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- Chemical and Physical Properties of Some Hazelnut Varieties Grown in PortugalPublication . Ferrão, Ana Cristina; Guiné, Raquel P. F.; Ramalhosa, Elsa; Lopes, Arminda; Rodrigues, Cláudia Filipa; Martins, Hugo; Gonçalves, Roberto; Correia, PaulaHazelnuts are one of the most appreciated nuts worldwide due to their unique organoleptic and nutritional characteristics. The present work intended to analyse several physical and chemical properties of different hazelnut varieties grown in Portugal, namely Tonda de Giffoni, Grada de Viseu, Segorbe, Longa de Espanha, Butler, Gunslebert, and Negreta. In general, the results revealed statistically significant differences between the varieties under study. The Gunslebert had more elongated hazelnuts and with heavier shelled fruits, while the kernels of the Grada de Viseu revealed to be heavier. Grada de Viseu was harder in the shell, Gunslebert had a harder core, and Segorbe was more resistant to fracture. Fat was the more representative component for all varieties and in some cases the values of moisture and water activity were over the recommended amount (≥0.62). Tonda de Giffoni was the variety with the highest induction time, indicating the highest oxidation stability. Moreover, discriminant analysis revealed that the variables more important to distinguish the varieties were protein (λ = 0.007) and water activity (λ = 0.010). The results of this study help to better understand the differences between some hazelnut varieties that are cultivated in Portugal, which gives important hints for all players in the hazelnut sector.
- Flores comestíveis como fonte de compostos bioativos com atividade antioxidantePublication . Guiné, Raquel P. F.; Ferrão, Ana Cristina; Correia, Paula; Goncalves, J. C.; Gonçalves, Fernando JorgeExistem muitas espécies vegetais utilizadas na gastronomia, entre as quais as flores comestíveis (FC). Para que uma flor seja considerada comestível ela deve ser não tóxica, inócua e ter propriedades nutricionais. Historicamente, as FC têm sido usadas para fins culinários há séculos em várias partes do mundo, como Ásia, Grécia antiga, Roma e também na França medieval. Adicionalmente, constituem uma boa fonte de compostos bioativos, nomeadamente fitoquímicos, associados a várias propriedades farmacológicas, destacando a proteção contra doenças cardiovasculares e os efeitos ansiolíticos, anticancerígenos, antidiabéticos, anti-inflamatórios, antioxidantes, diuréticos, imunomoduladores e antimicrobianos. Recentemente, as FC têm despertado crescente interesse, devido às suas propriedades estéticas e organoléticas, bem como potenciais benefícios para a saúde, relacionados com a ocorrência de alguns compostos bioativos. Nesta medida, o objetivo do presente trabalho foi avaliar os teores de compostos fenólicos totais, antocianinas e flavonoides, bem como a atividade antioxidante num conjunto de FC. Para a análise foram obtidos extratos de onze espécies de FC que foram utilizados para a quantificação da composição fenólica e atividade antioxidante usando métodos espectrofotométricos. Dos resultados obtidos foi possível verificar que as rosas e cravos de coloração vermelha ou rosa se destacaram como contendo maiores teores de compostos fenólicos totais (18 a 27 mg EGA/g), e ainda maiores aportes de antocianinas (3 a 5 mg EC/g). Verificou-se ainda que eram também essas as FC com maior atividade antioxidante (12 a 16 mg ET/g). De destacar por fim o cravo vermelho como contendo maior quantidade de flavonoides (cerca de 18 mg EC/g). Em conclusão, verifica-se que as FC, para além das suas potencialidades gastronómicas, podem constituir um veículo para a ingestão de compostos com efeitos benéficos para a saúde, nomeadamente no que respeita ao combate aos radicais lives responsáveis pelo envelhecimento celular.
