ESAV - DIA - Artigo em revista científica, indexada ao WoS/Scopus
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- Agricultura familiar e proteção das culturas: abordagens tradicionais e proximidade com práticas de agricultura biológicaPublication . Costa, Cristina Amaro Da; Guiné, Raquel; Esteves Correia, Helena; Costa, Daniela; Costa, Telmo; Parente, Cristina; Pais, Celso; Gomes, Mafalda; Aguiar, AnaDesde há quase um século, a proteção das culturas em explorações agrícolas familiares, tem vindo a juntar às práticas tradicionais, meios de proteção curativos para combater pragas, doenças e infestantes, em particular recorrendo ao uso de pesticidas. Estes agricultores assumem grande relevância territorial, económica e social em Portugal e a sociedade procura os seus produtos, em mercados e feiras locais, por entender que estão associados a práticas agrícolas com menores impactos na saúde e no ambiente e se aproximam do modo de produção biológico. Assim, procura-se identificar as práticas agrícolas da agricultura familiar, na componente de proteção das culturas, que podem ter impactos negativos no ambiente e na saúde humana e que se distanciam da agricultura biológica. A partir de um questionário (cheklist), aplicado a 125 agricultores familiares com explorações situadas em Portugal (Viseu, Braga e Barcelos) e Espanha (Pontevedra e Padron), identificaram-se as práticas agrícolas relacionadas com a proteção das culturas. Identificaram-se algumas práticas comuns com a agricultura biológica: diversidade cultural, consociações, rotação de culturas, seleção de variedades resistentes. Outras, como o pousio, intervenções em verde ou luta biotécnica, são utilizadas apenas por alguns agricultores familiares. Por outro lado, a luta química é utilizada pela maioria dos agricultores familiares.
- An Insight into the Level of Information about Sustainability of Edible Insects in a Traditionally Non-Insect-Eating Country: Exploratory StudyPublication . Guiné, Raquel P. F.; Florença, Sofia De Guiné E; Anjos, O.; Correia, Paula; Ferreira, Bruno; Costa, Cristina Amaro DaInsects have been reported as a possible alternative solution to help feed the growing world pop-ulation with less stress on the planet, thus contributing to the preservation of the environment and natural ecosystems. However, the consumption of edible insects (EIs), although culturally ac-cepted for some communities, is not readily accepted for others. Hence this work explores the lev-el of information that people in a traditionally non-insect-eating country have about the sustaina-bility issues related with EIs, and also some possible reasons that could motivate their consump-tion. The study was based on a questionnaire survey and the results were explored by descriptive statistic tools, tree classification analysis, factor analysis and cluster analysis. The results showed that the level of information is still low in general, with most people not manifesting an opinion. However, some aspects are relatively familiar to the participants (88.9% know that the ecological footprint of insects is smaller than other meats and 86.9% know that they efficiently convert or-ganic matter into protein). Factor and cluster analysis showed three classes: cluster 1—people not informed about the facts disclosed through the true statements and also not able to distinguish the false information; cluster 2—people not informed about the facts disclosed through the true statements but who were able to distinguish the false information; and cluster 3—people well in-formed about the facts disclosed through the true statements but who were marginally unable to distinguish the false information. It was also found that education, sex and professional area are the most relevant sociodemographic factors associated with the level of information, and the highest motivations to consume EIs are their contribution to preserve the environment and natu-ral resources followed by being a more sustainable option (for 64.7% and 53.4% of participants, respectively). Hence it was concluded that, although some work still needs to be done to better inform people about EIs, there is already some conscientiousness that they constitute a good and more sustainable alternative to other types of meat.
