Exploring the Impact of α-Amylase Enzyme Activity and pH on Flavor Perception of Alcoholic Drinks.

The introduction of a drink in the mouth and the action of saliva and enzymes cause the perception of basic tastes and some aromas perceived in a retro-nasal way. Thus, this study aimed to evaluate the influence of the type of alcoholic beverage (beer, wine, and brandy) on lingual lipase and α-amylase activity and in-mouth pH. It was possible to see that the pH values (drink and saliva) differed significantly from the pH values of the initial drinks. Moreover, the α-amylase activity was significantly higher when the panel members tasted a colorless brandy, namely Grappa. Red wine and wood-aged brandy also induced greater α-amylase activity than white wine and blonde beer. Additionally, tawny port wine induced greater α-amylase activity than red wine. The flavor characteristics of red wines due to skin maceration and the contact of the brandy with the wood can cause a synergistic effect between beverages considered "tastier" and the activity of human α-amylase. We can conclude that saliva-beverage chemical interactions may depend on the saliva composition but also on the chemical composition of the beverage, namely its constitution in acids, alcohol concentration, and tannin content. This work is an important contribution to the e-flavor project, the development of a sensor system capable of mimicking the human perception of flavor. Furthermore, a better understanding of saliva-drink interactions allow us to comprehend which and how salivary parameters can contribute to taste and flavor perception.

Exploring the Biofilm Formation Capacity in S. pseudintermedius and Coagulase-Negative Staphylococci Species.

The ability of biofilm formation seems to play an important role in the virulence of staphylococci. However, studies reporting biofilm formation of coagulase-negative staphylococci isolated from animals are still very scarce. Thus, we aimed to evaluate the biofilm-forming capacity of CoNS and S. pseudintermedius isolated from several animal species and to investigate the effect of conventional antimicrobials on biofilm reduction. A total of 35 S. pseudintermedius and 192 CoNS were included. Biofilm formation was accessed by the microtiter plate assay and the biofilms were stained by crystal violet. Association between biofilm formation and staphylococci species and antimicrobial resistance was also performed. Biofilm susceptibility testing was performed with tetracycline and amikacin at the minimum inhibitory concentration (MIC) and 10 × MIC. The metabolic activity of the biofilm cells after antimicrobial treatment was accessed by the XTT assay. All isolates formed biofilm, with S. urealyticus producing the most biofilm biomass and S. pseudintermedius producing the least biomass. There was a positive association between biofilm formation and multidrug resistance as well as resistance to individual antimicrobials. Neither tetracycline nor amikacin were able to eradicate the biofilm, not even at the highest concentration used. This study provides new insights into biofilm formation and the effects of antimicrobials on CoNS species.

Biofilm Formation of Staphylococcus aureus from Pets, Livestock, and Wild Animals: Relationship with Clonal Lineages and Antimicrobial Resistance.

This study aimed to compare the biofilm formation ability of Staphylococcus aureus isolated from a wide range of animals and study the association between biofilm formation and antimicrobial resistance and genetic lineages. A total of 214 S. aureus strains isolated from pets, livestock, and wild animals were evaluated regarding their ability to form biofilms by the microtiter biofilm assay and their structure via confocal scanning laser microscopy. Statistical analysis was used to find an association between biofilm formation and antimicrobial resistance, multidrug resistance, sequence types (STs), spa and agr-types of the isolates. The antimicrobial susceptibility of 24 h-old biofilms was assessed against minimum inhibitory concentrations (MIC) and 10× MIC of amikacin and tetracycline, and the biomass reduction was measured. The metabolic activity of biofilms after antimicrobial treatment was evaluated by the XTT assay. All isolates were had the ability to form biofilms. Yet, significant differences in biofilm biomass production were detected among animal species. Multidrug resistance had a positive association with biofilm formation as well as methicillin-resistance. Significant differences were also detected among the clonal lineages of the isolates. Both tetracycline and amikacin were able to significantly reduce the biofilm mass. However, none of the antimicrobials were able to eradicate the biofilm at the maximum concentration used. Our results provide important information on the biofilm-forming capacity of animal-adapted S. aureus isolates, which may have potential implications for the development of new biofilm-targeted therapeutics.

