A review of methods of low alcohol and alcohol-free beer production

Application of Non-Saccharomyces Yeast for the Production of Low-Alcohol Beer

In recent years, demand for low-alcohol and alcohol-free beers has been rising. Of the many methods of producing such beers, many have expensive implementation requirements or drawbacks in terms of beer quality. The exploration of non-Saccharomyces yeast species presents a promising opportunity to overcome these challenges. These yeasts, with their diverse metabolic capabilities and unique flavor profiles, offer the potential to create innovative and flavorful low-alcohol beers. The study investigates the feasibility of using selected non-Saccharomyces yeasts for brewing low-alcohol beers, focusing on fermentation kinetics, physicochemical parameters, and the sensory attributes of the final product. The evaluated yeast species were Kluyveromyces lactis MG971263, Metschnikowia pulcherrima MG971247 and MG971250, Torulaspora delbrueckii MG971248, Wickerhamomyces anomalus MG971261, and W. onychis MG971246. Two strains of Saccharomyces cerevisiae were used as a control. The results of the study show that selected non-Saccharomyces yeast species might be used to produce low-alcohol beers. The non-Saccharomyces yeast allowed the researchers to obtain beers with an alcohol content in the range of 0.5-1.05%, while the control beer brewed with US-05 had an alcohol content of 3.77%. Among the evaluated strains, the strains M. pulcherrima MG971250 and T. delbrueckii MG971248 were found to be rated better in a sensory evaluation than the brewed and low-alcohol strains of S. cerevisiae.

Cold extraction process for producing a low-alcohol beer, International Pale Lager style: Evaluation and description of flavors using electronic tongue

Grains germinate, dry, and then undergo crushing before being combined with hot water to yield a sweet and viscous liquid known as wort. To enhance flavor and aroma compounds while maintaining a lower alcohol content, cold water is utilized during wort production without increasing its density. Recent years have witnessed a surge in demand for beverages with reduced alcohol content, reflecting shifting consumer preferences towards healthier lifestyles. Notably, consumers of low-alcohol beers seek products that closely mimic traditional beers. In response, batches of low-alcohol beer were meticulously crafted using a cold extraction method with room temperature water, resulting in a beer with 1.11% alcohol by volume (ABV). Sensory evaluations yielded a favorable score of 27 out of 50, indicating adherence to style standards and absence of major technical flaws. Furthermore, electronic taste profiling revealed a striking similarity between the low-alcohol beer and the benchmark International Pale Lager style, exemplified by commercial beers (5 and 0.03% ABV). Notably, the reduced-alcohol variant boasted lower caloric content compared to both standard and non-alcoholic counterparts. Consequently, the cold extraction approach emerges as a promising technique for producing low-alcohol beers within the International Pale Lager style, catering to evolving consumer preferences and health-conscious trends.

The two faces of microorganisms in traditional brewing and the implications for no- and low-alcohol beers

The production of alcoholic beverages is intrinsically linked to microbial activity. This is because microbes such as yeast are associated with the production of ethanol and key sensorial compounds that produce desirable qualities in fermented products. However, the brewing industry and other related sectors face a step-change in practice, primarily due to the growth in sales of no- and low-alcohol (NoLo) alternatives to traditional alcoholic products. Here we review the involvement of microbes across the brewing process, including both their positive contributions and their negative (spoilage) effects. We also discuss the opportunities for exploiting microbes for NoLo beer production, as well as the spoilage risks associated with these products. For the latter, we highlight differences in composition and process conditions between traditional and NoLo beers and discuss how these may impact the microbial ecosystem of each product stream in relation to microbiological stability and final beer quality.

Effect of Coriander Seed Addition at Different Stages of Brewing on Selected Parameters of Low-Alcohol Wheat Beers

In recent years, there has been a significant decline in interest in high-alcohol beers, while interest in low- and non-alcohol beers is growing. The aim of this study was to investigate the influence of the addition of coriander seeds at various stages of the production of low-alcohol wheat beer (mashing, boiling, and fermentation). The presented article uses biological methods to produce low-alcohol beer. For this purpose, first, the mashing process was modified (breaking 44 °C for 20 min, followed by 75 °C for 60 min). The chemical composition and aroma components of the obtained beers were determined using various chromatographic methods (HPLC, GC-MS, and GC-O). Differences were found between the aroma components depending on the stage of production at which the coriander seeds were added. Beers with the addition of coriander seeds at the fermentation stage had the highest terpene content (linalool, camphor, trans-linalool oxide, and γ-terpinene) and boiling (myrcene, limonene, citronellol, and geraniol). The least desirable process is the addition of coriander seeds at the mashing stage due to the lowest content of volatile compounds. Additionally, beers with the addition of coriander seeds for fermentation were characterized by a higher content of antioxidant compounds. This proves that the addition of coriander seeds during beer production could improve the fermentation process and modify the quality of the obtaining beer.