- Analysis of factors influencing the physical, chemical and sensorial properties of Serra da Estrela cheesesPublication . Guiné, Raquel; Tenreiro, Marlene I. C.; Correia, Ana C.; Correia, Paula; Barracosa, PauloThe objective of this study was to evaluate the chemical, color, textural, and sensorial characteristics of Serra da Estrela cheese and also to identity the factors affecting these properties, namely thistle ecotype, place of production, dairy and maturation. The results demon- strated that the cheeses lost weight mostly during the first stage of maturation, which was negatively correlated with moisture content, being this also observed for fat and protein contents. During maturation the cheeses became darker and with a yellowish coloration. A strong corre- lation was found between ash and chlorides contents, being the last directly related to the added salt in the manufacturing process. The flesh firmness showed a strong positive correlation with the rind harness and the firmness of inner paste. Stickiness was strongly related with all the other textural properties being indicative of the creamy nature of the paste. Adhesiveness was posi- tively correlated with moisture content and negatively correlated with maturation time. The trained panelists liked the cheeses, giving high overall assessment scores, but these were not significantly correlated with the physicochemical properties. The salt differences between cheeses were not evident for the panelists, which was corroborated by the absence of correlation between the perception of saltiness and the analyzed chlorides con- tents. The Factorial Analysis of the chemical and physical properties evidenced that they could be explained by two factors, one associated to the texture and the color and the other associated with the chemical properties. Finally, there was a clear influence of the thistle ecotype, place of production and dairy factors in the analyzed properties.
- Analysis of factors that influence eating habits in different countriesPublication . Kalnina, I.; Straumite, E.; Klava, D.; Kruma, Z.; Bartkiene, E.; Isoldi, K.K.; Correia, Paula; Ferreira, Manuela; Guiné, Raquel P. F.Individual eating habits are influenced by a number of factors, including both internal variables such as physiology and emotion, as well as environmental factors such as food availability and cultural norms. Given the public health impact of dietary habits (choice, quality, amount, frequency) on health outcomes, it is important to understand what factors influence eating habits on a societal level. The aim of this research was to determine factors that influence eating habits and compare these factors between four different countries – Latvia, Lithuania, Portugal and the USA. An eating motivation questionnaire was used to measure eating habits in 3,348 respondents from different regions and countries. There were ten parts - demographical information, anthropometric data and behavioral and health related elements, sources of information about healthy eating, factors related to food choices according to motivations (health, emotional, economic, availability, social, cultural, environmental, political, marketing and commercials). Data were analyzed using descriptive statistics, and self-reported motivation was compared across countries. Health was the primary motivator of food selection in this sample (71% of respondents), whereas 34% reported that emotional factors impact their dietary habits and 35% reported that economic factors determine their food selection. A large number of respondents (44%) disagreed or strongly disagree or disagreed with the idea that marketing impacts their dietary habits. Portugal had the highest number of participants (86%), reporting that they agreed or strongly agreed with having health-related motivations for food selection, with Latvia (65%) and Lithuania (76%) showing more moderate levels of endorsement of healthy eating motivations, and the USA having the fewest respondents (52%) endorsing health-related motivations. Respondents from Portugal were more likely than respondents from the other countries to deny having emotional, economic and marketing motivations in food selection. From results can conclude that consumers are motivated by healthiness factors when making food choices (71% of respondents), but marketing, economic and emotional factors positively impact only 30% of consumers, other respondents completely disagreed or was indifferent to these types of motivations. Baltic countries (Latvia and Lithuania) were similar to each other, but Portugal and USA were completely different. Portugal strongly agreed with healthy motivations and disagreed with all other motivations, whereas USA and also Baltic countries had more equal division of opinions regarding impact of different motivations.
