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Artigo Bati Butter as a potential substrate for lipase production by Aspergillus terreus NRRL-255(Foods, 2023-01-27) Passos, Thais Souza; Assis, Cristiane Fernandes de; Barros, Karen dos Santos; Jácome, Millena Cristiane de Medeiros Bezerra; Azevedo, Wendell Medeiros de; Ramalho, Adriana Margarida Zanbotto; Santos, Everaldo Silvino dos; Sousa Junior, Francisco Canindé de; Damasceno, Karla Suzanne Florentino da Silva Chaves; https://orcid.org/0000-0003-2054-1544; https://orcid.org/0000-0001-7595-5395; https://orcid.org/0000-0003-2042-4348; https://orcid.org/0000-0001-6884-1023This study evaluated bati butter (Ouratea parviflora) as a substrate for lipase productionby solid-state fermentation (SSF) using Aspergillus terreus NRRL-255. A gas chromatograph with a flame ionization detector determined the bati butter fatty acid profile. Lipase production and spore count were optimized using a 3^2 experimental design and evaluated using the response surface methodology. Moreover, the crude enzyme extract was evaluated against different pH, temperature, and activating and inhibitors reagents. Regarding the fatty acids identified, long-chain accounted for 78.60% of the total lipids. The highest lipase production was obtained at 35 ◦C and 120 h of fermentation, yielding 216.9 U g−1 . Crude enzyme extract presented more significant activity at 37 ◦C and pH 9. β-Mercaptoethanol increased the enzyme activity (113.80%), while sodium dodecyl sulfate inactivated the enzyme. Therefore, bati butter proved to be a potential substrate capable of inducing lipase production by solid-state fermentationArtigo Effects of different structure-directing agents (SDA) in MCM-41 on the adsorption of CO2(Journal of Porous Materials, 2014) Melo, Marcus Antonio de Freitas; Costa, C. C.; Melo, Dulce Maria de Araújo; Mendoza, M. E.; Nascimento, J. C.; Andrade, J. M.; Barros, J. M. F.CO2 capturing technologies have attracted significant attention in order to limit emissions and reduce their negative effect on the environment. Mesoporous silica materials (MCM-41) are easily recyclable, affordable, and thermally and mechanically stable, providing added benefits in CO2 capture. However, further studies are necessary to characterize the effects of MCM-41 pore size, adsorption temperature and surface silylation on CO2 adsorption efficiency. In this work, mesoporous silica is synthesized using alkyltrimethylammonium bromide with different chain lengths (CnH2n ? 1 N(CH3)3Br, n = 14, 16 and 18) as structure-directing agents, and the adsorption capacity of CO2 on TTMCM-41 (C17H38NBr), CTMCM-41 (C19H42 NBr), DTMCM-41(C21H46NBr) samples was measured gravimetrically at room temperature and pressure up to 40 bar. The silica structures were characterized by X-ray diffraction (XRD), nitrogen adsorption/desorption, Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy and transmission electron microscopy (TEM). The XRD, N2 adsorption– desorption and TEM measurements indicated the presence of a well-ordered hexagonal array with uniform mesostructures. The mesoporous silica obtained, denoted as TTMCM-41, CTMCM-41 and DTMCM-41, had distinct physical properties, such as BET surface area, hexagonal unit cell, pore volume, pore diameter and pore wall thickness. CTMCM-41 exhibited an adsorption capacity (0.58 g CO2/g adsorbent) of more than DTMCM-41 (0.48 g CO2/g adsorbent) and TTMCM-41 (0.42 g CO2/g adsorbent). The results suggest that CTMCM-41 can be a better mesoporous adsorbent for CO2 adsorption.Artigo Pyrolysis kinetics of elephant grass pretreated biomasses(Springer, 2014) Melo, Marcus Antonio de Freitas; Braga, Renata Martins; Costa, Tiago Roberto da; Freitas, Julio C. O.; Barros, Joana Maria de Farias; Melo, Dulce Maria de AraújoThe Elephant Grass (Pennisetum purpureum Schum) was pretreated by two independent processes, through washing with hot water (W-EG) and acid solution (AW-EG) to improve its energy properties to apply it in a thermochemical process conversion into fuel. The biomasses were analyzed by proximate and ultimate analysis; and the pyrolysis kinetics, before and after pretreatments, were evaluated by the apparent activation