Recycled Brewer's Spent Grain (BSG) and Grape Juice: A New Tool for Non-Alcoholic (NAB) or Low-Alcoholic (LAB) Craft Beer Using Non-Conventional Yeasts

Non-alcoholic beer (NAB) and low-alcoholic beer (LAB) are taking over the market with growing sales. Sustainable recycling and valorization of exhausted brewer's spent grain (BSG) coming from craft beer is a relevant issue in the brewing process. In this work, recycled BSG and BSG + GJ (supplemented with 10% grape juice) were used as a wort substrate to inoculate Lachancea thermotolerans, Wickeramhomyces anomalus, Torulaspora delbruecki and Pichia kluyveri non-conventional yeasts to produce NABLAB craft beer. Results showed that wort composed of only recycled BSG produced appreciated NAB beers (ethanol concentration from 0.12% to 0.54% v/v), while the addition of 10% grape juice produced LAB beers (ethanol concentration from 0.82 to 1.66% v/v). As expected, volatile compound production was highest with the addition of grape juice. L. thermotolerans showed lactic acid production, characterizing both worts with the production of ethyl butyrate and isoamyl acetate. T. delbrueckii exhibited relevant amounts of hexanol, phenyl ethyl acetate and β-phenyl ethanol (BSG + GJ). W. anomalus and P. kluyveri showed consistent volatile production, but only in BSG + GJ where fermentation activity was exhibited. The overall results indicated that reused BSGs, non-conventional yeasts and grape juice are suitable bioprocesses for specialty NABLAB beer.

Enhancing satiety and aerobic performance with beer microparticles-based non-alcoholic drinks: exploring dose and duration effects

Beer is an alcoholic beverage, rich in carbohydrates, amino acids, vitamins and polyphenols, consumed worldwide as a social drink. There is a large number of beer styles which depends on the ingredients and brewing process. The consumption of beer as a fluid replacement after sport practice is a current discussion in literature. A non-alcoholic pale-ale microparticles-based beverage (PABM) have been previously designed, however, its phenolic profile and ergogenic effect remain unknown. Thus, this study aims to verify the ergogenic potential (increase of running performance) of PAMB in male Wistar rats. Beer microparticles were obtained by spray drying and beverages with different concentrations were prepared in water. Wistar rats were subjected to a training protocol on a treadmill (5 times/week, 60 min/day) and daily intake of PABM (20 mg.kg-1 or 200 mg.kg-1) or water by gavage. Chlorogenic acid was found to be the main component in the phenolic profile (12.28 mg·g-1) of PABM analyzed with high-performance liquid chromatography and mass spectrometry. An increase in the aerobic performance was observed after 4 weeks in the 20 mg.kg-1 group, but the same dose after 8 weeks and a higher dose (200 mg.kg-1) blunted this effect. A higher dose was also related to decrease in food intake. These data suggest that PABM can improve satiety and aerobic performance, but its effect depends on the dose and time of consumption.

Effect of molar mass and size of non-alcoholic beer fractions and their relevance toward palate fullness intensity

Palate fullness intensity and mouthfeel descriptors are essential sensory characteristics of non-alcoholic beers (NABs). The descriptor's perception might be influenced by the molar distribution of the non-volatile matrix in cereal-based beverages like NABs. However, only limited information is available on the molar mass of different substances in NABs. This study investigated the role of weight average molar mass (M_w) and size of NABs fractions and their relation to sensory perception. Industrialized bottom-fermented NABs (n = 28) from the German market and NABs produced by different methods were used in this study. A trained sensory panel evaluated palate fullness intensity, mouthfeel, and basic taste descriptors (as additional quality parameters). Asymmetric flow field-flow fractionation was used to fractionate NABs, while M_w was determined by multi-angle light scattering and differential refractive index detectors. The NABs were fractionated into three groups containing different substances: proteins, proteins-polyphenol complexes (P-PC) and low molar mass (non-)starch polysaccharides (LN-SP), and high molar mass (non-)starch polysaccharides (HN-SP). The M_w range of proteins was 18.3-41 kDa, P-PC and LN-SP 43-122.6 kDa, and HN-SP 0.40-2.18·10³ kDa. Harmony, defined as the sweet and sour ratio, influenced the palate fullness intensity perception. In the harmonic samples (sour/sweet sensory balanced), the size of HN-SP (> 25 nm) showed a positive correlation to palate fullness intensity. The results suggest the importance of dextrins, arabinoxylan, and β-glucan in modulating the sensory characteristics of harmonic bottom-fermented NABs.

Increasing Higher Alcohols and Acetates in Low-Alcohol Beer by Proteases

The market of non-alcoholic and low-alcohol beer has grown continuously thanks to the advocacy for healthy and responsible drinking. Non-alcoholic and low-alcohol products usually possess less higher alcohols and acetates and more aldehyde off-flavors due to the manufacturing processes. The employment of non-conventional yeasts partially mitigates this problem. In this study, we used proteases to optimize the wort amino acid profile for better aroma production during yeast fermentation. The design of experiments was applied to increase the leucine molar fraction, aiming to boost 3-methylbutan-1-ol and 3-methylbutyl acetate (banana-like aromas). This led to an increase from 7% to 11% leucine in wort after protease treatment. The aroma output in the subsequent fermentation, however, was yeast-dependent. An 87% increase of 3-methylbutan-1-ol and a 64% increase of 3-methylbutyl acetate were observed when Saccharomycodes ludwigii was used. When Pichia kluyveri was employed, higher alcohols and esters from valine and isoleucine were increased: 58% more of 2-methylpropyl acetate, 67% more of 2-methylbutan-1-ol, and 24% more of 2-methylbutyl acetate were observed. Conversely, 3-methylbutan-1-ol decreased by 58% and 3-methylbutyl acetate largely remained the same. Apart from these, the amounts of aldehyde intermediates were increased to a varying extent. The impact of such increases in aromas and off-flavors on the perception of low-alcohol beer remains to be evaluated by sensory analysis in future studies.

