Escola Superior de Turismo e Tecnologia do Mar
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Browsing Escola Superior de Turismo e Tecnologia do Mar by Field of Science and Technology (FOS) "Ciências Agrárias::Biotecnologia Agrária e Alimentar"
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- Evaluating the Potential of the Defatted By-Product of Aurantiochytrium sp. Industrial Cultivation as a Functional FoodPublication . Reboleira, João; Félix, Rafael; Félix, Carina; Melo, Marcelo M. R. de; Silva, Carlos M.; Saraiva, Jorge A.; Bandarra, Narcisa M.; Teixeira, Bárbara; Mendes, Rogério; Paulo, Maria C.; Coutinho, Joana; Lemos, Marco F. L.While Aurantiochytrium sp. is an increasingly popular source of polyunsaturated fatty acids (PUFAs), its extraction generates high amounts of waste, including the spent, defatted residue. The composition and bioactivities of this by-product could prove to be a major part of the sustainable valorisation of this organism within the framework of a circular economy. In this study, the defatted biomass of commercial Aurantiochytrium sp. was nutritionally characterised, and its amino acid profile was detailed. Additionally, the antioxidant and prebiotic potentials of an enzymatically digested sample of defatted Aurantiochytrium sp. were evaluated under a set of miniaturised in vitro assays. The nutritional profile of the spent Aurantiochytrium biomass revealed a protein and dietary-fibre rich product, with values reaching 26.7% and 31.0% for each, respectively. It also held high concentrations of glutamic and aspartic acid, as well as a favourable lysine/arginine ratio of 3.73. The digested samples demonstrated significant Weissela cibaria and Bifidobacterium bifidum growth-enhancing potential. Residual ferric reducing antioxidant power (FRAP) activity was likely attributed to antioxidant amino acids or peptides. The study demonstrated that some of the nutritional and functional potential that reside in the defatted Aurantiochytrium sp. waste encourages additional studies and the development of food supplements employing this resource’s by-products under a biorefinery framework.
- Production of parsley and pennyroyal with an African catfish-based aquaponics partially fed with yellow mealworms - Tenebrio molitorPublication . Bernardino, Raul; Vieira, Judite; Vaz, Daniela C.; Santos, Ounísia D.; Ribeiro, Vânia S.; Pires, Cristiana L.; Cotrim, Luís; Bernardino, SusanaInsects can be used as alternative protein/food sources. Here, a novel aquaponic system based on the African catfish (Clarias gariepinus) fed with 30% of yellow mealworms (YM) (Tenebrio molitor) as substitute feed to 100% of fish meal (FM) was employed to produce parsley (Petroselinum crispum) and pennyroyal (Mentha pulegium). The two systems implemented (30YW/70FM and 100FM - control) showed identical water quality parameters. The 30YW/70FM operation led to a reduction by 27% of the carbon footprint, relatively to the 100FM system. Plants cultivated in the 30YW/70FM aquaponic system led to lower plant biomass (↓∼75%), as stated by the statistically significant (p < 0.05) lower values of “plant height”, “foliage diameter”, “leaf number”, “biggest leaf length” and “root length”. Moreover, 100FM parsley showed higher levels of greenness (100%) and health status (97%) than the 30YW/70FM plants (↓50% greenness; ↓20% health status). Likewise, 100FM pennyroyal also showed higher levels of greenness (100%) and health status (100%) than 30YW/70FM pennyroyal (↓56 % greenness; ↓59% health status). Also, even if all plants presented equivalent levels of P, K, Ca and Fe, the plants grown in the 30YW/70FM system showed some Cl-accumulation (>7.0 g Cl.kg−1 for parsley and > 4.0 g Cl.kg−1 for pennyroyal, in dry weight) in the leaves and Cu and Mn accumulation in the roots (> 0.4 g.kg−1 in dry weight). The presence of high concentrations of Cl in T. molitor, and consequently in the water and fish faeces, might have caused some abiotic stress and toxicity to plant tissues, reducing plant growth.
- Protein oxidation in emulsified cooked burger patties with added fruit extracts: Influence on colour and texture deterioration during chill storagePublication . Ganhão, Rui; Morcuende, David; Estévez, MarioThe influence of protein oxidation, as measured by the dinitrophenylhydrazine (DNPH) method, on colour and texture changes during chill storage (2. °C, 12. days) of cooked burger patties was studied. Extracts from arbutus-berries (Arbutus unedo L., AU), common hawthorns (Crataegus monogyna L., CM), dog roses (Rosa canina L., RC) and elm-leaf blackberries (Rubus ulmifolius Schott., RU) were prepared, added to burger patties (3% of total weight) and evaluated as inhibitors of protein oxidation and colour and texture changes. Negative (no added extract, C) and positive control (added quercetin; 230. mg/kg, Q) groups were also considered. The significant increase of protein carbonyls during chill storage of control burger patties reflect the intense oxidative degradation of the muscle proteins. Concomitantly, an intense loss of redness and increase of hardness was found to take place in burger patties throughout refrigerated storage. Most fruit extracts as well as Q significantly reduced the formation of protein carbonyls and inhibited colour and texture deterioration during chill storage. Likely mechanisms through which protein oxidation could play a major role on colour and texture changes during chill storage of burger patties are discussed. Amongst the extracts, RC was most suitable for use as a functional ingredient in processed meats since it enhanced oxidative stability, colour and texture properties of burger patties with no apparent drawbacks.