http://repositorio.ufc.br/handle/riufc/100 2026-06-11T11:27:37Z http://repositorio.ufc.br/handle/riufc/86508 Título: Uso da lignina de coproduto do pedúnculo do caju como ativo de filmes à base de amido de milho com propriedade de bloqueio da radiação UV Autor(es): Barros, Gleyde Anny Cruz Abstract: Ultraviolet (UV) radiation can accelerate oxidative processes in foods, compromising their sensory and nutritional characteristics. As a strategy to minimize these effects, packaging materials with UV-blocking capacity, as well as active packaging capable of scavenging free radicals, have been increasingly developed. In this context, biodegradable and low-cost biopolymers, such as lignin, have attracted growing attention. This study aimed to develop and characterize corn starch-based biofilms incorporated with lignin extracted from residues of cashew peduncle processing, aiming at their potential application in active food packaging. Films containing 1, 3, and 5% (w/w) lignin were prepared using the casting method and evaluated for rheology, mechanical properties, color, hydrophobicity, UV-blockin/g properties, antioxidant activity, biodegradability, and recyclability. The film-forming solutions exhibited non-Newtonian pseudoplastic rheological behavior (n < 1), with viscosity decreasing as shear rate increased, and the data were adequately described by the Power Law model. The presence of lignin promoted changes in the structural properties of the films, with a reduction in tensile strength (from 13.89 to 6.32 MPa) and an increase in elongation at break (from 29.04 to up to 57%), indicating greater flexibility and deformability of the polymer matrix as lignin concentration increased. Progressive darkening of the films was also observed, with a reduction in lightness (L*) and an increase in reddish and yellowish tones. Furthermore, lignin addition significantly increased the hydrophobicity of the films, reducing water absorption from 86.32% (control) to 68.64% (3% lignin) and increasing the contact angle from 68.62° to 77°. Sorption isotherms showed type III behavior and were satisfactorily fitted by the GAB and Peleg models at 25 and 35 °C. Films containing 3% and 5% lignin completely blocked UV radiation, while antioxidant activity increased proportionally with lignin content. Biodegradation ranged from 33% to 46% after 35 days, and films containing 1% and 3% lignin showed effective recyclability, maintaining their antioxidant and UV-blocking properties after reprocessing. These results demonstrate that lignin derived from cashew peduncle residues is a promising sustainable component for the development of multifunctional active packaging materials, with strong potential to protect foods against photo-oxidative degradation and contribute to extending shelf life. Tipo: Dissertação 2026-01-01T00:00:00Z http://repositorio.ufc.br/handle/riufc/86119 Título: Aplicação de plasma frio por descarga luminosa na inativação de Salmonella enterica e Escherichia coli em agrião (Nasturtium officinale R. Br) Autor(es): Vieira, Raquel Taynan Cunha Abstract: This study evaluated the efficacy of cold plasma generated by glow discharge for the inactivation of Salmonella enterica serovar Typhimurium and Escherichia coli inoculated in watercress (Nasturtium officinale R.Br.), as well as to investigate its effects on cellular viability, microbiological stability during refrigerated storage, and plasma-induced morphological alterations. Plasma treatments were carried out under different operational conditions, varying gas flow rates (10, 20, and 30 mL/min) and exposure times (10, 15, and 20 min). Microbial survival was monitored throughout refrigerated storage by selective plate counts. Residual cellular viability was assessed using the MTT assay, and structural damage was examined by scanning electron microscopy (SEM). The results demonstrated that cold plasma treatment promoted significant pathogen inactivation, with complete elimination of cultivable E. coli and S. Typhimurium in watercress under the most effectve conditions, which were F10T20, F20T20 and F30T20 for E. coli and F10T10, F10T15 and F20T10 for S. Typhimurium. Intermediate treatments also resulted in significant reductions (p < 0.05). When microbial suspensions were treated independently of the food matrix, total inactivation was achieved under all evaluated conditions. The MTT assay confirmed a substantial loss of metabolic activity, with residual viability ranging from 7.68 ± 0.38% to 1.60 ± 0.72% for E. coli and from 17.71 ± 0.94% to 1.46 ± 0.39% for S. Typhimurium, showing a progressive decrease over 72 h of refrigerated storage. SEM images revealed pronounced plasma-induced morphological damage, including cell shrinkage, increased surface roughness, membrane fissures, and structural collapse of bacterial cells. These effects are consistent with oxidative membrane disruption driven by reactive oxygen and nitrogen species generated during plasma discharge. Overall, the findings demonstrate that cold glow discharge plasma is an effective non-thermal intervention for the control of S. Typhimurium and E. coli in leafy vegetables, highlighting its potential application as an alternative decontamination strategy for fresh produce. Tipo: Dissertação 2026-01-01T00:00:00Z http://repositorio.ufc.br/handle/riufc/86100 Título: Obtenção de amido a partir do subproduto do Feijão-caupi verde (Vigna unguiculata (L.) Walp.) e extrato hidroalcoólico da vagem do feijão: caracterização físico-química, análise