An Overview of Bioactive Phenolic Molecules and Antioxidant Properties of Beer: Emerging Trends

Beer is one of the oldest and most common beverages worldwide. The phenolic contents and antioxidant properties of beer are crucial factors in evaluating its nutritional quality. Special beers brewed with the addition of adjuncts are gaining in consumer preference, in response to demands for healthy food and new gustatory and olfactory stimuli. Many studies recently dealt with functional beers brewed with the addition of adjuncts. This review focuses on bioactive molecules, particularly the composition of phenolic compounds, and the antioxidant activity of beer. The current knowledge concerning the effect of the addition of adjuncts in the form of fruit, vegetables, herbs, and natural foods on the polyphenol content, antioxidant properties, and phenolic profile of beer is reviewed, with an outline of the emerging trends in brewing processes. Future studies need to complete the identification and characterization of the bioactive molecules in beer, as well as studying their absorption and metabolic fate in humans.

Controlled synthesis of distiller's grains biochar for turbidity removal in Baijiu

Resource utilization of distiller's grains (DGs) is crucial for realizing sustainable development of Baijiu industry. In the prevent investigation, a low-cost activated biochar (DGABC) suitable for removing turbidity from low-alcohol Baijiu was prepared by the controlled pyrolysis of DGs, followed by steam activation. The as-prepared biochar featured a large specific surface area (320-480 m²/g) and pore volume (0.45-0.47 cm³/g). Importantly, the DGABC possessed remarkable exterior hydrophily and interior lipophilicity, which guaranteed its good dispersion in alcohol-water system as well as an efficient adsorption to the components with long lipophilic chain. As a result, the DGABC could efficiently remove the turbidity in low-alcohol Baijiu, which was mainly derived from the long lipophilic chain components, such as ethyl palmitate. Meanwhile, most of the flavor esters that had a shorter lipophilic chain and lower hydrophobicity were well kept in the low-alcohol Baijiu. Therefore, this work provided a promising strategy for DGs recycling in Baijiu industry.

Experimental Study and Modeling of Beer Dealcoholization via Reverse Osmosis

The goals of the present investigation are to study and to model pale lager beer dealcoholization via reverse osmosis (RO). Samples were dealcoholized at a temperature of 15 ± 1 °C. An Alfa Laval RO99 membrane with a 0.05 m² surface was used. The flux values were measured during the separations. The ethanol content, extract content, bitterness, color, pH, turbidity, and dynamic viscosity of beer and permeate samples were measured. The initial flux values were determined using linear regression. The initial ethanol flux (JEtOH 0) values were calculated from the initial flux values and the ethanol content values. A 2^P full factorial experimental design was applied, and the factors were as follows: transmembrane pressure (TMP): 10, 20, 30 bar; retentate flow rate (Q): 120, 180, 240 L/h; JEtOH 0 was considered as the response. The effect sizes of the significant parameters were calculated. The global maximum of the objective function was found using a self-developed Grid Search code. The changes in the analytical parameters were appropriate. The TMP had a significant effect, while the Q had no significant effect on the JEtOH 0. The effect size of the TMP was 1.20. The optimal value of the factor amounted to TMP = 30 bar. The predicted JEtOH 0 under the above conditions was 121.965 g/m² h.

Novel Saccharomyces cerevisiae × Saccharomyces mikatae Hybrids for Non-alcoholic Beer Production

The popularity of non-alcoholic beers has been increasing over the past few years. Maltose-negative strains of different genera are frequently used to obtain beers of low alcohol content. S. cerevisiae hybrids with other Saccharomyces species offer interesting inherited flavour characteristics; however, their use in non-alcoholic beer production is rare. In this work, we constructed six hybrids of maltose-negative S. cerevisiae parental strains (modified to produce higher amounts of organic acids) and S. mikatae (wild-type). Growth behaviour, osmotolerance and fermentation features of the offspring were compared with parental strains. One hybrid with mitochondrial DNA inherited from both parents was used to produce non-alcoholic beer in which organic metabolites were evaluated by HPLC and HS-SPME-GC-MS. This hybrid produced non-alcoholic beer (≤0.05% (v/v)) with an increased organic acid content, just as its parent S. cerevisiae, but without producing increased amounts of acetic acid. The beer had a neutral aromatic profile with no negative off-flavours, similar to the beer produced by the parent S. mikatae, which was used for the first time to produce non-alcoholic beer. Overall, both parents and hybrid yeast produced non-alcoholic beers with increased amounts of higher alcohols compared with esters.

Valorization of Spent Brewer’s Yeast for the Production of High-Value Products, Materials, and Biofuels and Environmental Application

Spent brewer’s yeast (SBY) is a byproduct of the brewing industry traditionally used as a feed additive, although it could have much broader applications. In this paper, a comprehensive review of valorization of SBY for the production of high-value products, new materials, and biofuels, as well as environmental application, is presented. An economic perspective is given by mirroring marketing of conventional SBY with innovative high-value products. Cascading utilization of fine chemicals, biofuels, and nutrients such as proteins, carbohydrates, and lipids released by various SBY treatments has been proposed as a means to maximize the sustainable and circular economy.

Exploiting Non-Conventional Yeasts for Low-Alcohol Beer Production

Non-Saccharomyces yeasts represent a very appealing alternative to producing beers with zero or low ethanol content. The current study explores the potential of seven non-Saccharomyces yeasts to produce low-alcohol or non-alcoholic beer, in addition to engineered/selected Saccharomyces yeasts for low-alcohol production. The yeasts were first screened for their sugar consumption and ethanol production profiles, leading to the selection of strains with absent or inefficient maltose consumption and consequently with low-to-null ethanol production. The selected yeasts were then used in larger-scale fermentations for volatile and sensory evaluation. Overall, the yeasts produced beers with ethanol concentrations below 1.2% in which fusel alcohols and esters were also detected, making them eligible to produce low-alcohol beers. Among the lager beers produced in this study, beers produced using Saccharomyces yeast demonstrated a higher acceptance by taster panelists. This study demonstrates the suitability of non-conventional yeasts for producing low-alcohol or non-alcoholic beers and opens perspectives for the development of non-conventional beers.