Structural Equation Modeling (SEM) and Temporal Dominance of Sensations (TDS) in the Evaluation of DOC Douro Red Wine's Sensory Profile.

In the Portuguese Douro region, several DOC (Denomination of Controlled Origin) Douro red wines are produced and, due to the peculiar characteristics of the three Douro sub-regions, present particular imprinted terroirs, that can be perceived when tasted. Considering the DOC Douro wine's sensory profile and terroir, this study aimed to analyze the sensory characteristics of red wines produced in the three Douro sub-regions (Baixo Corgo, Cima Corgo, and Douro Superior) by a single point sensory technique, a Quantitative Descriptive Analysis-QDA® and also applying a temporal method-TDS (Temporal Dominance of Sensations). The use of QDA and TDS methods proved to be efficient in the wine's sensory profile characterizing. The QDA® method allowed a detailed classification of attributes; however, the TDS method proved to be much more efficient. Moreover, the wines of the three sub-regions presented profiles with characteristics very similar in olfactory and taste/flavor aspects, pointing out a huge relation between the characteristics of the three sub-regions and the grape varieties present in the wines. Globally, the olfactory profile of wines is characterized by Fruity, Floral, and Balsamic aromatic notes, while the taste/flavor profile stands out, highlighting Astringency and Acidity and, again, Fruity as the main in-mouth aroma. It was also possible to conclude that TDS is a fast method that is easy to apply and has excellent results in the evaluation of the olfactory and taste/flavor profile of wines and, with a larger set of samples, it would be possible to obtain characteristic TDS curves for each Douro sub-region, providing a wine's fingerprint that could be used for authentication and traceability purposes.

An Overview of Sensory Characterization Techniques: From Classical Descriptive Analysis to the Emergence of Novel Profiling Methods.

Sensory science provides objective information about the consumer understanding of a product, the acceptance or rejection of stimuli, and the description of the emotions evoked. It is possible to answer how consumers perceive a product through discriminative and descriptive techniques. However, perception can change over time, and these fluctuations can be measured with time-intensity methods. Instrumental sensory devices and immersive techniques are gaining headway as sensory profiling techniques. The authors of this paper critically review sensory techniques from classical descriptive analysis to the emergence of novel profiling methods. Though research has been done in the creation of new sensory methods and comparison of those methods, little attention has been given to the timeline approach and its advantages and challenges. This study aimed to gather, explain, simplify, and discuss the evolution of sensory techniques.

Use of Parabens (Methyl and Butyl) during the Gestation Period: Mitochondrial Bioenergetics of the Testes and Antioxidant Capacity Alterations in Testes and Other Vital Organs of the F1 Generation.

Since the mid-1920s, parabens have been widely used as antimicrobial preservatives in processed foods and beverages, pharmaceuticals, and cosmetic products. Paraben use continues to generate considerable controversy, both in the general population and in the scientific community itself. The primary purpose of our study was to determine whether parabens (methyl and butyl at concentrations of 100 and 200 mg/kg body weight by subcutaneous injection) during pregnancy of adult female Wistar rats can have an impact on the F1 generation. As far as we know, we are the first to demonstrate that using parabens during pregnancy has negative repercussions on the mitochondrial bioenergetics and antioxidant activity of testicular germ cells in the F1 generation. Our study showed that there was a 48.7 and 59.8% decrease in the respiratory control index with 100 and 200 mg/kg of butylparaben, respectively. Cytochrome c oxidase activity was significantly inhibited (45 and 51%) in both groups. In addition, 200 mg/kg butylparaben promoted a marked decrease in citrate synthase activity, indicating that mitochondrial content decreased in the germ cells, especially spermatocytes and spermatids. Mitochondrial ROS production increased in groups exposed to parabens in a concentration-dependent manner, especially the butyl one (102 and 130%). The groups exposed to butylparaben showed an increase in superoxide dismutase (SOD) and catalase (CAT) activities, while glutathione reductase (GR) and glutathione S-transferase (GST) decreased. With methylparaben, only differences in SOD and GR were observed; for the latter, this only occurred with the highest concentration. The glutathione (GSH)/glutathione disulfide (GSSG) ratio did not undergo any significant change. However, there was a considerable increase in hydroperoxide content in animals exposed to butylparaben, with 100 and 200 mg/kg resulting in 98.6 and 188% increase, respectively. Furthermore, several other organs also showed alterations in antioxidant capacity due to paraben use. In summary, our study demonstrates that paraben use during pregnancy will cause severe changes in the mitochondrial bioenergetics and antioxidant capacity of testicular germ cells and the antioxidant capacity of several other F1 generation organs.

