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Plant growth promoting bacteria and nitrogen-fixing bacteria (NFB) used for crop inoculation have important biotechnological potential as a sustainable fertilization tool. However, the main limitation of this technology is the low inoculum survival rate under field conditions. Microencapsulation of bacterial cells in polymer matrices provides a controlled release and greater protection against environmental conditions. In this context, the aim of this study was to isolate and characterize putative NFB associated with lupin nodules and to evaluate their microencapsulation by spray drying. For this purpose, 21 putative NFB were isolated from lupin nodules and characterized (16S rRNA genes). Microencapsulation of bacterial cells by spray drying was studied using a mixture of sodium alginate:maltodextrin at different ratios (0:15, 1:14, 2:13) and concentrations (15 and 30% solids) as the wall material. The microcapsules were observed under scanning electron microscopy to verify their suitable morphology. Results showed the association between lupin nodules of diverse known NFB and nodule-forming bacteria belonging to Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria and Bacteroidetes. In microencapsulation assays, the 1:14 ratio of sodium alginate:maltodextrin (15% solids) showed the highest cell survival rate (79%), with a microcapsule yield of 27% and spherical microcapsules of 5-50 µm in diameter. In conclusion, diverse putative NFB genera and nodule-forming bacteria are associated with the nodules of lupine plants grown in soils in southern Chile, and their microencapsulation by spray drying using sodium alginate:maltodextrin represents a scalable process to generate a biofertilizer as an alternative to traditional nitrogen fertilization.

QUALIDADE DE FRUTOS PROCESSADOS ARTESANALMENTE DE AÇAÍ (Euterpe oleraceaMART QUALITY OF FRUITS MANUALLY PROCESSED OF AÇAÍ (Euterpe oleracea MART.) and BACABA (Oenocarpus bacaba MART.)ABSTRACT -The fruits of açaizeiro (Euterpe oleracea Mart.) and of bacabeira (Oenocarpus bacaba Mart), two native tropical palms and socio-economically important for the Amazonian states, are utilized, almost in its entirety, in the production of processed pulp on agricultural family systems. In this sense, the present study aimed to the evaluation of physical, chemical, physic-chemical and functional quality of processed pulps of açai and bacaba. The fruits were harvested in private rural properties in the county of Cantá/Roraima (bacaba) and Boa Vista/Roraima (açaí). For the preparing of the experiment, the processed pulps were stored in small containers of polyethylene terephthalate (PET) transparent and cover (same material), with capacity of 145ml and, refrigerated at 3 ± 0.2 °C and 45% RH for 5 days. It was analyzed the follow parameters: pH, titratable acidity (TA), soluble solids (SS), ratio (SS/TA), total and reducing sugars, total and soluble pectin, and the content of anthocyanins and total phenolics. At the end, for the açaí pulps, taking into account the limits set by Standard Identity and Quality (PIQ), only the TA parameter presented itself outside the normative instruction. However, the lack of standards for the bacaba pulps prevented such a comparison. Regarding the total content of pectin, it is possible concluded that both pulps presented low concentrations of this component, and aren't suitable for producing jams and jellies without the addition of gelling agents. The total phenolic contents and anthocyanins, in both pulps, although decreasing with the refrigerated storage time, show reasonable concentrations in comparison to other foods with functional appeal.

