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The brewing industry is regarded as a fiercely competitive and insatiable sector of activity, driven by the significant technological improvements observed in recent years and the most recent consumer trends pointing to a sharp demand for sensory enhanced beers. Some emergent and sustainable technologies regarding food processing such as pulsed electric fields (PEF), ultrasound (US), thermosonication (TS), high-pressure processing (HPP), and ohmic heating (OH) have shown the potential to contribute to the development of currently employed brewing methodologies by both enhancing the quality of beer and contributing to processing efficiency with a promise of being more environmentally friendly. Some of these technologies have not yet found their way into the industrial brewing process but already show potential to be embedded in continuous thermal and non-thermal unit operations such as pasteurization, boiling and sterilization, resulting in beer with improved organoleptic properties. This review article aims to explore the potential of different advanced processing technologies for industrial application in several key stages of brewing, with particular emphasis on continuous beer production., This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and by LABBELS—Associate Laboratory in Biotechnology, Bioengineering and Microelectromechnaical Systems, LA/P/0029/2020. Ricardo N. Pereira acknowledges FCT for its Assistant Research program under the scope of Scientific Stimulus Employment with reference CEECIND/02903/2017., info:eu-repo/semantics/publishedVersion

The development of more efficient and sustainable technologies for the recovery of valuable compounds holds the ability to change the paradigm of the use of resources. Electric field-based technologies have been regarded as highly promising towards an efficient extraction of biometabolites while addressing sustainability. Algal biomass is a potential valuable resource. Besides its nutritional value, it provides a wide range of bio compounds with a variety of industrial applications in different sectors (e.g., food, feed, cosmetics). Implementing a cascade biorefinery approach based on electric-fields application would boost the production of high-value-added products from algal biomass, opening up new opportunities for the development of a flourishing blue bioeconomy. This review paper provides an overview of the use of alternative extraction technologies in algae biomass, focusing mainly on electric field-based methodologies, suggesting cascade biorefinery approaches considering different alternative technologies depending on the target fraction, and envisaging their environmental sustainability and economic feasibility., This work was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2020, LABBELS - Associate Laboratory in Biotechnology, Bioengineering and Microelectromechanical Systems, LA/P/0029/2020, and the PhD grant reference 2021.07623.BD (Sara G. Pereira). Ricardo N. Pereira acknowledge FCT for its Assistant Research program under the scope of Scientific Stimulus Employment with reference CEECIND/02903/2017., info:eu-repo/semantics/publishedVersion

Phosphates are common additives in the meat industry. They are used to increase the water retention capacity. They act in buffering, emulsification, colour stability, inhibition of lipid oxidation, antibacterial activity and protein dispersing properties. Excessive consumption inhibits absorption of minerals, causes kidney diseases and colorectal cancer. Brewer's yeasts are sets of strains responsible for beer fermentation. Often Saccharomyces cerevisiae, which consume sucrose, maltose and maltotriose, producing ethanol and CO². Studies show that brewer's yeast as a meat food ingredient may produce the same functions as phosphate. In this study we evaluated the potential use of brewers yeast to substitute phosphate in meat products. Hams with brewers yeasts extracts were evaluated for appearance and texture properties. Comparing with control samples, with and without phosphates, and three commercial phosphate substitutes. The impact of different treatments on colour was evaluated by the difference (Delta E test) between two colours in a L*a*b* colour space. The texture properties: hardness, cohesiveness, elasticity, gumminess, chewiness and resilience were evaluated by the TPA test (Texture Profile Analysis) of double compression. Extracts were obtained through hydrothermal treatment at high temperatures, using an autohydrolysis reactor in different temperatures and extraction times (i) only with water and solvent and (ii) with sodium hydroxide as a solvent at two concentrations. They were tested at 6.5 g/kg, the phosphate concentration in the model matrix, and 13.3 g/kg, the maximum concentration indicated to be added of the commercial phosphate substitutes tested. Hams produced with brewers yeasts extracted with NaOH 1M showed no significant differences (p, info:eu-repo/semantics/publishedVersion

Although several enzymatic approaches have been applied with this intent, the sequential use of enzymes covering both cellulolytic and proteolytic activity has never been performed in seaweeds. Sequential use of these enzymes improved the overall extraction yield by up to 160%, 30% and 80% in the different seaweeds when compared to the control condition (water extraction), use of a carbohydrases cocktail alone and use of proteases alone, respectively. Regarding the proximate composition of extracts, it proved to be an efficient approach for the solubilization of carbohydrates (up to 28% in G. vermiculophylla, 66% in P. dioica, 77% in U. rigida and 35% in F. vesiculosus) and protein (up to 55% in G. vermiculophylla, 47% in P. dioica, 52% in U. rigida and 42% in F. vesiculosus). For all biomasses, the combination of enzymes induced a significant increase in antioxidant activity, not only by the increase of phenolic compounds but also by the hydrolysis of protein to peptides. Moreover, extracts from red seaweeds displayed prebiotic activity which can be ascribed to their increased content in oligosaccharides and protein/peptides. Overall, the sequential use of enzymes with different activities demonstrated to be an efficient approach for extracting functional fractions to be used as functional ingredients to improve the nutritional value (e.g. in proteins) and/or to include antioxidant and prebiotic features in the food product., This work was supported by the Portuguese Foundation for Science and Technology (FCT), under the scope of the strategic funding of UID/BIO/04469/2020 unit and LABBELS – Associate Laboratory in Biotechnology, Bioengineering and Microelectromechanical Systems, LA/P/0029/2020, by the project VALORMAR - Full valorization of marine resources: potential, technological innovation and new applications (call 10/SI/2016, reference 24517- Mobilizing R&TD Programs) co-funded by Compete 2020, Lisboa 2020, Algarve 2020, Portugal 2020 and European Union, through the European Regional Development Fund (ERDF) and by the project Bioeconorte (ref. NORTE-01-0145-FEDER-000070; co-funded by ERDF, through Norte2002). J. S. G.-D. and S.A.C. acknowledge the doctoral fellows 2021.06136. BD and SFRH/BD/144155/2019, respectively, provided by FCT. R. N. P. acknowledges FCT for its Assistant Research program under the scope of Scientific Stimulus Employment with reference CEECIND/02903/2017., info:eu-repo/semantics/publishedVersion

