Rosangela Bergamasco

Estudo do efeito da adição de soro de queijo na qualidade sensorial do doce de leite pastoso

This study aimed to carry out an evaluation of the sensory profile of five samples of creamy dulce de leche made with different concentrations of whey powder or raw whey. The sensory attributes evaluated were appearance, general aspect, color, texture, and intention to purchase. The results were analyzed by ANOVA and Tukey test and showed no significant difference between samples, and thus the use of whey powder or raw whey in the manufacture of creamy dulce de leche is a great alternative to the dairy industry since it enables the achievement of a product with nutritional quality, low cost evidencing the serum use in the food industry and as a nutritional supplement.

Antioxidant and rheological properties of guava jam with added concentrated grape juice

BACKGROUNDnGuava jam enriched by the addition of concentrated grape juice in the proportion of 30% (w/w) (ENR) was studied for its antioxidant potential and rheological behavior. Total phenolics content, 1,1-diphenyl-2-picrylhydrazyl radical (DPPH(•)) scavenging activity and β-carotene-linoleic acid coupled oxidation assays were used to evaluate the antioxidant properties of the samples during storage for 90 days at room temperature (25°C).nnnRESULTSnThe ENR showed a total phenolic content of 11.09 g GAE kg(-1) of jam at production, more than two-fold the phenolic content presented by the standard formulation (STA). For the ENR formulation the antioxidant capacity increased in almost 20% (P ≤ 0.05) with time on the β-carotene assay and decreased with time on the DPPH assay. The enriched guava jam exhibited a non-Newtonian shear-thinning behavior at temperatures ranging from 25 to 55°C, and, moreover, presented higher stability than the standard formulation when exposed to temperature variation.nnnCONCLUSIONnENR constitutes an original food product with a notable antioxidant potential, even greater than the potential presented by the standard guava jam, worldwide appreciated delicacy.

Comparative analysis of the properties of composite mortar with addition of rubber powder from worn tires

This study compares the performance of two plastering mortars. The first one was produced at a 1:6 proportion of quicklime powder and sand (by volume) and ripened. The second had the same proportion but underwent a water withdrawal process in the oven. The mortars were given the same content of cement, making the proportion 1:1.5:9 (by volume), and the addition of rubber powder from worn tires at the proportions of 6%, 8%, 10% and 12% by aggregate volume. Axial compressive strength, flexural strength, deformation energy, void content, water absorption by capillarity, restrained shrinkage, and tensile bond strength were measured. The results showed that the second mortar, with rubber waste, performed better than the ripened mortar. With a reduction in the absorption of water by capillarity in the restrained shrinkage and in the void content, it maintained the tensile bond strength. The energy of deformation rose, although the compressive strength dropped.

APLICAÇÃO DE ÓXIDOS DE FERRO NANOESTRUTURADOS COMO ADSORVENTES E FOTOCATALISADORES NA REMOÇÃO DE POLUENTES DE ÁGUAS RESIDUAIS

New techniques for treating wastewater, particularly the removal or degradation of organic pollutants and heavy metals, among other pollutants, have been extensively studied. The use of nanostructured iron oxides as adsorbent and photocatalyst for the removal of these contaminants has proved a promising approach, not only because of their high treatment efficiency, but also for their cost-effectiveness, having the flexibility for in situ and ex situ applications. In this review, we briefly introduced the most used kinds of iron oxide nanoparticles, some synthesis techniques for iron oxide nanostructure formation, their potential benefits in environmental clean-up, and their recent advances and applications in wastewater treatment. These advances range from the direct applications of synthesized nanoparticles as adsorbents for removing toxic contaminants or as catalysts to oxidize and break down noxious contaminants (including bacteria and viruses) in wastewater, to integrating nanoparticles into conventional treatment technologies, such as composite photocatalytic filters (membranes, sand and ceramic) that combine separation technology with photocatalytic activity. Finally, the impact of nanoparticles on the environment and human health is briefly discussed.

Water Permeability Increase in Ultrafiltration Cellulose Acetate Membrane Containing Silver Nanoparticles

Inorganic nanoparticles incorporation in polymer membranes for filtration processes has attracted the attention of researchers in order to improve in some ways their performance. In this work, AgNPs were synthesized in situ in cellulose acetate (CA) membrane by chemical reduction of a silver salt. The membranes were prepared by the nonsolvent induced phase inversion method. Asymmetric membranes without (CA-M) and with adsorbed AgNPs (CA-Ag-M) were obtained. Ultrafiltration properties were confirmed for both membranes (16 nm of average pore diameter) and average crystallite size of 21 nm for the adsorbed AgNPs was computed. Contact angle measured with Milli-Q water and dry CA-Ag-M is near zero while for the CA-M is around 80o. The CA-M showed water permeability of 214 Lh-1m-2, while the CA-Ag-M permeability was 1651 Lh-1m-2.