Alcohol-free and low-alcohol beers: Aroma chemistry and sensory characteristics

Alcohol-free beers have gained popularity in the last few decades because they provide a healthier alternative to alcoholic beers and can be more widely consumed. Consumers are becoming more aware of the benefits of reducing their alcohol consumption, and this has increased the sales of nonalcoholic alternatives. However, there are still many challenges for the brewing industry to produce an alcohol-free beer that resembles the pleasant fruity flavor and overall sensory experience of regular beers. The aim of this review is to give a comprehensive overview of alcohol-free beer focusing on aroma chemistry. The formation of the most important aroma compounds, such as Strecker aldehydes, higher alcohols, and esters, is reviewed, aiming to outline the gaps in current knowledge. The role of ethanol as a direct and indirect flavor-active compound is examined separately. In parallel, the influence of the most common methods to reduce alcohol content, such as physical (dealcoholization) or biological, on the organoleptic characteristics and consumer perception of the final product, is discussed.

Systematic Parameter Estimation and Dynamic Simulation of Cold Contact Fermentation for Alcohol-Free Beer Production

Global demand for Low-Alcohol Beer (LAB) and Alcohol-Free Beer (AFB) has surged due to flavor attributes, health benefits, and lifestyle changes, prompting efforts for process intensification. This paper aims to offer a detailed modelling basis for LAB manufacturing study and optimisation. A first-principles dynamic model for conventional beer manufacturing has been re-parameterized and used for dynamic simulation of Cold Contact Fermentation (CCF), an effective LAB and AFB production method, with concentrations tracked along plausible temperature manipulation profiles. Parameter estimation is pursued using industrial production data, with a detailed local sensitivity analysis portraying the effect of key parameter variation on sugar consumption, ethanol production, and key flavor component (ethyl acetate and diacetyl) evolution during (and final values after) CCF. Ethyl acetate (esters in general) affecting fruity flavors emerge as most sensitive to CCF conditions.

Defining No and Low (NoLo) Alcohol Products

Reducing the alcoholic strength in beverages as a strategy to reduce harmful alcohol use has been proposed by multilateral institutions such as the World Health Organization and governments worldwide. Different industrial and artisanal techniques are used to achieve low-alcohol content beverages. Therefore, regulations regarding the content of alcohol in beverages and strategies to monitor compliance are important, because they are the main reason for classification of the beverages and are central to their categorization and market labelling. Furthermore, analytical techniques with adequate sensitivity as low as 0.04% vol are necessary to determine the alcohol ranges necessary for classification. In this narrative review, the definitions of no and low (NoLo) alcohol products are described and the differences in the legal definitions of these products in several regions of the world are highlighted. Currently, there is clearly confusion regarding the terminology of "no", "free", "zero", "low", "light", or "reduced" alcohol products. There is an urgent need for global harmonization (e.g., at the Codex Alimentarius level) of the definitions from a commercial perspective and also to have common nomenclature for science and for consumer information.

Non-starch polysaccharides in beer and brewing: A review of their occurrence and significance

It has become apparent that beer (both alcoholic and nonalcoholic) contains appreciable amounts of non-starch polysaccharides, a broad subgroup of dietary fiber. It is worth noting that the occurrence of non-starch polysaccharides in alcoholic beer does not imply this should be consumed as a source of nutrition. But the popularity of nonalcoholic beer is growing, and the lessons learnt from non-starch polysaccharides in brewing can be largely translated to nonalcoholic beer. For context, we briefly review the origins of dietary fiber, its importance within the human diet and the significance of water-soluble dietary fiber in beverages. We review the relationship between non-starch polysaccharides and brewing, giving focus to the techniques used to quantify non-starch polysaccharides in beer, how they affect the physicochemical properties of beer and their influence on the brewing process. The content of non-starch polysaccharides in both regular and low/nonalcoholic beer ranges between 0.5 - 4.0 g/L and are predominantly composed of arabinoxylans and β-glucans. The process of malting, wort production and filtration significantly affect the soluble non-starch polysaccharide content in the final beer. Beer viscosity and turbidity are strongly associated with the content of non-starch polysaccharides.

Potential of non-Saccharomyces yeast to produce non-alcoholic beer

Recently, non-Saccharomyces yeast have become very popular in wine and beer fermentation. Their interesting abilities introduce novel aromatic profiles to the fermented product. In this study, screening of eight non-Saccharomyces yeast (Starmerella bombicola, Lindnera saturnus, Lindnera jadinii, ZygoSaccharomyces rouxii, Torulaspora delbrueckii, Pichia kluyveri, Candida pulcherrima, and Saccharomycodes ludwigii) revealed their potential in non-alcoholic beer production. Conditions for non-alcoholic beer production were optimised for all strains tested (except T. delbrueckii) with the best results obtained at temperature 10 to 15 °C for maximum of 10 days. Starmerella bombicola, an important industrial producer of biosurfactants, was used for beer production for the first time and was able to produce non-alcoholic beer even at 20 °C after 10 days of fermentation. Aromatic profile of the beer fermented with S. bombicola was neutral with no negative impact on organoleptic properties of the beer. The most interesting organoleptic properties were evaluated in beers fermented with L. jadinii and L. saturnus, which produced banana-flavoured beers with low alcohol content. This work confirmed the suitability of mentioned yeast to produce non-alcoholic beers and could serve as a steppingstone for further investigation.