Emerging processing technologies are gaining importance due to ecological benefits and high extraction efficiency. Agarophytes are seaweeds highly recognized for their agar content. This work aimed at evaluating the potential of combining subcritical water extraction and moderate electric fields (MEF) for agar extraction. Different temperature and time binomials were applied, keeping the same severity factor, under subcritical water conditions with and without MEF. The influence in the agar extraction yields, its composition and technological properties was evaluated. Moderate electric fields proved to be a valuable tool in agar recovery, particularly for G. sesquipedale, improving agar's extraction yield up to 40% at 140°C in the presence of MEF. Applied treatments and extraction technologies did not affect gelling ability, rheological behaviour, structure, and molecular weight distribution of the obtained agars. Therefore, the feasibility of alternative processing technologies was demonstrated, with gains in efficiency and processing time., This work was supported by the Portuguese Foundation for Science and Technology (FCT), by the European Regional Development Fund (FEDER) and by COMPETE 2020 – Competitiveness and Internationalization Operational Program under the scope of OH2O project (POCI-01-0145-FEDER-029145; PTDC/EQU-EQU/029145/2017). The work was also supported by FCT under the scope of the strategic funding of UID/BIO/04469/2020 unit and by LABBELS – Associate Laboratory in Biotechnology, Bioengineering and Microelectromechanical Systems, LA/P/0029/2020. Sara G. Pereira acknowledges FCT for the scholarship 2021.07623.BD. Joana S. Gomes-Dias also acknowledges FCT for the PhD grant with reference 2021.06136.BD., info:eu-repo/semantics/publishedVersion

Introduction: Pectinolytic enzymes are of great importance for the clarification process of “Vinho Verde” wine must, contributing to the reduction of haze development. During the last decade, a growing body of knowledge has been established about the effects of electric fields on the activation of important food enzymes. However, the influence of electrical parameters on catalytic activity is enzyme-dependent and should be evaluated on a case-by-case basis. This work describes, for the first time, the effects of electric fields and electrical frequency on the activity of pectinase (PEC) in the accelerated clarification of “Vinho Verde” must. Method: Moderate electric fields (MEF) with intensities below 20 V/cm and at electrical frequencies ranging from 50 to 20 kHz were applied at temperatures between 15 and 35°C. Enzymatic activity was measured for 25 min, and the initial rate of reaction was determined by the coefficient of the linear plot of galacturonic acid (GAL) production as a function of time. Results: The results show that electrical frequency can increase enzymatic activity depending on temperature conditions; at 20°C and with electrical frequencies of 2 and 20 kHz, enzymatic activity increased by up to 40 and 20%, respectively, when compared with the control sample (without the application of MEF). Temperature dependence was evaluated through the Arrhenius equation, showing that energy of activation (Ea) can be reduced from 9.2 to 6.6 kJ/mol at sub-optimal temperatures for PEC activity when MEF is applied. Discussion: Electrical parameters, when combined with temperatures below 20°C, reduced pectin concentration in “Vinho Verde” wine must by up to 42% of its initial content. This emergent treatment can be integrated in relevant environmental conditions, presenting an opportunity to increase enzyme efficiency even in low-temperature conditions, which favors the winemaking process., This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit, LABBELSAssociate Laboratory in Biotechnology, Bioengineering and Microelectromechanical Systems, LA/P/0029/2020, and funded by BIOECONORTE (ref. NORTE-01-0145-FEDER-000070) with a funding body from the Norte Portugal Regional Coordination and Development Commission (CCDR-N), NORTE2020, Portugal 2020 and ESIF - European Structural and Investment Funds., info:eu-repo/semantics/publishedVersion

Moderate electric fields (MEF) technology is attracting attention in food research and innovation given its influence on macromolecules, which includes their interactions, association pathways, as well as structure formation. This chapter addresses the role of electrotechnologies and particularly of MEF in food structure, functionality and its impact on food quality, nutrition and health/well-being. The reported effects at multiple scales are revised and critically discussed based on their impacts and potential use in the development of fine-tuned structures for food systems. The potential implications and applicability of these findings in adjacent research field areas are discussed, such as the development of innovative biomaterials. Ultimately, the implication of the structural modifications imposed by MEF and the possibility to tailor food structure, from molecular to macroscopic level, are highlighted along with their repercussion in the standardization of applied electro-heating protocols towards the development of innovative functional food and concomitant impact on consumers health., This work was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and by the I&D&I AgriFood XXI project (NORTE-01-0145-FEDER-000041) co-funded by the European Regional Development Fund under the scope of Norte 2020 (Programa Operacional Regional do Norte 2014/2020), info:eu-repo/semantics/publishedVersion