- Analysis of food buying behavior: A multinational study frameworkPublication . Guiné, Raquel P. F.; Ferreira, Manuela; Correia, Paula; Bartkiene, E.; Szucs, V.; Tarcea, M.; Ranilović, J.; Černelič-Bizjak, M.; Isoldi, K.; EL-Kenawy, A.; Ferreira, V.; Klava, D.; Korzeniowska, M.; Vittadini, E.; Leal, M.; Frez-Muñoz, L.; Papageorgiou, M.; Djekić, I.To make everyday food choices is a complex pro- cess, involving decisions which are influenced by distinct aspects associated with, among other fac- tors, purchasing ease, competitiveness of the mar- ket, advertising campaigns and marketing strategies, to mention a few related with aspects linked to com- mercialization. Hence, the objective of this study, which is integrated in the EATMOT project, was to as- sess some factors that influence food buying and food choice, in particular related with aspects such as price,convenience and marketing, as a function of some sociodemographic and geographic variables, namely, age, gender, marital status, level of education, living environment and country of residence. This study involved a questionnaire survey undertak- en on 11,960 participants from 16 countries. The in- strument used in this study was validated and trans- lated into the different languages of the participating countries, following double sided translation-checking methodology. The participants were from: Argentina, Brazil, Croatia, Egypt, Greece, Hungary, Italy, Latvia, Lithuania, Netherlands, Poland, Portugal, Romania, Serbia, Slovenia, and United States of America. The sample was selected by convenience and the partici- pation in the study was voluntary, being the question- naire applied only to adult citizens. Basic descriptive statistics were used for data analysis and the associ- ations between variables were investigated by cross- tabs and chi square tests. Additionally, a tree classifi- cation analysis was performed to assess the relative importance of each of the sociodemographic variables (gender, age group, level of education, country, living environment or marital status). The analysis followed the Classification and Regression Trees (CRT) algorithm with cross validation and the minimum number of cas- es considered for parent or child nodes was 100 and 50, respectively. For all data analysis, the software SPSS from IBM Inc. (version 25) was used and the level of sig- nificance considered was 5%. Results showed statistically significant differences (p < 0.0005) between groups for all sociodemographic vari- ables (gender, age, education, marital status, living en- vironment, country) in terms of the value attributed to convenience, price and marketing when buying foods. In most cases, the associations between the variables were considered very weak, although with a little high- er values for the associations between the country and variables “value convenience” (V = 0.179), “value price” (V = 0.158) and “value marketing” (V = 0.167). Tree clas- sification analysis confirmed for all three dependent variables that the most influential factor was country. This work highlighted that people in different coun - tries and from different sociodemographic groups show different motivations for buying food products.
- Analysis of Textural Properties of Gluten Free BreadsPublication . Correia, Paula; Guiné, Raquel P. F.; Fonseca, Mariana; Batista, L.Bread is one of the most important gluten-free foods, and it is usually connected with crumbling texture, poor colour, low volume, unsatisfactory taste and a short shelf-life, probably due to the lack of the viscosity network formed by gluten. Thus, some defects of gluten- free bread are related with inefficient gas retention and expansion during dough leavening, which results in a reduced volume and low crumb softness of the breads. The current challenge is for the industry to overcome these limitations. Furthermore, the texture is a characteristic that depends on the structure of the food, but also on the complex oral manipulation that aims to grind the food. In the present work the textural properties were analysed in breads made with special flours without gluten produced industrially, and the reproducibility of the results between breads from different batches was also evaluated. Two formulations of gluten-free flour were tested, provided by Germen (Portugal) (designated as A) and Credin (Denmark) (designated as B), and were also produced samples of bread with wheat flour type 65 (sample called Control), produced by CEREALIS (Portugal) - designated as A, B and Control samples, respectively. For analysis of the textural characteristics, a texturometer was used and perforation and compression tests were performed. The properties measured by the perforation test were: crust firmness, crumb firmness, adhesiveness, and stickiness. In the compression test, the characteristics evaluated were: hardness, elasticity, cohesiveness, resilience and chewiness. To evaluate the reproducibility, the breads were produced in four different batches, for each type of bread (A, B and Control), to assess whether the characteristics were maintained