Hasil untuk "Fermentation industries. Beverages. Alcohol"

Isabele Paola de Oliveira Amaral, Mariany Felex de Oliveira, Marco Antonio Previdelli Orrico Junior et al.

This study evaluated the effects of lasalocid sodium (LASA) and essential oils on the fermentation and nutritional quality of total mixed ration (TMR) silages. A 4 × 2 factorial design tested four additives—a control (distilled water), LASA (375 mg/kg DM), limonene essential oil (LEO), and a blend of cinnamaldehyde and carvacrol (EOB), both at 400 mg/kg DM—during summer and autumn. The TMRs were formulated to meet the nutritional requirements of lactating cows producing 20 kg of milk per day. After 110 days of ensiling, silages were analyzed for fermentation losses, pH, short-chain fatty acids, ammoniacal nitrogen (NH₃-N), aerobic stability (AS), and chemical composition. The additives significantly improved dry matter recovery (DMR), especially LASA and EOB in autumn. EOB showed the lowest effluent losses and highest AS, with higher acetic acid and lower NH₃-N contents. LEO and EOB increased lactic acid, while LASA reduced ethanol and butyric acid levels in summer. Crude protein increased with LEO in autumn, and LASA and LEO improved total digestible nutrients (TDNs) in summer. EOB-treated silages had higher fiber fractions in autumn, without compromising feed value. Therefore, LASA, LEO, and particularly EOB enhanced silage fermentation and nutrient preservation, with EOB showing the most consistent results across seasons.

Stefan W. Ritter, Quentin P. Thiel, Martina I. Gastl et al.

Abstract Background The market for beverages is highly changing within the last years. Increasing consumer awareness towards healthier drinks led to the revival of traditional and the creation of innovative beverages. Various protein-rich legumes were used for milk analogues, which might be also valuable raw materials for refreshing, protein-rich beverages. However, no such applications have been marketed so far, which might be due to unpleasant organoleptic impressions like the legume-typical “beany” aroma. Lactic acid fermentation has already been proven to be a remedy to overcome this hindrance in consumer acceptance. Results In this study, a statistically based approach was used to elucidate the impact of the fermentation parameters temperature, inoculum cell concentration, and methionine addition on the fermentation of lupine- and faba bean-based substrates. A total of 39 models were found and verified. The majority of these models indicate a strong impact of the temperature on the reduction of aldehydes connected to the “beany” impression (e.g., hexanal) and on the production of pleasantly perceived aroma compounds (e.g., β-damascenone). Positively, the addition of methionine had only minor impacts on the negatively associated sulfuric compounds methional, dimethyl sulfide, dimethyl disulfide, and dimethyl trisulfide. Moreover, in further fermentations, the time was added as an additional parameter. It was shown that the strains grew well, strongly acidified the both substrates (pH ≤ 4.0) within 6.5 h, and reached cell counts of > 9 log10 CFU/mL after 24 h. Notably, most of the aldehydes (like hexanal) were reduced within the first 6–7 h, whereas pleasant compounds like β-damascenone reached high concentrations especially in the later fermentation (approx. 24–48 h). Conclusions Out of the fermentation parameters temperature, inoculum cell concentration, and methionine addition, the temperature had the highest influence on the observed aroma and taste active compounds. As the addition of methionine to compensate for the legume-typical deficit did not lead to an adverse effect, fortifying legume-based substrates with methionine should be considered to improve the bioavailability of the legume protein. Aldehydes, which are associated with the “beany” aroma impression, can be removed efficiently in fermentation. However, terminating the process prematurely would lead to an incomplete production of pleasant aroma compounds.

Qing Dou, Bin Luo, Xinghong Dai et al.