toxicológica, microbiológica e utilização para produção de microesferas Autor(es): Medeiro, Susan Gabrielly Pereira Abstract: In Brazil, cowpea is a highly important food crop and is cultivated in more than 50 countries worldwide. However, its processing generates residues (pods) and by-products (slightly defective grains), which can be repurposed. Starch, a carbohydrate found in various plants and legumes, has promising industrial potential due to its biodegradability and non-toxicity. Currently, studies have explored the use of starch and plant extracts to produce microspheres, which enhance stability, bioactive compound delivery, and the nutritional value of the matrices used. Thus, the present study aimed to valorize residues and by-products from the processing of green cowpea (Vigna unguiculata (L.) Walp.), focusing on the extraction, characterization, and production of starch–extract microspheres. Four starch extraction methods were evaluated, and the starch obtained by the highest-yield method was selected. The selected starch was characterized for proximate composition, apparent amylose and amylopectin content, FT-IR, NMR, XRD, SEM, GPC, TGA, and DSC, and was subsequently used to produce pod extract microspheres using spray drying technology. The extract was characterized for total phenolic content, antioxidant activity, acute toxicity against Danio rerio, and antimicrobial activity. The microspheres were characterized by color analysis, FT-IR, XRD, SEM, TGA, DSC, antioxidant activity, acute toxicity against Danio rerio, and antimicrobial activity. Ultrasound-assisted extraction showed a yield of 43.70%, with 4.4005 ± 0.42% protein, 8.350 ± 0.095% moisture, 0.188 ± 0.11% ash, pH 6.623 ± 0.136, and amylose and amylopectin contents of 10.99 ± 2.35% and 89.01 ± 2.35%, respectively. The starch exhibited typical physicochemical characteristics of carbohydrates, high purity, preserved morphology, a crystalline pattern typical of conventional starches, and thermal stability suitable for industrial applications. The extract showed low antioxidant activity (0.1344 ± 0.0127 μmol Trolox/g sample) and low total phenolic content (TPC = 48.89 mg GAE/100 g sample), and also reduced zebrafish locomotor activity. However, it demonstrated considerable antimicrobial activity against Staphylococcus aureus, with inhibition halos ranging from 8.357 ± 1.319 to 12.567 ± 0.252 mm. The starch–extract microspheres also exhibited considerable antimicrobial activity against S. aureus, in addition to helping preserve the extract’s properties and the morphological and physicochemical characteristics of the starch. It can be concluded that the residues and by-products generated from green cowpea processing have potential to be converted into higher value-added products, contributing to the development of new products and more sustainable industrial practices. Tipo: Dissertação 2026-01-01T00:00:00Z http://repositorio.ufc.br/handle/riufc/85978 Título: Potencial da farinha de taioba como ingrediente funcional em pães: estudo das propriedades tecnológicas, microestruturais, toxicólogicas e avaliação do perfil glicêmico, lipídico e hepático em modelos in vivo Autor(es): Guimarães, Diana Jéssica Souza Abstract: The food industry always seeks to bring innovations to consumers and meet their needs, especially in terms of nutrition. One way to introduce new technologies to the market is by incorporating more nutritious ingredients into widely accepted products such as bread. In this context, the aim of this study was to develop bread formulations containing Xanthosoma sagittifolium leaf flour at different proportions, to perform their physicochemical characterization, and to evaluate the quality of the developed breads, as well as to assess their microstructures and their influence on the glycemic index (GI) in mice and their evaluation in controlling hyperglycemic conditions in zebrafish. The methodology consisted of evaluating the physicochemical characteristics of the taioba leaf flour and the formulations added with this flour (5%, 7.5%, 10%, 12.5%, and 15%) through analysis of total titratable acidity, pH, moisture, proteins, lipids, fibers, and ashes. The breads were also evaluated for their quality by measuring their specific volume, density, and expansion index. Additionally, the breads were analyzed for their structure using scanning electron microscopy (SEM) and confocal microscopy. The toxicological effect of taioba flour was assessed using Artemia salina. The two formulations that obtained the best technological results were chosen, and their effects on consumption were evaluated using two in vivo models: zebrafish and mice. The fish were subjected to induction of resistant hyperglycemia and tested for the effects of taioba consumption on reducing blood glucose levels. Mice were tested to verify GI and glycemic, lipid, and hepatic profiles. The results showed that the 5% and 7.5% formulations presented the best technological results. The consumption of taioba flour and breads at 5% and 7.5% showed efficient reduction in blood glucose levels in zebrafish. This behavior was also observed in the reduction of blood glucose levels in mice after thirty days of consumption. However, the consumption of these products caused significant changes in hepatic and lipid profiles of the animals, indicating the need for further investigation into the compounds present in taioba leaves and their effects on the metabolism of the animals. Tipo: Dissertação 2023-01-01T00:00:00Z