on the different days of manufacture. The results obtained for the perforation test showed that the loaves produced with gluten-free flours are less firm (in the crust and in the crumbs) and less adhesives when compared to bread made with type 65 flour (with gluten). Regarding stickiness, it can be said that there are not many apparent differences between the breads analysed, however bread B is more similar to Control bread. Bread A has a greater discrepancy between the top and the bottom in terms of stickiness, being more intense on the top of the bread. The compression tests showed that in the crumb the values are identical in all studied samples, including the control sample. However, when analysing the complete slice, it appears that samples A and B are considerably less hard than the Control, due to the crust contribution. The gluten-free breads presented lower resilience than the Control sample, with Sample B showing the highest concordance between the crumb and the complete slice. Moreover, the results showed both gluten-free breads had similar elasticity and chewiness values, both for the crumb and for the whole slices, and higher than the wheat bread. Regarding the reproducibility of the results, it was possible to observe that the perforation tests are preferable to those of compression, and that on the other hand the samples made with the flour without gluten type B are more uniform between batches. The results obtained in this study showed that the type of flour, its composition and the presence or absence of gluten significantly influence the texture of the breads produced. Breads made with gluten-free flours were less firm on the crust and crumbs when compared to wheat bread. On the other hand, gluten-free breads tend to be less sticky and slimy. Moreover, the two tests to evaluate the texture proved to be complementary, since they allow to evaluate different characteristics, and thus obtain a more complete profile of textural characteristics of the breads. The reproducibility of the results was higher for perforation tests compared to compression tests, and on the other hand the samples manufactured with type B gluten-free flour showed to be more constant in their texture characteristics, when different batches of bread were compared.
- Analysis of the air infiltration through the doorway of a refrigerated room using different approachesPublication . Gonçalves, J. C.; Costa, J.J.; Lopes, A.M.G.This paper presents the study of the air movement through the doorway of a refrigerated room, using both numerical and experimental approaches. Firstly, a comparison is made between the experimentally observed infiltration rates and the predictions by seven empirical models. For different test conditions of the specific laboratory configuration under analysis (a refrigerated room at laboratory scale), the infiltration rate was measured using the tracer gas technique. A three-dimensional numerical model was developed to simulate the heat and mass transfer phenomena, using a commercial CFD code (ANSYS-CFX®). For the simulations, turbulence effects were taken into account using the k- SST turbulence model. CFD results showed a good agreement with experimental data, confirming that the numerical model is appropriate to evaluate this physical phenomenon. The experimental and numerical results showed that the neutral flow level is located above the doorway mid-height and that the maximum airflow velocity occurs near the doorposts. Results also evidenced that, although most of the empirical models tend to overestimate the infiltration rate, some of them present a quite good prediction ability. Measurements in a real scale refrigerated room confirmed the trend obtained in the laboratory installation.
- Angular variation of fire rate of spreadPublication . André, Jorge C. S.; Goncalves, J. C.; Vaz, Gilberto C.; Viegas, Domingos X.Laboratory fire tests were performed in still air, for variable inclinations (10°, 15°) and fuel bed dimensions (1.28 × 2.50–3.0 × 4.6 m2), with homogeneous fuel beds of pine needles and pine wood excelsior. The fire ignition was made at a point, along a closed line with no fuel inside and along a straight edge of the fuel bed. The tests were recorded with an infrared camera and various techniques were developed to implement direct and indirect empirical methods of construction of the ‘orientation function’ of the fire in the given fuel bed and ambient conditions, showing how the rate of spread of a steady straight fire front depends on its orientation on the terrain. The direct method uses a set of straight fire fronts with various orientations whereas the indirect method uses essentially a point ignited fire front. Contrary to what is assumed in BehavePlus model, the orientation function is observed to depend significantly on the properties of the fuel bed. In all tests with closed fire fronts, the full steadiness required by the indirect method was not achieved (namely, at the head of the front), although, for slope angle of 10°, the corresponding errors induced on the orientation function were small.
