Programa de Pós-Graduação em Ciência e Tecnologia de Alimentos - PPGCTA/ITEC

URI Permanente desta comunidadehttps://repositorio.ufpa.br/handle/2011/8900

O Programa de Pós-Graduação em Ciência e Tecnologia de Alimentos (PPGCTA) integra o Instituto de Tecnologia (ITEC) da Universidade Federal do Pará (UFPA) e iniciou suas atividades em 2004 com o curso de Mestrado Acadêmico em Ciência e Tecnologia de Alimentos. Em 2010, a CAPES aprovou o Doutorado, que teve início em 2011.

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Agora exibindo 1 - 14 de 14

Acesso aberto (Open Access)
Arrabidaea chica(Humb. & Bonpl.) Verlot: Identificação de compostos bioativos e avaliação do potencial antioxidante por métodois químicos (in vitro)
(Universidade Federal do Pará, 2022-04-28) SIQUEIRA, Francília Campos de; CHISTÉ, Renan Campos; http://lattes.cnpq.br/0583058299891937; LOPES, Alessandra Santos; http://lattes.cnpq.br/8156697119235191
Arrabidaea chica is a medicinal plant from the Bignoniaceae family, which occurs in tropicalAmerica and it is widely distributed in the Brazilian Amazonia. This plant can be seen as apromising source of bioactive compounds, such as phenolic compounds and carotenoids,which are secondary plant metabolites that can be used to delay oxidative damage in bothfood and biological systems. In this study, the composition of carotenoids and phenoliccompounds of A. chica leaves were identified and quantified by HPLC-DAD-MS/MS, inaddition to the ascorbic acid content. The main phenolic compounds identified werescutellarin and scutellarein (aglycone); while lutein, β-carotene and α-carotene were the maincarotenoids. Regarding the in vitro antioxidant capacity, the hydromethanolic extract of A.chica leaves was characterized as an efficient ABTS radical scavenger, in addition to protecttryptophan against oxidation by singlet oxygen in a concentration-dependent manner (IC 50 =177 μg/mL). These results stimulated the next study to further investigate the antioxidantpotential of extracts of A. chica, obtained through ultrasound-assisted extraction, using“green” solvents, against reactive oxygen (ROS) and nitrogen (RNS) species of physiologicaland food relevance. The antioxidant capacity of three extracts of A. chica leaves obtained withsolvents of different polarities (water, ethanol and ethanol/water (1:1, v/v) were tested againstsuperoxide anion radical (O 2 •- ), hydrogen peroxide (H 2 O 2 ), hypochlorous acid (HOCl), theperoxynitrite radical (ONOO−), the oxigênio singleto 1 O 2 and peroxyl radical (ROO • ). The A.chica extract prepared with ethanol/water presented the highest phenolic contents (11.80 mg/gextract), being scutelarein (flavone) the major compound (57%), while ethanol and wateralone were less efficient resulting in changes in the individual profile of phenolic compounds,highlighted by the absence of scutelarein and by the high levels of phenolic acids. All extractswere able to scavenge the tested ROS/RNS in a concentration-dependent manner with lowIC 50 values, being the extract obtained with ethanol/water the most effective for all theROS/RNS (IC 50 from 0.34 to 35.66 μg/mL). Regarding the antioxidant capacity against ROO • ,all the extracts showed the same antioxidant behavior, with scavenging efficiency about fivetimes higher than Trolox. Therefore, A. chica leaves proved to be a promising source ofbioactive compounds with high antioxidant properties to be used as natural antioxidants to inhibit oxidative damage in both food and physiological systems.
