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- A pilot plant scale testing of the application of seaweed-based natural coating and modified atmosphere packaging for shelf-life extension of fresh-cut applePublication . Augusto, Ana; Miranda, Andreia; Costa, Leonor; Pinheiro, Joaquina; Campos, Maria J.; Raimundo, Délio; Pedrosa, Rui; Mitchell, Geoffrey; Niranjan, Keshavan; Silva, Susana F.J.Codium tomentosum hydroethanolic extract was obtained using a pilot solid–liquid extractor to validate the anti-browning functionality of the extract under industrial conditions. Fresh-cut apple slices were coated by immersion in: (1) a seaweed extract solution (0.5% w/v) and (2) a commercial coating, and the two sets of samples were compared with a control (immersion in water). Packaged samples were stored, under ambient and modified atmosphere conditions at 4°C. After 30 days of storage, the samples that were coated with the seaweed extract and packaged under modified atmosphere, demonstrated lower peroxidase activity and polyphenol oxidation when compared with the samples treated with the commercial additive. These results confirm, at pilot scale and under industrial production conditions, the efficacy of the seaweed extract as a bio-based substitute for the synthetic coatings, which are currently used to prevent browning in fresh-cut apples.
- Effect of different drying temperatures on the moisture, content of phytochemical constituents and technological properties of Peniche coast seaweedsPublication . Augusto, Ana; Nunes, Paulo M.; Mendes, Susana; Afonso, Clélia; Mouga, Teresa
- Preservation of fresh-cut Rocha Pear using Codium tomentosum extractPublication . Augusto, Ana; Miranda, Andreia; Crespo, Daniel; Campos, Maria J.; Raimundo, Délio; Pedrosa, Rui; Mitchell, Geoffrey; Niranjan, Keshavan; Silva, Susana F.J.Rocha is a Portuguese pear cultivar with high economic importance in the Portuguese Western Region. Degradative processes following its manipulation can quickly lead to product rejection, especially when sold as a freshcut product. The efficacy of a marine-based edible coating to inhibit superficial browning development in freshcut Rocha pear slices was investigated over a storage period of 15 days. The aqueous extract of Codium tomentosum, an edible green seaweed, was incorporated in an edible coating (0.5 g 100 mL -1) for fresh-cut Rocha pear. This novel treatment effect on the quality parameters of the pears was compared with a commercial coating currently used by industry and a control (dipping in deionised water). After 15 days storage at 4 ◦C, samples treated with the seaweed extract exhibited fewer colour changes and lower rates of superficial browning than control and commercial samples. Seaweed extract treatment was also observed to inhibit yeast and mould development, which may further contribute to shelf-life extension.
- Preservation of fresh-cut Rocha Pear using Codium tomentosum extractPublication . Augusto, Ana; Miranda, Andreia; Crespo, Daniel; Campos, Maria J.; Raimundo, Délio; Pedrosa, Rui; Mitchell, Geoffrey; Niranjan, Keshavan; Silva, Susana F.J.Rocha is a Portuguese pear cultivar with high economic importance in the Portuguese Western Region. Degradative processes following its manipulation can quickly lead to product rejection, especially when sold as a freshcut product. The efficacy of a marine-based edible coating to inhibit superficial browning development in freshcut Rocha pear slices was investigated over a storage period of 15 days. The aqueous extract of Codium tomentosum, an edible green seaweed, was incorporated in an edible coating (0.5 g 100 mL -1) for fresh-cut Rocha pear. This novel treatment effect on the quality parameters of the pears was compared with a commercial coating currently used by industry and a control (dipping in deionised water). After 15 days storage at 4 ◦C, samples treated with the seaweed extract exhibited fewer colour changes and lower rates of superficial browning than control and commercial samples. Seaweed extract treatment was also observed to inhibit yeast and mould development, which may further contribute to shelf-life extension.