In the enhancement of Novel <i>Sorghum bicolor</i> × <i>S. propinquum</i> Hybrid utilization, optimal planting densities and silage methods remain elusive. This study assesses the effects of planting densities, cellulase (CE), <i>Lactobacillus buchneri</i> (LAB), and their combination (LC) on fermentation quality and bacterial diversity of the hybrid silage. The experiment was carried out in a completely random block design with four additives and five planting densities (M1, M2, M3, M4, M5) as follows (4 additives × 5 planting densities): a control group without additives (CK), a group treated with <i>Lactobacillus buchneri</i> (LAB), a group with cellulase (CE), and a group treated with a combination of LAB and CE (LC), maintaining triplicates per treatment. In this study, the additive treatment improved the fermentation quality of silage compared with the control. In the M2-LC group, the contents of crude protein (CP; 7.88%), ether extract (EE; 1.91%), and ash (7.76%) were the highest, while the pH (3.30) was the lowest. The water-soluble carbohydrate (WSC; 11.28%) content was the highest in the M3-CE group, the lactic acid (LA; 6.79%) content was the highest in the M4-CE group, and the acetic acid (AA; 7.71%) content was the highest in the M2-LAB group. Meanwhile, the neutral washing fiber (NDF; 53.17%) content was the lowest in the M5-CE group, the acid detergent fiber (ADF; 41.01%) content was the lowest in the M2-CE group, and the propionic acid (PA; 0.26%) content was the lowest in the M1-LAB group. Adding LC notably reduced bacterial diversity, boosted <i>Lentilactobacillus</i>, and curbed Proteobacteria. LAB and LC markedly improved amino acid metabolism over CE and CK. Conversely, beta-lactam resistance, flagellar assembly, and ascorbate/aldarate metabolism pathways were suppressed. In the future, we will explore a variety of additives and adjust the cutting height to improve its comprehensive quality, create an innovative path for silage production, promote the efficient use of agricultural resources, and provide high-quality feed for animal husbandry.

Syed Shaheer Hassan, Jinyan Zhao, Sana Tahir et al.

This study enhanced germanium (Ge) enrichment in the liquid fermentation of the edible fungus <i>Lyophyllum decastes</i> in order to boost its biological activity, particularly its antioxidant and immunomodulatory properties. Through the use of single-factor and Plackett–Burman designs, the experiments revealed critical parameters affecting Ge enrichment, including Ge oxide concentration, potato powder concentration, and peptone levels. The optimization of the Box–Behnken response surface methodology resulted in a Ge concentration of 3.61 mg/L, significantly enhancing the biomass, protein, polysaccharide, and flavonoid content in the mycelium. In contrast to traditional fermentation, Ge-rich fermentation enhanced the mycelial biomass by 30.97% and elevated the organic Ge content 50.19-fold. An analysis of the antioxidants revealed that the Ge-enriched mycelial water extract exhibited heightened activity, augmenting TNF-α production in RAW264.7 cells by 73.29% at a concentration of 200 μg/g. These findings indicate that the Ge-enriched fermentation of <i>L. decastes</i> holds promise for functional applications in health-supportive products due to its robust antioxidant and immune-enhancing capabilities.

Ahmed E. Kholif

The experiment aimed to evaluate the effects of varying levels of <i>Laurus nobilis</i> leaves [0% (control), 0.5%, 1%, 1.5%, and 2%] on the in vitro ruminal fermentation of a ruminant diet consisting of a 50% concentrate mixture, 40% berseem hay (<i>Trifolium alexandrinum</i>), and 10% rice straw (<i>Oryza sativa</i>). The in vitro incubation lasted 48 h, during which gas production (GP), methane (CH₄), carbon dioxide (CO₂), total and individual short-chain fatty acids (SCFA), and nutrient degradability were measured. The experiment utilized a randomized block design and consisted of two incubation runs. Gas chromatography analysis revealed that 1,8-cineole (81%) was the primary volatile compound in the <i>L. nobilis</i> leaves. The 0.5% inclusion level exhibited the highest (linear, <i>p</i> = 0.006) asymptotic GP and lowest lag of GP (linear, <i>p</i> = 0.002), while the 2% inclusion level had the highest lag of GP. The 2% inclusion level significantly lowered CH₄ (linear, <i>p</i> = 0.003) compared to the control, and all levels of the leaves linearly decreased in the proportional CH₄ production (<i>p</i> = 0.001), with the lowest value at the 0.5% inclusion level. The highest asymptotic CO₂ production was observed with the 0.5% inclusion level (linear, <i>p</i> = 0.002), while the 0.5%, 1%, and 1.5% inclusion levels significantly increased (quadratic, <i>p</i> = 0.006) the proportion of CO₂ compared to the control. The 0.5% inclusion level showed the highest (<i>p</i> < 0.001) degradable DM and fiber fractions compared to the control, whereas the 2% level decreased them. The 0.5% inclusion level resulted in the highest (<i>p</i> < 0.01) production of total SCFA, acetate, and propionate. Additionally, the 0.5% inclusion level demonstrated the highest (<i>p</i> < 0.05) metabolizable energy and microbial crude protein, while the 2% level reduced these measures compared to the control. It is concluded that <i>L. nobilis</i> leaves can be included at 0.5% of the ruminant diet (e.g., sheep) to improve ruminal fermentation and reduce CH₄ production.