- Influence of emotional determinants on the portuguese food choicesPublication . Guiné, Raquel; Ferrão, Ana Cristina; Correia, Paula; Cardoso, Ana Paula; Ferreira, Manuela; Duarte, JoãoFood choices are a complex system influenced by many factors, such as for example, environmental, political, physiological and emotional. It is well established in the literature that, not only, emotions influence what people choose to eat, but also people’s food choices influence their emotions. Emotional eating is defined as the tendency to eat more in response to negative emotions and can lead to several health problems, namely obesity and eating disorders. Since this is an emergent problem in today’s society, the main goal of this study was to analyse the influence that emotional determinants had on people‘s food choices and also investigate in what extension the particular characteristics of an individual affect the influence that emotional determinants had on people’s food choices. For that purpose, it was created a questionnaire and undertaken a descriptive cross-sectional study on a non-probabilistic sample of 1314 Portuguese participants. To measure the influence that emotional determinants had on the participant’s food choices it was used a scale ranging from -2 to +2, which can be interpreted as follows: [-2.0; -1.5[ - food choices not at all influenced by emotional determinants; [-1.5; -0.5[ - food choices not influenced by emotional determinants; [-0.5; 0.5[ - food choices slightly influenced by emotional determinants; [0.5; 1.5[ - food choices influenced by emotional determinants; [1.5; 2.0] - food choices strongly influenced by emotional determinants. The results revealed that the participants’ food choices were, in general, slightly influenced by emotional determinants (mean scores between -0.5 and 0.5, on scale from -2 to +2). Furthermore, were found significant differences between the groups of all the variables under study (age group, gender, level of education, professional status, area of work or studies, BMI class and the fact that the participants had already experienced an episode of any eating disorder). The participants who already experienced a binge-eating episode were the ones that obtained the highest mean score (0.63 ± 0.79), meaning that in this case, the food choices of those participants were influenced by emotional determinants. Therefore, this study suggests that emotional determinants are influenced by the characteristics of each individual and also that there seems to be a positive association between emotional eating and the existence of eating disorders, especially, binge-eating. Hence, these findings are important to develop and implement strategies that can increase healthier eating habits.
- Analysis of drying kinetics of eggplant through thin layer models and evaluation of texture and colour propertiesPublication . Ferrão, Ana Cristina; Guiné, Raquel; Correia, Telma; Rodrigues, RosaEggplant is a food with unique characteristics. However, due to its high moisture content it is very perishable. Thus, to increase its shelf life it can be applied the drying process. This work aimed at studying the effects of drying on eggplant, namely on the physical properties of colour and texture, as well as the analysis of drying kinetics by thin layer models. The drying was carried out using a convection chamber with a temperature of 80ºC and an air velocity of 0.5 m/s. The texture profile analysis was done with a texturometer equipped with a 75 mm probe and the colour measurement was performed with a calorimeter in the CIELab coordinates. For both texture and colour, all analysis were done in triplicate, before and after drying. The results showed that there were clear differences in colour, with the difference being higher in the case of the dried sample (E = 25.95) when compared to the fresh sample analysed 10 minutes after the cut (E = 9.69).Regarding the texture, drying caused alterations in the eggplant structure, with an increase in elasticity and chewiness and a decrease in hardness, resilience and cohesiveness. As for the kinetics, the sample took 2.5 hours to reach a moisture content of approximately 10%. Four thin layer models were tested, being the Wang & Singh model the one that proved to be the most suitable to fit the experimental data, with a correlation coefficient equal to 0.9902.
