This study evaluated the influence of tea, sucrose, and inoculum concentrations on green tea kombucha’s physicochemical properties and antioxidant capacity to optimize its production. The highest total phenolic content (98.61 mg GAE/100 mL) and radical scavenging activity for ABTS (9647.14 μmol/mL) and DPPH (6640.00 μmol/mL) were observed with 8 g/L of tea, 80 g/L of sucrose, and 30% inoculum. Principal Component Analysis highlighted inoculum as the key factor influencing these parameters. Following this, fermentation was scaled up in 6.5 L bioreactors operating under static and stirred conditions. Monitoring physicochemical properties, antioxidant capacity, and volatile compounds revealed the impact of agitation on fermentation, with the kombucha obtained by static cultivation presenting higher biological activity. Eleven volatile compounds were identified, including carboxylic acids, terpenes, esters, alcohols, and phenols. Notably, α-terpinolene, dodecanoic acid, and 2,4-di-tert-butylphenol, found in kombucha, exhibit antioxidant properties linked to health benefits. Differences in volatile compound profiles were observed between static and stirred processes. This study concluded that kombucha maintains its physicochemical characteristics and bioactivity during scale-up, contributing to a better understanding of large-scale production. It also suggests stirred cultivation as an alternative for kombucha production.

Influência das condições de torra e do processo extrativo em blends de café / Influence of roast conditions and extractive process in coffee blends

The objective of this work was to determine the physicochemical characteristics of coffee beverages prepared with Coffea arabica beans produced at different altitudes in the municipality of Taquaritinga do Norte, in the state of Pernambuco, Brazil. Eight coffee bean samples, obtained from five different producers, were analyzed in a completely randomized design, with three replicates. The evaluated variables were: total acidity, pH, electrical conductivity, total dissolved solids, extraction percentage, reducing sugars, and caffeine content. The data were subjected to the analysis of variance, Tukey’s mean test, and agglomerative hierarchical clustering. The results showed total acidity from 0.39 to 3.05 mL^-1 NaOH, pH from 5.30 to 4.80, electrical conductivity from 2.79 to 3.24 µS cm^-1, total dissolved solids from 2.00 to 2.56 °Brix, extraction percentage from 18.14 to 27.24%, reducing sugars from 0.28 to 0.40%, and caffeine content from 0.50 to 2.18%. Through agglomerative hierarchical clustering, two groups of samples were discriminated based on the evaluated physicochemical parameters. Altitude is a common aspect of the samples of a same group, defining different characteristics of coffee beverages in Taquaritinga do Norte.

The species Coffea arabica and Coffea canephora, arabica and conilon, respectively, are the most widely used by coffee roasters worldwide. This work aimed to trace the physicochemical profile of blends made with Arabica and Conilon coffee subjected to different roasting conditions. Eleven blends were prepared, according to a complete 2³ factorial design, in different concentrations of arabica and conilon, temperature and roasting time. The blends were roasted, ground, physico chemically analyzed and the results submitted to statistical analysis. All blends classified as fine roast, showed low mass loss and good yield. Density was higher for blends with higher concentration of conilon. pH and color were the parameters most influenced by the degree of roasting. The values of moisture, total soluble solids, aqueous extract, caffeine, and lipids were in accordance with what is required by legislation. It was observed that the experiments elaborated with 31.25% arabica coffee, roasted at 170 ºC for 12 min, showed good results, in relation to the visual and physicochemical aspects, indicating that it can be a standard of blend adopted by the roasting industries. of coffee.

O Brasil destaca-se como o maior produtor mundial de frutas cítricas e de suco processado, respondendo por mais de 30% da produção global. As cascas de frutos cítricos podem representar entre 50% e 60% da massa total da fruta, sendo normalmente descartadas no processamento, embora possam ser convertidas em produtos de maior valor agregado ou utilizadas para fortificar alimentos e melhorar seu perfil nutricional. O objetivo deste trabalho foi caracterizar físico-quimicamente e avaliar o potencial antioxidante e fenólico de farinhas obtidas das cascas das seguintes espécies de Citrus: Lima ácida Tahiti (Citrus latifolia Tanaka), Limão Galego (Citrus aurantifolia), Laranja Pêra (Citrus sinensis), Tangerina Mimo (Citrus reticulata), Tangerina Ponkan (Citrus reticulata) e Pomelo (Citrus grandis), visando avaliar seu potencial de aproveitamento como alimento funcional. As farinhas foram obtidas após secagem (55 °C/24 h) e moagem das cascas. Realizou-se a composição centesimal e caracterização físico-química, incluindo umidade, atividade de água, pH, acidez total titulável, sólidos solúveis totais, açúcares redutores, cinzas, proteínas, carboidratos, condutividade elétrica, compostos fenólicos totais e atividade antioxidante (ABTS e DPPH). As análises evidenciaram baixa atividade de água e composição nutricional relevante, com destaque para o elevado teor de carboidratos estruturais e a presença significativa de compostos bioativos. As farinhas de cascas de Citrus podem ser empregadas como ingredientes enriquecedores e fontes naturais de compostos bioativos, configurando estratégia promissora para a inovação na indústria de alimentos, conciliando segurança alimentar, sustentabil