During the past decade, technologies based on the application of electric fields emerged in different areas of biotechnology. Processing strategies based on the application of pulsed electric fields (PEF), moderate electric fields (MEF), and high voltage electrical discharges (HVED) in combination with their inherent thermal effectsi.e., Ohmic heating (OH) or pulsed Ohmic heating (POH)have been used to extract bioactive compounds from underrated agro-food and forestry materials, as well as from biological biomass (such as seaweeds and microalgae, for example). Recently, extraction of phenolic compounds has received increasing attention from the research community. Several classes of phenolic compounds (either simple or complex) can be found in plants, fruits, and vegetable. Polyphenols (PPs) such as curcumin, anthocyanin rich extracts from grapes, and catechin rich extracts from plants present interesting biological and functional properties and are attractive due to their potential health benefits, which can include antioxidant, antibacterial, anticancer, and antiinflammatory activities. Those molecules are also well recognized as organoleptic food enhancers, affecting color and taste properties. This chapter intends to systematically review the use of electro-based technologies in extraction of PPs addressing the most promising and successful extraction strategies, as well as to identify phenolic molecules that can present more interesting properties after their retrieval for a potential route of valorization., Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit. FCT and the European Fund for Regional Development (FEDER) and COMPETE 2020— Competitiveness and Internationalization Operational Program, under the scope of project OH2O (PTDC/ EQU-EQU/29145/2017; POCI-01-0145-FEDER-029145). ERDF Funds through the Competitiveness factors Operational program—COMPETE and by National Funds through the FCT under the project AgriFood XXI (NORTE- 01-0145-FEDER-000041)., info:eu-repo/semantics/publishedVersion

Microalgae are known to have higher photosynthetic efficiencies when compared to land-based plants. The use of microalgae biomass as a protein source is attracting attention due to its interesting protein composition and sustainable character when compared to conventional animal and plant protein-based sources. Nonetheless, the existence of a rigid cell wall is typical for most microalgae species, and this presents a serious obstacle to a higher bioaccessibility of their valuable protein fractions. Depending on the cell wall composition, the gastrointestinal digestion process itself can result in different pathways of protein absorption. It is then important to understand how microalgae cell wall structure can be affected during traditional and industrial production of its biomass once these questions are often overlooked. This review intends to fulfill this gap by addressing the major impacts of innovative sustainable processing of microalgae biomass, giving particular attention to drying operations and cellular disruption methods based on electric field application—such as pulsed electric fields (PEF) and moderate electric fields (MEF). Using microalgae biomass as food supplements at its full potential depends on its protein digestibility patterns, and subsequently their bioaccessibility and bioavailability. The importance of using in vitro gastrointestinal systems to understand the impact of innovative downstream processing of microalgae biomass will be addressed., This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and by ALGAVALOR— Lisboa-01-0247-FEDER-035234, supported by the Operational Programme for Competitiveness and Internationalization (COMPETE2020), Lisbon Portugal Regional Operational Programme (Lisboa 2020) and Algarve Regional Operational Programme (Algarve 2020) under the Portugal 2020 Partner ship Agreement, through the European Regional Development Fund+ (ERDF)., Luís Machado acknowledges FCT for its fellowship supported by doctoral advanced training (SFRH/BD/07475/2020). Ricardo N. Pereira acknowledges FCT for its Assistant Research program under the scope of Scientific Stimulus Employment with reference CEECIND/ 02903/2017., info:eu-repo/semantics/publishedVersion

Microalgae biomass is a promising raw material for several bioproducts suitable for food, energy and pharmaceutical industries. The aim of the present work was to optimize the extraction of bioactive compounds from Chlorella vulgaris using Ohmic Heating (OH). A rotatable central composite design for two factors was used to assess the effects of temperature and solvent (% ethanol in water) on lipid extraction yields and fatty acid profile. OH extraction experiments were powered by low-frequency (50 Hz) and high-frequency (25 kHz) to identify the presence of non-thermal effects and its influence on composition and bioactive properties of the generated extracts. Lipid extraction using OH was successfully optimized with the best extraction conditions found at 70 ºC for 5 min using 88 % ethanol as a solvent. No effect on the application of the electrical frequencies was observed. These conditions allowed to recover up to 87 % of lipids from biomass, polyunsaturated fatty acids (PUFAs) accounting for 43 % of the extracted lipids against 26 % of saturated fatty acids (SFAs). The fatty acid profile reveals that C16:2, C16:3, C18:2 and C18:3 correspond to the PUFAs extracted from Chlorella vulgaris. Regarding lipid extraction yields OH was statistically equivalent to conventional heating (COV); however, in terms of heating kinetics, OH reaches the required extraction temperature 5 times faster than COV. Results showed that OH has potential to be applied as a treatment for the production of Chlorella vulgaris PUFAs richextracts providing high recovery yields with reduced treatment times and less energy consumption., This study was supported by: the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and project OH2O – PTDC/EQU-EQU/029145/2017; by FEDER funds through COMPETE2020 – Programa Operacional Competitividade e Internacionalização (POCI) under the scope of Project Algavalor (POCI-01-0247-FEDER-035234; LISBOA-01-0247-FEDER-035234; ALG-01-0247-FEDER-035234) and OH2O (POCI-01-0145-FEDER-029145); AgriFood XXI R & D & I project, operation number NORTE-01-0145-FEDER-000041, co-financed by the European Regional Development Fund (FEDER) through NORTE 2020 (Northern Regional Operational Program 2014/2020). Ricardo N. Pereira acknowledge FCT for its Assistant Research contract obtained under CEEC Individual 2017. Leandro Madureira acknowledges FCT for its PhD fellowship (SFRH/BD/151474/2021) obtained under MIT Portugal Program, info:eu-repo/semantics/publishedVersion