New Approaches for the Fermentation of Beer: Non-Saccharomyces Yeasts from Wine

Non-Saccharomyces yeasts represent a very attractive alternative for the production of beers with superior sensory quality since they are able to enhance the flavour of beer. Furthermore, they can produce beers with low ethanol content due to the weak fermentative capacity of a large percentage of non-Saccharomyces species. The objective of this study was to evaluate the ability of 34 non-Saccharomyces yeast strains isolated from Madrilenian agriculture to produce a novel ale beer. The non-Saccharomyces yeast strains were screened at two scales in the laboratory. In the first screening, those with undesirable aromas were discarded and the selected strains were analysed. Thirty-three volatile compounds were analysed by GC, as well as melatonin production by HPLC, for the selected strains. Thirteen strains were then fermented at a higher scale in the laboratory for sensory evaluation. Only yeast strains of the species Schizosaccharomyces pombe and Lachancea thermotolerans were able to complete fermentation. Species such as Torulaspora delbrueckii, Metschnikowia pulcherrima, Wickerhamomyces anomalus, Hanseniaspora vineae, and Hanseniaspora guilliermondii could be used both for production of low ethanol beers and co-fermentation with a Saccharomyces yeast to improve the organoleptic characteristics of the beer. In addition, for these strains, the levels of melatonin obtained were higher than the concentrations found for Saccharomyces strains subjected to the same study conditions. The selected strains can be used in future trials to further determine their viability under different conditions and for different purposes.

Maltose-Negative Yeast in Non-Alcoholic and Low-Alcoholic Beer Production

Although beer is a widely used beverage in many cultures, there is a need for a new drinking alternative in the face of rising issues such as health concerns or weight problems. However, non-alcoholic and low-alcoholic beers (NABLAB) still have some sensory problems that have not been fully remedied today, such as “wort-like”/”potato-like” flavours or a lack of aroma. These defects are due to the lack of alcohol (and the lack of the aldehyde-reducing effect of alcohol fermentation), as well as production techniques. The use of new yeast strains that cannot ferment maltose—the foremost sugar in the wort—is highly promising to produce a more palatable and sustainable NABLAB product because production with these yeast strains can be performed with standard brewery equipment. In the scientific literature, it is clear that interest in the production of NABLAB has increased recently, and experiments have been carried out with maltose-negative yeast strains isolated from many different environments. This study describes maltose-negative yeasts and their aromatic potential for the production of NABLAB by comprehensively examining recent academic studies.

Elucidation of aroma compounds in passion fruit (Passiflora alata Ait) using a molecular sensory approach

In this experiment, Guangxi passion fruit was used as the raw material for natural aroma extraction using the spinning cone column (Spinning Cone Column, SCC) technique. In combination with the semi-quantitative method, the aroma characteristics of the raw pulp (raw whole-fruit puree, PU) before SCC processing, residue (Residue, RS) and extract (Extract, EX) after SCC processing, and passion fruit juice (Juice, JU) were evaluated for their aroma characteristics using headspace gas chromatography-mass spectrometry (HS-SPME-GC-MS), gas chromatography-ion mobility spectrometry (GC-IMS), electronic nose, and sensory evaluation. As a result, a total of 110 aroma substances were detected in four samples, and 33, 38, 73, and 28 aroma components were detected from PU, RS, EX, and JU, respectively. There are 50 compounds in EX with concentrations greater than 10 μg/kg, and 19 of them had OAV values greater than 1, including β-Ionone and linalool, which contributed significantly to the aroma. The aroma profiles and characteristics were further analyzed for JU and EX using the e-nose sensor, and it was found that both showed similar aroma profiles. The sensory evaluation results were also in general agreement with the results obtained from the electronic nose, with EX having mainly "floral", "fruity," and "sweet" aromas. The results demonstrated that the spinning cone column technique can increase the fresh and natural fruity aroma of passion fruit in the extract, which has the effect of enriching the aroma and improving the aftertaste. This study will make a foundation for passion fruit SCC extract application in drinks. PRACTICAL APPLICATIONS: Compared with traditional extraction technology, spinning cone column technology has the advantages of high mass transfer efficiency, short extraction time, a wide range of temperature control, and the most complete extracted flavor substances, which greatly reduces the damage degree of heat-sensitive flavor substances and condense aroma. It is widely used in beverages, wine, dairy products, fruit and vegetable, spice essential oil, and other industries. Passion fruit flavor prepared by SCC technology has the advantages of high purity and high concentration, which can be used in solid drinks, baked food, convenience food, tobacco, perfume, and other products. Besides, GC-IMS is an efficient and rapid new analytical technique, which has been widely used in the flavor analysis of volatile organic compounds in food and traditional Chinese medicine samples.

Membrane Dialysis for Partial Dealcoholization of White Wines

Membrane dialysis is studied as a promising technique for partial dealcoholization of white wines. The performance of three membrane processes applied for the partial dealcoholization of white wines of the Verdejo variety has been studied in the present work. Combination of Nanofiltration with Pervaporation, single step Pervaporation and, finally, Dialysis, have been applied to white wines from same variety and different vintages. The resulting wines have been chemically and sensorially analyzed and results have been compared with initial characteristics of the wines. From the results obtained, we can conclude that all procedures lead to significant alcohol content reduction (2%, 0.9% and 1.23% v/v respectively). Nevertheless, the best procedure consists in the application of Dialysis to the wines which resulted in a reasonable alcohol content reduction while maintaining organoleptic properties (only 14 consumers were able to distinguish the filtered and original wines, with 17 consumers needed to be this differences significant) and consumer acceptability of the original wine. Therefore, membrane dialysis, as a method of partial dealcoholization of white wines, has undoubted advantages over other techniques based on membranes, which must be confirmed in subsequent studies under more industrial conditions. This work represents the first application of Dialysis for the reduction of alcohol content in wines.

