DSpace Coleção: PPGCTA

Fermentação probiótica : uma estratégia para valorização de frutas nativas subexploradas

Thu, 15 May 2025 00:00:00 GMT

Título: Fermentação probiótica : uma estratégia para valorização de frutas nativas subexploradas Autor(es): Assis, Bianca Beatriz Torres de Orientador: Magnani, Marciane Abstract: Brazil has a wide diversity of native fruits that are rich sources of bioactive compounds, yet they remain underexplored, particularly in the North and Northeast regions of the country. Mangaba (Hancornia speciosa Gomes) and bacaba (Oenocarpus bacaba Mart.) are Brazilian fruits abundant in the Northeast and North regions, respectively, and stand out for their nutritional value. They contain bioactive compounds with potential health-promoting properties. Due to their seasonality and high perishability, these fruits are mainly consumed locally in the form of fruit pulps and remain undervalued. In this context, this thesis was divided into five stages, including two experimental phases. These phases evaluated the technological parameters (pH, total soluble solids, and titratable acidity) and functional aspects (probiotic viability and bioaccessibility) during 48 hours of fermentation and refrigerated storage of mangaba and bacaba pulps inoculated with Lacticaseibacillus casei (LC1) and Lactobacillus acidophilus (LA-05). Additionally, the contents of sugars, organic acids, phenolic compounds, and volatile composition were analyzed in the mangaba pulp over 48 hours of fermentation and storage, and the contents of sugars, organic acids, and phenolic compounds in the bacaba pulp were analyzed during 48 hours of fermentation. Next, the sensory profile of the fermented mangaba pulp was determined using the Preferred Attribute Elicitation (PAE) methodology. Finally, the prebiotic potential of the fermented mangaba and bacaba pulps was evaluated using in vitro colonic fermentation systems inoculated with the gut microbiota of vegan and healthy adults, respectively, through 16S rRNA gene sequencing. The results demonstrated that mangaba and bacaba pulps are suitable substrates to maintain probiotic viability at counts ≥7 log CFU/g and to protect probiotics during exposure to simulated gastrointestinal conditions, ensuring their viability in the intestinal fraction. The probiotic fermented pulps of mangaba and bacaba showed higher concentrations of organic acids, including lactic and propionic acids, and phenolic compounds such as trans-resveratrol, procyanidin B1 and B2, epicatechin, and others. Probiotic fermentation enhanced the bioaccessibility of epicatechin, procyanidin B1, kaempferol 3-glucoside, and caffeic acid in mangaba pulp, and of procyanidin B1 and B2, trans-resveratrol, cis-resveratrol, catechin, epicatechin, and myricetin in bacaba pulp, when compared to the non-fermented pulps. Fermented mangaba pulp increased the relative abundance of Dorea, Romboutsia, and Faecalibacterium, while fermented bacaba pulp increased the abundance of Acidaminococcales, Enterobacterales, and Lactobacillales—microbial groups associated with the production of health-promoting metabolites such as butyrate, acetate, and propionate. Fermented fruit pulps also positively influenced microbial diversity indices, resulting in a balanced and functional gut microbiota. Sensory evaluation of fermented mangaba pulp revealed probiotic viability over 28 days, stability of bioaccessible phenolic compounds, antioxidant activity, and maintenance of quality parameters. The fermented mangaba pulp received higher scores than the non-fermented version for sensory attributes such as color, brightness, freshness, and aroma throughout the storage period, supporting the development of a new functional product. Editor: Universidade Federal da Paraíba Tipo: Tese

Aplicação de tecnologias não térmicas no processamento do açaí (Euterpe oleracea Mart.)

