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Percorrer EM - Artigos Científicos por Domínios Científicos e Tecnológicos (FOS) "Ciências Agrárias::Biotecnologia Agrária e Alimentar"
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- Impact of five basic tastes perception on neurophysiological response : results from brain activityPublication . Pereira, Diana Rico; Pereira, Helena Rico; Silva, Maria Leonor; Pereira, Paula; Ferreira, Hugo AlexandreThe five basic tastes (sweet, salty, umami, sour, and bitter) perception plays a fundamental role in food choices. Nevertheless, how the perception of each basic tastes influence brain activity is still unknown. We investigated the effect of each taste on the brain activity of healthy adults using electroencephalography (EEG). For that, sucrose, sodium chloride, sodium glutamate, citric acid, and caffeine solutions were individually administered to 28 participants (18–25 years old). Self-reporting feedback was assessed using the 3-dimensional Self-Assessment-Manikin (SAM). The power density of the five frequency bands (delta, theta, alpha, beta and gamma) computed from the EEG signals was used to compare the five basic tastes. Significant differences (p < 0.05) were found for (1) beta waves: sweet vs umami, and salty vs umami; and for (2) gamma waves: sweet vs umami, and sweet vs bitter. The findings also indicate that sweet taste stimulated higher brain activity than umami in the gamma but not in the beta waves. Sweet, salty, umami and bitter tastes correlated with SAM responses. This study advances the understanding of brain response to taste stimuli, whilst improving the knowledge of these sensorial cognitive processes. Clinical trial Identifier: NCT06051175
- Impact of the use of cryoprotectants in the production of freeze-dried soluble coffee from cold brew arabica coffeePublication . Barroso, Livia Alves; Viegas, Cláudia; Stančiauskaitė, Monika; Macedo, Ana S.; Lemos, Iara Lopes; Costa, Joyce Maria Gomes da; Schmiele, Marcio; Silveira, João Vinícios Wirbitzki da; Brandão, Pedro; Amaral, Tatiana Nunes; Fonte, PedroCold brew is a method of coffee extraction that uses low temperature, preserving the volatile compounds of coffee. Freeze-drying allows the preservation of coffee features and nutritional value. The aim of this study was to evaluate the effects of different cryoprotectants in cold brew extracts as a basis for freeze-dried coffee production. Thus, the Coffea arabica extracts and the soluble coffee were characterized concerning caffeine content, antioxidant capacity, total phenolic compounds, and antimicrobial activity to verify the potential of this method. The extracts did not show antimicrobial activity with a high soluble solid content. It was observed that the cold extraction methods were efficient regarding the caffeine content, antioxidant capacity, and total phenolic compounds. Freeze-dried coffees also did not show antimicrobial activity, and they maintained the water and humidity activity standards. In general, cryoprotectants displayed an unfavorable influence on the extract and freeze-dried coffee in the analyses performed. The coffee extract without cryoprotectants had a higher antioxidant capacity (88.12%) and content of phenolic compounds (7.74 mg AG/mL of the coffee extract). Only for the analyses of soluble solids, the cryoprotectants mannitol and fructose showed promising results (14.03 °Brix, 14.40 °Brix, 11.33 °Brix, respectively). Thus, for the analyses conducted, the cryoprotectants did not lead to significant advantages for this process.
- Improving product safety for edible insects : toxicokinetics of Hg in Tenebrio molitor and Hermetia illucensPublication . Cardoso, Diogo N.; Silva, Ana Rita R.; Morgado, Rui G.; Mostafaie, Amid; Pereira, Andreia; Pinto, José; Lopes, Ivã G.; Murta, Daniel; Soares, Amadeu M. V. M.; Brooks, Bryan W.; Loureiro, SusanaSustainability, circularity, and Zero Waste policies are timely concepts for policy development and strategies in the European Union (EU) and other global regions. Insects can likely become key players in the bioconversion of waste to valuable material and promise one solution to achieve diverse societal goals. Insects further present strategic opportunities as food products; however, it is necessary to understand how insects accumulate and eliminate priority contaminants from different substrates where they can be reared. In the present study, we expanded beyond previous work with mercury (Hg) to examine bioaccumulation kinetics in Tenebrio molitor (YMW) and Hermetia illucens (BSF). Two-phase bioaccumulation assays, with an uptake (contaminated Hg substrate) and elimination phase (clean substrate), followed by toxicokinetic modeling, showed that both insects have a high capacity to regulate Hg, often reaching an internal steady-state concentration at level responding on the substrate concentration of Hg. Of importance for product safety, both insects quickly eliminated Hg after being transferred to clean substrate. Specifically, BSF eliminated half of the accumulated Hg in approximately 1 day (after 5 days of Hg exposure) and YMW in 4–5 days (after 21 days of Hg exposure). These results provide crucial product safety information for insect producers using possibly contaminated substrates, specifically informing the amount of time for Hg depuration prior to processing and commercialization for food and feed.