Ohmic heating (OH) brings a promise of sustainable thermal processing by assuring high levels of heating efficiency and reduction of water consumption. It is important to gather fundamental knowledge about the way how this emerging heating method technology can affect the biological, functional, and technological properties of important molecules such as proteins during food processing. Vegetable proteins are attracting scientific interest in the food arena, mostly due to the need of a protein transition but also the most recent consumer trends. This work describes the effects of OH on structural aspects of soy protein isolate (SPI). OH was applied at different electrical frequencies (i.e. from 50 Hz to 20 kHz) and moderate electric fields (i.e. from 0 V/cm to 20 V/cm) at the onset denaturation temperature of SPI (95ºC). Different SPI fractions, such as legumins and vicilins, were identified through non-denaturing SDS-PAGE. Through fluorescence spectroscopy it was observed that frequencies below 500 Hz quenches tryptophan emission, suggesting structural rearrangements of the protein folding behavior; this effect is more pronounced with increasing electric field intensity. OH at 50 Hz resulted in a decrease of maximum intrinsic fluorescence intensity (p, info:eu-repo/semantics/publishedVersion

Vinho Verde (translates as green wine) is one of the most important and leading DOC (Denomination of Controlled Origin) product in Portugal and known worldwide by its unique aromatic profile. Pectinolytic enzymes are of the great importance in the clarification process of Vinho Verde wine must, contributing to reduce the possibility of haze formation. During last decade a growing body of knowledge have been established about the effects of electric fields as sub-lethal stress for the activation of important food enzymes. However, the influence of electric parameters is enzyme dependent, and its influence on the catalytic activity should not be generalized This works describes for the first time the effects electric field and electric frequency on the activity of a pectinase (PEC) in the accelerated clarification of Vinho Verde must. Moderate electrical fields (MEF) with intensities below 20 V/cm and at electric frequencies ranging from 50 Hz to 20 kHz, were applied at temperatures between 15 ºC and 35 ºC. Enzymatic activity was measured for 25 minutes and the initial rate of reaction was determined by coefficient of the linear plot of the galacturonic acid production of as function of time. Results have shown that electrical frequency can increase enzymatic activity depending on treatment temperature; for example, at 20 ºC and electric frequency of 2 kHz and 20 kHz, the enzymatic activity increased approximately 40 % and 20 %, respectively, when compared with control sample (without application of MEF). The temperature dependence was evaluated through Arrhenius equation showing that the energy of activation (Ea) can be reduced from 9.2 kJ.mol-1 to 6.6 kJ.mol-1 at sub-optimal temperatures for PEC activity with application of MEF. Electrical parameters when combined with treatment temperatures 20 ºC reduced up to 42 % the presence of pectin in Vinho Verde wine must contributing to its final quality. This emergent treatment brings an opportunity to increase enzyme efficiency even at low temperatures, which are necessary during winemaking process, thus bringing a vision of sustainability through the reduction of energy input and process integration in relevant environment conditions., This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit, AgriFood XXI R & D & I project, operation number NORTE-01-0145-FEDER-000041, co-financed by the European Regional Development Fund (FEDER) through NORTE 2020 (Northern Regional Operational Program 2014/2020) and Bioeno - Comércio e Serviços em Enologia Lda. Ricardo N. Pereira acknowledge FCT for its Assistant Research program under the scope of Scientific Stimulus Employment with reference CEECIND/02903/2017., info:eu-repo/semantics/publishedVersion

The development of new green and sustainable extraction technologies with low environmental impact and providing high nutritional functionalities, safety and applicability, has become relevant. Ohmic heating (OH) has emerged as a novel electric-based technology which allows high heating rates, higher selectivity of interest compounds, less energy and solvent consumption and energetically more efficient.[1,2] Ulva rigida is a green seaweed with high exploitation potential for commercial application. Its major compound of interest is ulvan, a sulfated polysaccharide present in the cell wall that has a wide range of possible applications in nutraceuticals, functional foods, agriculture and biomaterials.[3] The aim of this work was to access the feasibility of OH assisted extraction as an alternative extraction technology in the recovery of biocompounds (e.g.: polysaccharides, proteins, phenolic compounds and pigments) from Ulva rigida using different ratios of water/ethanol in different times of extraction. Extractions were made using a solid:solvent ratio of 1:30 and water/ethanol mixtures ranging from 0 to 75 % ethanol to extract different seaweeds fractions. The extractions were performed at 82 °C during 1 h, 2 h and 3 h, and the frequency was set at 25 kHz. Control extractions were made using a water bath (conventional extraction) with the same conditions, but without the presence of an electric field. Different parameters were assessed including extraction yield, lipids, ashes, moisture, total polysaccharides, protein, total phenolic compounds and pigments (chlorophylls and carotenoids) content, antioxidant activity and gelling ability. Higher extraction and ulvan-fraction yields, as well as total polysaccharides were obtained after 3 h of extraction for aqueous extracts. Total phenolic compounds, proteins and pigments content and antioxidant activity were higher for mixtures with higher amounts of ethanol. For antioxidant activity and total phenolic compounds, the 50:50 H2O/EtOH mixture under OH proved to be more efficient, with an increase up to 10 %, when compared to conventional extraction. Also, for pigments and protein content, the 25:75 H2O/EtOH mixture allowed promising results for 1 h of extraction. Gelling ability was identical in all produced extracts. As conclusion, these results showed that OH is a good alternative for a low cost and environmental-friendly extraction technology, for the recovery of bioactive compounds from green seaweeds., info:eu-repo/semantics/publishedVersion