Thu, 17 Mar 2022 00:00:00 GMT

Título: Aplicação de tecnologias não térmicas no processamento do açaí (Euterpe oleracea Mart.) Autor(es): Dantas, Aline Macedo Orientador: Borges, Graciele da Silva Campelo Abstract: The main process to which açaí is submitted is to obtain its frozen edible part, known as "açaí pulp" or just "açaí". The Brazilian legislation recommends that the pulp be pasteurized in order to reduce the enzymatic activity and the microbial load. However, pasteurization causes a reduction of some nutrients, bioactive compounds, and changes in sensory characteristics. Thus, studies with the application of non-thermal technologies have been proposed to reduce these losses. Thus, the objective of this work was to evaluate the effects of the application of atmospheric cold plasma (ACP) and continuous ultrasound (US) on the enzymatic activity, color, antioxidant activity, anthocyanin content, phenolic compounds and their bioaccessibility in açaí pulp. In the treatment with ACP the variables excitation frequency (50, 500 and 750 Hz) and time (5, 10 and 15 min) were studied, and in the treatment with continuous US the variables power (100, 120 and 150 W) and passage cycles (1, 2, 3 and 5 cycles) were studied, in both technologies studied the variables responses were enzymatic activity, color, antioxidant activity, and total content of phenolics and total monomeric anthocyanins. The processing at 50 Hz/15 min showed greater reduction in polyphenoloxidase (82.4%) and peroxidase (42.3%) activity (p < 0.05), while in the 50 Hz/10 min condition there was an increase in the bioaccessibility of catechin (194.70%), epicatechin (383, 44%), epigallocatechin gallate (68.84%), procyanidin B1 (130.71%), rutin (16.84%), caffeic acid (341.48%) and chlorogenic acid (57.63%), contributing to the increase in antioxidant activity of the bioaccessible fraction evaluated by DPPH and ORAC assays. The continuous US technology increased the intensity of the purple color and the phenolic content and reduced the activity of polyphenoloxidase by 62.24% (100 W/2 cycles) and peroxidase by 41.91% (150 W/1 cycles). Furthermore, the treatments 100 W/2 cycles and 150 W/1 cycle increased the bioaccessibility of catechin (131.05% and 107.12%), epicatechin (183.57% and 356.19), epigallocatechin gallate (77.54% and 303.54%), procyanidin B1 (115.49% and 99.72%) and procyanidin A2 (124.40% and 128.18%) with consequent elevation of antioxidant activity. The results indicate that PFA and continuous US contribute to reduction of polyphenoloxidase and peroxidase activity, as well as to quality and bioaccessibility of phenolic compounds in açaí pulp. However, optimization protocols should be studied to achieve the best product quality. Editor: Universidade Federal da Paraíba Tipo: Tese

Obtenção e avaliação das frações lipossolúvel e hidrossolúvel de sementes de urucum (Bixa orellana L.) por tecnologia verde

Thu, 26 Aug 2021 00:00:00 GMT

Título: Obtenção e avaliação das frações lipossolúvel e hidrossolúvel de sementes de urucum (Bixa orellana L.) por tecnologia verde Autor(es): Franca, Simone Alves Monteiro da Orientador: Madruga, Marta Suely Abstract: The search for the offer of new food products and the concept of clean labeling has further boosted the global market in the demand for natural ingredients and additives to replace synthetic ones. Among the ingredients, the colorants obtained from the seeds of the annatto (Bixa orellana L.) are industrially extracted by methods that have disadvantages, such as the degradation of thermosensitive bioactive compounds and the generation of harmful residues to the environment. In this context, the present study aimed to evaluate the efficiency of the process of obtaining simultaneous fat-soluble (FL) and water-soluble (FH) fractions of annatto seeds, by green technology, in terms of overall yield (mass), yield of pigments (bixin and norbixin) and bioactive compounds (total phenolics and flavonoids), antioxidant and antimicrobial activities and economic viability of the process. Three batches of annatto seeds were submitted to the refrigerated solid-liquid extraction process, in four stages: pre- extraction, aqueous extraction, separation by decantation and filtration. The process was efficient, in terms of overall average yield, FL = 8.68% and FH = 2.76%, and in terms of quality, mean lipid yields FL = 11.83%, bixin FL = 82.34% and norbixin FH = 29.59%, total phenolics (GAE) FL = 13.18% and FH = 23.48%, total flavonoids (RU) FL = 34.78% and FH = 5.70% and total flavonoids (CA) FL = 73.69% and FH = 18.48%. The composition of the fractions influenced the colorimetric attributes of FL, which showed greater intensity of red (a* ), associated with the content of lipids (r = 0.82) and bixin (r = 0.57), and of FH, which presented greater intensity of yellow (b* ), associated with the content of norbixin (r = 0.63) and total phenolics (r = 0.53). The higher concentration of norbixin and total phenolic, in the FH fraction, and bixin and flavonoids in the FL fraction, promoted an increase in the inhibition of free radicals (DPPH* and ABTS*+) and of the ferric reducing power (FRAP), while the inhibition of thiobarbituric acid reactive substances (TBARS) was reduced to FL, which may be associated with the yield of lipids in this fraction. As for the antimicrobial activity, the FL extract presented a minimum inhibitory concentration (MIC) of 0.06 mg mL-1 for Staphylococcus aureus and 0.13 mg mL-1 for Salmonella Typhimurium and Salmonella Enteritidis, while the FH fraction did not inhibit the growth of the strains tested. The lowest costs were obtained for the FL fraction due to its higher extraction yield compared to the FH fraction. The extract production rate also increased with increasing scale and therefore the COM of the extract decreased. Plants in industrial scale of 1 and 10 L were considered economically unviable; however, 100 and 1000 L plant units achieved payback times of about 5 and 2 years, respectively. The fractions can be applied in the food industry as natural additives with coloring, antioxidant and antimicrobial functions, as a source of bioactive compounds in the preparation of nutraceutical and/or pharmaceutical products, and in the development of other innovative processes. Editor: Universidade Federal da Paraíba Tipo: Dissertação