- Measuring minerals in pseudocereals using inductively coupled plasma optical emission spectrometry : what is the optimal digestion method?Publication . Nascimento, Ana C.; Motta, Carla; Rego, Andreia; Delgado, Inês; Santiago, Susana; Assunção, Ricardo; Matos, Ana Sofia; Santos, Mariana; Castanheira, IsabelPseudocereals have gained attention due to their adaptability to different climates, high nutritional value, and suitability for gluten-free and plant-based diets. However, a challenge lies in the necessary adaptations in the diet pathways, mainly due to the lack of matrix-matching metrological tools. To address this problem, we developed a classification system to support laboratory decisions without shaped Proficiency Testing (PT) or Certified/Standard References Material. This system evaluates method performance through limit of detection (LOD), maximum uncertainty, and statistical comparison. For that matter, the mineral contents (Cu, Mn, Fe, Zn, Mg, P, Ca, K, and Na) of quinoa (Chenopodium quinoa), amaranth (Amaranthus caudatus), and buckwheat (Fagopyrum esculentum) were determined, using three different digestion methods, including dry-ashing, microwave, and graphite block acid digestion. A decision was reached concerning the optimal digestion method to be employed, with the results classified into three categories: (i) “rejected if results failed in two categories; (ii) “use with caution” if results were not satisfactory in one category; or (iii) “accepted”, if the results passed in all the categories. The system efficacy was exemplified by the effectiveness of dry-ashing and graphite block acid digestion by comparison with microwave digestion. Neither dry-ashing nor graphite block acid digestion can be recommended as an alternative method to the microwave digestion method when all the prioritized nutrient minerals are understudied. Although the microwave method is preferable for multi-elemental analysis, it is possible to obtain, with caution, comparable results from all the digestion methods if a higher relative combined uncertainty is defined (target uncertainty < 11%) under the assumption that this is suitable for the study.
- NaCl elicitation enhances metabolite accumulation and stress resilience in Inula crithmoides L. shoot cultures : implications for its nutritional and medicinal valuePublication . Rodrigues, Maria João; Neng, Nuno; Custódio, LuísaThis study explored the impact of sodium chloride (NaCl) elicitation on the accumulation of primary and secondary metabolites and the oxidative stress responses of Inula crithmoides L. (golden samphire) in vitro shoot cultures. Elicitation involved applying different concentrations of NaCl (0, 50, 100, and 200 mM) for 4 weeks. This was followed by assessing its impact on plant growth, physiological parameters (pigments, hydrogen peroxide content, total soluble sugars and proteins, and proline), and secondary metabolism (phenylalanine ammonia-lyase activity, shikimic acid, phenolics, flavonoids, and hydroxycinnamic acids) in the shoots. The extracts were also analysed using high-performance liquid chromatography (HPLC). The NaCl elicitation did not affect shoot growth but increased physiological functions such as photosynthesis and oxidative stress management under moderate salinity levels. In addition, NaCl treatments increased the synthesis of soluble sugars and proteins, particularly proline, as well as bioactive phenolics such as gentisic acid, chlorogenic acid, 4-hydroxybenzoic acid, luteolin-7-O-glucoside, and naringenin-7-O-glucoside. The NaCl elicitation in golden samphire shoot cultures offers a significant method for enhancing the production of important nutritional and bioactive compounds. This underscores the species’ potential for cultivation in saline environments and provides valuable prospects for its utilization in the health and nutrition sectors.
- Nitrite quantification in processed meat using an enzyme biosensor, a portable reader and a smartphone : a facile and accurate approachPublication . Surace, Luca; Zumpano, Rosaceleste; Polli, Francesca; Gajdar, Július; Mazzei, Franco; Almeida, M. GabrielaThe control of nitrite levels in foodstuff is essential for ensuring human safety. However, the protocols are long and require lab equipment (spectrophotometer and centrifuge) not available in industrial or commercial settings. Herein, we adapted an electrochemical nitrite biosensor utilizing the enzyme cytochrome c nitrite reductase (ccNiR) previously developed in our lab, to meet the analytical requirements of cured meats, and validated it using real samples from different brands. The enzyme was immobilized on a disposable carbon screen-printed electrode (SPE) modified with multi-walled carbon nanotubes (MWCNTs) and connected to a hand-held potentiostat coupled to a smartphone. The carbon nanotubes suspension was optimized using chemically friendly solvents and the SPE surface was electrochemically characterized using ferricyanide as a redox probe, to fine-tune the modification formulation. The nitrite biosensor delivered a sensitivity of 0.0103 μA/μM, a linear range from 5 to 100 μM, and a lower detection limit (LOD) of 3.2 μM. Subsequently, the biosensor was tested for its ability to detect nitrites in various processed meat samples, considering factors such as type and origin. The validation of the electrochemical biosensor was conducted using the gold standard Griess method and HPLC, although the first one failed to detect nitrites in some samples due to matrix interferences. Accordingly, the nitrite biosensor performed well, providing highly accurate and precise results (smaller SD), even in non-centrifuged samples, making it possible to control the meat quality at any point of the chain distribution.