Percorrer por autor "Correia, Paula"
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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; 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 ( = 0.007) and water activity ( = 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.
- Consumption of nuts and similar dried foods in Portugal and level of knowledge about their chemical composition and health effectsPublication . Guiné, Raquel P.F.; Correia, Paula; Fernandes, Sara; Ramalhosa, ElsaNuts are consumed worldwide and have valuable nutritional compositions. However, few studies exist about the consumers‘ knowledge regarding nuts and similar dried fruits. This study aimed to investigate the knowledge on nuts composition (KNC) and health effects (KNHE) associated with nuts consumption and evaluate eating habits and preferences. A questionnaire survey was applied by direct interview to 300 Portuguese citizens, recruited by convenience. Anthropometric properties, behavioural and health aspects, knowledge about nuts composition and health effects, and consumption habits and preferences were evaluated and statistically analysed. Globally, the participants were not well informed on the chemical composition of nuts and about their effects on human health. Regarding age, the middle-aged adults showed a little higher level of KNC. However, no statistical differences were observed for KNC and KNHE across groups of Body Mass Index, physical exercise practice or balanced diet. Concerning eating habits and preferences, most participants (84%) like nuts, and usually consume them (58%). Among different nuts, the most consumed ones were peanuts and walnuts, followed by almonds and hazelnuts. A vast majority of participants (86%) preferred to eat the nuts in their simple form and consume them between meals. In conclusion, improvement of communication on nuts benefits to human health might be a way to increase their consumption. Our data can also help the nut industries to formulate a better strategy.
- Effect of different packaging materials on the shelf-life of chestnut (Castanea sativa Miller) during short-time storagePublication . Askri, Firas; Pereira, Ermelinda; Correia, Paula; Lema, Filipe; Martins, Fátima; Oueslati, Souheib; Droga, Rui; Ramalhosa, ElsaChestnuts are a perishable product that loses weight and spoils quickly. Therefore, it is essential to find methods to reduce economic losses. This study aimed to evaluate the effect of four different packaging materials - polyethene packaging" POLY", polyethene packaging with holes "PH", Modified Atmosphere Packaging "MAP", Vacuum bags "VAC-bags" and unpackaged chestnuts "control" - on the shelf-life of chestnuts stored at room temperature during 0, 2, 4 and 6 weeks. Several parameters such as colour, texture, moisture content, water activity, titratable acidity, total soluble solids, starch, amylose, aerobic mesophiles, and moulds and yeasts were determined. The results showed that the colour, texture, moisture content, water activity, titratable acidity and total soluble solids were little affected by the type of bags used. The starch ranged from 35.2 to 50.4% dry matter (d.m.) without a specific trend, and amylose expressed on the starch basis (25.7 to 45.0%) suggested no remarkable starch functionality changes. On the contrary, significant differences were observed between bags in weight loss, reducing sugars and microbial counts. The VAC-, MAP-, and POLY-bags showed percentages of weight loss lower than 2%, while the control and PH-bags had values equal to 13.2 and 9.2%, respectively. The highest values of reducing sugars were observed in POLY- and PH-bags, followed by the control, suggesting partial hydrolysis of the starch. Furthermore, VAC- and MAP-bags' application caused a considerable decrease in aerobic mesophiles, moulds and yeasts growth compared to the control during two and four weeks of storag
- Effect of different storage conditions on the stability and safety of almondsPublication . Rodrigues, Paula; Jelassi, Arij; Kanoun, Elifa; Sulyok, Michael; Correia, Paula; Ramalhosa, Elsa; Pereira, ErmelindaAlmond production in Portugal is of great importance for the economy of their main producing areas. However, the contamination of these nut fruits with fungi and mycotoxins poses a significant risk to food safety and security. This work intended to evaluate the influence of storage conditions on the microbial andmycotoxin stability and safety of almonds throughout long-term storage. Two almond varieties—Lauranne and Guara—were submitted to three different storage conditions, namely, 4◦C with noncontrolled relative humidity (RH), 60% RH at 25◦C, and 70% RH at 25◦C, for a storage period of 9 months. Samples were collected after 0, 3, 6, and 9 months of storage and analyzed for microbial loads (aerobicmesophiles, yeasts, and molds),mold incidence and diversity, and mycotoxin contamination. In total, 26 species were identified belonging to 6 genera: Aspergillus, Cladosporium, Fusarium, Penicillium, Paecilomyces, and Talaromyces. For the variety Guara, mycotoxins related to Aspergillus sect. Flavi, such as aflatoxins, averufin, versicolorin C, and norsolorinic acid, were detected only after 9 months of storage at 70% and 60% RH. Penicillium mycotoxins, such as quinolactacin A and roquefortine C, were also detected. For the variety Lauranne, Penicillium mycotoxins were detected, such as citrinin, quinolactacins A and B, roquefortines C and D, cyclopenin, cyclopenol, penitrem A, viridicatin, and viridicatol. Mycotoxins related to Aspergillus, such as aspulvinone E, flavoglaucin, paspalin, asperglaucide, asperphenamate, cyclo(L-Pro-L-Tyr), and cyclo(L-Pro-L-Val), were also detected.
