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Here, the authors (i) discuss the most prominent co‐catalyst for H2 generation structured in the form of Me‐TiO2/MCM‐41 (Me: Ag, Co, Cu, Ni) based on structural, electronic, textural, morphological and optical characterization techniques, such as XRD, wide and small angle, XPS, Fourier‐transform infrared spectroscopy, scanning electron microscopy, B.E.T., textural analysis, photoacoustic spectroscopy and photoluminescence spectroscopy; and (ii) evaluate the difference in hydrogen production in two distinct geometric reactors based on a theoretical study of light distribution inside the reactors supported by the experimental quantum yield calculation. As a result, copper‐doped photocatalyst generated higher hydrogen amount compared to the others. The high photocatalyst performance was due to the greater lamp spectrum absorption, marked by the low bandgap value, and high photoactivity justified by the low rate of electronic recombination. The hydrogen generation in the quartz reactor was seven times higher than the annular one, and when at maximum light power, it is comparable to the most sophisticated reaction systems found in literature. The larger light exposure area per unit volume of the quartz reactor compared to the annular one is the reason why it obtained better results due to the lower emitted photon blockade, with a 1.81% apparent quantum yield.

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<p>Neste trabalho, buscou-se o enriquecimento nutricional de salgadinhos produzidos a partir da extrusão do gritz de milho, para tanto, duas diferentes formulações foram testadas. A primeira formulação consistiu em utilizar o gritz de milho aplicando-se o processo de nixtamalização; processo este conhecido pelo tratamento do gritz alcalinamente, utilizando o hidróxido de cálcio como agente de tratamento, enquanto que a segunda formulação, foi desenvolvida com gritz sem tratamento. Para a caracterização dos salgadinhos foram realizadas análises da composição centesimal e mineral, cor, textura e índice de expansão. Em relação à composição centesimal e concentração de cálcio, a amostra nixtamalizada apresentou diferença significativa para os parâmetros de cinzas, fibras e cálcio. Os valores obtidos para cinzas, foram de 0,44%±0,02 para os salgadinhos tratados e de 0,24%±0,08 para os não tratados. Para o teor de fibra os valores alcançados foram de 0,83%±0,16 e 0,40%±0,03, para os salgadinhos produzidos com tratamento e sem tratamento, respectivamente. Para o teor de cálcio, constatou-se um aumento superior a 6 vezes entre as formulações, em que 3,02±0,01 (g_Ca/Kg<em>_snack</em>) foram obtidos para o salgadinho nixtamalizado e 0,49±0,003 (g_Ca/Kg<em>_snack</em>) para os salgadinhos produzidos pelo gritz sem aplicação do tratamento. Os teores de umidade, proteínas e lipídeos, não apresentaram diferença significativa entre as formulações. A análise de cor mostrou que o salgadinho não sofreu influência do tratamento alcalino<strong>, </strong>porém a amostra tratada apresentou croma mais intensa. Já para a textura, a nixtamalização exerceu influência significativa para este parâmetro, em que os valores obtidos variaram de 1,95±0,49 N a 0,74±0,16 N para a amostra tratada e para a amostra sem tratamento, respectivamente. O índice de expansão (IE) está diretamente relacionado com a crocância dos salgadinhos, dessa maneira, o (IE) calculado neste trabalho, foi de 4,33 para os salgadinhos tratados e 4,43 para os não tratados alcalinamente, assim, a nixtamalização não interferiu significativamente na determinação deste parâmetro. Este estudo demonstrou que o tratamento alcalino do gritz de milho, seguido do processo de extrusão a alta temperatura, melhorou as características do salgadinho, uma vez que, houve um aumento do teor de cálcio e fibra presente na amostra avaliada.</p><p align="center"><strong><em>Development and characterization of snacks made from nixtamalized corn grits</em></strong></p><p><strong>Abstract</strong><strong>: </strong>In this work, we sought to nutritional enrichment of chips produced from extruded corn grits, therefore, two different formulations were tested. The first formulation consisted of using corn grits applying the nixtamalization process; this known process by treating the alkali-grits using calcium hydroxide as the treatment agent, while the second formulation was developed with untreated grits. To characterize the <em>snacks</em> were performed analyzes of proximate and mineral composition, color, texture and expansion ratio. Regarding the chemical composition and concentration of calcium, nixtamalizada sample showed significant differences for the parameters of ash, fiber and calcium. The values obtained for ashes were 0.44 ± 0.02% for the treated chips and 0.24 ± 0.08% for the untreated. For the fiber obtained values were 0.83 ± 0.16% and 0.40 ± 0.03% for the snack foods produced with treatment and without treatment, respectively. To the calcium content, there was an increase of 6 times in the formulations, wherein 3.02 ± 0.01 (g_Ca/Kg<em>_snack</em>) were obtained for nixtamalizado snack and 0.49 ± 0.003 (g_Ca/Kg<em>_snack</em>) to the chips produced by the grits without the application of treatment. The moisture, protein and lipids, no significant differences between formulations. The color analysis showed that the snack not influenced by alkali treatment, but the treated sample had stronger chroma. As for the texture, nixtamalization in significant difference for this parameter, wherein the values obtained ranged from 1.95 ± 0.49 N 0.74 ± 0.16 N for the treated sample and the untreated sample, respectively. The expansion index (EI) is directly related to the crispness of <em>snacks</em>, this way, the (IE) calculated in this study, was 4.33 to 4.43 for <em>snacks </em>treated and untreated alkali-thus the nixtamalization did not interfere significantly in the determination of this parameter. This study demonstrated that the alkaline treatment of corn grits, followed by the process of high temperature extrusion, snack improved characteristics, since there was a increase in the calcium content and fiber present in the sample evaluated.<strong></strong></p>