Acesso aberto (Open Access)
Discriminação da origem geográfica e quantificação de parâmetros de qualidade em sementes sementes de cacau (Theobroma cacao) cultivadas na amazônia utilizando espectroscopia no infravermelho próximo e ferramentas quimiométricas
(Universidade Federal do Pará, 2022-06-03) FERREIRA, Fabielle Negrão; OLIVEIRA, Marcos Enê Chaves; http://lattes.cnpq.br/9052059910078575; LOPES, Alessandra Santos; http://lattes.cnpq.br/8156697119235191; https://orcid.org/0000-0002-8584-5859
This work discusses the application of the Near Infrared Vibrational Spectroscopy (NIR) technique in cocoa samples from different regions of the state of Pará (Medicilandia, Tucumă and Tomé-açu) with the aim of predicting major components and discriminating these different geographic regions. The NIR technique was associated with exploratory analysis of spectral data, testing different regression and discrimination models. This research is divided into three chapters. The first chapter reviews the concepts related to the NIR technique, and explores the most diverse articles on the application of the NIR technique in cocoa for different evaluations, such as, for analysis of major components, identification of fraud and discrimination of cocoa in different regions, from the planet. In the second chapter, prediction models were developed for nitrogen, moisture and total lipids in non-fermented samples, since certain cocoa components are not altered during fermentation, so these major components of the seeds could be quickly predicted by FT spectroscopy-NIR using PLS regression. The third article presents the application of NIR associated with exploratory analysis of spectral data by principal components, for discrimination of cocoa beans under five different treatment conditions (raw, dry fermented, dry unfermented and fermented defatted), from the three different regions mentioned geographic areas, and the best results were obtained when evaluating the fermented cocoa samples from the three regions.
Acesso aberto (Open Access)
Fermentação de cacau (Theobroma cacao L.) conduzida com leveduras dos gêneros sacharomycess e pichia: qualidade e perfil aromático das amêndoas
(Universidade Federal do Pará, 2019-10-11) FERREIRA, Osienne de Sousa; LOPES, Alessandra Santos; http://lattes.cnpq.br/8156697119235191; https://orcid.org/0000-0002-8584-5859
This study aimed to evaluate the effect of Pichia manshurica, Pichia kudriavzevii and Saccharomyces cerevisiae yeasts on the quality and aromatic profile of fermented cocoa seeds from a municipality in Pará state. About 180 kg of cocoa seeds were distributed in four wooden troughs (n = 3), for spontaneous fermentation (without inoculum), with inoculations of P. manshurica, P. kudriavzevii and S. cerevisiae. Cocoa samples were aseptically collected throughout the fermentation and stored properly for microbiological and physicochemical analyzes (centesimal composition, acetic acid, ethanol, sugar profile, phenolic compounds, volatile compounds, cut test and heavy metals). It was observed that inoculations with yeast did not influence the physicochemical composition of fermented and dried seeds. However, during the fermentation process the seeds presented low acidity, especially those obtained from the fermentations inoculated with Pichia manshurica and Pichia kudriavzevii. Among the 34 volatile compounds identified in the samples studied, 5 were considered to be the majority (concentrations ≥ 10%), and 2 compounds (2-heptanol and linalol) were found to be higher in the fermentation inoculated with P. manshurica after the fermentation and drying process. followed by fermentation inoculated with P. kudriavzevii with the compounds benzaldehyde and phenylacetaldehyde. The fermentative performance of ethanol and acetic acid production was superior when fermentation inoculated with Sacharomyces cerevisiae was superior. The application of yeast inoculum influenced several quality parameters for a better standardization of the cocoa fermentation process.
Acesso aberto (Open Access)
Fermentação de cacau: processo conduzido com leveduras selecionadas, diversidade microbiológica e perfil aromático
(Universidade Federal do Pará, 2021-01-21) CHAGAS JÚNIOR, Gilson Celso Albuquerque; FERREIRA, Nelson Rosa; http://lattes.cnpq.br/3482762086356570; https://orcid.org/0000-0001-6821-6199; LOPES, Alessandra Santos; http://lattes.cnpq.br/8156697119235191; https://orcid.org/0000-0002-8584-5859
Fermented and dried cocoa beans are the raw material for the production of one of the most consumed foods worldwide: chocolate. For the formation of the essential chemical compounds for the characteristic flavors and aromas of good quality chocolate, seed fermentation is the crucial stage, where such compounds will be formed, as a result of the microbial activity developed throughout the process. A very well-defined microbial succession involving yeasts, lactic and acetic bacteria makes the fermentation medium conducive to the numerous physical and chemical reactions inside the seed, which will be finalized in the subsequent drying and roasting steps. The State of Pará is the largest Brazilian cocoa producer and stands out as a reference in the production of fermented and dried cocoa beans of excellent quality in the national and international market. To understand the role that two yeast species previously isolated and identified in cocoa fermentation in the city of Tomé-Açu play during the process, this study aimed to evaluate the addition of Saccharomyces cerevisiae and Pichia kudriavzevii starter cultures in the microbiological properties physical and chemical over the process time. The cultures of both species were reactivated and after the inoculum