energy (Ea) for decomposition in the temperature range of greater volatile matter through the Model-free kinetics using thermogravimetric analysis data. The kinetics of the microcrystalline cellulose Avicel PH-101 was performed to evaluate the Ea result of pure cellulose. The pretreatments were efficient in increasing the volatile matter and heating value, decreasing moisture and ash content, and improving its energetic power to the application in fast pyrolysis process for bio-oil production. The TG results have shown that the reduction in ash content facilitates the pyrolysis process, increasing the volatile matter and decreasing the apparent activation energy equired to biomasses degradation, due to less diffusional resistances to heat and mass transfer of W-EG and AW-EG. The Avicel PH-101 showed the highest value of apparent activated energy (Ea = 276.2 kJ mol-1) which could be explained by its crystallinity, suggesting that crystalline cellulose regions are less accessible to heat diffusion than amorphous regions, requiring more energy to its degradation.Artigo Síntese e caracterização de materiais mesoporosos modificados com níquel para a captura de CO2(Cerâmica - Associação Brasileira de Cerâmica, 2014) Melo, Marcus Antonio de Freitas; Nascimento, Alexsandra Rodrigues do; Figueredo, Gilvan Pereira de; Rodrigues, G.; Souza, Marcelo José Barros de; Melo, Dulce Maria de AraújoMateriais mesoporosos tipo SBA-15 e MCM-48 foram sintetizados com sucesso pelo método hidrotérmico e impregnados com níquel nas proporções de 5-20 peso% visando à captura de CO2. Os materiais obtidos foram caracterizados por meio de análise por difração de raios X, adsorção de N2 e microscopia eletrônica de varredura. Testes de captura de CO2 foram conduzidos em pressões entre 100 e 4000 KPa à temperatura constante de 298 K e revelaram que as capacidades de adsorção variam significativamente com as propriedades texturais dos materiais com diferentes teores de níquel, atingindo valores máximos de 14,89 e 9,97 mmol g-1 para MCM-48 e SBA-15, respectivamenteArtigo Kinetic study of CTMA+ removal from the pores of the Ti-MCM-41 molecular sieve(Journal of Thermal Analysis and Calorimetry, 2014) Melo, Marcus Antonio de Freitas; Fontes, Maria do Socorro Braga; Melo, Dulce Maria de Araújo; Barros, Joana Maria de Farias; Braga, Renata Martins; Fontes, Vilsinéia dos AnjosThermogravimetry analysis was used to study the thermal decomposition of Ti-MCM-41 to determine the best calcination conditions. Ti-MCM-41 molecular sieve was synthesized using a hydrothermal route in which Ti ions were incorporated into the pore channels of MCM-41 starting from a hydrogel method according to the following molar composition: 1.00 CTMABr:4.00 SiO2:X TiO2:1.00 Na2O:200.00 H2O. Physicochemical properties of samples were investigated using XRD, FTIR, and N2 adsorption– desorption to confirm the incorporation of TiO2 nanoparticles inside of MCM-41 mesoporous without destroying its structure. The high temperatures facilitate the rapid removal of the surfactant; however, it caused destruction of the MCM-41 structure by breaking the bonds of the silica tetrahedral structure. The procedures to obtain the apparent activation energies of CTMABr decomposition were based on the kinetic model proposed by Flynn-Wall using thermal analysis of data performed with heating rates 5, 10, and 20 C min-1Artigo Dried camu-camu (Myrciaria dubia H. B. K. McVaugh) industrial residue: a bioactive-rich Amazonian powder with functional attributes(Elsevier, 2014-08) Azevedo, Juliana Chrís Silva de; Fujita, Alice; Oliveira, Edson Leandro de; Genovese, Maria Inês; Correia, Roberta Targino PintoCamu-camu is a tropical Amazonian fruit, extensively processed into fruit pulp and other derivatives. This work investigates the fresh and dried (hot air dried and freeze dried) camu-camu depulping residue in regard to its physicochemical characteristics, bioactive content, in vitro antidiabetic potential and antimicrobial activities. The phenolic content of fresh residue (FR), hot air dried residue at 50 °C (HAD50), hot air dried residue at 80 °C (HAD80) and freeze dried residue (FD) were 3738.0, 1843.6, 1349.4 and 2160.2 mg GAE/100 g