Mesoporous titanium dioxide nanocatalyst: a recyclable approach for one‐pot synthesis of 5‐hydroxymethylfurfural

The present study deals with the production of 5‐hydroxymethyl furfural (HMF) from fructose by chemo‐conversion method using chemical catalyst, conventionally achieved by microwave‐assisted dehydration process. Five different chemical catalysts, namely oxalic acid, phosphotungstic acid and mesoporous titanium dioxide nanoparticles (TNPs) were compared at constant conditions of which TNPs yielded a maxima of 33.95%. The optimum temperature and catalyst loading were found to be 200°C and 20%, respectively, at a 5% optimum substrate concentration during 15 min optimum reaction time to yield 61.53% HMF. The efficiency of synthesised TNPs was investigated further through reusability studies. TNPs were properly recycled and the catalytic activity recovery was good even after a 14 batch reactions. The specific surface area of the TNP obtained is about 105.46 m² /g and its pore‐volume is about 0.42 cm³ /g according to single point adsorption. A large accessible surface area combined with a minimal pore size (15.92 nm) obtained with mesoporous TNPs is desirable for better catalyst loading, high‐yield HMF, retention and reduced diffusion constraints.Inspec keywords: mesoporous materials, recycling, production management, dissociation, nanoparticles, nanotechnologyOther keywords: mesoporous titanium dioxide nanocatalyst, recyclable approach, one‐pot synthesis, 5‐hydroxymethyl furfural production, HMF, chemo‐conversion method, chemical catalyst, microwave‐assisted dehydration process, oxalic acid, phosphotungstic acid, mesoporous titanium dioxide nanoparticles, TNP     

Vacuum-based preservation of surgical specimens: An environmentally-safe step towards a formalin-free hospital

Formalin as a fixative has no practical substitutes, but is toxic and potentially carcinogenic, so caution of its use in hospitals and elsewhere is mandatory. In our hospital, preservation of surgical specimens into formalin to be transferred to pathology labs was replaced by under-vacuum sealing (UVS) tissues into plastic bags and preservation at 4 °C until transfer. Data analysis showed UVS processing to be superior in terms of staff satisfaction and of gross anatomic preservation; no problems in terms of technical feasibility or histopathologic preservation were encountered. Formalin was confined to pathology labs while its use on hospital premises was vastly reduced.     

Germinated or fermented legumes: food or ingredients of functional food

Epidemiological research has shown a positive association between certain diseases and dietary intake of food components found in fruits, grains, legumes, fish oil among others. Food that may provide a health benefit beyond the traditional nutrients that it contains, are named functional food. In addition to the varied nutrients, legumes contain compounds such as polyphenols, soluble fiber, alpha-galactosides and isoflavones which confer propierties of functional foods. Do to the cuse of flatus production in some people, long cooking periods, or anti-nutritional factors, legume consumption levels are limited. In this review, germination and fermentation processes will be presented as alternatives that are able to reduce or inactivate anti-nutritional factors, preserve and even improve the content of the isoflavones, or better the potencial of the legumes as functional food or as ingredients for the formulation of functional foods.     

Baked product development based fermented legumes and cereals for schoolchildren snack

The objective of this work was to develop three foodstuffs based on mixes of wheat and fermented and non-fermented legumes, for the purpose of contributing with a healthy alternative for school snacks. To this aim, refined wheat flour was partially substituted with whole legume flours for the preparation of cakes, brownies and cookies, foodstuffs traditionally consumed by school age children. Cakes were formulated substituting 20% of wheat flour with Phaseolus vulgaris flour, brownies with 30% of Cajanus cajan flour and cookies with 30% of Vigna sinensis flour, using fermented and non-fermented legumes in the three products. When these products were subjected to sensorial evaluation through a test of degree of acceptability and using a hedonic scale of 7 points, values higher than 5 in the attributes taste, color and overall appraisal were found for all the products. In addition, the preference was measured with a group of 90 school children, corroborating the results obtained at laboratory level. Chemical characterization showed protein contents between 12 and 13% for the cake, 10 and 11% for the brownies and 10% for the cookies and protein digestibilities in vitro of 91%, 87% and 93%, respectively. The calorie supply, calculated per portion was of 199 kcal, 246 kcal and 237 kcal, for cakes, brownies and cookies, respectively. It was concluded that it is technically possible to incorporate fermented and non-fermented Phaseolus vulgaris, Vigna sinensis and Cajanus cajan, to highly consumed products such as cakes, brownies and cookies with a higher nutritional content and well-accepted by school-age children.     