Floriana Boscaino, Elena Ionata, Salvatore De Caro et al.

Non-conventional yeasts (NCYs) (i.e., non-<i>Saccharomyces</i>) are used as alternative starters to promote aroma complexity of fermented foods (e.g., bakery products). A total of 66 yeasts isolated from artisanal food matrices (bread and pizza sourdoughs and milk whey) from different geographical areas of the Campania region (Italy) were screened for physiological and technological characteristics such as leavening ability, resistance to NaCl and pH, exopolysaccharide and phytase activity production, and carbohydrate assimilation. Selected and isolated microorganisms were also used to study the leavening kinetics in experimental doughs as mixed inocula of two different strains. Volatile organic compounds (VOCs) of the inoculated doughs were analyzed with solid-phase microextraction/gas chromatography–mass spectrometry (SPME/GC-MS). Most of the strains belonged to non-<i>Saccharomyces</i> species (<i>Pichia kudriavzevii</i>, <i>Kluyveromyces marxianus</i>) and <i>Saccharomyces</i> (<i>S. cerevisiae</i>). Several strains produced exopolysaccharides (EPSs), that are important for dough rheological properties. Moreover, yeasts isolated from whey showed extracellular phytase activity. The mixed starter culture of the <i>S. cerevisiae</i> and NCY strains showed a synergic effect that enhanced the doughs’ aroma complexity. The use of non-conventional yeasts mixed with <i>S. cerevisiae</i> strains can be advantageous in the bakery industry because they improve the bread aroma profiles and nutritional properties by bioactive molecule production.

Mingjing Yao, Chunmin Ma, Xin Bian et al.

Cardiovascular disease (CVD) has become the leading cause of death, and it is critical to develop new functional foods to prevent intravascular thrombosis, the key cause of CVD. Fermented soy-based food is a good choice because of its native fibrinolytic enzyme (FE) activity. In this study, a strain that can produce a new type of fibrinolytic enzyme was selected from Chinese Douchi and identified as <i>Bacillus licheniformis</i> SFD-Y5 by molecular biology experiments and physiological and biochemical experiments. Single factor experiments combined with statistical experiments, including Plackett–Burman experiment, steepest ascent experiment and RSM (Box–Behnken design), were used to optimize the fermentation of FE by <i>B. licheniformis</i> SFD-Y5. The final FE activity was 2434.45 ± 28.49 IU/mL under optimal conditions, which is the highest FE activity produced by wild <i>B. licheniformis</i> so far. Further studies showed that Y5 FE is a serine metalloproteinase with good stability at alkaline pHs (pH 8.0–11.0). The results of our study could lay a foundation for the future production, molecular modification and further application in functional foods of Y5 FE.

Min-Jin Lim, Kaliyan Barathikannan, Ye-Jin Jeong et al.

The escalating global incidence of obesity and chronic diet-related disorders, such as type 2 diabetes, hypertension, cardiovascular disease, malignancies, and celiac disease, has intensified the focus on dietary factors and disease risks. Rice, a dietary staple for billions, is under scrutiny, particularly polished or white rice, which is high in starch and in the glycemic index and low in nutrition due to the removal of the outer bran layer during milling. This study critically analyzes the comparison between whole brown rice (BR) and milled white rice in terms of health benefits. A significant finding is the enhancement of food nutrition through fermentation, which improves protein digestibility and mineral availability and releases peptides and amino acids. The study also highlights the increased antibacterial and antioxidant activity of foods, including health benefits, through fermentation. A comprehensive review of existing data on the nutritional content and health advantages of whole fermented BR grains is presented, alongside experiments in developing fermented BR-based foods. The safety, preservation, and the economic and environmental advantages of consuming regularly fermented BR instead of white or unfermented BR are discussed. Finally, the paper addresses the commercialization challenges and future opportunities for promoting fermented BR as a healthier food alternative.