Pigments from cyanobacteria, in special carotenoids and phycobiliproteins, have been seen with considerable interest for industrial applications due to their bioactive properties and their natural product characteristics. The extraction of these compounds is focused on the methodologies of cell disruption and on the chemical solubility of the compounds. In this study, two different methods were optimised and evaluated in terms of pigments´ extraction from the marine cyanobacterium Cyanobium sp.: a continuous pressurized solvent extraction (CPSE) system, and an electric fields-assisted extraction system based in ohmic heating (OH). For each method, a Central Composite Design (23) was performed. Optimal conditions for each extraction method were then compared to determine the best method for the extraction of pigments from Cyanobium sp. In both optimisation and comparison steps, two extracts were obtained from the same biomass: an ethanolic extract (carotenoids-targeted) and a successive water extract (phycobiliproteins-targeted). The content and profile of carotenoids and phycobiliproteins and the respective antioxidant capacity of extracts were evaluated. OH provided the best ethanolic extract, with a carotenoids content of 41.6 ± 1.7 mg gDW-1, and total antioxidant capacity of 8.0 ± 0.3 mgTE gDW-1, representing an increase of 1.3-fold and 2.5-fold respectively, when compared to CPSE. Regarding the aqueous extract, both methods led to the same content of phycobiliprotein (135 ± 10.0 mg gDW-1), although OH led to an antioxidant capacity of this extract of 8.3 ± 0.3 mgTE gDW-1, 3.6-fold higher when compared to CPSE. In terms of profile, no major variation was found between extraction methods, being lutein, zeaxanthin, echinenone and -carotene the major carotenoids (>60 % of total carotenoids), and phycocyanin and allophycocyanin the only present phycobiliproteins (in a 1:2 ratio). In addition to the productivity and composition of the extracts, the design and applicability of the system must be considered. Once again, OH overtook the other methods due to the scalability and possible continuous operation. Overall, OH proved to be the best of the two methodologies for pigments co-extraction from Cyanobium sp.., A PhD fellowship (reference SFRH/BD/136767/2018) for author Fernando Pagels was granted by Fundação para a Ciência e Tecnologia (FCT, Portugal) under the auspices of Programa Operacional Capital Humano (POCH), supported by the European Social Fund and Portuguese funds (MECTES). This work was financially co-supported by the strategical funding from FCT UIDB/04423/2020, UIDP/04423/2020 and UIDB/04469/2020; and the project ALGAVALOR – MicroALGAs: produção integrada e VALORização da biomassa e das suas diversas aplicações (POCI-01-0247-FEDER-035234), supported by the European Regional Development Fund and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte., info:eu-repo/semantics/publishedVersion

Pulsed electric fields (PEF) is attracting great attention as nonthermal extraction technology on downstream processing of emergent marine bioresources such as micro- and macroalgae. These uni- and multicellular algae enclose a diverse and interesting biochemical composition and are recognized as important sources of valuable bioactive compounds and functional food nutrients. This chapter intends to give an overview about the role of electric field processing toward the extraction of proteins and carbohydrates given particular emphasis on PEF technology, addressing the latest scientific developments in the field. Electric field-based technologies have a great potential as a green tool, being an energy efficient and environmentally friendly processing technology, while reducing the operational time by allowing a strong electro permeation, that is electroporation of cellular membranes, that enhances the extraction yields while reducing the use of solvents. The possibility of combining PEF with other processing variables (i.e., ohmic heating) can bring more flexibility to the extraction process and will be highlighted., (undefined), info:eu-repo/semantics/publishedVersion

With the increase in population and, subsequently, in food demand, the use of novel foods and ingredients is fundamental. Seaweeds are promising alternatives for the food industry due to their availability, nutritional value, wide range of macro and micronutrients and high added-value bioactive compounds [1,2]. Of equal importance is the use of more environmentally friendly processing strategies. The use of moderate electric fields is a sustainable alternative, recognized for its energy efficiency and reduced emissions, with given proof in the extraction and functionalization of algae fractions [3,4,5]. In order to fully valorise the red seaweeds Gracilaria vermiculophylla and Porphyra dioica into functional food ingredients, a series of sequential extraction procedures was applied: i) aqueous extraction (aimed at phycobiliprotein recovery); ii) ethanolic extraction (targeting chlorophyll and carotenoid recovery) and iii) hot-water extraction (for gelling polysaccharide recovery). Moreover, the effect of green alternatives (moderate electric fields) on the recovery yields and behaviour of the extracted fractions was accessed. The use of moderate electric fields allowed for an increase in the extraction yield of phycoerythrin (1.6 times), without compromising its thermal stability, alongside an increase in chlorophyll a (1.3 times) and chlorophyll b (1.8 times). Furthermore, the extracts obtained using electric fields presented a higher antioxidant activity than those obtained by conventional heating. Regarding the texturizing fractions, the use of moderate electric fields increased the gelling strength 1.3 times, without compromising the extraction yields. Lastly, the remaining solid fraction was further valorised using enzyme-assisted extractions aimed at aimed at bioactive peptide and fermentable monosaccharide recovery. Overall, the used strategy proved that it is possible to recovery functional and bioactive ingredients from red seaweeds, using more energetically sustainable processes, that can be applied as clean-label colouring and texturizing agents, alongside nutraceutical and bioactive ingredients, towards more nutritious and natural food alternatives., This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2019 unit and by COMPETE 2020 – Competitiveness and Internationalization Operational Program and the European Regional Development Fund (FEDER), under the scope of the project cLABEL+ - Innovative natural, nutritious and consumeroriented clean label foods (POCI-01- 0247-FEDER-046080) and VALORMAR – Full valorization of marine resources: potential, technological innovation and new applications (call 10/SI/2016; reference: 24517)., info:eu-repo/semantics/publishedVersion