- Desenvolvimento de revestimentos comestíveis para produtos de IV gamaPublication . Augusto, Ana; Silva, Susana Filipa Jesus; Pedrosa, Rui Filipe PintoO sector dos produtos hortofrutícolas prontos a consumir está em constante crescimento devido a uma procura emergente dos consumidores por produtos inovadores. Novas técnicas para manter a qualidade dos produtos minimamente processados (PMP) ou de IV gama são exigidas em todas as etapas da cadeia de produção e distribuição de PMP. A maçã minimamente processada caracteriza-se por apresentar um elevado nível de escurecimento enzimático e alterações de textura ao longo do tempo de armazenamento. Dada a importância da produção de maçã minimamente processada com qualidade e com um tempo de prateleira de maior duração, o presente trabalho teve como objetivo principal o desenvolvimento de um revestimento alimentar de origem biológica para aplicação em maçãs de IV gama. Para o efeito foram utilizados quatro revestimentos formulados com adição de extratos de algas (0,5%; Fusucs spiralis, Bifurcaria bifurcata, Codium tomentosum e Codium vermilara), um revestimento com adição de ácido cítrico (0,5%) e um controlo (água destilada). Os revestimentos foram aplicados por imersão, utilizando maçã Fuji minimamente processada (fatiada). Ao longo de 20 dias de armazenamento a 4 ± 2°C foram efetuadas várias análises físicas e químicas às maçãs para poder avaliar o efeito dos revestimentos na manutenção da qualidade do produto. O revestimento que apresentou melhores resultados revelou ser a formulação com extrato da alga Codium tomentosum. A aplicação deste revestimento permitiu menores alterações das características físicas e químicas das fatias de maçã, principalmente na manutenção da cor, impedindo um índice de escurecimento significativo. O extrato da alga Codium tomentosum foi depois incorporado em dois filmes edíveis, um com 1% de alginato e outro com 1% de quitosano, aos quais foram testadas características físicas e antibacterianas. Os filmes formulados por quitosano e extrato de alga foram os que apresentaram melhores características físicas, nomeadamente maior resistência à perfuração, elevada elasticidade e ainda baixa absorção de água. A aplicação futura de filmes e/ou revestimentos de quitosano e extrato de alga em PMP poderá assim apresentar-se como uma alternativa vantajosa para a conservação deste tipo de produtos.
- A pilot plant scale testing of the application of seaweed-based natural coating and modified atmosphere packaging for shelf-life extension of fresh-cut applePublication . Augusto, Ana; Miranda, Andreia; Costa, Leonor; Pinheiro, Joaquina; Campos, Maria J.; Raimundo, Délio; Pedrosa, Rui; Mitchell, Geoffrey; Niranjan, Keshavan; Silva, Susana F. J.Codium tomentosum hydroethanolic extract was obtained using a pilot solid–liquid extractor to validate the anti-browning functionality of the extract under industrial conditions. Fresh-cut apple slices were coated by immersion in: (1) a seaweed extract solution (0.5% w/v) and (2) a commercial coating, and the two sets of samples were compared with a control (immersion in water). Packaged samples were stored, under ambient and modified atmosphere conditions at 4°C. After 30 days of storage, the samples that were coated with the seaweed extract and packaged under modified atmosphere, demonstrated lower peroxidase activity and polyphenol oxidation when compared with the samples treated with the commercial additive. These results confirm, at pilot scale and under industrial production conditions, the efficacy of the seaweed extract as a bio-based substitute for the synthetic coatings, which are currently used to prevent browning in fresh-cut apples. Novelty impact statement Fresh-cut fruits are subjected to processing operations leading to a decrease in nutritional and organoleptic properties. It is therefore necessary to adopt strategies to delay the degradative processes. In this study, the efficacy of a pilot-scale production and industrial application of a coating formulated with Codium tomentosum seaweed extract has been established for the first time. This seaweed extract possesses the potential to prevent browning development in fresh-cut apples under industrial operating conditions.
- Seaweed extracts to control postharvest phytopathogenic fungi in Rocha pearPublication . Toledo, Eloísa; Félix, Carina; Vicente, Tânia F. L.; Augusto, Ana; Félix, Rafael; Toledo, Bernardo; Silva, Joana; Trindade, Carina; Raimundo, Délio; Lemos, Marco F.L.Fungal infections cause losses amounting to between 20 and 25% of the fruit industry’s total outcome, with an escalating impact on agriculture in the last decades. As seaweeds have long demonstrated relevant antimicrobial properties against a wide variety of microorganisms, extracts from Asparagopsis armata, Codium sp., Fucus vesiculosus, and Sargassum muticum were used to find sustainable, ecofriendly, and safe solutions against Rocha pear postharvest fungal infections. Alternaria alternata, Botrytis cinerea, Fusarium oxysporum, and Penicillium expansum mycelial growth and spore germination inhibition activities were tested in vitro with five different extracts of each seaweed (n-hexane, ethyl acetate, aqueous, ethanolic, and hydroethanolic). An in vivo assay was then performed using the aqueous extracts against B. cinerea and F. oxysporum in Rocha pear. The n-hexane, ethyl acetate, and ethanolic extracts from A. armata showed the best in vitro inhibitory activity against B. cinerea, F. oxysporum, and P. expansum, and promising in vivo results against B. cinerea using S. muticum aqueous extract were also found. The present work highlights the contribution of seaweeds to tackle agricultural problems, namely postharvest phytopathogenic fungal diseases, contributing to a greener and more sustainable bioeconomy from the sea to the farm.
