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Embalagem inteligente adicionada de betalaínas extraídas de beterraba (Beta vulgaris L.) como indicador de frescor em peixe

2026-05-22T06:09:44Z

Título: Embalagem inteligente adicionada de betalaínas extraídas de beterraba (Beta vulgaris L.) como indicador de frescor em peixe Autor(es): Araújo, Patrícia Lima Orientador: Meireles, Bruno Raniere Lins de Albuquerque Abstract: Fish is an important food in the human diet, due to its profile in essential polyunsaturated fatty acids. However, this characteristic makes it very susceptible to undesirable sensory and physicochemical changes caused by lipid oxidation. These limiting factors, combined with the high level of demand from the consumer market, require the development of mechanisms to ensure greater stability and quality monitoring for this raw material, such as intelligent packaging. Thus, the objective was to develop a smart packaging added with beet extract (Beta vulgaris L.) by headspace in the tilapia fillet, and evaluate the colorimetric changes of the film and quality parameters of the tilapia. In addition, the extract was characterized and the thermal, mechanical, morphological and colorimetric characteristics of the packaging were evaluated. Three treatments were evaluated: C (control), T2.5% (addition of 2.5% extract) and T5.0% (addition of 5.0% extract). Beetroot extract showed significant content of betalains (644.85 mg/L), total phenolic compounds (540.60 mg EAG/100g), antioxidant activity by DPPH (0.95 μmol ETrolox/mL), FRAP (3.62 μmol ETrolox/mL) and ABTS (2.92 μmol ETrolox/mL), in addition to desirable color parameters that are perceptible to the human eye. The physicochemical characteristics, pH, volatile bases (NBVT) and lipid oxidation (TBA) of tilapia were in accordance with the standards required by current Brazilian legislation for fish and fish. The scanning electron microscopy images of the C and T2.5% treatments mostly showed a homogeneous surface and cross-section, without the presence of grooves or any other empty space. The films were applied by headspace to the tilapia fillet and analyzed over the course of four days at room temperature, showing color changes in the packaging, with a decrease in red color values (a*) and a consequent increase in yellow color (b*). The pH, total bacterial count and NBVT values were high on the last day of monitoring, however, the TBA values had no significant changes with a maximum value of 0.4 mg MDA/Kg. Therefore, the application of intelligent headspace packaging added with beet extract (Beta vulgaris L.) to tilapia fillet was efficient in indicating the quality of the fish through colorimetric modifications of the films, as well as increasing stability against NBVT and total bacteria count. Editor: Universidade Federal da Paraíba Tipo: Dissertação

Aplicação de novas cepas de Lactobacillus spp. como cultura iniciadora na produção de fermento natural fresco e liofilizado e seus impactos na produção e qualidade de pães de longa fermentação

2026-05-21T06:07:34Z

Título: Aplicação de novas cepas de Lactobacillus spp. como cultura iniciadora na produção de fermento natural fresco e liofilizado e seus impactos na produção e qualidade de pães de longa fermentação Autor(es): Santos, Joanderson Gama Orientador: Gonçalves, Ingrid Conceição Dantas Abstract: Mature sourdough composes a rich and diverse microbiota, mainly of lactic acid bacteria (LAB) and yeast. Its secondary metabolites are responsible for conferring technological properties on sourdough and long-fermentation breads. The biochemical transformations that occur at all stages, from its preparation, passing through propagation, and, finally, through its use in the production of long-fermentation breads, have an impact on the production of breads with sensory and quality characteristics that differentiate it from traditional bread. Dehydrated sourdough aims to minimize production, storage and logistics costs on a large scale, actions that are difficult when sourdough is used in its fresh form and enable the production of long-fermentation breads. Therefore, the study was divided into two stages. In the first stage, five strains of Lactobacillus spp. as starter cultures in the production and propagation of sourdough, using wheat flour and water as substrates. For the production of sourdough, three strains were selected that showed the best results according to the applied protocols (Limosilactobacillus fermentum 56, Lactiplantibacillus pentosus 129 and Limosilactobacillus fermentum 139). The sourdoughs showed stable microbiota and characteristic pH after 10 days of propagation. Immediately after maturation, the breads were prepared with their respective fresh sourdoughs and presented satisfactory technological and quality characteristics during storage, mainly in the breads produced from the inoculation of strains of L. pentosus 129 and L. fermentum 139 as starter cultures of sourdough. The freeze-dried of sourdoughs were part of the second stage of this study and aimed to produce sourdough with L. pentosus 129 and L. fermentum 139 strains in a single culture or co-culture, evaluate their stability during 60-day storage and produce long-fermentation breads as the final product obtained (dehydrated sourdough). During storage, the freeze-dried sourdoughs showed excellent stability (microbiological and physical-chemical) and high viable cell counts (between 6 – 8 log CFU/g) which was confirmed by flow cytometry (> 70%). Among the samples of freeze-dried sourdough and their respective breads, the bread produced with freeze-dried sourdough with the strain L. fermentum 139 showed the best results in the evaluated parameters (texture, specific volume, and protein digestibility in vitro). An intellectual property request was made for the freeze-dried sourdough inoculated with the L. fermentum 139 strain. Finally, based on the results obtained it was possible to produce freeze-dried sourdoughs from Lactiplantibacillus pentosus 129 and Limosilactobacillus fermentum 139 strains with technological characteristics similar to fresh sourdough and with leavening activity that eliminates the use of baker's yeast that act in the rapid fermentation and production of gases necessary for the increase in bread volume. Editor: Universidade Federal da Paraíba Tipo: Dissertação