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Ohmic heating (OH) allows a natural synergy between thermal and electrical effects, appearing as an efficient approach to the thermal extraction of biocompounds. Different electrical field intensities (e.g., 12 and 217V/cm), treatment temperatures (from 50 to 100°C) and heating strategies (continuous and pulsed heating) were combined to enhance for the first time the extraction of nutrients from microalgae Coelastrella sp. LFR1, which is highly adapted to extreme survival conditions. Results showed that OH applied at 217V/cm, through a fast and single heating pulse (OHP), and at maximum peak temperature of approximately 100°C (with, This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit, by the I&D&I AgriFood XXI project (NORTE-01-0145-FEDER-000004) co-funded by the European Regional Development Fund under the scope of Norte2020 (Programa Operacional Regional do Norte 2014/2020) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. This research work was supported by ALGAVALOR - Lisboa-01-0247- FEDER-035234, supported by Operational Programme for Competitiveness and Internationalization (COMPETE2020), Lisbon Portugal Regional Operational Programme (Lisboa 2020) and Algarve Regional Operational Programme (Algarve 2020) under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (ERDF). Vitor Sousa acknowledges the Foundation for Science and Technology (FCT) for their fellowship UI/BD/151238/2021. Luís Loureiro is recipient of a fellowship supported by a doctoral advanced training (call NORTE-69-2015-15) funded by the European Social Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. Ricardo Pereira acknowledge FCT for the Assistant Research contract obtained under CEEC Individual 2017., info:eu-repo/semantics/publishedVersion

In order to fill the nutritional needs of a growing world population, countless efforts have been made the search for new and sustainable protein sources. However, these goals may only be met by a multidisciplinary approach, covering the whole food supply chain (from farm to fork), which needs to be addressed and reconsidered. Emerging proteins are now a big trend, but in the future can these alternative protein sources become the most healthy, tasty, and viable option for consumers? Therefore, the issue is not just about the development of functional and nutritionally balanced foods, but it is also crucial to deeply analyze how those alternative protein sources could be produced/obtained sustainably, processed, and delivered to the consumer ensuring a full nutritional and functional potential available. This chapter intends to bring new insights and considerations on the future challenges for researchers in the development of healthy, sustainable, and innovative food protein solutions., (undefined), info:eu-repo/semantics/publishedVersion

Ohmic heating as an emergent food processing tehcnology. The state of art of the technology, equioments, applications and the future challenges., info:eu-repo/semantics/publishedVersion

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The chestnut (Castanea sativa Mill.) is a seasonal product that needs a post-harvest treatment to control fungal and insect worms development in order to extend its shelf-life. Studies have demonstrated the feasibility of ohmic heating (OH) and the effects of its moderate electric fields during microbiological inactivation treatments for food applications. This emerging thermal technology can be an alternative to chestnut conventional hydrothermal treatment (HT) or to its chemical fumigation. The aim of this study was to evaluate OH capacity to extend shelf-life of chestnuts fruits by eliminating its fungal load. Five treatments were carried out: I) unprocessed chestnuts (control), II) HT (50 ℃, 45 min), III) OH at 35 ºC, IV) OH at 45 ºC and V) OH at 55 °C. The ohmic processing was conducted in a 0.5 M NaCl solution at an electric field of 9 (V/cm) for 2.00, 2.83 and 3.33 min, respectively for each temperature. Then, the chestnuts were stored for 60 days under different atmospheric conditions: i) 25°C with 40% RH, ii) 25 °C with 90% RH, and iii) 5 °C with 70% RH. Once a week the chestnuts were visually inspected for fungal and insect larvae development. Additionally, fungal load of chestnuts (log CFU/g) was determined by plating serial dilutions in RBC agar. The results showed significant differences (p>0.05) in counts of fungi between unprocessed and treated samples, in particular when the storage of chestnuts was done at 5 ºC. The OH treatment conducted at 55 ºC showed the better results; at 5 ºC and 70% RH, no fungi could be detected in samples for 60 days; while at room temperature (25 ºC), no fungi were detected for 24 days. After this period, 3.8 to 5.1 log CFU/g were detected in fruits without any visible formation of molds. The HT performed better then OH at 35 ºC, but fungi could be detected after 24 days of storage at 5 ºC (3.8 to 4.9 log CFU/g). In conclusion, OH showed to be an effective alternative HT, allowing to reduce postharvest decay of chestnuts, increase its shelf-life, and thus meet foodsafety international trade regulations., info:eu-repo/semantics/publishedVersion

Vine pruning residue (VPR), a waste from the wine production, has attracted the interest of chemical and food industries thanks to its great potential as a raw material to obtain bioactive compounds. Due to the high market price of these compounds, different technologies have been studied to improve the economic profitability of their obtaining process. Therefore, the objective of this work was to evaluate an emerging technology named ohmic heating (OH) against conventional heating (CH) to extract bioactive compounds from VPR with significant antioxidant and antimicrobial activities. Extractions were carried out using a 45% hydroalcoholic solution, a solid/liquid ratio of 1/40 (g VPR/mL solvent) at 80°C for 60 min and under constant stirring. Total phenolic compounds (TPC) of the extractes were evaluated and the bioactive compounds identified and quantified by HPLC. Moreover, the antioxidant potential of the recovered compounds was estimated by the methods of DPPH, FRAP and ABTS, and the antimicrobial activity through MIC assay was tested against five food pathogenic fungi. The OH extract showed higher TPC concentration (196.2 mg GAE/kg), being identified 12 polyphenolic compounds, twice the number of compounds found in the CH extract and revealing quercetin and apigenin (2867.8 and 1574.9 mg/kg, respectively) as the main compounds in OH extract. Moreover, OH extract showed higher antioxidant activity (432.7 mg FE/kg, 370.2, 207.4 mg TE/kg for FRAP, DPPH and ABTS, respectively) and better inhibitory effects against P. expansum, Alternaria sp., Phoma violacea, and C. cladosporioides (54.5, 45.4, 33.9, 59.9%, respectively) when 1000 g/mL of extract was used. These findings demonstrated the potential of VPR extracts as a probable source of bioactive compounds with relevant functional characteristics, as well as the efficiency of OH in the extraction of polyphenolic compounds from VPR, proposing a reduction in energy consumption and making the process more environmentally friendly., Project of UID/BIO/04469/2013 CEB, info:eu-repo/semantics/publishedVersion