Creation and Acceptability of a Fragrance with a Characteristic Tawny Port Wine-Like Aroma.

Port wine, the ultimate expression of the Demarcated Douro Region's (DDR's) history, cultural heritage experience, and art, was born on the slopes of the Douro river valley. One of the categories of port wine that is much appreciated by consumers is tawny port wine. This category of wine is aged in oak barrels and is characterized by oxidative aromas. Thus, the objective of the present work was to develop a tawny port wine-like fragrance, the first according to the literature. First, a group of 50 consumers in an informal environment and using two samples of tawny port wine (13 and over 40 years of aging in wood, respectively) was asked about the pleasantness of the aromas and the possible use of a tawny port wine-like fragrance. More than 80% of the group stated that they would use the fragrance as an air freshener (scent marketing in restaurants) or even in personal-use products. Then, a sensory panel of 12 participants (3 men and 9 women) was trained, and using tawny port wines of various brands and ages, the panel selected six descriptors to aromatically describe this type of wine. For the descriptors, seven aromatic chemical compounds were appointed and fragrances were developed with contributions from the panel. After several sessions with the sensory panel, three fragrances were selected, created with only three of the aromatic compounds initially used: benzaldehyde, sotolon, and vanillin. Afterward, the levels of consumer acceptability (150 individuals) for the three developed fragrances were studied and the optimization of their sensory characteristics was evaluated using a "just about right" (JAR) scale. It was found that male individuals assigned higher ratings and preferred fragrance 5.1, which was a statistically significant result (p < 0.001). Regarding age, Tukey's test showed significant differences in responses to fragrance 5.3 between young adults and middle-aged adults (p = 0.018). Young adults gave higher scores for this fragrance. Additionally, consumers considered that the intensity of the tawny port wine aroma was ideal in the three fragrances, however, the fragrance color was not very intense. The use of the three compounds (benzaldehyde, sotolon, and vanillin) seems to be enough to obtain a tawny port wine-like fragrance.

Beverage and Food Fragrance Biotechnology, Novel Applications, Sensory and Sensor Techniques: An Overview.

Flavours and fragrances are especially important for the beverage and food industries. Biosynthesis or extraction are the two main ways to obtain these important compounds that have many different chemical structures. Consequently, the search for new compounds is challenging for academic and industrial investigation. This overview aims to present the current state of art of beverage fragrance biotechnology, including recent advances in sensory and sensor methodologies and statistical techniques for data analysis. An overview of all the recent findings in beverage and food fragrance biotechnology, including those obtained from natural sources by extraction processes (natural plants as an important source of flavours) or using enzymatic precursor (hydrolytic enzymes), and those obtained by de novo synthesis (microorganisms' respiration/fermentation of simple substrates such as glucose and sucrose), are reviewed. Recent advances have been made in what concerns "beverage fragrances construction" as also in their application products. Moreover, novel sensory and sensor methodologies, primarily used for fragrances quality evaluation, have been developed, as have statistical techniques for sensory and sensors data treatments, allowing a rapid and objective analysis.

Structural Equation Modelling (SEM) applied to sensory profile of Vinho Verde monovarietal wines.