Jian Wu, Meiru Jiang, Shutian Kong et al.

5-Aminolevulinic acid (5-ALA) has recently received much attention for its wide applications in medicine and agriculture. In this study, we investigated the effect of <i>NCgl0580</i> in <i>Corynebacterium glutamicum</i> on 5-ALA biosynthesis as well as its possible mechanism. It was found that the overexpression of <i>NCgl0580</i> increased 5-ALA production by approximately 53.3%. Interestingly, the knockout of this gene led to an even more significant 2.49-fold increase in 5-ALA production. According to transcriptome analysis and functional validation of phenotype-related targets, the deletion of <i>NCgl0580</i> brought about considerable changes in the transcript levels of genes involved in central carbon metabolism, leading to fluxes redistribution toward the 5-ALA precursor succinyl-CoA as well as ATP-binding cassette (ABC) transporters affecting 5-ALA biosynthesis. In particular, the positive effects of enhanced sugar transport (by overexpressing <i>NCgl1445</i> and <i>iolT1</i>), glycolysis (by overexpressing <i>pyk2</i>), iron uptake (by overexpressing <i>afuABC</i>), and phosphate uptake (by overexpressing <i>pstSCAB</i> and <i>ugpQ</i>) on 5-ALA biosynthesis were demonstrated for the first time. Thus, the transcriptional mechanism underlying the effect of <i>NCgl0580</i> deletion on 5-ALA biosynthesis was elucidated, providing new strategies to regulate the metabolic network of <i>C. glutamicum</i> to achieve a further increase in 5-ALA production.

Sanjib Kumar Karmee

Waste valorization is an important strategy to reduce environmental pollution and dependency on petroleum-based fuels. In this regard, utilization of food waste as a versatile and low-cost resource is important. Several advanced catalytic methods for the valorization of food waste have been widely investigated for the production of liquid biofuels. Along this line, chemical catalysts have been explored for the synthesis of liquid biofuels. Chemo-catalysis is mainly metal based, which requires harsh process conditions. Alternatively, biocatalysts are currently being investigated as a result of several advantages such as mild reaction conditions, recyclability, selectivity and biodegradability. In this work, recent biocatalytic technologies for the preparation of liquid biofuels through food waste valorization are discussed thoroughly. Lipases are employed for the synthesis of biodiesel and the upgradation of bio-oil, whereas methane mono-oxygenases could be explored for the production of methanol via the oxidation of methane generated from food wastes. Industrial production of ethanol from food waste using bioconversion technologies is a success story. To date, there has been no specific report on the use of food waste for propanol preparation using enzymes. The ABE process (Acetone–Butanol–Ethanol) (using suitable microorganisms) is used for butanol preparation, where the vacuum stripping system is integrated to remove butanol from the broth and circumvent inhibition. The synthesis of hydrocarbon fuels from fatty acids and triglycerides can be carried out using enzymes, such as carboxylic acid reductase and fatty acid photodecarboxylase (an algal photoenzyme). Both carboxylic acid reductase and fatty acid photodecarboxylase have not yet been applied in the direct valorization of food wastes. Furthermore, limitations of the reported methods, societal and economic aspects and a fresh perspective on the subject, along with important examples, are described.

John Samelis, Charikleia Tsanasidou, Loulouda Bosnea et al.