- Angular variation of fire rate of spreadPublication . André, Jorge C. S.; Goncalves, J. C.; Vaz, Gilberto C.; Viegas, Domingos X.Laboratory fire tests were performed in still air, for variable inclinations (108, 158) and fuel bed dimensions (1.28 2.50–3.0 4.6m2), with homogeneous fuel beds of pine needles and pine wood excelsior. The fire ignition was made at a point, along a closed line with no fuel inside and along a straight edge of the fuel bed. The tests were recorded with an infrared camera and various techniques were developed to implement direct and indirect empirical methods of construction of the ‘orientation function’ of the fire in the given fuel bed and ambient conditions, showing how the rate of spread of a steady straight fire front depends on its orientation on the terrain. The direct method uses a set of straight fire fronts with various orientations whereas the indirect method uses essentially a point ignited fire front. Contrary to what is assumed in BehavePlus model, the orientation function is observed to depend significantly on the properties of the fuel bed. In all tests with closed fire fronts, the full steadiness required by the indirect method was not achieved (namely, at the head of the front), although, for slope angle of 108, the corresponding errors induced on the orientation function were small.
- Antimicrobial, Antioxidant, Sensory Properties, and Emotions Induced for the Consumers of Nutraceutical Beverages Developed from Technological Functionalised Food Industry By-ProductsPublication . Zokaityte, E.; Lele, V.; Starkute, V.; Zavistanaviciute, P.; Cernauskas, D.; Klupsaite, D.; Ruzauskas, M.; Alisauskaite, J.; Baltrusaitytė, A.; Dapsas, M.; Siriakovaite, K.; Trunce, S.; Guiné, Raquel; Viskelis, P.; Steibliene, V.; Bartkiene, E.This study aims to develop nutraceutical beverages containing food processing by-products in their formulation, and determine the opinion of consumers. This is done by testing whether they know that the main ingredients of the product are by-products, performing an overall acceptability test of the developed beverages, and evaluating the emotions induced by the newly developed beverages for consumers. The main ingredients used for the preparation of added-value beverages were fermented milk permeate (containing galactooligosaccharides), extruded and fermented wheat bran (WB) (containing ≥6.0 log 10 CFU g −1 viable antimicrobial properties showing lactic acid bacteria (LAB) strains), and different fruit/berry by-products (FBB) (as a source of compounds showing antioxidant properties). The definition of the quantities of bioactive ingredients was based on the overall acceptability of the prepared beverages, as well as on emotions induced in consumers by the tested beverages. Functional properties of the developed beverages were proofed by the evaluation of their antimicrobial and antioxidant properties, as well as viable LAB count during storage. Desirable changes in extruded and fermented WB were obtained: Fermentation reduced sugar concentration and pH in samples with predominant lactic acid isomer L(+). In addition, the viable LAB count in the substrate was higher than 6.0 log 10 CFU g −1 , and no enterobacteria remained. By comparing the overall acceptability of the beverages enriched with WB, the highest overall acceptability was shown for the samples prepared with 10 g of the extruded and fermented WB (7.9 points). FBB showed desirable antimicrobial activity: Shepherd inhibited—2, sea buckthorn—3, blueberries—5, and raspberries—7 pathogens from the 10 tested. Comparing different beverage groups prepared with different types of FBB, in most cases (except sea buckthorn), by increasing FBB content the beverages overall acceptability was increased, and the highest score (on average, 9.5 points) was obtained for the samples prepared with 5.0 and 7.5 g of blueberries FBB. Moreover, a very strong positive correlation (r = 0.8525) was found between overall acceptability and emotion “happy” induced in consumers by the prepared beverages enriched with extruded and fermented WB and FBB. By comparing the samples prepared with the addition of WB with samples prepared with WB and FBB, it was observed that most FBB increased total phenolic compounds (TPC) content (on average, by 9.0%), except in the case of samples prepared with sea buckthorn. A very high positive correlation (r = 0.9919) was established between TPC and antioxidant activity. Finally, it can be stated that the newly developed nutraceutical beverages were acceptable for consumers, induced positive emotions, and possessed desirable antimicrobial and antioxidant properties, while being prepared in a sustainable and environmentally friendly manner.