Pastas enriched in Fucus vesiculosus: nutritional evaluation and biological properties

• Autor(a) principal: Afonso, Nuno Filipe Costa
• Data de Publicação: 2019
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10773/30034
• topic: Phaeophyta; Fucus vesiculosus; Fortified pasta; Nutritional composition; Phytochemicals; Antioxidant activity; Bioaccessibility; Bioavailability

Despite their worldwide abundancy, algae are still considered an underexploited resource with a lot of interest in several industries, namely food and pharmaceuticals. Several reports comparing the diets of different countries, associate seaweed consumption with the oriental welfare and vitality contrarily to western societies. Within all three classes of edible seaweeds, those belonging to Phaeophyta have been receiving a lot of attention particularly due to their abundance in complex polysaccharides, phlorotannins, fucoxanthin and iodine. This work reports the nutritional composition (total fibre content, protein, ash and minerals) and phytochemical content (pigments and phlorotannins) of a pasta fortified with 1% and 5.5% of brown seaweed Fucus vesiculosus, prior and after the cooking process. In parallel the biological activities were evaluated namely antioxidant potential and capacity of inhibiting three metabolic enzymes, α-amylase, α-glucosidase and pancreatic lipase. Lastly, mineral bioaccessibility and bioavailability was accessed. Overall, the gathered results demonstrate that with each increasing seaweed concentration there is a tendency of improving several parameters. On a first approach, both fibres and ash contents increased up to 48% and 60%, respectively, while protein content remained unchanged. Further confirming the higher levels of ash on enriched samples, iodine content was augmented to around 91% of its initial concentration. Furthermore, F. vesiculosus contributed to a phytochemical increase, namely pigments, such as chlorophyll a (84%) and carotenoids (99%), and phlorotannins (87%) on the target pastas. Altogether, these results are most likely related to the improvement of the antioxidant capacity of the samples. Upon cooking, a general decrease on several contents was noted, namely protein, mineral and phytochemicals, which reflected a decline of the antioxidant property. The maintenance of fibre content upon this thermal processing possibly prompted to numerous effects, such as the retention of protein, to an extent, proving itself advantageous, but also the retention of minerals when submitted to simulated gastrointestinal digestion. Amongst all studied minerals, K and Mg fractions presented the highest percentages, 105% and 62% for the bioaccessible ones, and 56% and 24% for the bioavailable ones, respectively. Additionally, iodine stood out with a bioaccessible fraction of 82%. This element also had a bioavailability of 4%; however, it is estimated that the consumption of 100g of pasta could provide approximately 54% of its recommended daily dose. So, despite the positive developments and the good insight on the impact of both the seaweed incorporation and the cooking process, a lot of research is still required to optimize this product and to address the viability beyond in vitro assays.