The performance of a mixed thermophilic and mesophilic starter culture consisting of <i>Streptococcus thermophilus</i> ST1 and the Greek indigenous nisin-A-producing <i>Lactococcus lactis</i> subsp. <i>cremoris</i> M78 was evaluated in the absence (A: ST1+M78) or presence (B: ST1+M78+H25) of <i>Lactiplantibacillus plantarum</i> H25—another indigenous ripening strain—under real cheesemaking conditions. Three pilot-scale trials of fresh (6-day-old) Galotyri PDO cheese were made from boiled milk by an artisanal method using simple equipment, followed by cold ripening of the A1–A3 and B1–B3 cheeses at 4 °C for 30 days. All of the cheeses were analyzed microbiologically and for pH, gross composition, proteolysis, sugar and organic acid contents, and sensorial attributes before and after ripening. The artisanal (PDO) Galotyri manufacturing method did not ensure optimal growth of the ST1+M78 starter as regards the constant ability of the thermophilic strain ST1 to act as the primary milk acidifier under ambient (20–30 °C) fermentation conditions. Consequently, major trial-dependent microbial and biochemical differences between the Acheeses, and generally extended to the Bcheeses, were found. However, high-quality Galotyri was produced when either starter strain predominated in the fresh cheeses; only trial A1 had microbiological and sensory defects due to an outgrowth of post-thermal Gram-negative bacterial contaminants in the acidified curd. The H25 adjunct strain, which grew above 7 to 9 log CFU/g depending on the trial, had minor effects on the cheese’s pH, gross composition, and proteolysis, but it improved the texture, flavor, and the bacteriological quality of the Bcheeses during processing, and it exerted antifungal effects in the ripened cheeses.

Frederik Nikolai Schulz, Barbara Richter, Jon H. Hanf

In February 2022, the European Parliament agreed on a far-reaching package of measures to regulate alcohol consumption in its vote on “Strengthening Europe in the fight against cancer”. This article therefore elaborates on the most important positions and directions of current European alcohol policy and discusses possible effects on the German wine industry based on existing literature. It can be shown that the attitudes towards alcohol consumption sometimes differ considerably within the European Union, but that there is increasing harmonization of consumption-regulating measures in the course of European integration. However, alcohol policies in the EU are limited by an unclear scientific assessment of “moderate” consumption. This is supplemented by moderate social awareness and the scientific discourse on the effectiveness of alcohol policy measures, as well as a lack of government initiative and legal barriers. Ultimately, the German wine industry finds itself confronted with new scientific findings, associated political demands and creeping changes in social attitudes towards alcoholic beverages.

Qiuyun Tian, Brittany Whiting, Bernard Chen

Wineinformatics is among the new fields in data science that use wine as domain knowledge. To process large amounts of wine review data in human language format, the computational wine wheel is applied. In previous research, the computational wine wheel was created and applied to different datasets of wine reviews developed by Wine Spectator. The goal of this research is to explore the development and application of the computational wine wheel to reviews from a different reviewer, Robert Parker. For comparison, this research collects 513 elite Bordeaux wines that were reviewed by both Robert Parker and Wine Spectator. The full power of the computational wine wheel is utilized, including NORMALIZED, CATEGORY, and SUBCATEGORY attributes. The datasets are then used to predict whether the wine is a classic wine (95 + scores) or not (94 − scores) using the black-box classification algorithm support vector machine. The Wine Spectator’s dataset, with a combination of NORMALIZED, CATEGORY, and SUBCATEGORY attributes, achieves the best accuracy of 76.02%. Robert Parker’s dataset also achieves an accuracy of 75.63% out of all the attribute combinations, which demonstrates the usefulness of the computational wine wheel and that it can be effectively adopted in different wine reviewers’ systems. This paper also attempts to build a classification model using both Robert Parker’s and Wine Spectator’s reviews, resulting in comparable prediction power.

Martina Brožová, Dagmar Matoulková, Alexandr Mikyška et al.

Although barley malt is considered a traditional appropriate raw material for beer production, there are several reasons to introduce alternative sugar or starchy materials into brewing. Economic and market demands play a crucial role in the selection of raw materials. However, different adjuncts bring various technological challenges due to their specific physicochemical properties as well as the degree of processing when entering to the brewery. This review is focused on the current practice as well as on innovations in the use of several barley malt substitutes. The beer production from various proportions of adjuncts is presented step by step and the pros and cons associated with technological changes and equipment are discussed. The impact on sensory character is also considered. The aim of the paper is to offer theoretical background and reveal the latest possibilities for practice.