production, it was added to the fermentations in loco, where they were evaluated for periods of 7 days, except for the fermentation that received a mixed inoculum (equal proportions of the two species), that lasted 6 days. Over the time of the fermentations, there was a rapid consumption of total reducing sugars, an increase in temperature, a reduction in the contents of phenolic compounds, acidity and an increase in pH in treatments that received inoculations with P. kudriavzevii, in addition to providing fermented and dried cocoa beans with higher amounts of catechin and epicatechin (antioxidant activity), methylxanthines (metabolic activity), low levels of acidity and putrefactive bioactive amines such as cadaverine and putrescine. The formation of phenylethylamine was also observed in these treatments with P. kudriavzevii, showing a microbial synergy with the microbiota naturally found in fermentations. Regarding the volatile compounds identified, the amount of ketones, aldehydes and esters was higher in fermented almonds with the addition of inocula of P. kudriavzevii, which shows the importance of this yeast species in the production of volatile compounds with fruity, floral and sweets flavors. All the findings in this research are strongly linked to the existing microbiota during the fermentation of cocoa. It was possible to identify species of lactic acid bacteria that were never isolated before in cocoa fermentations in the Amazon region, which can be one of the differentials for the production of good quality cocoa beans. It was concluded that the addition of microbial inocula provided good quality fermented and dried cocoa beans, reinforcing the need for more investments in research to help rural producers in the Amazon region to emerge in the competition of the chocolate market.
Acesso aberto (Open Access)
Influência do fungo cladosporium cladosporioides no índice de qualidade e perfil aromático das amêndoas de cupuaçu (theobroma grandiflorum schum)
(Universidade Federal do Pará, 2021-12-14) LIMA, Ana Júlia Mota de; LOPES, Alessandra Santos; http://lattes.cnpq.br/8156697119235191; https://orcid.org/0000-0002-8584-5859
Cupuassu [Theobroma grandiflorum (Willd. ex Spreng.) K. Schum] is a native fruit to the Amazon region, produced on a large scale in the state of Pará. From post-harvest seed processing, it’s possible to obtain a product with a high nutritional and sensory quality similar to chocolate. The objective of this article is to present an updated review of this fruit and it’s peculiarities, detail the characteristics of the fermentation process and the microbial diversity present in the environment responsible for changes in various chemical and volatile compounds, that composes the expression of the aroma and flavor of the final product, there are only 1480 articles in the literature that generally fermentation. The keywords used for this review were: fermentation, cupuassu, cupulate, microbiology, filamentous fungi and Cladosporium cladosporioides.
Acesso aberto (Open Access)
Influência do fungo cladosporium cladosporioides no índice de qualidade e perfil aromático de sementes de cacau (Theobroma cacao L.) fermentadas
(Universidade Federal do Pará, 2020-11-17) KONAGANO, Evelyn Mayumi Hanawa; FERREIRA, Nelson Rosa; http://lattes.cnpq.br/3482762086356570; LOPES, Alessandra Santos; http://lattes.cnpq.br/8156697119235191
Cocoa is a fruit that has great scientific and economic importance. However, the existing microbial diversity between lots and locations, results in different products, in relation to physical, chemical and sensory attributes. Thus, Araujo et al. (2014) proposed variables that can be used in order to standardize the quality indices of this raw material, in addition to what is already governed by legislation. In addition, there are several studies that use starter cultures of bacteria and yeasts in the fermentation of cocoa seeds, in order to obtain beans with superior quality and desirable aromas, in addition to resulting in a more homogeneous fermented raw material between different batches and locations. However, there are still no reports of the use of filamentous fungi as a starter culture, despite having biotechnological potential, mainly due to the excretion of several enzymes. A species that has already been reported in the fermentation of cocoa seeds is Cladosporium cladosporioides, which produces antifungal metabolites aimed at plant pathogens, in addition to having pectinase, laccase, glucanase, amylase, cellulase and xylanase enzymatic activity, important for the improvement of the cocoa bean fermentation process. The objective of this study is, therefore, to evaluate the influence of this filamentous fungus during the fermentation process, in an unprecedented way, through physicochemical and microbiological analyses. For this, two fermentation experiments were carried out: without inoculum (control) and with starter culture. The use of filamentous fungus did not significantly impact the formation of aromatic compounds in the almonds, compared to the control experiment. However, the presence of C. cladosporioides had a significant influence on the percentage of well-fermented almonds (p ≤ 0.05), through the cutting test, as a probable consequence of the lower content of total phenolic compounds, and of catechin and epicatechin. In addition, there was a lower concentration of acetic acid and a higher content of bioactive amines (p ≤ 0.05), when compared to the control experiment. These observed aspects were confirmed through multivariate analysis. Based on these results, it can be said that the use of C. cladosporioides proved to be promising and could provide improvements in fermented and dried cocoa beans.
