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This study aimed to evaluate the quality parameters in probiotic yogurt produced with Brazilian red propolis to replace potassium sorbate used in conventional yogurt (CY). Microbiological stability and shelf life, physicochemical properties (pH, acidity, chemical composition, and fatty acids), and bioactive properties (phenolic compounds and antioxidant activity) were evaluated. The addition of red propolis (0.05%) to replace the potassium sorbate did not change the pH, acidity, fatty acid profile, chemical composition, or shelf life. Microbiological stability of at least 28 days was achieved, while a drastic reduction in the lactic acid bacteria content was observed in the CY during refrigeration storage. Phenolic total contents were higher than those of the control, and consequently, yogurt with red propolis showed higher antioxidant activity. PRACTICAL APPLICATION: The study indicates that Brazilian red propolis at 0.05% concentration to replace the potassium sorbate is an efficient alternative for use in yogurt production. The knowledge acquired about these types of Brazilian propolis provides an important contribution to food research in the discovery of new functional products to the market, seeking a healthier diet. Therefore, the produced yogurt proves to be an innovative product with functional and probiotic potential to be placed on the market.

The Institute of Brewing & Distilling Mead is a traditional alcoholic beverage obtained by fermenting must and can offer a solution to honey over-production and a way of valorizing honey of lower quality. The purpose of this study was to produce and characterize mead with different levels of sugars and alcohol obtained from honey from Melipona scutellaris. The honey used for mead preparation was analysed in order to ensure that it met the required quality standards. It was found that the alcoholic content and volatile acidity were outwith the limits established by Brazilian law. Mead legislation is based on the product obtained from Apis mellifera (‘honey bee’) honey and these results indicate the need to re-evaluate the standards established for this product in order to incorporate mead produced from honey from stingless bees of the genus Melipona. Copyright © 2018 The Institute of Brewing & Distilling. We thank the Coordination for the Improvement of Higher Education Personnel (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior) for granting a scholarship of the Institutional Program of Scholarships of Doctorate Sandwich Abroad to Samira Maria Peixoto Cavalcante da Silva, financial support for the project and a scholarship granted to Leticia M. Estevinho. We also thank the National Council for Scientific and Technological Development (Conselho Nacional de Desenvolvimento Científico e Tecnológico) for a research scholarship granted to Carlos Alfredo Lopes de Carvalho. We thank the Polytechnic Institute of Bragança, in particular to the Laboratory of Microbiology, for the development of the work. This work was supported by the strategic programme UID/BIA/04050/2013 (POCI-01-0145-FEDER-007569) funded by national funds through the FCT IP and by the ERDF through the COMPETE2020 – Programa Operacional Competitividade e Internacionalização. info:eu-repo/semantics/publishedVersion

Through honey's fermentation, diverse beverages can be obtained, among which is mead, an alcoholic drink with 8 to 18% of ethanol (v/v). Since honey is a matrix with a low nutrient concentration and other unfavourable growth conditions, several problems are usually encountered, namely delayed or arrested fermentations, unsatisfactory quality parameters and lack of uniformity of the final product, as well as unpleasant sensory properties. In this context, the aim of this work was to optimize mead production through honey-must supplementation with (a) salts, (b) vitamins or (c) salts+vitamins. The effects of the honey-must formulation on the fermentation kinetics, growth profile and physicochemical characteristics of final meads were evaluated. The results showed minor differences in the fermentation profile and time between fermentations with the different formulations. The growth profile was influenced more by the yeast strain than by the supplements added to the honey-must. In general, the honey-must composition did not influence meads' final characteristics, except regarding the SO < inf > 2 < /inf > concentration of the meads produced using the strain QA23. In summary, the addition of salts and/or vitamins to honey-must had no positive effects on the fermentation, growth profile or characteristics of the final products. The research presented in this paper was partially funded by the Fundação para a Ciência e Tecnologia (FCT) and by PTDC projects (contracts PTDC/AGR-ALI/68284/2006). A. P. Pereira is a recipient of a PhD grant from the FCT (SFRH/BD/45820/2008). info:eu-repo/semantics/publishedVersion

Honey is a natural product with recognized physical and chemical properties, which contribute to its biological activity. However, honey is currently being sold at low prices, making it imperative to find alternatives to make apiculture a viable national enterprise. One of these alternatives could be mead production. Despite the excellent properties of honey, mead production faces several problems, namely, delays and “pouts” fermentations, lack of product uniformity, and production of yeast off-flavors. Many factors might be related with these problems, such as honey variety, temperature, medium composition (vitamin and nitrogen content), fermentative yeast, and pH. Due to all these factors, mead production has decreased over the years. To overcome this situation, more research is needed to optimize the production of this beverage. This chapter presents a comprehensive review of previous research on mead production. It will focus on honey characterization and mead production. The first section covers honey composition and the way this affects honey properties, as well as important parameters that are indicators of honey quality. The second section discusses mead production, including fermentative microorganisms, fermentation conditions, and required postfermentation adjustments and maturation conditions. The final section focuses on the problems that must be surpassed and what the future holds for mead production.

