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Gonçalves Oliveira Valente da Cruz-Lopes, Luísa Paula
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- Enhancing Liquefaction Efficiency: Exploring the Impact of Pre-Hydrolysis on Hazelnut Shell (Corylus avellana L.)Publication . Cruz-Lopes, Luísa; Duarte, Joana; Dulyanska, Yuliya; Guiné, Raquel; Esteves, BrunoHazelnut shells (HS), scientifically known as Corylus avellana L. shells, are waste produced by companies that process nuts. The main objective of this study was to find an efficient way to maximize the chemical potential of HS by solubilizing the hemicelluloses, which could then be used to recover sugars and, at the same time, increase the lignin content of this material to produce adhesives or high-strength foams. In order to optimize the pre-hydrolysis process, two different temperatures (160 and 170 °C) and times varying from 15 to 180 min were tested. All the remaining solid materials were then liquefied using polyalcohols with acid catalysis. The chemical composition of hazelnut shells was determined before and after the pre-hydrolysis. All of the process was monitored using Fourier Transform Infrared Spectroscopy with Attenuated Total Reflectance (FTIR-ATR) by determining the spectra of solids and liquids after the pre-hydrolysis and liquefaction steps. The highest solubilization of hazelnut shells was found for 170 °C and 180 min, resulting in a 25.8% solubilization. Chemical analysis after the hydrolysis process showed a gradual increase in the solubilization of hemicelluloses as both the temperature and time of the reactor were increased. Simultaneously, the percentages of α-cellulose and lignin in the material also increased with rises in temperature and duration. FTIR-ATR allowed for the detection of significant spectral changes in the hazelnut shells from their initial state to the solid residue and further into the liquefied phase. This confirmed that pre-hydrolysis was effective in enhancing the chemical composition of the material, making it more suitable for the production of adhesives, polyurethane foams, or in the production of bioplastics and composite materials, combined with other biopolymers or synthetic polymers to enhance the mechanical properties and biodegradability of the resulting materials.
- Edible Insects: Perceptions of Marketing, Economic, and Social Aspects among Citizens of Different CountriesPublication . Guiné, Raquel; Florença, Sofia De Guiné E; Costa, Cristina Amaro Da; Correia, Paula; Cruz-Lopes, Luísa; Esteves, Bruno; Ferreira, Manuela; Fragata, Anabela; Cardoso, Ana Paula; Campos, Sofia; Anjos, Ofélia; Bartkiene, Elena; Djekic, Ilija; Matran, Irina M.; Čulin, Jelena; Klava, Dace; Chuck-Hernández, Cristina; Korzeniowska, Malgorzata; Boustani, Nada M.; Papageorgiou, Maria; Gutiérrez, Bernardo Prieto; Černelič-Bizjak, Maša; Damarli, Emel; Ferreira, VanessaBecause edible insects (EI) have been, in recent years, recommended as a nutritious animal protein food with enormous environmental advantages over other sources of animal protein for human consumption, studies aimed at investigating the consumer perspective have become more prominent. Hence, this study intended to examine the perceptions of participants from different countries about the commercialization and economic and social impacts of edible insects. The study was made using a questionnaire survey, and data were collected in Brazil, Croatia, Greece, Latvia, Lebanon, Lithuania, Mexico, Poland, Portugal, Romania, Serbia, Slovenia, Spain, and Turkey. The final number of received answers was 7222 participants. For the treatment of the results, different statistical techniques were used: factor analysis, internal reliability by Cronbach’s alpha, cluster analysis, ANOVA to test differences between groups, and Chi-square tests. The results obtained confirmed the validity of the scale, constituted by 12 out of the 14 items initially considered, distributed by 4 factors: the first related to the economic impact of EIs, the second related to the motivation for consumption of EIs, the third related to the places of purchase of EIs, and the fourth corresponding to a question presented to the participants as a false statement. A cluster analysis allowed identifying three clusters, with significant differences between them according to all the sociodemographic variables tested. Also, it was found that the participants expressed an exceptionally high level of agreement with aspects such as the difficulty in finding EIs on sale, knowledge acting as a strong motivator for EI consumption, and the role of personalities and influencers in increasing the will to consume EIs. Finally, practically all sociodemographic variables were found to be significantly associated with perceptions (country, sex, education, living environment, and income), but not age. In conclusion, the perceptions about EI commercialization were investigated and revealed differences among samples originating from different countries. Moreover, the sociodemographic characteristics of the participants were found to be strongly associated with their perceptions.