Acesso aberto (Open Access)
Leveduras da fermentação do cacau amazônico: caracterização molecular e perfil de enzimas extracelulares
(Universidade Federal do Pará, 2018-08-29) ALMEIDA, Silvana de Fátima Oiveira de; LOPES, Alessandra Santos; http://lattes.cnpq.br/8156697119235191
Scientific literature the most important step to obtain quality chocolate. The fermentation process is carried out by microorganisms naturally present in the utensils used to open the fruits, in the fermentation box and in the environment. The main microorganisms that carry out the fermentation of cacao are: yeasts, lactic and acetic bacteria. In order to obtain quality fermented almonds, it is essential to understand the role of yeasts, since these microorganisms initiate fermentation and remain throughout the process. The objective of this study was to isolate and identify the yeasts present during the cocoa fermentation and to investigate the ability of the isolated species to produce hydrolytic enzymes. The fermentations were carried out in farms, in the same way that the owners performed, both with duration of seven days and sample collection every 24 hours, for the identification of the yeasts the sequencing of the D1 / D2 region fragment of the 26S rRNA gene was carried out and amplified with universal primers for NL1GC and LS2 eukaryotes, at all fermentation times the temperature and pH of the samples were measured. A total of 44 yeast isolates were obtained from Medicilândia and 29 from Tucumã. In Medicilândia, the species Pichia manshurica and Saccharomyces cerevisiae were identified. In Tucumã five species Pichia fermentans, P. kudriavzevii, P. manshurica, S. cerevisiae and Zygosaccharomyces bailii. For the potency test in Medicilândia, 3 yeasts showed potential for the production of amylase, 10 for cellulase, 1 for lipase and 2 for proteinase, the yeasts that produced the enzymes were S. cerevisiae. In Tucumã S. cerevisiae did not produce any enzyme, the Pichia species obtained a positive result for the enzymes amylase, cellulase and phospholipase. Thus, this study proposes the importance of yeasts during cocoa fermentation, since the dominance of the Pichia and Saccharomyces genera was observed in the two localities of this research, and the production of hydrolytic enzymes from these species, which suggests that these yeasts can be used in biotechnological processes in the food industry.