- Study of consumer acceptance about the possible commercialization of a cheese with berriesPublication . Ferrão, Ana Cristina; Guiné, Raquel; Correia, PaulaBACKGROUND: Nowadays, consumers are more concerned about the issues related to the maintenance and promotion of health, trying to combine the pleasure in the consumption of certain foods with health benefits. Therefore, there has been an increasing in the market of functional foods. OBJECTIVE: The present study was carried out in order to explore the consumers’ acceptance regarding the possibility of introducing in the market a new dairy product with functional properties, namely a cheese with berries. METHODS: A descriptive cross-sectional study was undertaken on a non-probabilistic sample of 335 adult participants. The questionnaires were applied online after informed consent only to adults (aged 18 or over) and the data were collected from August 2016 to March 2017 among the Portuguese population. RESULTS: The results obtained showed that approximately 92% of the participants consumed cheese of any type regularly and 50% consumed cheese two or three times per week. Most of the participants (~62%) revealed that they did not consume any type of cheese with additional benefits. Nevertheless, they indicated that they might be potential consumers of a cheese with berries (~73%) and would like the product to have the ability to improve cardiovascular health (~73%) and have high antioxidant capacity (~51%). Participants recognized as very important the addition of ingredients such as blackberry, raspberry, gooseberry, blueberry, strawberry or cherry, and manifested that all of the ingredients suggested might combine well with cheese. CONCLUSION: This work showed that the introduction in the market of this new dairy product, a cheese with berries, might be a successful strategy.
- Consumer perception about edible insects’ relation with environment and sustainabilityPublication . Guiné, Raquel P. F.; Florença, Sofia De Guiné E; Ferrão, Ana CristinaEdible insects have been suggested as a potential environmental and economic solution to replace less sustainable conventional protein sources for human nutrition. Hence, this work investigated the perceptions and knowledge of consumers in fourteen different countries towards edible insects and their relation with environment and sustainability. For that, data were collected through a questionnaire survey in the ambit of the EISuFood Project, and 7221 responses were obtained. The results showed that although participants had some difficulty in identifying wrong statements, a majority were able to express disagreement towards them (ex. comparison between poultry and insect productions for water requirements, comparison between pork and insect productions for area requirements). A great majority of respondents showed agreement with true statements, like insect production emits fewer greenhouse gases than beef production. Higher percentages of respondents that did not manifest a decisive opinion were found for insects being able to efficiently convert organic matter into protein, or for loss of biodiversity being lower for insect compared to other animal productions. Sociodemographic variables sex and education were significantly influenced knowledge on most of the questions, while age was not found so influential. Regarding the geographic variable living environment, it significantly influenced the knowledge on practically all items, and country significantly influenced knowledge in all of the questions, being the most influential of all variables studied. As a conclusion, it was fund that perception about edible insects and sustainability are influenced by sociodemographic characteristics of the participants and greatly variable according to geographical factors.
- Investigation about the consumption of edible flowers in PortugalPublication . Guiné, Raquel; Florença, Sofia G.; Ferrão, Ana Cristina; Correia, PaulaNowadays the interest in the use of edible flowers for gastronomy purposes has increased. Therefore, the aim of this study was to evaluate the extent to which socio demographic characteristics influenced the knowledge and consuming habits related to edible flowers in a sample of 247 Portuguese adults. The results revealed that this subject is not unknown for the majority of the participants and that they were aware of some of aspects related to the consumption of this kind of product. In general, edible flowers are consumed sporadically, cooked or incorporated in salads and mainly because of their taste. It was also observed that gender as well as the area of work or studies influenced the participants’ knowledge and some of the consuming habits related to edible flowers. However, there were still some aspects about which the participants revealed some confusion, such as for the example the risks related to their consumption. Hence, it is important to continue with studies in this area, in order to clarify and deepen the knowledge about the use of edible flowers in gastronomy.
- Evaluation of phenolic and antioxidant properties of strawberry as a function of extraction conditionsPublication . Guiné, Raquel; Correia, Paula; Ferrão, Ana Cristina; Gonçalves, Fernando; Lerat, Clémence; El-Idrissi, T; Rodrigo, EWe studied the extraction of antioxidant phenolic compounds, anthocyanins and the evaluation of antioxidant activity of strawberries in different extraction conditions, varying the type of solvent (ethanol:water (50%) and acetone:water (60%), the extraction time (15 and 60 min) and the solvent volume to sample mass ratio (5 mL/g and 20 mL/g). In addition, we performed principal component analysis and cluster analysis. The results showed that, although the two solvents tested had similar influence on total phenolic compounds extraction and antioxidant activity, the 60 minutes of extraction and the use of the solvent volume/sample mass ratio of 20 mL/g were the best extraction conditions, both for the 1 st and 2 nd recovered extracts. However, the solvent had a marked effect on anthocyanins’ extraction, so that acetone/water extracted almost the double as compared to ethanol/water, for the same extraction conditions. Finally, factor analysis allowed identifying a grouping structure of two components, which was confirmed by the dendogram obtained from cluster analysis.