Safety and Protective Activities of Manufactured Alcohol-Free Beers

Nowadays, a general interest in improving health in order to achieve better conditions of life is increasing. Diet is a complex factor affecting health conditions. We analysed the biological activities of three types of alcohol-free lager beer (a blond, a pale-blond and a stout beer) as well as epicatechin gallate (ECG) as one of their most abundant phenols with the aim of revealing them as nutraceuticals. For that purpose, we carried out safety and protective assays of the tested substances in the well-known Drosophila melanogaster animal model. Moreover, chemoprevention studies on human leukaemia cells (HL-60) in an in vitro model were carried out to evaluate the viability and genomic damage potential of the studied compounds on the tumour cell line. Results suggest the safety properties of all compounds, although pale-blond and stout beer only showed genotoxic activity at the lowest concentrations assayed. Moreover, alcohol-free beers and phenols were able to protect against H2O2 oxidative damage as well as to induce an increase in longevity with an improvement of the quality of life in the in vivo animal model assayed. Promising results were obtained with the alcohol-free beers and ECG in the in vitro assays with human leukaemia cells as they inhibited the tumour cells’ growth, induced DNA damage and modified the methylation status of such a cancer cell line. To sum up, alcohol-free beers should be of interest not only because of their reduced calories and isotonic properties but because they can be recognised as nutraceutical substances.

Effect of Production Technique on Pilsner-Style Non-Alcoholic Beer (NAB) Chemistry and Flavor

The sensory, volatile, and physiochemical profiles of nineteen commercial non-alcoholic pilsner-style beers produced by different production techniques were analyzed and compared with a dry-hopped non-alcoholic IPA. NABs made only with either physical dealcoholization or restricted fermentations differed significantly in chemistry and flavor. Generally, NABs produced by restricted fermentations were the most worty, thick, and sweet, whereas NABs that were physically dealcoholized had the lowest taste/aroma intensities and were the sourest, most thin, and least sweet. Interestingly, the method of dealcoholization had a minor impact on the flavor profile. The use of maltose intolerant yeast as well as the implementation of combined treatments, such as blending dealcoholized beer with beer containing alcohol, were the techniques found to produce NABs with more harmonious and multifaceted chemical and flavor profiles. NABs with increased hop aroma volatiles were the most harmonious, particularly highlighted by the NA IPA reference. Even though dry-hopped character might be atypical for pilsner-style beer, dry-hopping appears as a simple application to produce NABs with more harmonious flavor.

Repurposing brewery contaminant yeast as production strains for low-alcohol beer fermentation

A number of fungal isolates were recently obtained from a survey of the microbiota of multiple breweries and brewery products. Here, we sought to explore whether any of these brewery contaminants could be repurposed for beneficial use in beer fermentations, with particular focus on low-alcohol beer. There were 56 yeast strains first screened for the utilization of different carbon sources, ability to ferment brewer's wort, and formation of desirable aroma compounds. A number of strains appeared maltose-negative and produced desirable aromas without obvious off-flavours. These were selected for further scaled-up wort fermentations. The selected strains efficiently reduced wort aldehydes during fermentation, thus eliminating undesirable wort-like off-flavours, and produced a diverse volatile aroma profile. Two strains, Trigonopsis cantarellii and Candida sojae, together with a commercial Saccharomycodes ludwigii reference strain, were selected for 30-L-scale wort fermentations based on aroma profile and similarity to a commercial reference beer during sensory analysis using projective mapping. Both strains performed comparably to the commercial reference, and the T. cantarellii strain in particular, produced low amounts of off-flavours and a significantly higher amount of the desirable monoterpene alcohol trans-geraniol. The strain was also sensitive to common food preservatives and antifungal compounds and unable to grow at 37°C, suggesting it is relatively easily controllable in the brewery, and appears to have low risk of pathogenicity. This study shows how the natural brewery microbiota can be exploited as a source of non-conventional yeasts for low-alcohol beer production.

Techniques for Dealcoholization of Wines: Their Impact on Wine Phenolic Composition, Volatile Composition, and Sensory Characteristics

The attention of some winemakers and researchers over the past years has been drawn towards the partial or total dealcoholization of wines and alcoholic beverages due to trends in wine styles, and the effect of climate change on wine alcohol content. To achieve this, different techniques have been used at the various stages of winemaking, among which the physical dealcoholization techniques, particularly membrane separation (nanofiltration, reverse osmosis, evaporative perstraction, and pervaporation) and thermal distillation (vacuum distillation and spinning cone column), have shown promising results and hence are being used for commercial production. However, the removal of alcohol by these techniques can cause changes in color and losses of desirable volatile aroma compounds, which can subsequently affect the sensory quality and acceptability of the wine by consumers. Aside from the removal of ethanol, other factors such as the ethanol concentration, the kind of alcohol removal technique, the retention properties of the wine non-volatile matrix, and the chemical-physical properties of the aroma compounds can influence changes in the wine sensory quality during dealcoholization. This review highlights and summarizes some of the techniques for wine dealcoholization and their impact on wine quality to help winemakers in choosing the best technique to limit adverse effects in dealcoholized wines and to help meet the needs and acceptance among different targeted consumers such as younger people, pregnant women, drivers, and teetotalers.