Filme inteligente à base de colágeno incorporado com antocianinas da flor de catharanthus roseus e sua aplicabilidade no monitoramento do frescor de oreochromis niloticus por meio de inteligência artificial

Tue, 24 Feb 2026 00:00:00 GMT

Título: Filme inteligente à base de colágeno incorporado com antocianinas da flor de catharanthus roseus e sua aplicabilidade no monitoramento do frescor de oreochromis niloticus por meio de inteligência artificial Autor(es): Florentino, Gabrielle Ingred Bizerra Orientador: Silva, Fábio Anderson Pereira da Abstract: This study aimed to evaluate the impact of different concentrations of anthocyanin extract (CAE), extracted from Catharanthus roseus flowers, on the development of smart films applied to monitoring the freshness of tilapia fillets (Oreochromis niloticus), using artificial intelligence for real-time detection of changes in fish quality. Hydroalcoholic extraction of anthocyanins was performed from the flowers, while collagen was obtained from tilapia skin by hot water extraction; both were characterized in terms of their physicochemical properties. For the elaboration of the films, collagen and pectin were used as polymeric matrices, incorporating different concentrations of anthocyanin extract in the FC (control), F10, F20, and F30 formulations. The physical, mechanical, thermal, functional, and morphological properties were evaluated, including the response to pH variations. The film with the best performance was selected for application to tilapia fillets stored under refrigeration for eight days. The film's color changes, associated with total volatile basic nitrogen (TVB-N) and pH values, were used to create a database for training artificial intelligence models. Complementary analyses were performed to validate the correlation between the colorimetric response and the degree of fish deterioration, including TBARS, microorganism count, texture, volatile compounds, and sensory evaluation. The results indicated a collagen extraction yield of 6.31%, with a hydroxyproline content of 4.83 g/100 g, and preservation of the triple helix structure confirmed by FTIR. The anthocyanin extract showed a concentration of 4.78 mg CGE/g and high antioxidant activity, with a phenolic profile composed of phenolic acids, flavonoids, and anthocyanins, in addition to color variation as a function of pH, highlighting its potential as a freshness indicator. The films exhibited alterations in physical and morphological properties, such as reduced thickness, transparency, luminosity, and elasticity, due to interactions with the polymeric matrix. The incorporation of the extract did not compromise non-toxicity, water vapor permeability, or mechanical integrity, maintaining adequate solubility and thermal stability. The F30 formulation stood out for its higher antioxidant activity and sensitivity to ammonia. During storage, an increase in pH and TVB-N, a reduction in hardness and chewiness, and the formation of deterioration compounds were observed, accompanied by a loss of sensory acceptability. The colorimetric response of the film correlated with these parameters and was applied in a machine learning system integrated into the SmartFish application, which classified the freshness of tilapia into three levels with 93% accuracy. Thus, the system demonstrated high efficiency and potential for practical application in monitoring fish freshness. Smart films with anthocyanins from Catharanthus roseus have proven effective, especially the F30 formulation, and integration with artificial intelligence has shown a promising approach to increase food safety and reduce waste. Editor: Universidade Federal da Paraíba Tipo: Tese