- Argan oil as a rich source of linoleic fatty acid for dietetic structured lipids productionPublication . Simões, Tiago; Ferreira, Jessica; Lemos, Marco F.L.; Augusto, Ana; Félix, Rafael; Silva, Susana F.J.; Ferreira-Dias, Suzana; Tecelão, CarlaArgan oil is rich in long-chain unsaturated fatty acids (FA), mostly oleic and linoleic, and natural antioxidants. This study addresses the production of low-calorie structured lipids by acidolysis reaction, in a solvent-free system, between caprylic (C8:0; system I) or capric (C10:0; system II) acids and argan oil, used as triacylglycerol (TAG) source. Three commercial immobilized lipases were tested: Novozym® 435, Lipozyme® TL IM, and Lipozyme® RM IM. Higher incorporation degree (ID) was achieved when C10:0 was used as acyl donor, for all the lipases tested. Lipozyme® RM IM yielded the highest ID for both systems (28.9 +- 0.05 mol.% C10:0, and 11.4 +- 2.2 mol.% C8:0), being the only catalyst able to incorporate C8:0 under the reaction conditions for biocatalyst screening (molar ratio 2:1 FA/TAG and 55ºC). The optimal conditions for Lipozyme® RM IM in system II were found by response surface methodology (66ºC; molar ratio FA/TAG of 4:1), enabling to reach an ID of 40.9 mol.% of C10:0. Operational stability of Lipozyme® RM IM in system II was also evaluated under optimal conditions, after eight consecutive 24 h-batches, with biocatalyst rehydration between cycles. The biocatalyst presented a half-life time of 103 h.
- Electrospun polycaprolactone (PCL) degradation: An in vitro and in vivo studyPublication . Dias, Juliana R.; Sousa, Aureliana; Augusto, Ana; Bártolo, Paulo J.; Granja, Pedro L.Polycaprolactone (PCL) is widely used in tissue engineering due to its interesting properties, namely biocompatibility, biodegradability, elastic nature, availability, cost efficacy, and the approval of health authorities such as the American Food and Drug Administration (FDA). The PCL degradation rate is not the most adequate for specific applications such as skin regeneration due to the hydrophobic nature of bulk PCL. However, PCL electrospun fiber meshes, due to their low diameters resulting in high surface area, are expected to exhibit a fast degradation rate. In this work, in vitro and in vivo degradation studies were performed over 90 days to evaluate the potential of electrospun PCL as a wound dressing. Enzymatic and hydrolytic degradation studies in vitro, performed in a static medium, demonstrated the influence of lipase, which promoted a rate of degradation of 97% for PCL meshes. In an in vivo scenario, the degradation was slower, although the samples were not rejected, and were well-integrated in the surrounding tissues inside the subcutaneous pockets specifically created.
- Changes in fatty acid profile and chemical composition of meagre (Argyrosomus regius) fed with different lipid and selenium levelsPublication . Simões, Tiago; Fonseca, Sthelio B.; Augusto, Ana; Granada, Luana; Ozório, Rodrigo O. A.; Gonçalves, Jose F. M.; Pascoal, Leonardo A. F.; Silva, José H. V.; Lemos, Marco F. L.This studyaimed to evaluatechangesin body composition, speciallymuscleandliver fatty acid profileinmeagre (Argyrosomus regius) fed with different dietary lipid sources and levels, with or without selenium supplementation. Six hundred meagre were fed twice a day, 6 days per week, with eight experimental diets for 60 days. Diets were a combination of fish oil or a vegetable blend (45% linseedþ 35% rapeseedþ 20% soybean oil), at 12 or 17% of oil and 0 or 1 mg/kg of organic selenium, in a 2 2 2 factorial design. The whole body protein and lipid content were affected by the dietary oil source. Fish oil diets increased long-chain (LC) PUFAs content in the edible tissues, while vegetable oil-based diets increased short-chain (SC) PUFAs. Vegetable oil diet tended to decrease thefish proteincontent.A higherlipidlivercontentwas observedinmeagre fed the vegetable oil blend. The results also suggested the ability of meagre to convert SC-PUFA to LC-PUFA when the vegetable oilisincludedin their diet. The possibility for partial substitution offish oil by vegetable oilin meagre diets, resulting in lower dependence of fish oil in meagre farming, is also demonstrated here