DW, respectively. Important flavonoids were identified (quercetin, myricetin, and catechin), besides high amount of ellagic acid (18.9 mg/100 g DW for the fresh residue), and for the first time in literature, the presence of syringic acid (3.1 to 7.0 mg/100 g DW) in the camu-camu residue was shown. The Minimum Inhibitory Concentration against Staphylococcus aureus ranged from 0.3125 to 0.625 mg/mL for freeze dried and hot air dried camu-camu residues. Moderate in vitro alpha-amylase and potent alpha-glucosidase inhibitory activities were also observed for all extracts. This paper presents the dried camu-camu residue as a natural powder with bioactive and functional properties.Artigo Structural characterisation and cell viability of a spray dried probiotic yoghurt produced with goats' milk and Bifidobacterium animalis subsp. lactis (BI-07)(Elsevier, 2014-11) Medeiros, Adja Cristina Lira de; Thomazini, Marcelo; Urbano, Alexandre; Correia, Roberta Targino Pinto; Trindade, Carmen SílviaThe aim of this study was to obtain and characterise probiotic yoghurt powders with respect to their physico-chemical properties and also to evaluate the viability of probiotic microorganisms. The yoghurts were prepared by using goat milk inoculated by yoghurt cultures and the probiotic strain Bifidobacterium animalis subsp. lactis (BI-07). In the spray drying process, the temperature of inlet air (130, 150 and 170 °C) and the concentration of maltodextrin (10 and 20%) were varied. The dried goat yoghurts with added probiotics had low moisture and aw values, solubility between 68.2 and 81.1% and were highly hygroscopic. The yoghurt powder particles showed an average size from 12.7 ± 5.50 μm to 23.4 ± 0.84 μm, amorphous state, round shape and glass transition temperature varying from 42 to 45 °C. The use of drying temperature 130 °C and addition of 10% (w/w) maltodextrin produced the best probiotic viability during storage.Artigo Potentially probiotic ice cream from goat's milk: characterization and cell viability during processing, storage and simulated gastrointestinal conditions(Elsevier, 2015-06) Silva, Priscilla Diniz Lima da; Bezerra, Maria de Fátima; Santos, Karina Maria Olbrich dos; Correia, Roberta Targino PintoIn this work, the physicochemical characteristics, meltdown behavior and sensory properties of goat's milk ice cream produced with and without the probiotic bacteria Bifidobacterium animalis subsp. lactis BLC1 were analyzed. The ice cream with added B. animalis was further evaluated in regard to the probiotic viability during processing, frozen storage, and simulated gastrointestinal conditions. Results showed that the addition of B. animalis decreased the pH (p < 0.05), but it had no effect on physicochemical properties, including overrun and melting behavior of ice cream from goat's milk (p > 0.05). After 120 days of frozen storage, a survival rate of 84.7% was registered. With regard to cell viability during gastrointestinal conditions, the exposure to bile and pancreatin resulted in the decline of 3.82 log cycles in ice cream samples previously stored at −18 °C for 120 days. Overall, the goat's milk ice cream with B. animalis received good sensory scores and satisfactory probiotic viability (6–7 log CFU/g) was maintained throughout the 120 days of frozen storage. Therefore, this research shows that goat's milk ice cream is an adequate delivery vehicle for the probiotic bacteria B. animalis.Artigo Caracterização físico-mecânica e ambiental de cerâmica estrutural com imobilização do íon manganês(Cerâmica Industrial, 2013) Melo, Marcus Antonio de Freitas; Câmara, Ana Paula Costa; Medeiros, Leonardo Coutinho de; Macedo, Daniel Araújo de; Galdino, José Nildo; Melo, Dulce Maria de AraújoNeste trabalho a adição do íon manganês bivalente a uma massa argilosa do Estado do Rio Grande do Norte foi estudada a fim de avaliar a viabilidade das peças sinterizadas para uso em cerâmica estrutural. A matéria-prima cerâmica foi caracterizada por análise química (FRX) e difratometria de raios-X (DRX). Assim, o íon metálico foi adicionado na forma de soluções aquosas nas concentrações de 100, 150 e 200 mg/L. Os corpos de prova obtidos por extrusão e sinterizados entre 850 