-This study evaluated the post-acidification, stability of anthocyanins and antioxidant activity in açai yogurts and fermented milks for 28 days of cold storage. For the determination of post-acidification and stability of the functional properties of açai yogurt (IA) and fermented milks (LFA), products stored at 4°C were evaluated on day 0 and every 7 days for pH, titratable acidity in lactic acid, instrumental color, anthocyanins and antioxidant activity by the DPPH free radical method. Acidification of both food matrixes was more evident between days 0 and 7 of evaluation. IA presented reduction in parameter L *, while chromaticity a * and b * of IA and LFA increased as the Açai pulp content increased; however, considering the evaluation period, it was found increase in L * and b * relating to anthocyanin degradation. Anthocyanins, as well as the antioxidant activity of IA and LFA, showed an increase in their values as the pulp content increased, but their concentrations reduced at the end of the storage period. IA and LFA can be considered excellent sources of antioxidants, being alternative to individuals not used to the consumption of fruits and vegetables. Index terms: Dairy products, functional foods, native fruits, Amazon. ESTUDO DE PÓS-ACIDIFICAÇÃO E AVALIAÇÃO DA ESTABILIDADE DE ANTOCIANINAS E ATIVIDADE ANTIOXIDANTE EM IOGURTES E LEITES FERMENTADOS DE AÇAÍ (Euterpe oleracea Mart.)RESUMO -Neste trabalho foi avaliada a pós-acidificação, a estabilidade das antocianinas e da atividade antioxidante em iogurtes e leites fermentados de açaí durante 28 dias de armazenamento refrigerado. Para determinação da pós-acidificação, assim como da estabilidade das propriedades funcionais dos iogurtes (IA) e leites fermentados (LFA) de açaí, os produtos armazenados a 4 ºC, foram avaliados no dia 0 e a cada 7 dias, quanto ao pH, acidez titulável em ácido lático, cor instrumental, antocianinas e atividade antioxidante pelo método do radical livre DPPH. A acidificação de ambas as matrizes alimentares foram mais evidentes entre os dias 0 e 7 de avaliação. Os IA apesentaram redução no parâmetro L*, enquanto que as cromaticidade a* e b* dos IA e LFA aumentaram seus valores, à medida que o teor de polpa de açaí foi aumentado, entretanto considerando o período de avaliação, verificou-se aumento de L* e b* relacionando-se as degradações nas antocianinas. As antocianinas, assim como a atividade antioxidante dos IA e LFA mostraram aumento em seus valores conforme os teores de polpa foram aumentados, porém reduziram suas concentrações ao fim do período de armazenamento. Os IA e LFA, podem ser considerados excelentes fontes de substâncias antioxidantes, sendo alternativa a indivíduos não habituados ao consumo de frutas e legumes. Termos para indexação: Produtos lácteos, alimentos funcionais, frutos nativos, Amazônia.

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The açaí (Euterpe oleracea Mart.) is an Amazonian fruit that is widely consumed in Brazil and around the world, particularly due to its large number of bioactive compounds. In order to verify the bioactive characteristics of açaí in popular consumer products, the aim of this study was to test the increasing function of açaí pulp (bioactive compounds and antioxidant activity) in the production of coconut candy. The treatments consisted of four formulations of coconut candy (C): with no açaí pulp (CA0), with 10% açaí pulp (CA10), with 20% açaí pulp (CA20) and with 30% açaí pulp (CA30), in addition to the sugar, grated coconut, gum agar, citric acid and water that are part of the standard formulation of each treatment. The experimental design was completely randomised with three replications. The following analyses were carried out: total sugars, lipids, proteins, moisture, calorific value, phenolic compounds, anthocyanins, and antioxidant activity using the DPPH method. The increasing concentrations of açaí in the formulations significantly increased the total sugar and lipid concentrations, moisture, and calorific value. The anthocyanin concentration increased linearly with the increase in pulp concentration. The coconut candy from formulation CA20 showed the greatest antioxidant activity between the proposed formulations. The formulations had no effect on the levels of phenolic compounds. The anthocyanin content differed statistically between formulations, with the highest values seen in formulation CA30. Formulations CA20 and CA30 are sources of bioactive components.

ResumoOs produtos lácteos fermentados estão entre os principais produtos alvo de estudos que buscam elaborar alimentos probióticos que agreguem benefícios para saúde. Nesse sentido, o objetivo deste trabalho foi elaborar leites fermentados com camu-camu e suplementados com Bifidobacterium (BB-12) e Lactobacillus acidophilus (LA-5) e avaliar a viabilidade destes microrganismos durante 28 dias de armazenamento refrigerado. Os frutos de camu-camu foram coletados em plantas localizadas no Rio Urubu, Bonfim-RR. Os frutos foram encaminhados ao LTPA/EAGRO, sendo adicionado100 mL de água mineral e triturados em liquidificador para obtenção da polpa, que em seguida foi armazenada em embalagens plásticas com capacidade de 100 mL e congelada em freezer a -18 ºC. Para obtenção dos leites fermentados com camu-camu utilizou-se duas formulações: Leite fermentado Reduzido em Calorias (LFRC) e Leite Fermentado Integral (LFI), sendo elaborados com leite UHT desnatado e integral respectivamente, 10% de açúcar, 0,3% de sorbato de potássio e 0,08% de culturas probióticas presentes no fermento Bio Rich® da empresa Chr Hansen. Em seguida, foi adicionada polpa de camu-camu nas concentrações de 5%, 10%, 15% (p/p) sendo reservada amostra sem adição de polpa para constituir o tratamento controle. As duas formulações propostas LFRC e LFI atenderam a legislação quanto às contagens de bactérias probióticas LA-5, sendo classificados como produtos probióticos, apresentando contagem acima de 6 Log UFC g -1 , durante 14 dias de avaliação. O leite UHT desnatado, mostrou maior potencial probiótico, concluindo que houve influência positiva da redução no percentual de gordura do leite para o crescimento dos Lactobacillus acidophilus.