Acesso aberto (Open Access)
Metaproteômica como ferramenta tecnológica para otimização dos parâmetros de fermentação do milho para formulação de pasta alimentícia
(Universidade Federal do Pará, 2023-06-05) BAHULE, Celina Eugenio; MARTINS, Luiza Helena da Silva; http://lattes.cnpq.br/1164249317889517; LOPES, Alessandra Santos; http://lattes.cnpq.br/8156697119235191
In most developing countries, maize products are often what alleviate hunger and guarantee the livelihood of the population. Fermentation is a processing medium used to soften the corn kernel, improve flavor and digestibility, and some fermented corn products are used in the belief that they have functional properties. Maize dough, obtained by fermentation, has already been reported as having a probiotic and nutraceutical effect, however, other studies discourage its consumption, justifying it by the load and diversity of microorganisms that develop during fermentation. With the aim of studying the functional profile and looking for likely ways to optimize maize dough, a recreation of the spontaneous fermentation of corn was performed, and the formulated dough was subjected to metaproteomics analysis. A total of 53977 peptides were recovered and identified, of which more than 60% were associated with the substrate, 6% with fungi, and 34% with bacteria. Metaproteomics revealed a probable association between Actinobacteria and starch degradation enzymes in the matrix. Proteobacteria (pathogenic majority) and Firmicutes (probiotic part) coexisted and multiplied in equal proportion until the end, allied to this, the high count of mesophiles(213 x 106 CFU/g) and the timid reduction of the pH (4.42) suggested a food product not completely safe. As a way to optimize the process, the maize was autoclaved at 121oC for 20 min for enzymatic inactivation and elimination of microorganisms, and then it was inoculated with Pediococcus acidilati. Untreated maize was also inoculated. The performance of the strain both in pre-treated maize (T+I) and in untreated maize (nT+I) was considered excellent, since, in the first 24 hours, the pH values, 4.2 for nT+I samples and 4.41 for T+I samples were at levels considered safe and decreased with fermentation time. The strong correlation between the fermentation parameters when P.acidilati was used for maize inoculation, opens possibilities for the application of optimization models towards the fast, safe, and industrial production of maize dough. Indeed, metaproteomics, as culture-free and protein-based technique, allows the rapid analysis of the microbiota and the identification of active microorganisms, with the advantage of displaying and correlating the microbial profile with functionality, and are well indicated to study fermented foods quickly and concisely, demonstrating effective methods for optimization
Acesso aberto (Open Access)
Otimização da pasteurização da polpa de jambolão (Syzygium cumini lamarck)
(Universidade Federal do Pará, 2014-11-21) AMÉRICO, Gilciane Vergolino; CARVALHO, Ana Vânia; http://lattes.cnpq.br/7856575452724939; LOPES, Alessandra Santos; http://lattes.cnpq.br/8156697119235191
The Syzygium cumini Lamarck fruits, popular known as jambolan, are a source of anthocyanin and antioxidant. This study aimed to optimize the thermic pasteurization of the jambolan pulp, with the purpose to inactivate the enzymes, the bioactive compounds and the antioxidant activity retention. Physical analyses: transverse length (2,49cm), longitudinal length (1,68cm) and percent yield (57,22%); and physicochemical: moisture (89.43%) ash (0.27%), lipid (0.23%), protein (0.72%), acidity (5.99% citric ac.), soluble solids (9,17 ° Brix), pH (3.34), total phenolic (182.01 mgGAE.100g-1), total anthocyanin (93.56 mg.100g-1) and antioxidant activity by DPPH method (EC50 = 4552.26 g / gDPPH) and ABTS (18,48 μMTrolox / g) were performed. Due to a resistance while trying to flow the jambolan pulp in the pasteurizer pipes, the pulp was diluted and complied with the national legislation (Brasil, 2003) for tropical juice. The methodology used was a central composite design (2²), using as independent variables: temperature (°C) and time (s), and as response variables: total phenolic compounds, total anthocyanin, antioxidant activity (DPPH and ABTS) and enzymatic activity (POD and PPO). The enzymes of the jambolan tropical juice were completely inactivated, except for POD in the test treated with 85ºC/39sec. The independent variables and the interaction of them didn’t influence significantly at 95% of confidence level in the results obtained to generate predictive models of the characteristics evaluated, except for the total phenolic content. The best condition to obtain a maximum retention of the compounds analyzed and the complete inactivation of the enzymes was the temperature 92ºC and time 70sec for tropical juice of jambolan which was pasteurized.