e 1150 °C foram caracterizados por ensaios de solubilidade. As propriedades tecnológicas avaliadas foram: retração linear de queima, absorção de água, porosidade aparente, massa específica aparente e tensão de ruptura à flexão em três pontos. Propriedades como porosidade aparente e absorção de água não apresentaram variações significativas em função da concentração do íon manganês. Por outro lado, a tensão de ruptura à flexão cresce com o aumento da temperatura independente da concentração do íon. Quanto aos resultados, foi possível identificar que a cerâmica com imobilização do íon manganês nas concentrações entre 100 e 200 mg/L é adequada para a fabricação de diversos produtos cerâmicos, tais como tijolo maciço e revestimento semi-poroso, sem oferecer risco ao meio ambienteArtigo Impact of spouted bed drying on bioactive compounds, antimicrobial and antioxidant activities of commercial frozen pulp of camu-camu (Myrciaria dubia Mc. Vaugh)(Elsevier, 2013-11) Fujita, Alice; Borges, Kátia; Correia, Roberta Targino Pinto; Franco, Bernadette Dora Gombossy de Melo; Genovese, Maria InésCamu-camu (Myrciaria dubia Mc. Vaugh) has promising perspectives for agro industrial purposes mainly due to the functional potential. This works deals with the impact of spouted bed drying on bioactive compounds, antioxidant and antimicrobial activities, having the fresh and freeze-dried fruit pulp as references. Commercial camu-camu pulp was spouted bed dried at selected temperatures with different maltodextrin concentrations (carrier agent). The fruit powders were compared in relation to color, in vitro antioxidant capacity, total phenolics, ascorbic acid and proanthocyanidin contents. The spouted bed drying of the pulp led to significant losses, in the order ascorbic acid (45–64%) > total phenolics (33–42%) > proanthocyanidins (16–18%), and freeze-drying better preserved antioxidant capacity (74 to 87%) compared to spouted bed drying (29 to 78%). Freeze-dried powder was classified as active, and spouted bed powders as partially active, against S. aureus. Despite of losses caused by drying, camu-camu powders still represent excellent sources of bioactive compounds with great potential for use as new bioactive ingredients.Artigo Caracterização físico-química e bioativa do Figo-da-Índia (Opuntia ficus-indica) e farinha de Algaroba (Prosopis juliflora) e avaliação sensorial de produtos derivados(Alimentos e Nutrição, 2013) Souza, Rosane Liége Alves de; Correia, Roberta Targino PintoObjectives: To determine the physicochemical properties of and investigate the bioactive substances, such as phenolic compounds and betalains, and antioxidant activity in Opuntia fruit (Indian fig) and Prosopis juliflora (mesquite) bean-pod flour, in order to assess their potential as functional food ingredients. Material and Methods: The total phenolic content was determined by the Folin- Ciocalteu method, betalain pigments were measured by spectrophotometry and the antioxidant activity by the DPPH radical-scavenging method. Juice blends, made by mixing the local cajá (Spondias mombin or 'hog plum') fruit and Indian fig pulp, were subjected to sensory evaluation by Quantitative Descriptive Analysis. Cereal bars prepared with and without mesquite flour were compared by a sensory discrimination method. Results: Low acidity, high sugar and considerable phenolic and betalain contents and antioxidant activity were found in the Opuntia fruits. Prosopis flour had high levels of protein, sugar and fiber. The sensory attributes that best described Opuntia-cajá blends were sweetness, acidity, yellow-orange color, body, turbidity and distinctive cajá flavor. Regarding cereal bars made with and without Prosopis flour, texture was the only sensory attribute perceived as different (p < 0.05) during the sensory discrimination analysis. Conclusion: This study shows that the mixed fruit pulp and mesquite flour are satisfactory as ingredients in food formulations. The bioactive and technological potential of these semiarid underexploited species of fruit and legume flour was also demonstrated.Artigo Phenolic content, antioxidant activity and antiamylolytic activity of extracts obtained from bioprocessed