Vinho Verde is the biggest DOC of Portugal, and it produces wines distinguished by their high acidity and flavor. In this Portuguese wine-region, three grape varieties, Alvarinho, Loureiro, and Arinto, are used to produce monovarietal wines of great quality. Sensory characterization of wines has the aim of detecting unique qualities in wines, and the most common measurement for the sensory aspects of wines sensory profile is descriptive sensory analysis, typically performed by trained sensory panels. To a list of attributes that can characterize a wine, we call a "sensory lexicon" that can be used by marketers allowing the articulation of flavor perceptions to consumers. So, the aim of this work was to recruit and train a sensory panel able to describe the sensory aspects associated with the monovarietal wines from Loureiro, Arinto and Alvarinho grape-varieties. Furthermore, a second order factor analysis statistical model was developed for each grape-variety wine, based on the data-set of sensory attributes, allowing a new perspective in the sensory characterization of these wines. We discover that there are some similarities between the sensory lexicons that can be used to better describe the wines. However, there are descriptors that specify each monovarietal wine. Loureiro wines present "Loureiro and mineral aromas"; Alvarinho wines are described by having "citrus" aroma and freshness in the mouth and Arinto wines possess a distinctive fruity aroma (peach and pineapple) with an alcoholic, acid and fresh flavor. Additionally, it was also shown that Structural Equation Modelling (SEM) is a worthy statistical tool to be used in sensory analysis data treatment.

Atividades práticas no ensino médio: uma abordagem experimental para aulas de genética / Practical activities in high school education: an experimental approach to genetics teaching

A experimentação no ensino se faz necessária para aproximar os alunos dos fenômenos ensinados nas aulas teóricas, no entanto, as atividades práticas são pouco utilizadas por professores de ciências e biologia. Além disso, os alunos apresentam dificuldades para compreender os conceitos e o fato de os professores utilizarem apenas aulas expositivas baseadas nos livros e apostilas, que trazem exemplos distantes do cotidiano, agrava o problema. Diante desses argumentos, o objetivo deste trabalho foi, por meio de um estudo exploratório, propor um cruzamento monohíbrido, utilizando como material a mosca Drosophila melanogaster como estratégia didática no complemento dos princípios mendelianos para alunos do 2º ano do ensino médio. A atividade foi desenvolvida em horário extra aula, com 10 alunos voluntários, teve duração de sete semanas, sendo uma aula por semana, e contemplou, além do cruzamento, leitura de textos complementares, exercícios de probabilidade, debate sobre a importância da ética no uso das aplicações da genética e fases do ciclo de vida do inseto. O desempenho dos alunos foi avaliado através de um questionário aplicado antes e após as atividades. Os principais resultados indicam que a atividade prática auxiliou na promoção da integração dos alunos e na evolução do entendimento sobre os conteúdos estudados.

Atividades práticas no ensino médio: uma abordagem experimental para aulas de genética / Practical activities in high school education: an experimental approach to genetics teaching

A experimentação no ensino se faz necessária para aproximar os alunos dos fenômenos ensinados nas aulas teóricas, no entanto, as atividades práticas são pouco utilizadas por professores de ciências e biologia. Além disso, os alunos apresentam dificuldades para compreender os conceitos e o fato de os professores utilizarem apenas aulas expositivas baseadas nos livros e apostilas, que trazem exemplos distantes do cotidiano, agrava o problema. Diante desses argumentos, o objetivo deste trabalho foi, por meio de um estudo exploratório, propor um cruzamento monohíbrido, utilizando como material a mosca Drosophila melanogaster como estratégia didática no complemento dos princípios mendelianos para alunos do 2º ano do ensino médio. A atividade foi desenvolvida em horário extra aula, com 10 alunos voluntários, teve duração de sete semanas, sendo uma aula por semana, e contemplou, além do cruzamento, leitura de textos complementares, exercícios de probabilidade, debate sobre a importância da ética no uso das aplicações da genética e fases do ciclo de vida do inseto. O desempenho dos alunos foi avaliado através de um questionário aplicado antes e após as atividades. Os principais resultados indicam que a atividade prática auxiliou na promoção da integração dos alunos e na evolução do entendimento sobre os conteúdos estudados.