- The motivations that define eating patterns in some Mediterranean countriesPublication . Guiné, Raquel; Ferrão, Ana Cristina; Ferreira, Manuela; Correia, Paula; Cardoso, Ana Paula; Duarte, João; Rumbak, Ivana; Shehata, Abdel-Moneim; Vittadini, Elena; Papageorgiou, MariaPurpose: This study is part of the international project EATMOT, designed to investigate several issues related to food choice and consumption patterns in different countries, including health related factors; economic and availability aspects; emotional determinants; social, cultural and religious influences; marketing and advertising campaigns and finally environmental concerns. Methodology: The present study was based on a questionnaire that was exclusively prepared for the project, and which was applied to collect data in different countries, in particular Croatia, Egypt, Italy, Greece and Portugal, which are typically associated with the Mediterranean diet. Findings: The results obtained allowed, in general, to conclude that in all 5 countries the motivations related to health as well as environment & politics were the more relevant to determine people’s eating habits (scores varying from 0.3 to 0.7). Women were more influenced by eating motivations than men, and people with moderate exercise were more susceptible to health and environmental motivations and less to emotional, social or marketing motivations (p <0.001 in all cases). It was also observed that people who adopted a special diet were more prone to eating motivations and that the emotional motivations were more pronounced in people with eating disorders (p <0.001). Finally, people without chronic diseases or allergies were even more influenced by health motivations than those who actually suffered from these health problems (p <0.001 in both cases). Originality/Value: This work is important due to the multinational coverage, thus allowing to evaluate the most relevant factors that influenced the food choices of the populations around the Mediterranean Sea, sharing the common link to the Mediterranean Diet. The study allowed concluding that, in general, the food choices were primarily determined by health factors, and also by concerns related to the environment and sustainability as well as by political influences.
- Study about eating habits of higher education studentsPublication . Florença, Sofia G.; Ferrão, Ana Cristina; Ferreira, Manuela; Duarte, João; Nunes, B.; Morais, P.; Sanches, R.; Abrantes, D.; Guiné, RaquelIntroduction: The transition from secondary school to university is associated with many changes, at the social and surrounding influences’ levels, which may be a risk factor for unhealthy lifestyles. It is known that the years spent at the university may be associated with poor eating habits, with levels of fast-food consumption higher than desirable, possibly low intake of fruits and vegetables and breakfast skipping, among others. Objective: This study investigated some eating habits in a sample of students frequenting higher education establishments in the Centre of Portugal. Methods: It was carried out a questionnaire survey of self-response to investigate some of the eating habits of the participants. The questionnaire was applied after all ethical issues were guaranteed and after approval by the ethical committee. The number of valid questionnaires obtained was 670. Results: In the sample evaluated, most of the students revealed satisfactory eating habits, with significant differences between age groups, the area of studies and the practice of high competition sport. A considerable percentage of the participants, 40.8%, ate 5 meals per day and only 0.6% ate less than 3 meals per day. Only 6.6% of the participants indicated that usually do not eat breakfast. In general, the participants’ breakfast included milk (54.0% of positive answers), bread (45.8% of positive answers), cereals (32.7% of positive answers) and coffee (23.9% of positive answers). Regarding lunch, 30.1% of the participants ate soup, 28.4% consumed vegetables, 28.2% ate pasta, 21.6% fish, 16.0% potatoes, 2.5% yoghurt, 15.5% soft juices, 4.3% juices, 23.6% salad, 10.4% chips, 58.2% meat, 38.5% rice, 27.8% fruit, 9.4% a sweet desert and 44.9% drank water. Conclusions: The results pointed to the necessity of improving educational programs which can contribute to improve university students’ eating habits.