Malt is the main raw material for beer production, which determines not only its taste and aroma profile, but to a large extent its biological value, as well. The aim of the present research was to determine the antioxidant profile of different malt types as a basis for the development of new types of beer with increased antioxidant activity. In the present study the main brewing characteristics, the phenolic profile and the antioxidant potential of 20 malt types used in craft breweries in Bulgaria have been examined. The main brewing characteristics have been determined by the standardized methods of the European Brewing Convention. Malt phenolic content was determined by two methods, and antioxidant potential by five different methods. Based on a statistical factor analysis performed by the principal component analysis, it was confirmed that there was a relationship between malt color and phenolic compounds content. The principal component analysis confirmed that there was a link between the content of the Maillard reaction products and malt biological activity. Malts with the highest degree of heat treatment were characterized by the highest antioxidant activity, which was due to the content of Maillard reaction products with antioxidant capacity.

Beer production has over a thousand-year tradition, but its development in the present continues with the introduction of new technological and technical solutions. The methods for modeling and optimization in beer production through an applied analytical approach have been discussed in the present paper. For this purpose, the parameters that are essential for the main processes in beer production have been considered—development of malt blends, guaranteeing the main brewing characteristics; obtaining wort through the processes of mashing, lautering and boiling of wort; fermentation and maturation of beer. Data on the mathematical dependences used to describe the different stages of beer production (one-factor experiments, modeling of mixtures, experiment planning, description of the kinetics of microbial growth, etc.) and their limits have been presented, and specific research results of various authors teams working in this field have been cited. The independent variables as well as the objective functions for each stage have been defined. Some new trends in the field of beer production have been considered and possible approaches for their modeling and optimization have been highlighted. The paper suggests a generalized approach to describe the main methods of modeling and optimization, which does not depend on the beer type produced. The proposed approaches can be used to model and optimize the production of different beer types, and the conditions for their application should be consistent with the technological regimes used in each case. The approaches for modeling and optimization of the individual processes have been supported by mathematical dependencies most typical for these stages. Depending on the specific regimes and objectives of the study, these dependencies can be adapted and/or combined into more general mathematical models. Some new trends in the field of beer production have been considered and possible approaches for their modeling and optimization have been highlighted.

The review discussed the fundamental characteristics of grape phenolic compounds, focusing on their chemical properties and significance in winemaking. Given the higher phenolic content in red wines, particular attention is devoted to attributes such as pigmentation, co-pigmentation, bitterness, and interactions with proteins—key contributors to the perception of astringency. Phenolic compounds undergo substantial qualitative and quantitative transformations during grape ripening, which affect both their inherent properties and their extractability from solid components such as grape skins and seeds. The review also examined extractability dynamics and provides a concise overview of the analytical methods used to assess phenolic compounds in grapes and wine.

Wort can be used as a basis for functional beverages production because of its content of fibres, antioxidants and vitamins. The biological value of wort depends on the malt used and the mashing regime. Therefore, we investigated the main brewing characteristics (extract, pH, and colour), phenolic compounds content, and antioxidant activity (measured by DPPH, FRAP, CUPRAC, ABTS, and ORAC) of wort, produced by Vienna, Melanoidin, Caramel pils and Special X malt or mixture of them. The results obtained were used for the modelling and optimisation of malt mixture that can be used for the production of functional beverages. Optimisation was made on the basis of wort extract, total phenolic compounds (measured by Folin–Ciocalteu method), and antioxidant activity, measured by DPPH, FRAP, and ORAC methods. Although optimised variants with high content of Special X malt showed highest antioxidant activity, they had an unpleasant taste and slow mash filtration rate. Therefore, the variant with 24.2% Vienna, 51.8% Melanoidin, 20% Caramel pils, and 4% Special X malts was chosen for the production of functional wort-based beverages.

The application of continuous fermentation with immobilized cells in brewing is a challenge because of problems with carrier selection and reactor design, which have economic impacts on the beer produced. Moreover, immobilization alters yeast physiology, which significantly affects beer flavor and aroma. Therefore, the aim of this study was to investigate the feasibility of a continuous fermentation system, consisting of a packed bed column bioreactor, containing lager brewing yeast, immobilized in alginate–chitosan microcapsules with a liquid core, in the primary beer fermentation. The results showed that the system entered in a stationary mode on the 3rd day and worked stably in this mode for 6 days. The “green” beer was taken at every 24 h at the output of the reactor and used for secondary fermentation with the yeast cells leaked from the capsules during the primary fermentation. The extract consumption, ethanol production, and pH change during primary and secondary fermentation were investigated. Some of the secondary yeast metabolites such as vicinal diketones, higher alcohols, esters, and aldehydes in “green” and final beers were determined and it was found that the flavor profile of the final beer was comparable to two industrially produced Bulgarian beers.