Potencial dos pós de beterraba (Beta vulgaris L.) e rúcula (Eruca sativa L.) como substitutos ao nitrito de sódio na cura do salame tipo italiano

2026-05-21T06:07:32Z

Título: Potencial dos pós de beterraba (Beta vulgaris L.) e rúcula (Eruca sativa L.) como substitutos ao nitrito de sódio na cura do salame tipo italiano Autor(es): Santos, Maria de Fátima Clementino dos Orientador: Silva, Fábio Anderson Pereira da Abstract: Sodium nitrite (NaNO2) is one of the main curing agents used in the meat industry, being responsible for the development of unique sensory attributes, microbiological safety and maintenance of the quality of cured products. However, the use of NaNO2 in curing meat has been associated with the formation of N-nitroso compounds, which can trigger abnormalities and cellular stress, causing harm to health. Beets and arugula have high concentrations of nitrate that can be converted to nitrite in the presence of nitrate-reducing microorganisms. In this sense, the objective was to evaluate the effect of using beetroot powder and/or arugula as an alternative source of nitrate and nitrite in Italian salami, evaluating the effects of this substitution during the product processing period (beginning, after fermentation and after maturation). The experiment was conducted in two phases: in the first stage, beet powders (B100%), arugula (R100%) and their mixture (RB50%) were obtained and characterized. In the second stage, 4 salami treatments were prepared: CT (control added with NaNO2 e NaNO3), BT (added with B100%), RT (added with R100%) and RB (added with RB50%). At each processing stage, chemical and physical parameters, lipid oxidation and curing properties were evaluated. Additionally, an SDSPAGE electrophoresis analysis was performed to evaluate the proteolysis of salami at the beginning and end of processing. Nitrate concentrations were highest in B100%, followed by RB50% and R100%. For salami, samples CT, BT, RT and RB achieved 35% weight loss at 45, 36, 36 and 30 days, respectively, causing water activity to reach values less than or equal to 0.90 at the end. Of maturation. As expected, there was a decrease in pH for all treatments and the samples added with arugula powder tended towards a greener color. The lowest levels of residual nitrite were observed in CT and RB salami (< 0,9 mg/kg). The curing efficiency (EC) of all samples was higher at the end of fermentation (≥ 30%). All treatments presented final TBARS values below 0.6 MDA/kg (P<0.01). In the electrophoresis analysis, protein bands with weights between 15 and 220 KDa were observed, with a decrease in intensity and the appearance of new bands between the beginning and end of processing, indicative of proteolysis. The analysis of main components allowed a better visualization of the correlation of the analyzed attributes with the treatments, observing a clear separation of the samples depending on the processing stage and type of powder. At the end of processing, it was possible to notice that all samples prepared presented a chemical composition in accordance with the requirements of Brazilian legislation for Italian-style salami. Based on the results, the use of beetroot powder, alone or combined with arugula, shows promising results as a substitute for NaNO₂ and NaNO₃ in Italian-style salami. The RB treatment stood out, resulting in the highest quality product. Editor: Universidade Federal da Paraíba Tipo: Dissertação

Identificação e seleção de cepas de fermentos naturais de diferentes regiões da Paraíba e estudo do potencial tecnológico e bioativo para panificação

2026-05-21T06:07:28Z

Título: Identificação e seleção de cepas de fermentos naturais de diferentes regiões da Paraíba e estudo do potencial tecnológico e bioativo para panificação Autor(es): Medeiros, Ana Regina Simplício de Orientador: Cordeiro, Angela Maria Tribuzy De Magalhães Abstract: This study aimed to develop a dominant sourdough starter with controlled characteristics, derived from strains of Lactic Acid Bacteria (LAB) isolated from different climatic regions of Paraíba, with technological and bioactive potential. Initially, four sourdough starters were collected from municipalities within the humid, subhumid, and semi-arid regions. The microbiota of these starters was isolated and preliminarily identified. Out of 129 isolates obtained, 24 exhibited typical LAB characteristics and were identified by mass spectrometry (MALDI-TOF) as Lactiplantibacillus plantarum, Companilactobacillus paralimentarius, and Levilactobacillus brevis. C. paralimentarius predominated in the humid region, while L. plantarum dominated in the other regions. Through principal component analysis (PCA), 17 strains were selected for their superior technological potential. These strains were tested for stress tolerance to acid, salt, sucrose, and ethanol at various concentrations. L. plantarum 47 (Lp47) and L. brevis 83 (Lb83) were selected by PCA due to their superior performance for use as starter cultures. Lp47 was the most tolerant under acidic and saline conditions, while Lb83 stood out for its higher survival at high ethanol concentrations. These strains were selected for the development of the sourdough starter and demonstrated good physicochemical, bioactive, and technological performance. The rapid growth and acidification of Lp47 and Lb83 are directly associated with their autochthonous origin and adaptation to the stressful conditions of the sourdough. However, Lp47 acidified the medium more quickly, stabilizing its viable cell count after 4 hours of fermentation, while Lb83 stabilized its count after 6 hours. Both starters exhibited antioxidant activity and an increase in phenolic compounds during fermentation, with no significant difference between them (p>0.05). In terms of rheology, the rigidity of the samples after 8 hours of fermentation was approximately 10 times greater than that of the samples fermented for 24 hours. The results demonstrated the feasibility of using Lp47 or Lb83 as starter cultures for sourdough, highlighting that autochthonous strains excel in technological development in baking processes and are recommended for initiating this process in a rapid, controlled, and safe manner. Editor: Universidade Federal da Paraíba Tipo: Dissertação