- Effect of different storage conditions on the stability and safety of almondsPublication . Rodrigues, Paula; Jelassi, Arij; Kanoun, Elifa; Sulyok, Michael; Correia, Paula; Ramalhosa, Elsa; Pereira, ErmelindaAlmond production in Portugal is of great importance for the economy of their main producing areas. However, the contamination of these nut fruits with fungi and mycotoxins poses a significant risk to food safety and security. This work intended to evaluate the influence of storage conditions on the microbial and mycotoxin stability and safety of almonds throughout long-term storage. Two almond varieties-Lauranne and Guara-were submitted to three different storage conditions, namely, 4 degrees C with noncontrolled relative humidity (RH), 60% RH at 25 degrees C, and 70% RH at 25 degrees C, for a storage period of 9 months. Samples were collected after 0, 3, 6, and 9 months of storage and analyzed for microbial loads (aerobic mesophiles, yeasts, and molds), mold incidence and diversity, and mycotoxin contamination. In total, 26 species were identified belonging to 6 genera: Aspergillus, Cladosporium, Fusarium, Penicillium, Paecilomyces, and Talaromyces. For the variety Guara, mycotoxins related to Aspergillus sect. Flavi, such as aflatoxins, averufin, versicolorin C, and norsolorinic acid, were detected only after 9 months of storage at 70% and 60% RH. Penicillium mycotoxins, such as quinolactacin A and roquefortine C, were also detected. For the variety Lauranne, Penicillium mycotoxins were detected, such as citrinin, quinolactacins A and B, roquefortines C and D, cyclopenin, cyclopenol, penitrem A, viridicatin, and viridicatol. Mycotoxins related to Aspergillus, such as aspulvinone E, flavoglaucin, paspalin, asperglaucide, asperphenamate, cyclo(L-Pro-L-Tyr), and cyclo(L-Pro-L-Val), were also detected. Practical Application(Optional, for JFS Research Articles ONLY) The quality of almonds depends on the storage period and the RH and temperature at which they are stored. Storage of almonds at 60% RH at 25 degrees C is a good storage condition to maintain the stability and safety of nuts in terms of microbial and mycotoxin contaminations.
- Effect of moisture on the characteristics of hazelnut kernel during storagePublication . Correia, Paula; Filipe, Ana Filipa; Ferrão, Ana Cristina; Ramalhosa, Elsa; Guiné, Raquel P.F.The organoleptic and nutritional quality of hazelnuts during storage can be greatly influenced by environment conditions. The aim of this study was to evaluate the effect of moisture on the physicochemical characteristics of hazelnut kernels when stored under controlled conditions of temperature (25 °C) and different relative humidities (RH) (57.6, 68.9, and 78.6%). To obtain these RH in the hazelnut storage atmospheres, the salts NaBr, KI, and NH4Cl were used, respectively. The following properties were evaluated: moisture, water activity (aw), color, texture, and fat oxidative stability, both in the initial sample and after 1, 2, 4 and 6 months of storage. The results showed that there was a progressive increase over time in moisture and water activity, with growth being most pronounced from 4 months onwards. Moreover, hazelnuts stored at a RH of 78.6%, at 6 months of storage were completely spoiled, making their evaluation of impossible. The hardness and friability of the hazelnuts decreased over the storage time, with the differences being more pronounced for the samples subjected to higher RH. In general, the color of the skin and core of the fruits showed little variation over the storage time for all parameters evaluated (L*, a*, b*) and for all RH conditions tested. The hazelnuts stored at a RH of 78,6% could only be preserved until the 4th month, but presented low oxidative stability, being comparable to the hazelnuts with 6 months at RH of 57,6%, meaning that with a reduction of about 10% of RH it is possible to increase the oxidative stability about 2 months. Thus, it can be concluded that high relative humidities lead to a lower conservation of the quality characteristics of hazelnuts. Moreover, during the 6 months of storage the color of the fruits was little affected for the different RH tested, however all the other evaluated characteristics presented significant alterations, namely the texture and the oxidative stability of the fats.