Production, Consumption, and Potential Public Health Impact of Low- and No-Alcohol Products: Results of a Scoping Review

Switching from higher strength to low- and no-alcohol products could result in consumers buying and drinking fewer grams of ethanol. We undertook a scoping review with systematic searches of English language publications between 1 January 2010 and 17 January 2021 using PubMed and Web of Science, covering production, consumption, and policy drivers related to low- and no-alcohol products. Seventy publications were included in our review. We found no publications comparing a life cycle assessment of health and environmental impacts between alcohol-free and regular-strength products. Three publications of low- and no-alcohol beers found only limited penetration of sales compared with higher strength beers. Two publications from only one jurisdiction (Great Britain) suggested that sales of no- and low-alcohol beers replaced rather than added to sales of higher strength beers. Eight publications indicated that taste, prior experiences, brand, health and wellbeing issues, price differentials, and overall decreases in the social stigma associated with drinking alcohol-free beverages were drivers of the purchase and consumption of low- and no-alcohol beers and wines. Three papers indicated confusion amongst consumers with respect to the labelling of low- and no-alcohol products. One paper indicated that the introduction of a minimum unit price in both Scotland and Wales favoured shifts in purchases from higher- to lower-strength beers. The evidence base for the potential beneficial health impact of low- and no-alcohol products is very limited and needs considerable expansion. At present, the evidence base could be considered inadequate to inform policy.

Transfer of Ethanol and Aroma Compounds by Varying Specific Process Parameters in the Thermal Dealcoholisation of Beer

Dealcoholisation of beer has gained prominence over the last decade. A well-known procedure involves the combination of a rectification column for thermal dealcoholisation and a downstream column for aroma recovery. However, the recovery of valuable fermentation by-products is rarely performed due to limited data about the enrichment and depletion of ethanol and aromatic compounds. The influence of operating conditions on the transfer of ethanol and aroma compounds to the recovery fluid, henceforth, ‘aromawater’, has not yet been fully explored. Therefore, this study involved examining how ethanol concentration and aroma compounds in the aromawater are affected by the condenser temperature and reflux rate during thermal dealcoholisation. The aim was to obtain an aromawater having a maximum level of valuable aroma substances and a minimum level of ethanol for re-blending with non-alcoholic beer, hypothetically causing aroma intensification. An industrial system was used for sample production. Ethanol as well as higher alcohols and ester concentrations were analysed in the different material flows, and mass balances were thus compiled. Sensory analysis was performed to evaluate the beer aroma’s intensification as a sustainable industrial application. The obtained results indicate that increased condenser temperature was associated with increased aroma concentrations in the aromawater. If the temperature of the condenser’s coolant exceeded 15 °C, dealcoholisation < 0.05% abv could not be guaranteed. A higher reflux rate led to higher concentrations of fermentation by-products in the aromawater. Finally, the aroma profile of three non-alcoholic beers (0.0% abv, 0.5% abv after blending with original beer, and 0.5% abv after blending with aromawater) were evaluated. By blending, the attributes ‘estery’ and ‘flowery’ were assessed as dominant. The effect was more pronounced with aromawater than with the original beer.

Recent innovations in the production of selected specialty (non-traditional) beers

Customer demand for product diversity is the key driving force for innovations in the brewing industry. Specialty beers are regarded as a distinct group of beers different from two major types, lagers and ales, without established definitions or boundaries. Specialty beers, including low- to no-alcohol beer, low carbohydrate beer, gluten-free beer, sour beer, probiotic beer, and enriched beer, are exclusively brewed and developed keeping in mind their functionality, the health and wellbeing of the consumer, and emerging market trends. Compared with conventional beer-brewing, the production of specialty beers is technologically challenging and usually requires additional process steps, unique microorganisms, and special equipment, which in turn may incur additional costs. In addition, the maintenance of quality and stability of the products as well as consumer acceptability of the products are major challenges to successful commercialization. A harmonious integration of traditional brewing practices and modern technological approaches may hold potential for future developments. In the present review, latest developments in the fermentative production of selected specialty beers are discussed.

Role of Yeasts in the Brewing Process: Tradition and Innovation

Nowadays, in the beer sector, there is a wide range of products, which differ for the technologies adopted, raw materials used, and microorganisms involved in the fermentation processes. The quality of beer is directly related to the fermentation activity of yeasts that, in addition to the production of alcohol, synthesize various compounds that contribute to the definition of the compositional and organoleptic characteristics. The microbrewing phenomenon (craft revolution) and the growing demand for innovative and specialty beers has stimulated researchers and brewers to select new yeast strains possessing particular technological and metabolic characteristics. Up until a few years ago, the selection of starter yeasts used in brewing was exclusively carried out on strains belonging to the genus Saccharomyces. However, some non-Saccharomyces yeasts have a specific enzymatic activity that can help to typify the taste and beer aroma. These yeasts, used as a single or mixed starter with Saccharomyces strains, represent a new biotechnological resource to produce beers with particular properties. This review describes the role of Saccharomyces and non-Saccharomyces yeasts in brewing, and some future biotechnological perspectives.

Assessing the sensory and physicochemical impact of reverse osmosis membrane technology to dealcoholize two different beer styles

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Reverse osmosis results in significant losses in volatile compounds and modified sensory profiles.

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Volatile losses appear to be related to compound structure, not compound size.

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Reverse osmosis efficiency varies between beer styles, with longer processing times for stouts.

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Reverse osmosis membranes are susceptible to fouling over time, affecting overall product quality.