pineapple and guava wastes(Brazilian Journal of Chemical Engineering, 2012-03) Sousa, B. A.; Correia, Roberta Targino PintoThe relationship between phenolic content, antioxidant and antiamylolytic activities was investigated in Rhizopus oligosporus-mediated solid-state bioprocessing of pineapple and guava residues. Two different treatments of fruit residues mixed with soy flour (5g of soy flour and 5g of fruit residue; 1g of soy flour and 9g of fruit residue) were inoculated and incubated at 22ºC. Phenol rich extracts (non-concentrated and concentrated 10-fold by boiling) from day 2 and 10 were tested for their ability to inhibit alpha-amylase. In order to correlate the enzymatic inhibition with phenolic-linked antioxidant activity of the extracts, samples were evaluated for total phenolic content and free radical scavenging. Alpha-amylase inhibition was observed for all extracts, concentrated or not, with values ranging from 10.91% to 100% (complete inhibition). A direct correlation between the total phenolic content or the free radical scavenging activity and alpha-amylase inhibition was not found, demonstrating that such an inhibition could be caused by the presence of specific compounds, phenolic or not, rather than by the actual concentration of overall fruit phenolics.Artigo Kinetic study of template removal of MCM-41 derived from rice husk ash(Journal of Thermal Analysis and Calorimetry, 2013) Melo, Marcus Antonio de Freitas; Braga, Renata Martins Braga; Barros, Joana Maria de Farias Barros; Melo, Dulce Maria de Araújo; Aquino, Flávia de Medeiros; Freitas, Júlio Cézar de Oliveira; Santiago, Rodrigo CésarMolecular sieves MCM-41 were synthesized from rice husk ash (RHA) as alternative sources of silica, called RHA MCM-41. The material was synthesized by a hydrothermal method from a gel with the molar composition 1.00 CTMABr:4.00 SiO2:1.00 Na2O:200.00 H2O at 100 C for 120 h with pH correction. The cetyltrimethyl- ammonium bromide (CTMABr) was used as a structure template. The material was characterized by X-ray powder diffraction, FTIR, TG/DTG, and surface area determination by the BET method. The kinetics models proposed by Ozawa, Flynn–Wall, and Vyazovkin were used to determine the apparent activation energy for CTMA? species decomposition from the pores of MCM-41 material. The results were compared with those obtained from the MCM-41 synthesized with silica gel. The synthesized material had specific surface area, size, and pore volume as specified by mesoporous materials developed from conventional sources of silica.Artigo Biotechnological reuse of fruit residues as a rational strategy for agro-industrial resources(Journal of Technology Management & Innovation, 2010-08) Sousa, Bruno Alexandre de Araújo; Correia, Roberta Targino PintoBrazil, one of the largest agricultural producers in the world, has managed in recent years to significantly improve its production. However, in response to this advance in the agro-industrial sector, the generation of agro-industrial residues or sub-products has also increased, and its improper disposal may have a strong environmental impact, in addition to causing losses of raw materials and energy. In this context, the use of these residues as substrates for the production of high value-added compounds using semi-solid fermentation has been studied. Thus, the aim of this study was the physical-chemical characterization of pineapple and guava residues and their potential reuse in semi-solid cultivation. The results show that both residues are sources of bio-usable nutrients after a number of operational parameters of the bioprocess of choice are adjusted.Artigo Posicionamento do consumidor frente ao consumo de leite de cabra e seus derivados na cidade de Natal-RN(Revista do Instituto de Laticínios Cândido Tostes, 2009) Correia, Roberta Targino Pinto; Borges, Kátia CristinaA Região Nordeste têm concentrado ao longo da história grande parte do rebanho caprino brasileiro. É uma atividade econômica de grande importância para o sertanejo, já que serve como fonte de renda, subsistência e fator de fixação do homem no interior. Apesar de todo o potencial funcional e nutritivo já reconhecido desse tipo de leite, a