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Alcohol-free beers (AFBs) brewed by cold-contact fermentation exhibit a flavor reminiscent of wort which affects consumer acceptability. The aims of this study were to identify the odor-active compounds in AFB and elucidate the contribution of these to the overall aroma and worty character of the beer. Using a sensomics approach, 27 odor-active aroma compounds were identified and quantitated using gas chromatography–mass spectrometry. The most odor-active compound was methional (boiled potato-like aroma), followed by 3-methylbutanal (cocoa-like), ( E )-β-damascenone (apple, jam-like), 5-ethyl-3-hydroxy-4-methyl-2(5 H )-furanone (curry, spicy-like), and phenylacetaldehyde (floral, honey-like). The important contribution of these flavor compounds to the worty and honey aroma of AFB was determined by sensory assessment of the recombinate in a beer-like matrix with omission tests. The role of 5-ethyl-3-hydroxy-4-methyl-2(5 H )-furanone in AFB aroma was reported for the first time. The outcomes from this study are of relevance for the brewing industry to design strategies for the reduction of the wortiness of AFB.

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The use of vegetable proteins as food ingredient is becoming increasingly important due to their high versatility and environmental acceptability. This work describes a chemical characterization and techno-functional properties (emulsifying and foaming properties) of 3 protein fractions obtained from a protein-rich novel lupin variety, AluProt-CGNA(®) . This nongenetically modified variety have a great protein content in dehulled seeds (60.6 g protein/100 g, dry matter), which is higher than soybean and other lupin varieties. A simple procedure was utilized to obtain 3 different fractions by using alkali solubilization and isoelectric precipitation. Fractions 1 and 3 were mainly composed of protein and polysaccharides (NNE), whereas fraction 2 was mainly composed by protein (97%, w/w). Fraction 3 presented interesting and potential foaming properties in comparison to the other fractions evaluated in the study. Besides, its solubility, foaming and emulsifying capacity were practically not affected by pH variations. The 3 fractions also presented good emulsion stability, reaching values above a 95%. SDS-PAGE showed that fractions 1 and 2 contained mainly conglutin α, β, and δ, but in different ratios, whereas fraction 3 contained mainly conglutin γ and albumins. The results of this work will provide better understanding for the utilization of each protein fractions as potential ingredients in food industry.

The formation of multilayered interfaces around oil droplets in oil‐in‐water (O/W) emulsions provides a novel means of improving the quality and stability of many food products. In this work, a system of O/W emulsions containing lipid droplets stabilized by different ionic biopolymers was developed, and their stability under different environmental stresses was evaluated. The protein isolate from a new lupin variety (AluProt‐CGNA) and two polysaccharides—chitosan and xanthan gum—were utilized. AluProt‐CGNA protein‐stabilized emulsions were unstable to aggregation at pH values around their isoelectric point (pI 4.6) and to all the temperatures and salt concentrations evaluated in this study. However, in the presence of chitosan (0.06 wt%), the droplets showed good stability to aggregation from pH 3 to 6, at 30–90°C and at ≤100 mM NaCl. Adding xanthan gum (0.1 wt%) to the system improved emulsion stability from pH 4 to 7, where no phase separation was observed. This study showed that the stability of O/W emulsions containing protein (AluProt‐CGNA)‐coated lipid droplets under environmental stresses can be improved by adding certain concentrations of chitosan and xanthan gum. These findings have important implications for the design of encapsulation and delivery systems for lipophilic compounds in the food industries. Practical applications: The development of multilayer emulsions can be extremely useful to the encapsulation of lipophilic bioactive molecules for food applications, such as polyunsaturated fatty acids (PUFAs), flavors, vitamins, etc. Moreover, this technique provides a system for the creation of O/W emulsions with improved stability to environmental stresses, protection of oil phase, and controlled and triggered release of microencapsulated compounds. In this work, the design of stable O/W emulsions containing PUFAs rich oil droplets surrounded by multiple layer interfacial membranes from food grade ingredients, such as lupin proteins (AluProt‐CGNA), chitosan, and xanthan gum membranes; has been performed. The designed emulsion proved to be stable under different environmental stresses found in many food products. Moreover, thermal stability exhibited by these emulsions could also be an important characteristic for its use in food products. The diagram shows the formation of multilayer emulsions.

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.