Acesso aberto (Open Access)
Perfil aromático e de compostos fenólicos de amêndoas de cacau fermentadas na Amazônia brasileira em diferentes temporadas do ano
(Universidade Federal do Pará, 2019-03-29) GASPAR, Daniela Pinheiro; LOPES, Alessandra Santos; http://lattes.cnpq.br/8156697119235191; https://orcid.org/0000-0002-8584-5859
Cocoa is one of the most well-known foods in the world and its sensory attributes and physicochemical characteristics define which by-product will be manufactured from it and what its market value. The Amazon has great potential for production of fine and recognized cocoa in the market, due to its important biodiversity and perception of quality allied to the products coming from this region. The complex composition of the fermented and dry cacao will depend on several factors, such as fruit genotype, environmental conditions and abiotic stress in which the cacao tree grows, soil chemical composition and post-harvest treatments, being the fermentation the primordial stage for obtaining of quality almonds. It is during the fermentation that several groups of microorganisms, like yeasts and lactic and lactic bacteria, act generating biochemical reactions that modify the interior of the cacao seeds. In this study it was verified that the season of the year in which the cocoa is fermented influenced the chemical composition and volatile profile of its fermented almonds. The temperature of the fermentative mass, pH and acidity of the seeds were influenced by the season of the year. The pH and acidity of cocoa beans were also influenced according to the season of the year because they varied during the fermentation days. The principal component analysis showed that the times 0 h and 24 h are the ones that receive the most influence of the period of the year, due to their greater variation. No significant statistical differences (p0,05) were observed in the centesimal composition of the fermented cocoa in both seasons. The total phenolic compounds and the majority of cocoa (catechin and epicatechin) decreased throughout the fermentation and were influenced by the period of the year, with an emphasis on epicatechin, which presented a significant statistical difference (p≤0.05) in dry fermented almonds. Like phenolic Compounds, methylxanthines also decayed throughout the fermentation, but there was no significant statistical difference (p0.05) between the periods of the year. The profile of volatile compounds present in cocoa fermentation and drying showed differences between the seasons of the year, and this information can be used by producers in the labeling of their products to inform the sensory perception of the present volatiles identified in this work. Volatile compounds were found in fine cocoa, such as 2-nonanone and phenylacetaldehyde, and this indicates a potential use of Amazonian cocoa for the production of fine chocolates.
Acesso aberto (Open Access)
Potencial antioxidante de compostos bioativos da chicória (eryngium foetidum L.) por métodos químicos (in vitro)
(Universidade Federal do Pará, 2022-04-29) LEITÃO, Deusa do Socorro Teixeira Costa; CHISTÉ, Renan Campos; http://lattes.cnpq.br/0583058299891937; LOPES, Alessandra Santos; http://lattes.cnpq.br/8156697119235191
Amazonian chicory (Eryngium foetidum L.), a native plant to the Amazon and Central America, is one of the main unconventional vegetables (PANCs) grown in Brazil and considered as apromising source of bioactive compounds. The main objective of this work was to determine the composition of phenolic compounds and carotenoids in amazonian chicory leaves using high performance liquid chromatography coupled to diode array detectors and mass spectrometer (HPLC-DAD-MS /MS), as well as the evaluation of the in vitro antioxidant potential. The leaves of Amazonian chicory presented high contents of water (87%), low contents of lipids (2.8%), proteins (1.99%) and low total energy value (52.23 kcal/100 g). The main phenolic compounds in the leaves were chlorogenic acid (4328 μg/g), followed by ferrulic acid derivative (3892 μg/g), while the main carotenoids were lutein (204.86 μg/g), followed by β-carotene (161 μg/g leaves). Regarding the evaluation of the in vitro antioxidant capacity, the hydromethanolic extract of Amazonian chicory leaves was able to eliminate DPPH●(91.6%, at 5 mg/mL), ABTS●+ (15.77 μM Trolox equivalent/g of extract) and exhibited high efficiency to protect tryptophan against 1O2 in a concentration-dependent manner (IC50 = 343 μg/mL). Furthermore, Amazonian chicory leaf extracts were obtained using green solvents with different polarities [H2O, EtOH/H2O, EtOH (1:1, v/v)], through ultrasound-assisted extraction. The scavenging capacity of the extracts against the main reactive oxygen (ROS) and nitrogen (RNS) species was evaluated, namely the superoxide anion radical (O2•-), hydrogen peroxide (H2O2), hypochlorous acid (HOCl), and the peroxynitrite anion (ONOO−). The EtOH/H2O extract presented the highest phenolic compound contents (5781.00 mg/g extract) and the highest scavenging efficiency, being chlorogenic acid the major compound (38%). All the extracts were efficient in scavenging all the tested ROS and RNS in a concentration-dependent manner. The EtOH/H2O extract was the most effective (IC50 of 45.00 – 1000 μg/mL) for almost all species, with the exception of 1O2. Regarding ROO•-scavenging capacity, the most efficient extract was EtOH. Based on the results of this study, the green solvents used in this study were promising for obtaining amazonian chicory leaf extracts with a high content of bioactive compounds and antioxidant capacity. Therefore, such information have great relevance for the food, cosmetic and pharmaceutical industries, since amazonian chicory is a natural rich source of bioactive compounds to be used as potential raw material for obtaining extracts against oxidative damage both in food and physiological systems.