- Effects of Pre- and Post-Harvest Factors on the Selected Elements Contents in Fruit JuicesPublication . Paula, Francisco; Guiné, Raquel; Cruz-Lopes, Luísa; Duarte, Armando; Fragata, Anabela; Reis, ManuelPre- and post-harvest factors determine the levels of the selected risk elements in100% fruit juices. The juices samples closely followed the Brix international reference values. Fruit juices presented the following order of the elements mean concentrations: cadmium (1.597 μg/l), chromium (2.767 μg/l), lead (20.75 μg/l), nickel (73.37 μg/l), zinc (545.9 μg/l), and iron (1792 μg/l), measured by AAS. The pre-harvest factors (origin, fruit, and agriculture) and the post-harvest factors (blending, packaging, conservation, pasteurisation, and process) were evaluated according to the manufacturers information and were correlated with the elements concentrations of fruit juices. A strong relationship was detected between the fruit species used for the juice production (i.e. pre-harvest factor) and their elements concentrations. Furthermore, multiple correspondence analysis was used for reducing the data dimension by grouping the factors. The zinc concentration was detected as a potential proxy for the identification of the fruit juices manufacturing process.
- Nanotechnology in Food: Technlology, Applications and SafetyPublication . Cruz-Lopes, Luísa; Macena, M.; Guiné, RaquelNanotechnology has brought immense possibilities to the food and agricultural sectors. However, it has also been perceived as posing many issues, particularly regarding the safety of humans, ecosystems and all living organisms involved. Therefore, it is very important to discuss the possible applications of nanotechnology in the food industry or even in a broader scale in the whole food supply chain, as well as extend these applications ensuring the safety of all those involved. Additionally, it is vital to look at the perspective of the general public and try to understand if it are aware of the possible application of nanotechnology to the food they consume, or to the packaging materials that are in contact with foods as well as if it knows the risks associated to this technology. Finally, it is also important to investigate if the real risks are negligible from the technical and scientific points of view, but if the consumer perceives them on a much larger scale owing to lack of correct information available. This chapter aims to depict some applications of nanotechnology in the food supply chain and the corresponding risks involved as well as how the consumer perceives them.
- Edible Insects: Consumption, Perceptions, Culture and Tradition Among Adult Citizens from 14 CountriesPublication . Guiné, Raquel; Florença, Sofia De Guiné E; Costa, Cristina Amaro Da; Correia, Paula; Cruz-Lopes, Luísa; Esteves, Bruno; Ferreira, Manuela; Fragata, Anabela; Cardoso, Ana Paula; Campos, Sofia; Anjos, Ofélia; Boustani, Nada M.; Bartkiene, Elena; Chuck-Hernández, Cristina; Djekic, Ilija; Tarcea, Monica; Sarić, Marijana Matek; Kruma, Zanda; Korzeniowska, Malgorzata; Papageorgiou, Maria; Árias, Leticia González; Černelič-Bizjak, Maša; Damarli, Emel; Ferreira, Vanessa; Bayraktaroğlu, Emre; Arpa, Fatmanur OzyurekAlthough edible insects (EIs) are encouraged as a sustainable source of protein, their consumption is not as generalised as other types of food that are internationally accepted. While in some regions of the world, EIs are part of the gastronomic and cultural traditions, in other regions, people are not so receptive to this type of food, and some people even express some disgust towards it. Hence, this research focused on the habits of the participants regarding the consumption of insects as well as their perceptions about EIs being or not a part of the local culture or gastronomic patrimony. A questionnaire survey was implemented in fourteen countries (Brazil, Croatia, Greece, Latvia, Lebanon, Lithuania, Mexico, Poland, Portugal, Romania, Serbia, Slovenia, Spain, and Turkey), and globally, 7222 adult participants responded to the questionnaire. SPSS software (version 28) was used to process the data and carry out chi-square tests and Factor Analyses (FA). The obtained results showed significant differences between countries for all the questions included in the survey, either those regarding the habits of the participants or their opinions about the facts linked with EI tradition or cultural aspects. It was found that participants from Mexico consume EIs more than in all other countries and that strong motivations that would lead to consumption among those who do not consume include curiosity and food shortage. The solution obtained with FA considering the ten statements of the scale consisted of two factors: F1—Culture and Tradition of EIs (α = 0.675) and F2—Acceptance of EIs (α = 0.614). In conclusion, the consumption of EIs and the perceptions of people are highly variable according to geographic location and cultural environment.
