrate utilization, sensory characteristics, and optimal fermentation stages Volatile flavor analysis revealed that chopped chili peppers produced from different varieties exhibited differentiated aroma profiles while sharing a common flavor framework composed of several key aroma-active compounds. Microbial community analysis indicated that the chili pepper variety drove distinct microbial succession patterns during the process, and dominant microbial groups showed significant correlations with the formation of specific flavor compounds. Overall, these findings demonstrate that chili pepper variety regulates flavor and quality formation in chopped chili peppers by modulating microbial community structure and metabolic activity, providing a scientific basis for raw material selection and targeted flavor control in fermented chili products. A total of 63–68 volatile compounds were identified across varieties, with OAV > 1 for 11–24 compounds. Three biological replicates were analyzed per time point.

The human diet plays a pivotal role in health, yet many studies seeking to identify health-promoting foods rely on experimental designs that poorly reflect natural circumstances. The effects of dietary fibres on the microbiota are typically examined using pooled faecal material and isolated fibres, creating unrealistic environments. Additionally, little progress has been made in distinctly characterising the fermentation rates of dietary fibres. To evaluate the temporal dynamics of gut microbial composition and metabolite production, as well as to characterise the fermentation rates of dietary fibres at an individual level, we conducted an n-of-1 longitudinal study examining responses to eight distinct dietary fibres, fermented both individually and in combination. A blend of sugarcane fibre and cassava resistant starch produced significantly higher butyrate levels (p<0.0001) than either fibre alone. Microbial profiling showed that inulin and pectin selectively enriched Bifidobacterium spp. Anaerobutyricum hallii was increased with psyllium husk, wheat dextrin, and banana resistant starch, but decreased with a mixture of sugarcane fibre and cassava resistant starch (p<0.0001). Fermentation kinetics were distinctly categorised into "fast", "medium", "slow" and "poorly-fermentable". These findings indicate that combinations of dietary fibres can be used as a strategy to engineer synergistic health-promoting metabolite responses in an individual, while establishing a standardised framework for describing fermentation rates across studies.

Enhancing the production and bioactivity of α-glucosidase-inhibitory exopolysaccharide from Bacillus amyloliquefaciens YP2 through genomics and metabolic pathway regulation.

Kombucha from Perilla frutescens is a novel fermented beverage rich in bioactive compounds. This study investigated the effects of sucrose concentration (0–20% w/v) on fermentation kinetics and the impact of storage temperature (4–6°C and 28–30°C) on bioactive retention, physicochemical properties, and microbiological stability over 28 days. Optimal fermentation was achieved at 10% sucrose, yielding the highest organic acid production (acetic acid 8.00 g/L, lactic acid 12.00 g/L) and stable antioxidant capacity (DPPH 2.41 mg AAE/mL). During storage, refrigeration at 4–6°C markedly improved retention of thermolabile compounds compared to 28–30°C: total anthocyanin content retained 5–6% higher, total polyphenols decreased only 22.9%, and DPPH radical-scavenging activity declined 24.4% (29.1% at 28–30°C). pH dropped by 12.3% under refrigeration (final 3.19). Microbial growth was strongly suppressed at 4–6°C (300-fold increase in TAMC) compared to 5,700-fold at 28–30°C. These findings demonstrate that 10% sucrose combined with cold storage (4–6°C) optimally preserves bioactive compounds, physicochemical stability, and microbiological safety, providing a scientific basis for commercial production of functional perilla kombucha.

Influence of Caatinga honey floral origin on fermentation performance, chemical composition, and bioactive profile of mead.

Strategic ultrasonic regulation of Saccharomyces cerevisiae fermentation for enhanced anthocyanin production and wine quality.

The demand for protein crops to feed livestock is increasing, with soybean meal (SBM) and rapeseed meal (RSM) currently being two of the major protein sources. However, using land to grow protein crops for livestock competes with crops which can be consumed directly by humans. At the same time, there are increasing concerns about the environmental impact of growing some crops, especially soybean, due to the land-use change which is associated with it's growth in some countries. Thus, there is a need to identify alternative protein sources for livestock, with microalgae being one potential source. However, it is important to understand the impact of microalgae species and inclusion level on rumen fermentation and methane production. This study examined the effects of substituting SBM and RSM (replacing 5, 10 and 20% of SBM and RSM) with three different microalgae species ( Spirulina Platensis [SP], Chlorella Vulgaris [CLV] and Nannochloropsis Gaditana [NG]) on in vitro methane (CH 4 ) production and rumen fermentation characteristics. Samples were incubated for 4, 24 and 48-h with grass silage (GS) as the basal substrate in in vitro batch culture to mimic the rumen. While volatile fatty acid concentrations in the fermentation liquor and CH 4 concentrations did not differ between microalgae inclusion levels, CLV at 10 and 20% inclusions increased propionate concentration by 8.3% and 5.8%, respectively and decreased CH 4 concentration by 12.3% and 26.9%, respectively, compared with 0% inclusion. Ammonia-nitrogen (NH 3 -N) concentrations were comparable across microalgae inclusion levels, except for the 20% inclusion where NH 3 -N increased (within SP) and decreased (within CLV). The measured parameters demonstrated substrate-specific responses to microalgae species. For instance, SBM incubated with SP and CLV reduced CH 4 concentration by 23.5% and 18.5%, respectively, but increased propionate concentration by 8.8% and 12.1%, respectively. Similarly, RSM incubated with NG showed 26.3% lower CH 4 concentration and 14.3% higher propionate concentration relative to SBM at 24-h, indicating significant interactions between substrates and the microalgae species. This in vitro study highlights the importance of selecting suitable microalgae species, inclusion levels and substrates when examining the potential of microalgae as a protein replacement. In conclusion, SP, CLV and NG had no adverse effects on in vitro fermentation parameters suggesting that they may have potential as alternative protein sources, while CLV in particular demonstrated potential methane-mitigating effects. • Microalgae inclusions had no detrimental effects on in vitro rumen fermentation parameters. • The inclusion of CLV at 10 and 20% increased propionate levels and reduced CH 4 emissions. • The tested microalgae species exhibited substrate specific response for all in vitro fermentation parameters.

Metabolomic profiling of sweet potato snacks enriched with agave fructans: Effects of vacuum impregnation on in vitro gut-associated metabolites.