Effect of natural and controlled fermentation on flatus‐producing compounds of beans (Phaseolus vulgaris)

Fermentation of grain legumes is an efficient method to reduce the concentration of α‐galactosidic compounds that are known to be flatulence producers. Soluble dietary fibre has also been implicated in flatulence production; however, little information exists about the effectiveness of fermentation in diminishing the effects of these compounds. The objective of this work was to study the effect of natural fermentation (NF) and controlled fermentation (CF) on the content of α‐galactosides and dietary fibre in dry beans (Phaseolus vulgaris) for 24, 48, 72 and 96 h. After 48 h, the pH during NF dropped from 6.15 to 4.00 and the nominal acidity increased six times; for CF, however, although the decrease in pH was similar to that for NF, the nominal acidity increased only three times after 48 h. Insoluble fibre content did not change the pH significantly after 96 h for NF and CF. Soluble fibre suffered an apparent removal after 48 h of NF and underwent a sharp reduction of 66% after 96 h of CF. The concentration of stachyose (the main α‐galactoside in raw beans) diminished notably after 48 h and 96 h NF (72% and 95% respectively), whereas with CF only 11% was removed after 96 h. NF of P vulgaris seems to be more effective than CF in reducing the flatulence‐producer factors (α‐galactosides and soluble dietary fibre). Copyright © 2003 Society of Chemical Industry     

在环境友好的电解液中电沉积铅粉末的形态和晶体学特征

采用扫描电镜（SEM）研究在碱性电解液中通过恒电位沉积得到的铅粉。结果表明：铅晶体的形状主要取决于电沉积的过电位。通过欧姆控制步骤可以得到规则晶体。通过扩散控制得到的枝晶形状和电沉积的过电位有关系。不断增加的过电位导致枝晶的分枝从原始类型变成发达的三级分枝。基于该电解液属于络合铅电解液,解释具有强烈的（111）择优取向的枝晶分枝的形成原因。     

An attempt to predict pork drip loss from pH and colour measurements or near infrared spectra using artificial neural networks

The ability to predict meat drip loss by using either near infrared spectra (SPECTRA) or different meat quality (MQ) measurements, such as pH₂₄, Minolta L^∗, a^∗, b^∗, along with different chemometric approach, was investigated. Back propagation (BP) and counter propagation (CP) artificial neural networks (ANN) were used and compared to PLS (partial least squares) regression. Prediction models were created either by using MQ measurements or by using NIR spectral data as independent predictive variables. The analysis consisted of 312 samples of longissimus dorsi muscle. Data were split into training and test set using 2D Kohonen map. The error of drip loss prediction was similar for ANN (2.2–2.6%) and PLS models (2.2–2.5%) and it was higher for SPECTRA (2.5–2.6%) than for MQ (2.2–2.3%) based models. Nevertheless, the SPECTRA based models gave reasonable prediction errors and due to their simplicity of data acquisition represent an acceptable alternative to classical meat quality based models.     

Porous activated carbon monolith with nanosheet/nanofiber structure derived from the green stem of cassava for supercapacitor application

Carbonization and activation have been exploited as an economic and efficient approach toward the production of porous activated carbon monolith derived from green stem of cassava (GSC). In addition, ZnCl₂ was used as a chemical activator agent at various concentrations, therefore serving as a key factor in the development of porous carbon. The carbonization process (N₂) was integrated with physical activation (CO₂), and then N₂ sorption, scanning electron microscopy, X-ray diffraction, energy dispersive X-ray were examined to evaluate the specific surface area, pore structure characteristic, morphology structure, crystallinity, and the surface element, respectively. Furthermore, cyclic voltammetry was used to measure the electrochemical performance, through a two-electrode system in 1M H₂SO₄. Therefore, the synthesized porous activated carbon exhibits a micropores-mesopores combination, and the optimized sample demonstrated nanosheet and nanofiber structures. The results show a high electrochemical behavior in 1M H₂SO₄ electrolytes, by the electrodes, with specific capacitance, energy, and power densities of 164.58 F g⁻¹, 22.86 Wh kg⁻¹, and 82.38 W kg⁻¹, respectively. This route confirms the opportunity of using novel GSC in the production of porous carbon monolith with nanosheet/nanofiber structure for supercapacitor applications.     

Lactic acid fermentation of black beans (Phaseolus vulgaris): microbiological and chemical characterization

Legumes, and particularly Phaseolus vulgaris, are an important source of nutrients, especially in developing countries. In spite of being part of the staple diets of these populations, their consumption is limited by the flatulence they produce. Natural lactic acid fermentation has proved to be an effective method to decrease flatulence‐producing compounds. However, in order to use this method as a process on a large scale, it is fundamental to identify the microbial flora involved. When fermented seeds of Phaseolus vulgaris (black bean) were analysed microbiologically, it was found that the microorganisms present were Lactobacillus casei and Lactobacillus plantarum. On performing back‐slopping or induced fermentation with different inocula, a 63.35% decrease was found for the soluble fibre and 88.6% for raffinose, one of the main flatulence‐producing compounds. When cooking under atmospheric pressure was applied to the fermented samples, a significant diminution of the trypsin inhibitors and tannins was found as well as an increase in the in vitro and in vivo digestibility of the beans. All these results demonstrate that the lactic acid bacteria used for the induced fermentation can lead to a functional food with improved nutritional quality. Copyright © 2006 Society of Chemical Industry