- Consumer perspective about plastic food packagingPublication . Macena, Morgana; Cruz-Lopes, Luísa; Guiné, RaquelPlastic materials have been increasingly used for food in the latest decades, due to the many advantages associated with these materials: they offer considerable design flexibility; they are cheap and lightweight; and they have a wide range of physical and optical properties important to preserve the foods. Plastics made from petroleum are not degradable and are discarded in the environment, originating huge environmental problems, threatening all forms of life by entering the food chains. This work focused on the perspectives of Portuguese consumers concerning plastic food packaging and its consequences for the environment and the ecosystems. The research included a questionnaire survey applied to a sample of 385 adult citizens. The results showed that the participants are inclined to reflect about the negative impact of plastic packaging on the ecosystems and about 40% admit that they sometimes do not buy plastic while 30% try to use alternative materials. An important percentage, over 80%, are in favour of prohibition to use plastic utensils of single usage and the limitation in the use of plastic bags to carry goods and foods in particular. Most participants revealed a good knowledge about recycling and are favourable to the use of recycled materials. Nearly 90% of the participants separate the different types of waste aimed at recycling. Although shifting the usage of plastic towards more sustainable options has been facing some difficulties, it is also verified that consumers are becoming more worried about the impact of their choices on the sustainability of ecosystems and the whole planet Earth.
- Particleboard Production from Paulownia tomentosa (Thunb.) Steud. Grown in Portugal.Publication . Esteves, Bruno; Aires, Pedro; Sen, U; Gomes, Maria da Glória; Guiné, Raquel; Domingos, Idalina; Ferreira, José; Viana, Helder Filipe dos Santos; Lopes, Luísa P. Cruz
- Liquefaction optimization of Crataegus monogyna JacqPublication . Dulyanska, Y; Cruz-Lopes, Luísa; Esteves, Bruno; Domingos, Idalina; Ferreira, José; Guiné, Raquel; Gonçalves, Fernando Jorge; Carvalho, L B; Barroca, M JThe objective of this work was to evaluate the potentiality of Crataegus monogyna Jacq. residues to be liquefied by polyhydric alcohols and the chemical transformations observed in this process with subsequent use to produce polyurethane foams. The variations on liquefaction yield were determined at different temperature, time, material/solvent ratio and granulometry. Results show that liquefaction performed at 180 °C with a 1:10 material/solvent ratio increases along time, reaching a maximum at 60 min. Similarly, liquefactions made during 60 min with a 1:10 material/solvent ratio show that there is an increase in liquefaction yield with the increase in temperature until 180 °C. A higher temperature could increase the liquefaction yield but would lead to a higher energy consumption in the process. There seems to be no significative advantage in increasing material/solvent ratio above 1:7, although the liquefaction yield increases for higher ratios. Granulometry testing shows that the smaller the particle the best is the liquefaction percentage. It was concluded that the best liquefaction yield, of approximately 81%, was obtained with a temperature of 180 °C, for 60 min and particle size <80 mesh for Crataegus monogyna Jacq. This material has good properties to be converted in a liquid mixture that can be used later, on the production of polyurethane foams.
- Perceções sobre a produção e comercialização de insetos comestíveis e seu papel no desenvolvimento em comunidades ruraisPublication . Guiné, Raquel; Florença, Sofia De Guiné E; Costa, Cristina Amaro Da; Correia, Paula; Lopes, Luísa P. Cruz; Esteves, BrunoOs insetos comestíveis (IC) têm vindo a ser promovidos a nível global como uma forma de diversificar a ingestão de alimentos ricos em proteína de origem animal, devido às suas vantagens em termos de sustentabilidade e impacto ambiental. Porém, a sua criação e comercialização, pode também ser vista como uma forma de promover a sustentabilidade económica de famílias e comunidades rurais. Assim, este trabalho teve por objetivo focar-se nos aspetos económicos e socais associados aos IC. Para tal foi realizada uma investigação por questionário, a participantes residentes em Portugal, através de resposta on-line, numa amostra constituída por 527 participantes. Os resultados mostraram que os participantes reconhecem que os IC podem contribuir para aumentar o rendimento de famílias mais vulneráveis, que em alguns países a criação de insetos está a tornar-se um fator chave na luta contra a pobreza rural, mas também que o rendimento gerado pelos insetos pode ser afetado pelas flutuações de preço do mercado e disponibilidade. Por outro lado, a maioria dos Portugueses desconhece que já podem ser encontrados à venda em supermercados nacionais produtos contendo insetos comestíveis. Em conclusão, este trabalho mostrou algumas perceções e tendências que podem ser úteis para levar criadores Portugueses a investir nesta área.