Acesso aberto (Open Access)
Principais compostos bioativos e capacidade antioxidante da polpa do camu-camu (Myrciaria dubia) em diferentes estádios de maturação
(Universidade Federal do Pará, 2014-06-25) OLIVEIRA, Thaise Cristine de Souza; MATTIETTO, Rafaella de Andrade; http://lattes.cnpq.br/7832266671782588; LOPES, Alessandra Santos; http://lattes.cnpq.br/8156697119235191
This study aimed to determine physical and physico-chemical characteristics, bioactive compounds and antioxidant capacity from camu-camu pulp of three different progenies, came from Active Germplasm Bank of camucamuzeiro, at Embrapa Amazônia Oriental, in three ripening stages. Over the ripening, the mass and the diameters varied (p ≤ 0.05) just for progeny 44 and the pulp yield increased for all the progenies, with results over 50% in the ripe stage. The ripening stage didn’t show effects in the moisture and ashes content and also pH for progeny 38; ashes for progeny 44 and fat and insoluble fibers for progeny 17. The others results varied with the ripening, but, with different behaviors to each progeny, except for the total sugar, soluble solids contents and the SS/TTA ratio, which showed a tendency to increase, and the total titratable acidity decreased in all the progenies. Overall, a higher level of vitamins C were obtained in the green stage, with a first step of degradation, as it reached the semi-ripe stage, followed by a synthesis step until the end of the ripening stage, except for the progeny 38, which showed a reduction. As for the phenolic compounds, during the ripening stage, the three progenies were characterized for synthesis and degradation processes of the total phenolic compounds; the total flavanols decreased; the flavonols content had a distinct behavior in each progeny, with an increasing in the progenies 17 and 38, and a decreasing in the progeny 44; due to a limitation of the method used to determine small quantities, It was possible to quantify anthocyanins only for progenies 17 and 44 in the ripening stage. The antioxidant capacity, determinated through the methods TEAC and DPPH, decreased in all the progenies. Besides the significant effects of the ripening stage, the results showed that the genetic variability of camu-camu influenced significantly the physical characteristics of the fruits and the continents of all compounds studied, and still the antioxidant capacity obtained through the methods mentioned.
Acesso aberto (Open Access)
Principais compostos bioativos e capacidade antioxidante no epicarpo do camu-camu (Myrciaria dubia) em função da maturação
(Universidade Federal do Pará, 2014-06-25) SOUZA, Aline Ozana de; MATTIETTO, Rafaella de Andrade; http://lattes.cnpq.br/7832266671782588; LOPES, Alessandra Santos; http://lattes.cnpq.br/8156697119235191
The presence of bioactive compounds suffers greatly influenced by environmental and genetic factors, and behave differently in each part of the plant. However, there are few studies which deal these aspects of camu-camu. Thus, this study aimed to analyze the physical, physico-chemical composition, the main bioactive compounds and antioxidant capacity of camu-camu bark, depending on the stage of ripeness in fruits of different genotypes from plant matrices Bank Active Germplasm Camucamuzeiro of Embrapa Eastern Amazon. Fruits of three genotypes, selected at random in three maturity stages were collected. Results were expressed on a dry basis and analyzed by Analysis of Variance, Comparison Test Tukey's and Pearson's Correlation Coefficient, with a confidence interval of 95%. For physico-chemical analysis, there was a different one for each progeny, depending on maturity, except that the carbohydrate content increased in all progenies behavior. For vitamin C, the progenies 38 and 44 showed a high content of ascorbic acid, comparing the green and ripe stages, and 17 progeny showed a decrease during maturation; the highest content of vitamin C has been found in 44 progeny, ripe stage (24,02 g/100g). All progenies showed an increase in the content of total phenolics and anthocyanins throughout maturation, with the highest values were demonstrated by progeny 17 (3298,98 AGE/100g mg) and 44 (165,91 mg/100g) respectively. Flavonols and carotenoids showed a distinct and statistically different behavior in each progeny, with the highest content of flavonols was found in 17 progeny in the green stage (343,63 mg QE/100g) and carotenoids in 44 progeny, ripe stage (105,88 mg/100g). Regarding the antioxidant activity based on the DPPH method, the progenies 38 and 44 showed the same behavior throughout maturation, with higher antioxidant activity half ripe and smallest stage in green, with the highest antioxidant activity was found in 17 progeny in the ripe stage (38,95 g fruit/g). Already by ABTS method, the antioxidant activity was statistically different for all progenies and in all stages of maturation, higher value submitted by 44 progeny at maturity (170,63 μM trolox/g). Evaluating the relationship between bioactive compounds and antioxidant activity, the 17 progeny won more statistically significant correlations. It can be concluded that various factors cause differences in the synthesis of various compounds during fruit ripening of camucamuzeiro.