Van Hong Thi Pham, Jaisoo Kim, Soonwoong Chang et al.

The emission of methylene blue (MB) from common industries causes risks to human health by making clean drinking water unavailable and hampering environmental safety. A biological approach offering a more cost-efficient and sustainable alternative solution has been studied and demonstrated to be significantly effective for the removal of MB using promising microbial isolates. Therefore, this study targeted bacterial candidates, namely <i>Bacillus</i> sp. React3, isolated from soil with the potential to decolorize MB. The phenogenic identification of strain React3 was performed by 16S rRNA sequencing, showing a similarity of 98.86% to <i>Bacillus velezensis</i> CR-502T. The ability of this bacterial strain to decolorize MB was proven through both the lignin peroxidase efficiency and accumulation in the biomass of the living cells. MB removal was determined by the reduction in the maximum absorption at a wavelength of 665 nm, which was observed to be up to 99.5% after 48 h of incubation. The optimal conditions for the MB degradation of strain React3 were pH 7, 35 °C, static, 4% inoculum, and 1000 mg/L of MB, with tryptone as a carbon source and yeast extract as a nitrogen source.

Yao Sun, Shiyu Liu, Zhe Zhan et al.

<i>Pseudomonas fluorescens (P. fluorescens)</i> and <i>Pseudomonas fragi (P. fragi)</i>, two kinds of psychrotrophic <i>Pseudomonas</i> species with pathogenicity, are likely to contaminate foods and cause diseases even in fairly cold environments, an outcome which should be suppressed. This paper investigates the antibacterial mechanisms of <i>Dellaglioa algida (D. algida)</i>, a new type of low-temperature-resistant <i>Lactobacillus</i>, on two such <i>Pseudomonas</i>. By the enzyme treatment approach, the antibacterial substance existing in the cell-free supernatant (CFS) of <i>D. algida</i> is preliminarily determined as organic acid or protein; then, its inhibition effects are assessed under various culture environments, including pH value, salinity, and culture time, where the best antibacterial performance is achieved at pH = 6.00, S = 0%, and culture time = 48 h. A series of experiments on biofilms indicate that <i>D. algida</i> is not only able to inhibit the generation or damage the integrality of the biofilm of the two mentioned <i>Pseudomonas</i>, but also can reduce the motility, including swarming and swimming, of <i>P. fragi</i> and restrain the swarming of <i>P. fluorescens</i>. The aformentioned developed antibacterial mechanisms show the possibility of using <i>D. algida</i> in applications as an inhibitor for psychrotrophic <i>Pseudomonas</i> in the food industry, by virtue of its strong suppression capability, especially in cold environments.

Mariana Muniz da Silva, Angélica Cristina de Souza, Emanuel Roberto Faria et al.

Kombucha is a beverage obtained from fermentation of <i>Camellia sinensis</i> tea using a symbiotic culture of bacteria and yeast (SCOBY). This association of bacteria and yeasts can be an interesting source of microorganisms for developing fermented beverages, including beer. The objective of this study was to evaluate kombucha SCOBY and commercial brewing yeast as a starter culture for the elaboration of beer. Three assays were performed to develop the beverage (C = control, KL = kombucha + yeast, K = kombucha). The pH, density, carbohydrates, organic acids and ethanol were evaluated during fermentation. Microbial counts (yeasts and mesophilic bacteria) and volatile compounds were recorded at the initial and final fermentation times. The content of total phenolic compounds, antioxidant capacity, color and bitterness (IBU) of the beers were determined. The results showed that kombucha-fermented wort produces a beer with differentiated characteristics. Increased lactic acid (0.73 g/L) and low alcohol content (1.3%) were observed in the K assay. Further, desired volatile compounds, such as ethyl octanoate, phenethyl acetate and 2-phenylethanol, were also found in this beer. The combination of kombucha and commercial yeast for beer production showed carbohydrate consumption and contents of organic acids similar to those of control beer, producing beers with an alcohol content of 5.9%. From the results, it was possible to observe a tendency for the content of total phenolic compounds (37.57, 33.00 and 31.64 mg/100 mL for K, KY and C assays, respectively) to increase when the wort was inoculated with kombucha. There was no difference in the antioxidant activity of the produced beers. All produced beers showed a yellowish color and a bitterness value (IBU) of 27%. The present study showed that adding kombucha as a starter culture produced beer with differentiated properties, such as high antioxidant activity, low alcohol content and sour characteristics.