A pilot scale dealcoholisation unit fitted with reverse osmosis (RO) membranes was used to directly compare two beer matrices (stout, lager, ~ 5% ABV) and their dealcoholized counterparts (~0.5% ABV), for physicochemical properties (volatiles, pH, ABV, polyphenols, bitterness) and sensory profiles using a trained descriptive panel (n = 12). The efficiency and consistency of RO membranes were evaluated by replicate dealcoholisation trials (n = 3) for each beer. Statistical analysis revealed significant reductions (p < 0.05) in key volatile compounds with linear structures (ethyl octanoate, octan-1-ol) compared to those with increased levels of branching (3-methylbutyl acetate, 2-methylpropan-1-ol). Significant reductions (p < 0.0001) in ‘fruity/estery’, ‘alcoholic/solvent’, ‘malty’, ‘sweetness’ and ‘body’ sensory attributes were also discovered. Finally, longer processing times for the stout across replicate trials suggested membrane clogging, whilst differences in volatile reduction suggested membrane fouling. This novel research proposes compound structure, rather than compound size, impacts RO membrane permeability and resulting sensory quality.

Impact of Dealcoholization by Osmotic Distillation on Metabolic Profile, Phenolic Content, and Antioxidant Capacity of Low Alcoholic Craft Beers with Different Malt Compositions

Beer antioxidants originate mainly from malts, classified as colored, caramel, and roasted, according to the malting process. This study aimed to characterize, in terms of phenolic antioxidants, three types of Pale Ale craft beers brewed using increasing percentage of dark malt (0, 5, and 15% Caraamber malt, called PA100, PA95, PA85, respectively) and to evaluate the impact of dealcoholization by osmotic distillation (OD) on the same antioxidants. All the alcoholic (PA, 6.2-6.8 vol %) and low alcoholic (LA-PA, 1 vol %) beers were analyzed by HPLC-ESI-MS/MS, total phenolic content (TPC), and antioxidant activity (AA): similar phenolic profiles were evidenced and 43 compounds identified or tentatively identified. Some differences were found among PA100, PA95, and PA85: PA85 was richer in free phenolic compounds (10.55 mg/L) and had a higher TPC (463.7 GAE mg/L) and AA (852.1 TE mg/L). LA-PA beers showed the same phenolic profile and similar TPC and AA compared to PA beers; however, there were some differences regarding LA-PA85 (5.91 mg/L). Dealcoholization by OD seemed to weakly affect the phenolic fraction. ESI-MS/MS infusion experiments evidenced oligosaccharides, small organic acids, and amino acids, whose presence was confirmed and quantitated by NMR: besides ethanol and other alcohols, weak to strong loss of low-molecular-weight metabolites was evidenced in LA-PA beers.

The Role of Bioactive Phenolic Compounds on the Impact of Beer on Health

This review reports recent knowledge on the role of ingredients (barley, hop and yeasts), including genetic factors, on the final yield of phenolic compounds in beer, and how these molecules generally affect resulting beer attributes, focusing mainly on new attempts at the enrichment of beer phenols, with fruits or cereals other than barley. An entire section is dedicated to health-related effects, analyzing the degree up to which studies, investigating phenols-related health effects of beer, have appropriately considered the contribution of alcohol (pure or spirits) intake. For such purpose, we searched Scopus.com for any kind of experimental model (in vitro, animal, human observational or intervention) using beer and considering phenols. Overall, data reported so far support the existence of the somehow additive or synergistic effects of phenols and ethanol present in beer. However, findings are inconclusive and thus deserve further animal and human studies.

Understanding the sensory and physicochemical differences between commercially produced non-alcoholic lagers, and their influence on consumer liking

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Variation in sensory and physicochemical profiles not explained by production method.

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Differences instead were discussed to be due to pre and post processing methods.

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Overall consumer liking could be optimised by mixing different production techniques.

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Five patterns of consumer liking identified, related to sensory characteristics.

This study aimed to investigate the sensory and physicochemical differences of a range of commercial non-alcoholic lagers, as well as their influence on overall liking. Using physicochemical analysis and modified quantitative descriptive analysis (QDA) with a trained panel (n = 10) eighteen commercial non-alcoholic lagers, made using different production methods, were assessed. A subset (eleven), representing the sensory space were also assessed for hedonic liking using consumers (n = 104). Overall, it showed a clear variety of non-alcoholic lagers were selected, with different clusters of samples found with identifiable characteristics. Production methods were explored as a possible explanation for the differences in characteristics, however these did not fully explain the clusters and therefore other factors, such as pre or post processing methods are discussed. In terms of overall liking, five clusters of consumers were discovered with different patterns of liking, confirming that a wide range of non-alcoholic lagers are needed to satisfy all consumers.

Evaluation of mixed-fermentation of Saccharomyces cerevisiae with Saprochaete suaveolens to produce natural fruity beer from industrial wort

Fruity beers can be promoted through production of flavoring compounds during fermentation by partial replacement of brewing yeast by non-conventional-yeasts with high aroma production abilities. We evaluated here the use of a wild Saprochaete suaveolens strain, producing atypical aroma compounds, to produce new natural fruity beer, while keeping classical production conditions used in brewing industry. S. suaveolens was inoculated as starter of culture during beer fermentation and the fermentation performance was evaluated through measurement of several physicochemical parameters. The aroma profile of the engineered beers was monitored using HS-SPME GC/MS. The results showed that high fruity aroma and low-ethanol content beers were obtained through single-fermentation using S. suaveolens. We also demonstrated that during mixed-fermentation, S. suaveolens maintained high metabolic activity and allowed production of beer enriched with fruity aroma. Production of high or low ethanol content fruity beer could be achieved by varying the composition of the starter of culture.