Acesso aberto (Open Access)
Revestimento comestível incorporado com tocoferóis e aplicação em Castanhado-Brasil (bertholletia excelsa bonpl.) para monitoramento do perfil de oxidação lipídica
(Universidade Federal do Pará, 2024-02-29) COSTA, Danusa Silva da; TAKEUCHI, Katiuchia Pereira; http://lattes.cnpq.br/1724899631394370; https://orcid.org/0000-0002-0731-8279; LOPES, Alessandra Santos; http://lattes.cnpq.br/8156697119235191; https://orcid.org/0000-0002-8584-5859
Brazil nuts are a non-timber product of great importance to extractivist families. They contain many nutrients and are rich in lipids. However, from collection to oil extraction, Brazil nuts are exposed to various degrading conditions such as humidity, light, and heat due to exposure to the environment, and these conditions can intensify the lipid oxidation of this product. For this reason, developing an active coating is an alternative for protecting and preserving Brazil nuts from lipid oxidation. The aim was to develop an active edible coating incorporated with tocopherols and apply it to Brazil nuts to monitor their lipid oxidation profile at different storage times. Films were prepared by casting. Four blends, called B, L, LT, and LT2, were prepared using fixed amounts of cassava starch + carboxymethyl cellulose + sorbitol and water (3 g + 1.5 g + 0.2 g + 100 g, respectively), soy lecithin was added in a proportion of 20% in relation to the tocopherol mix, formulation L was prepared with the same amount of lecithin as LT2. The amount of tocopherol mix was added to the mixtures in the following proportions: B - 0, L - 0, LT - 0.0005 g, and LT2 - 0.010 g. Tests were carried out on thickness, water solubility, water content, weight, contact angle, permeability, mechanical tests, antioxidant activity, biodegradability, color, thermogravimetry, and FTIR. The films were characterized as biodegradable, antioxidant, and hygroscopic and suitable for application as a coating on Brazil nuts. Viscosity, creaming index, centrifugation, pH, and color of the solutions forming the coatings were evaluated, making it possible to characterize the blends as a non-Newtonian and highly stable pseudoplastic fluid. The Brazil nuts were immersed in the coating-forming solutions, dried at 45°C for 19 hours, stored at 25°C, and evaluated at 1, 7, 15, 30, 45, 60, 90, and 120 days of storage. By official methods, tests were carried out on mass loss, browning index, conjugated dienes and trienes, oxidative status, and accelerated oxidation index. All the coatings applied minimized oxidation at some stage during storage. However, the coatings added with the tocopherol mix minimized dienes, trienes, the iodine index, the peroxide index, p-anisidine, and the total oxidation index. The accelerated oxidation test showed that the nut oil under study underwent some changes in its oxidative state, although the use of the coatings largely preserved them. The models applied to the accelerated oxidation test data made it possible to estimate the half-life of the Brazil nuts, so it was found that the LT coating showed a value of 129.86h for the half-life time in the firstorder model. The principal component analysis (PCA) applied to the physicochemical characterization data and the induction time revealed that the oil from nuts uncoated presented itself in isolation as being extremely influenced by the oxidative indices evaluated, presenting an explained variability of the data greater than 75% in most of the storage times. PCA also showed that the oil from Brazil nuts coated with LT and LT2 was negatively influenced by most of the oxidative indices, in which case this is an advantage, as it demonstrates lower rates of lipid oxidation in these samples. Developing a film with antioxidant properties and applying it as a coating on Brazil nuts made it possible to verify some levels of protection for the nuts. We suggest applying the blends developed as a film or active coating to other food products that need protection against light and oxidation.

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