- Effect of using microperforated bags on the storage of chestnut (Castanea sativa Mill) for six monthsPublication . Askri, Firas; Pereira, Ermelinda; Correia, Paula; Lema, Filipe; Martins, Fátima; Oueslati, Souheib; Droga, Rui; Ramalhosa, ElsaChestnuts are very consumed worldwide; however, it is a perishable product that loses weight and spoils quickly. So, it is crucial to find methods to reduce economic losses. Thus, the purpose of the present work was to study the effect of using microperforated bags (MP-bags) in long-storage of chestnuts in refrigerated industrial chambers for 1, 2, 3 and 6 months. The weight loss, colour, texture, water activity (aw), moisture content, titratable acidity (TA), total soluble solids (TSS), reducing sugars, starch, amylose, and microbiological analysis were determined. No significant differences were noted in the colour of the chestnut kernel between the MP-bags and the control (unpackaged chestnuts) in most situations. After six months, the weight loss was much lower in MP-bags (1.9%) than in control (23%), and a significant difference in moisture content was observed between both conditions (55.2 and 42.7%, respectively). After six months, TA and TSS varied between packages, while the starch did not. The packaging type and storage time significantly influenced the reducing sugars. The highest values were observed in control. Some variability, without a definite trend in the MP-bags, was observed along the storage period. In control, the contents of reducing sugars increased from 0.09 to 2.06 g glucose/100 g d.m.. No significant differences in aerobic mesophilic and moulds and yeasts were observed for the control and MP-bags at the end of storage. MP-bags demonstrated to be a promising solution for extending the shelf-life of chestnuts by preserving the nutritional quality of the fruits.
- Frutos secos de casca rija: valorização, enquadramento e perspetivasPublication . Ramalhosa, Elsa; Cabo, Paula; Correia, Paula; Ribeiro, CarlosDesde o ano 2000, a produção de frutos secos de casca rija (FSCR) tem demonstrado uma tendência crescente, tendo a produção nacional sido de 54 905 toneladas no ano de 2017. Trás-os-Montes destaca-se das restantes regiões agrárias, representando mais de 70% da superfície total plantada ou da produção nacional. Dada a importância deste subsector, em novembro de 2017 surge o Grupo Operacional ValNuts - Valorização dos frutos secos de casca rija (FSCR), onde os vários parceiros pretendem desenvolver soluções para minimização de perdas e manutenção da qualidade, levando a uma extensão do tempo de vida útil destes frutos, tanto em casca como em miolo. Deste modo, com base no estado da arte, na experimentação e no desenvolvimento tecnológico, é vantajoso melhorar a capacidade dos agentes desta fileira na preparação, manuseamento, acondicionamento e transporte de amêndoas (Prunus dulcis), avelãs (Corylus avellana) e noz (Juglans regia) produzidas em Portugal. Neste trabalho são apresentadas algumas condicionantes deste subsector de atividade económica e perspetivas de atuação para a persecução de metas objetivas.
- Influence of different parameters on the characteristics of hazelnut (var. Grada de Viseu) grown in PortugalPublication . Ferrão, Ana Cristina; Guiné, Raquel P.F.; Ramalhosa, Elsa; Lopes, Arminda; Rodrigues, Cláudia; Martins, Hugo; Correia, Paula“Grada de Viseu” is an indigenous hazelnut variety from Portugal, and it is considered by the producers as the most important variety in terms of production and productivity. Therefore, the aim of this study was to assess the influence of harvest year (2017/2018/2019) and location of production (Viseu/Faia) on some physical and chemical properties of the variety “Grada de Viseu,” namely biometric parameters, colour, true and bulk densities, texture parameters (hardness and friability), and chemical composition. The results showed that the fruits of the samples harvested in 2019 had higher values of height, width, and thickness. Hazelnuts from 2018 had a clearer shell, independently of the location of production, but only the samples from Faia harvested in 2018 had a clearer kernel. As for the texture, the fruits grown in Viseu harvested in 2018 had a harder shell and was more resistant to fracture, whereas the sample from 2019 had a harder kernel. In all cases, fat was the major chemical component. The sample from 2019 had a water activity greater than 0.62, meaning that its stability was not guaranteed. “Grada de Viseu” from Faia in 2018 presented a higher induction period and, therefore, was the one with the highest oxidation stability. The year of production showed to be the best predictor for almost every chemical and biometric characteristics. In general, it was possible to verify that harvesting year and geographical location influence hazelnut characteristics.
- Manual de boas práticas: amêndoa e avelãPublication . Ramalhosa, Elsa; Pereira, Ermelinda; Rodrigues, Paula; Fernandes, Luana; Pereira, J.A.; Bento, Albino; Ferrão, Ana Cristina; Quiné, Raquel; Correia, PaulaO presente Manual de Boas Práticas foi elaborado no âmbito do Projeto ValNuts (referência PDR2020-101-030755) com o intuito de valorizar a produção de frutos secos de casca rija em Portugal, potenciar a sua produção e obter frutos de excelente qualidade, aumentando o seu valor económico e a promoção da capacidade de exportação dos produtores. No presente Manual são discutidos alguns dados de produção, variedades mais plantadas nas regiões de Trás-os-Montes e Centro de Portugal, boas práticas a aplicar na colheita e no armazenamento da amêndoa e avelã, assim como as condições adequadas para o acondicionamento destes frutos e seus derivados para venda. Espera-se que com este Manual, os produtores sejam capazes de preservar durante um período de tempo maior a qualidade e segurança alimentar destes frutos. De facto, a aplicação de condições de secagem, transporte e armazenamento inadequadas podem-se traduzir em perdas de produção e económicas significativas, uma vez que ambas as culturas são de extrema importância nas regiões de Trás-os-Montes e Centro de Portugal.