caprinocultura leiteira ainda se caracteriza por ser uma atividade desenvolvida de forma empírica e extensiva e com baixos níveis de tecnologia, além de dificuldades no setor produtivo que incluem entraves na comercialização e pequeno número de produtos derivados disponíveis no mercado. A presente pesquisa tem o objetivo de avaliar o posicionamento do consumidor em Natal-RN quanto ao possível consumo do leite de cabra e derivados, tendo em vista a quase inexistência de trabalhos abordando esse aspecto. O trabalho tem caráter exploratório e descritivo, tomando como base as respostas obtidas de 400 indivíduos abordados na capital potiguar através de questionário estruturado composto por 15 questões sobre conhecimento do mercado, conhecimento nutricional, atitude e comportamento. Os resultados apontam para o desconhecimento sobre a qualidade nutricional do leite de cabra por parte dos entrevistados incluídos na pesquisa. Indicam também que os aspectos sensoriais odor e sabor, além da confiabilidade no produto, estão entre os elementos considerados na decisão de não comprar o leite caprino, ao passo que o potencial benefício á saúde é apontado como um dos parâmetros importantes para a aquisição do leite caprino.Artigo Iogurte de leite de búfala sabor cajá (Spondias lutea L.): caracterização físico-química e aceitação sensorial entre indivíduos de 11 a 16 anos.(Alimentos e Nutrição Araraquara, 2009) Borges, Kátia Cristina; Medeiros, Adja Cristina Lira de; Correia, Roberta Targino PintoO presente estudo teve como objetivo caracterizar físico-quimica e sensorialmente o iogurte batido elaborado com leite bubalino acrescido de calda de cajá e compará-lo com o tradicional iogurte bovino. Foram elaborados dois grupos experimentais: IB (iogurte elaborado com leite de búfala) e IV (iogurte elaborado com leite de vaca), os quais receberam calda de cajá na proporção 15% (p/p). Os dois grupos de iogurtes foram analisados quanto ao pH, acidez (ºDornic), sólidos totais, cinzas, proteína, gordura, açúcares redutores e redutores totais (%). O painel sensorial composto por 90 alunos com idades entre 11 e 16 anos de uma escola pública avaliou os atributos aparência, aroma, consistência e sabor utilizando escala hedônica de nove pontos. Os resultados mostraram que houve diferença estatística (p<0,05) entre os grupos IB e IV, sobretudo para o teor de sólidos totais (23,86 e 15,68% IB e IV, respectivamente) e proteína (5,50 e 4,77% IB e IV, respectivamente). O iogurte bubalino apresentou escore sensorial superior (p<0,05) em todos os atributos sensoriais analisados. Conclui-se, dessa forma, que o iogurte bubalino apresenta diferenças marcantes do ponto de vista físico-químico e sensorial em relação ao iogurte bovino.Artigo Síntese e caracterização de espinélios à base de ferritas com gelatina como agente direcionador(Cerâmica, 2012) Melo, Marcus Antonio de Freitas; Costa, Asenete Frutuoso; Pimentel, Patrícia Mendonça; Melo, Dulce Maria de Araújo; Aquino, Flávia de MedeirosAs ferritas com estrutura tipo espinélio compreendem um grupo de materiais magnéticos muito bem estabelecidos. Contudo, melhoramentos e inovações continuam acontecendo visando novas aplicações e otimização das técnicas de preparação. Dentre os materiais com estrutura espinélio, as ferritas se destacam por possuírem ampla importância tecnológica na área de materiais, com aplicabilidades em sensores de umidade e de oxigênio, materiais de microondas, pigmentos, materiais magnéticos e elétricos, catálise de hidrogenação, fi lmes fi nos, revestimentos cerâmicos, dentre outros. Neste trabalho espinélios tipo CuFe2O4 e CuFeCr2O4 foram sintetizadas usando gelatina como agente direcionador, com a finalidade de produzir partículas nanométricas e homogêneas através de um método simples, rápido e economicamente viável. Os pós foram caracterizados por difração de raios X, espectroscopia de absorção no infravermelho e microscopia eletrônica de varredura. Os resultados confi rmaram a viabilidade da rota de síntese utilizadaArtigo Gelatin synthesis of CuFe2O4 and CuFeCrO4 ceramic pigments(Materials Letters, 2013) Melo, Marcus Antonio de Freitas; Costa, Asenete Frutuoso; Pimentel, Patrícia Mendonça; Aquino, Flávia de