O mel é um produto natural, ao qual são reconhecidas propriedades físicas e químicas que contribuem para a sua actividade biológica. No entanto, o mel actualmente, é comercializado a preços reduzidos, tornando-se imperioso encontrar alternativas que viabilizem as explorações apícolas nacionais. Uma destas alternativas passa pela produção de hidromel. Apesar das excelentes propriedades do mel, a produção de hidromel enfrenta alguns problemas, nomeadamente, atrasos e amuos da fermentação, falta de uniformidade do produto e produção de compostos, pelas leveduras, com aroma desagradável. Estes problemas podem estar associados ao facto das leveduras utilizadas na fermentação serem leveduras enológicas que, provavelmente, não estão adaptadas às condições de stress do mel. Este trabalho teve como objectivos a caracterização do mel da região de Trás-os-Montes (Nordeste de Portugal), a selecção de leveduras isoladas de mel para a produção de hidromel e a optimização das condições de produção de hidromel. A primeira parte do trabalho consistiu na caracterização do mel utilizado na produção de hidromel. O mel analisado mostrou ser um produto de qualidade, que cumpria os parâmetros estabelecidos na legislação portuguesa. Na segunda parte avaliou-se a capacidade de estirpes de Saccharomyces cerevisiae isoladas de mel português para produzir hidromel. Para tal, cinco estirpes isoladas de mel, uma estirpe de referência e uma estirpe comercial, utilizada em enologia, foram avaliadas e comparadas em termos da sua resistência ao sulfuroso, ao etanol, e stress osmótico. Todas as estirpes exibiram um comportamento semelhante às condições de stress estudadas. Destas estirpes foram seleccionadas a comercial e, aleatoriamente, duas estirpes isoladas de mel para a produção de hidromel. As três estirpes foram submetidas a fermentações com dois méis diferentes (um claro e um escuro) enriquecidos com dois suplementos (1: comercial; 2: desenvolvido pela equipa de investigação). Para avaliar o desempenho das fermentações determinou-se o crescimento da levedura e a produção de etanol, glicerol e ácido acético. As estirpes de Saccharomyces cerevisiae isoladas de mel mostraram ser apropriadas para a produção de hidromel. No entanto, é necessário ter em consideração as características do mel e dos suplementos utilizados na formulação do meio de fermentação. Honey is a natural product with recognized physical and chemical properties, which contribute to its biological activity. However, honey is currently being sold at low prices, making it imperative to find alternatives to make apiculture a viable national enterprise. One of these alternatives could be mead production. Despite the excellent properties of honey, mead production faces several problems, namely, delays and “pouts” fermentations, lack of uniformity of the product and production of off-flavours by the yeasts. These problems can be usually associated with the fact, the yeast used in fermentation are yeast wine, which probably will not be adapted to the stress of honey. The main objectives of this work were the characterization of Trás-os-Montes (Northeast Portugal) honey, the selection of yeasts isolated from honey for mead production and the optimization of conditions for mead production. The first part of the work consisted in the characterization of honey used in the mead production. The analysed honey has shown to be a quality product that met the parameters established in Portuguese legislation. In the second part, the ability of Saccharomyces cerevisiae strains isolated from Portuguese honey to produce mead was evaluated. So, five strains isolated from honey, a reference strain and a commercial strain used in oenology, were evaluated and compared in terms of their resistance to ethanol, sulphur dioxide and osmotic stress. All strains exhibited similar behaviour to the conditions of stress studied. Of these strains, for mead production it were selected two strains isolated from honey (randomly) and the commercial one. The three strains were subjected to fermentations with two different honeys (a light and a dark honeys) enriched with two supplements (1: commercial; 2: developed by research the team). To evaluate the fermentation performance it was determined the yeast growth and the production of ethanol, glycerol and acetic acid. The Saccharomyces cerevisiae strains isolated from honey had shown to be appropriate for mead production. However, it is necessary to have into account the characteristics of the honey and supplements used in the fermentation medium formulation. Projecto PTDC/AGR-ALI/68284/2006 Fundação para a Ciência e Tecnologia