[Excerpt] Nanohydrogels can be considered as superabsorbent materials composed of threedimensional crosslinked polymer networks at nanoscale size. These polymeric and highly hydrophilic materials have a high swelling capacity, retaining large amounts of water (the preferential dispersion medium) within a very flexible stable structure, which can resemble a natural tissue (Ahmed 2015). Over the past few years, the interest in the development of nanohydrogel matrices has been growing, particularly in the field of biomedical sciences for drug delivery applications (Dalwadi and Patel 2015). Presently, nanohydrogels prepared from natural and biodegradable polymeric sources—i.e., proteins and polysaccharides—are establishing a strong foothold not only in medicine (e.g., cancer therapy and tissue engineering), but also in other fields of science such as agriculture and food technology, in particular for the development of functional foods, active or smart food packaging systems, and biosensing elements (Akram and Hussain 2017). Protein-based nanohydrogels are drawing huge attention due to their biological value and different possibilities of structural design, which offers an innumerous potential for the encapsulation, association, or biocomplexation with active ingredients. [...], (undefined), info:eu-repo/semantics/publishedVersion

This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2019 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. This work was also supported by FCT and POCI through project AlleRiskAssess (POCI-01-0145-FEDER-031720 – PTDC/BAA-AGR/31720/2017). C. Villa is grateful to FCT grant (PD/BD/114576/2016) financed by POPH-QREN (subsidised by FSE and MCTES). R. Rodrigues is grateful to FCT grant with reference SFRH/BD/110723/2015., info:eu-repo/semantics/publishedVersion

Nanoencapsulation in the Food Industry series, vol.1, The most current and high-level research is being taken on the use of nanoscience and nanotechnology due to its varied application in numerous fields of science. Food nanotechnology, and in particular, the development and application of bio-based nanostructures are an emerging area having a high potential to engender new products and processes in the food industry. This chapter intends to discuss whey protein-based nanostructured systems (i.e., whey protein isolate, whey protein concentrate, -lactoglobulin, and -lactalbumin) for encapsulation of food ingredients. These protein nanostructures have unique properties, such as a high nutritional value, GRAS nature, gelling capability, and can be easily prepared and controlled. They have also the ability to conjugate a large variety of food ingredients (e.g., antioxidants, vitamins, minerals, flavors, and odors) via amino groups or ionic and hydrophobic interactions. This behavior will prevent the degradation of sensitive bioactives, while permitting a site-specific action and controlled delivery rate due to the swelling behavior of the gel in reaction to external and physical stimuli such as temperature, enzymes, pH, or ionic strength), thus contributing to an improved bioavailability of such ingredients. The potential of whey protein nanostructures for encapsulation and controlled delivery of food ingredients will be addressed in a critical manner in this chapter. Moreover, various techniques used for their nanoencapsulation and evaluation of their stability during storage will also be discussed. The behavior and bioavailability of whey nanostructures and their associated/encapsulated food ingredients will be discussed using insights from in vitro and in vivo gastrointestinal systems together with potential cytotoxicity, cellular uptake, and allergenicity via in vitro cell lines. Finally, examples of such nanostructures applied in food matrices will be described, as well as the main challenges for their commercial use., FCT, CNPq, COMPETE 2020, NORTE 2020, Oscar L. Ramos, and Ricardo N. Pereira acknowledge their Post-Doctoral grants (SFRH/BPD/ 80766/2011 and SFRH/BPD/81887/2011, respectively) and Daniel A. Madalena and Rodrigues R. Martins acknowledge their Doctoral grants (SFRH/BD/129127/2017 and SFRH/BD/ 110723/2015, respectively) to the Fundação para a Ciência e Tecnologia (FCT, Portugal). Lívia S. Simões gratefully acknowledges her grant to CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico, Brasil) from Brazil. This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/Multi/50016/2019 and UID/BIO/04469 units and COMPETE 2020 (POCI-01-0145- FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte., info:eu-repo/semantics/publishedVersion

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Ohmic heating (OH) is establishing a solid foothold in the innovative food processing due to its fast, direct and volumetric heating with remarkable implications in food quality, safety (i.e. non-thermal microbial inactivation) and energy efficiency. Over the last decade novel insights have been brought about the interactions of electric variables such as electric field intensity and electrical frequency on dynamic behaviour of important food proteins during their thermal denaturation process. Protein richfractions of beta-lactoglobulin (b-LG) has been used as model to evaluate conformational transitions, distribution of secondary structures and aggregation patterns imposed by different electric field processing protocols. It is now an evidence that combined effects of electrical and thermal treatments brought by OH can reduce thermal denaturation and aggregation of b-LG but also interfere with their unfolding transitions and protein-protein interaction properties, giving rise to aggregates with different morphologies and distinct physical and chemical internal networks. Knowing that a great majority of important food proteins are elicitors of allergic reactions, is then essential to understand the implications that the non-thermal effects of electric fields have on the potential allergenicity of the food proteins. There is a lack of research regarding the impact of OH on immunoreactivity of proteins, and the outcomes of traditional thermal processing should not be automatically assumed due to internal heating (i.e., different levels of thermal load) and effects of electric fields on biophysical state of proteins. Our findings unravel that OH brings a new paradigm for the thermal denaturation of protein-rich fractions with potential to change resilience of protein aggregated structures to gastrointestinal digestion, which can bring potential consequences on allergic response during intestinal absorption that need to be thoroughly assessed. Acknowledgments This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2019 unit and BioTecNorte operation (NORTE-01- 0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 Programa Operacional Regional do Norte., This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2019 unit and BioTecNorte operation (NORTE-01- 0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 – Programa Operacional Regional do Norte., info:eu-repo/semantics/publishedVersion