Medeiros; Melo, Dulce Maria de Araújo; Santos, Ieda Maria Garcia dosIn the present study, CuFe2O4 and CuFeCrO4 spinels were synthesized using a method, which makes use of gelatin as an organic precursor in order to assess the applicability as ceramic pigments. Powders resulting from the synthesis process were calcined between 500 and 900 °C and characterized by X-ray diffraction (XRD), infrared spectroscopy, scanning electron microscopy (SEM), UV–vis spectroscopy and Colorimetry analysis. Results showed brown color for the CuFeCrO4 spinel and darker colors, from brown to black, for CuFe2O4. This is an interesting finding due to the great importance of black pigments in the ceramic industryArtigo Iogurte de leite de búfala com calda de umbu(Revista Higiene Alimentar, 2009-09) Correia, Roberta Targino Pinto; Medeiros, Adja Cristina Lira de; Borges, Kátia CristinaO presente trabalho objetiva avaliar a elaboração do iogurte produzido com leite bubalino e acrescido de calda de umbu, visando obter produto de elevada qualidade e aceitação sensorial. O produto foi comparado com o tradicional iogurte bovino através de determinações físico-químicas e sensoriais. A calda foi acrescida na proporção 15% (p/p) em relação à base láctea, sendo metade misturada ao iogurte e a outra metade no fundo do copo. As determinações de pH, acidez (ºDornic), sólidos totais (%), cinzas (%), proteína (%), gordura (%), açúcares redutores (%) e açúcares redutores totais (%) foram realizados nos iogurtes, e para a calda, pH, acidez e atividade de água. As análises foram realizadas segundo Normas do Instituto Adolfo Lutz (1985) e os teores de açúcares redutores (AR) e redutores totais (ART) dosados pelo método DNS (MILLER, 1959). A análise sensorial utilizou a escala hedônica com 30 provadores não-treinados para os atributos aparência, odor, consistência e sabor. Os leites de vaca e búfala alcançaram, respectivamente, pH 6,63 e 6,77. Foram observadas diferenças estatisticamente significante em praticamente todas as determinações físicoquímicas realizadas, com destaque para o teor de sólidos totais (17,61% e 26,78% para iogurte bovino e bubalino, respectivamente), gordura (2,87% e 4,03% para iogurte bovino e bubalino, respectivamente) e proteína (4,00% e 5,13% para iogurte bovino e bubalino, respectivamente). A acidez do iogurte bubalino (95ºD) está dentro do limite condicionado pela legislação vigente, que estabelece os limites de 0,6 e 0,15 g de ácido láctico/ 100g e valor de proteína superior a 2,9%. Conclui-se, dessa forma, que a produção de iogurte bubalino é viável, tendo em vista os excelentes resultados sensoriais obtidos e índices de aceitação superiores a 70%.Artigo Physicochemical, bioactive and functional evaluation of the exotic fruits Opuntia ficus-indica AND Pilosocereus pachycladus Ritter from the Brazilian caatinga(Springer, 2015-04-07) Souza, Rosane Liége Alves de; Santana, Maristela F. S.; Macedo, Edangelo M. S. de; Brito, Edy Sousa de; Correia, Roberta Targino PintoThe Brazilian caatinga is characterized as one of the most populated and biologically diverse semi-arid regions in the world. Two exotic fruits collected in this unique bioma, the prickly pear (Opuntia ficus-indica) and facheiro (Philosocereus pachycladus Ritter), were investigated in regard to their physicochemical, bioactive and functional characteristics. Four different extracts were prepared and investigated: water (W), ethanol/water 70:100 (E70), ethanol/water 80:100 (E80), and ethanol only (E100). The betalain compounds were investigated using the LC-DAD-ESI-MS technique. The prickly pear fruits are sweeter and less acidic when compared to facheiro fruits, but they also have lower total solids, ash and protein. The total phenolic content (TPC) of water and ethanolic extracts ranged from 8.89 to 12.34 mg GAE/100 g and 82.23 to 107.67 mg GAE/100 g for Opuntia and facheiro fruits, respectively. The identification of betanin and isobetanin derivatives, as well as the TPC, antioxidant and antienzymatic activities of facheiro fruits were reported for the first time. All extracts presented some degree of alpha-amylase and alpha-glucosidase inhibition, with the exception of the facheiro water extracts