Antonella Costantini, Maria Carla Cravero, Loretta Panero et al.

The role of yeast in wine quality is very important. The use of selected autochthonous yeasts is becoming more and more frequent in enology, not only to obtain a diversification of wines, but also as a link between the wine and its territory of origin. The objectives of this work were to test two indigenous yeasts in a cellar on a pilot scale. The yeasts were a strain of Saccharomyces cerevisiae and a strain of Saccharomyces paradoxus previously isolated in a vineyard in Piedmont (Italy). Studying the oenological characteristics of S. paradoxus is of particular interest, as it is rarely found in the cellar–vineyard environment. Molecular biology methods confirmed the predominance of the strain inoculated in the various fermentation tests. Additionally, products of yeast metabolism, including volatile compounds, were quantified at the end of the alcoholic fermentation and sensory profile of wines was tested by a trained panel of tasters. Our results indicated that both strains have good characteristics to be used as starter in winemaking; S. paradoxus was characterized by a high production of glycerol and the ability to degrade malic acid, together with a lower production of ethanol and a low volatile acidity, while S. cerevisiae conferred to the wine a pleasant smell of rose, as highlighted in the sessions of sensory analysis.

Lu Wang, Xu Yang, Zhuoting Li et al.

In this work, the hydrothermal extract of spent coffee grounds (SCG) was used to make alcoholic beverages with commercial <i>S. cerevisiae</i> strain D254. The sensory characteristics of the SCG alcoholic beverages were analyzed using sensory description, electronic nose, electronic tongue, and gas chromatography-mass spectrometry (GC-MS). The results suggested that the supplement of 0.20% (NH₄)₂HPO₄ was effective at improving growth and alcohol fermentation of <i>Saccharomyces cerevisiae</i> D254 in SCG extract. SCG fermented beverages (SFB) and SCG distilled spirits (SDS) produced at the optimized fermentation conditions had appropriate physicochemical properties and different sensory characteristics. Fermentation aromas, especially esters, were produced in SFB, increasing the complexity of aroma and lowing the irritating aroma. The combination of original and fermentation components might balance the outstanding sourness, astringency, and saltiness tastes of SFB. The fermentation aroma was partially lost and the sourness, bitterness, astringency, and saltiness tastes were relieved in distillation, leading to the relatively more prominent aroma typicality of coffee and a soft taste. These findings lay a foundation for producing new high-quality coffee-flavored alcoholic beverages or flavoring liquors.

Natalia S. Brizuela, Marina Arnez-Arancibia, Liliana Semorile et al.

<i>Lactiplantibacillus plantarum</i> strain UNQLp 11 is a lactic acid bacterium with the potential to carry out malolactic fermentation (MLF) in red wines. Recently, the complete genome of UNQLp 11 was sequenced and this strain possesses four loci of the enzyme β-glucosidase. In order to demonstrate that these glucosidase enzymes could be functional under harsh wine conditions, we evaluated the hydrolysis of p-nitrophenyl-β-D-glucopyranoside (p-NPG) in synthetic wine with different ethanol contents (0%, 12%, and 14% <i>v/v</i>) and at different pH values (3.2, 3.5, and 3.8). Then, the hydrolysis of precursor n-octyl β-D-glucopyranoside was analyzed in sterile Pinot Noir wine (containing 14.5% <i>v/v</i> of ethanol, at different pH values) by headspace sorptive extraction gas chromatography-mass spectrometry (HSSE-GC/MS). The hydrolysis of p-NPG showed that β-glucosidase activity is very susceptible to low pH but induced in the presence of high ethanol content. Furthermore, UNQLp 11 was able to release the glycosilated precursor n-octyl, during MLF to a greater extent than a commercial enzyme. In conclusion, UNQLp 11 could improve the aromatic profile of the wine by the release of volatile precursors during MLF.