This work was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01- 0145-FEDER-006684) and by BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 – Programa Operacional Regional do Norte. Enrique Pino Hernández is recipient of a fellowship supported by a doctoral advanced training (call NORTE-69-2015-15), funded by the European Social Fund under the scope of Norte2020 – Programa Operacional Regional do Norte., info:eu-repo/semantics/publishedVersion

The authors would like to thank to the project Co-promoção nº 016403, “MULTIBIOREFINERY”, supported by Programa Operacional Competitividade e Internacionalização e pelo Programa Operacional Regional de Lisboa, na sua componente FEDER, e pela Fundação para a Ciência e Tecnologia and project UID/Multi/50016/2013, administrated by FCT. Furthermore, his study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2019 unit and BioTecNorte operation (NORTE-01- 0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. The author Marta Coelho would like to acknowledge FCT for your PhD grant with the reference [grant number SFRH/BD/111884/2015] ., info:eu-repo/semantics/publishedVersion

Semana de Ciência e Tecnologia 2008 - O CEB na Escola Secundária de Barcelos, info:eu-repo/semantics/publishedVersion

Background & Objectives: Electrospray is a methodology able to create nanocapsules, as wel l as to encapsulate and dry in only one-step process. In this work the electrospray was used to produce nanocapsules based on whey protein isolate (WPI) loaded with beta-carotene as lipophilic model compound. Method(s) and Results: WPI solutions of 18% (w/v) were prepared in aqueous solutions with 5, 10 and 15% (v/v) of ethanol, which was used for beta-carotene solubilization (0.02 mg/ml). The optimized electrospray conditions were: 20 kV, 0.5 mUh and using a needle with an inner diameter of 1.422 mm. The morphology and molecular organization of the nanocapsules were studied in dried and hydrated state. The size of the dried nanocapsules (determined by SEM) ranged between 227 and 283 nm. After hydration, the nanocapsules (determined by DLS and TEM) showed an average size higher than the dried ones, which increased for nanocapsules produced using higher ethanol concentrations. Results, obtained from the reactivity of free sulfhydryl groups and fluorescence analysis, showed that the increase of ethanol concentration had an effect on the protein unfolding, while for samples with the presence of beta-carotene is observed a decrease in sulfhydryl groups, which is explained by the interaction of beta-carotene with protein hydrophobic region. Conclusions: The results showed that WPl-based capsules can be obtained by electrospray and used for the encapsulation of beta-carotene., This work was supported by the project ARMAdilhas seletivas para eliminação da VESPA velutina. Medida 6 - lnvestigação e Desenvolvimento (n2 5894057). lnstituto de Financiamento de Agricultura e Pescas, l.P, info:eu-repo/semantics/publishedVersion

Seaweeds are important marine resources in Portugal, being mostly applied in the hydrocolloids industry or as food. Emerging applications include the production of high added-value bioactive compounds. Seaweed polysaccharides are water-soluble biopolymers and have a linear backbone composed of sugar units conjugated to form complex structures. The –OH groups, predominant in the polymeric chains can establish intra- and intermolecular hydrogen bonds which are excellent functional tools for gel and/or film-formation. Agar is extracted mainly from red seaweeds from Gelidiales and Gracilariales (in which group Gracilaria sp. are included). In the case of agar from Gracilaria sp., normally with inferior commercial characteristics, the functional properties are usually enhanced by an alkali pre-treatment that modifies the L-galactose-6-sulphate units into 3,6-anhydro-α-Lgalactose residues. Traditional hot water extraction is a tedious process, requires high solvent and energy consumptions and generates large amounts of waste creating the need for greener and more efficient technologies. The main objective of this work is to evaluate the influence of different electric fields intensity in the performance of the agar’s extraction from Gracilaria sp. in terms of yield, extraction time and extract’s quality., info:eu-repo/semantics/publishedVersion

As caseínas, β- lactoglobulina e α- lactalbumina são as principais proteínas do leite. Quando aquecidas, acima de determinada temperatura, as proteínas globulares agregam-se devido à exposição e agregação de grupos hidrofóbicos, porém na presença de caseínas esta agregação pode ser menor devido à interação entre tais proteínas e as caseínas. Neste trabalho foi observada menor agregação das proteínas sob aquecimento a campos elétricos moderados (4 e 7 V cm-1) possibilitando o uso desta tecnologia para o controle da agregação de proteínas globulares e permitindo vislumbrar a manufatura de produtos com características diferenciadas., info:eu-repo/semantics/publishedVersion

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The application of micro- and nanotechnologies in the food industry have been widely studied and reported due to an increasing growth of public awareness for the consumption of healthy food products. Consequently, food industry players have become highly interested in the development and application of innovative food-grade micro- and nanosystems intended for the protection and controlled delivery of bioactive compounds. This can be achieved by resorting to novel state of the art methodologies (i.e., top-down and bottom-up strategies) that take advantage of the functional properties of such ingredients, so that they can be used to protect and release, in a controlled manner, bioactive compounds. To evaluate effectiveness of these micro- and nanosystems it is of utmost importance to evaluate their behavior when incorporated in food products, in order to perceive potential interactions with biomolecules, as well as under gastrointestinal (GI) digestion. In vitro \GI\ models have been used since they provide accurate results, are relatively inexpensive, and do not raise ethical issues, and most of all can be correlated with those obtained in vivo., Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) and by BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 – Programa Operacional Regional do Norte. Daniel A. Madalena, Ricardo N. Pereira and Oscar L. Ramos are recipient of a fellowship supported by FCT (SFRH/BD/129127/2017, SFRH/BPD/81887/2011 and SFRH/ BPD/80766/2011, respectively), info:eu-repo/semantics/publishedVersion

Bio-based packaging has undergone a remarkable growth in recent years due to great advances in materials science and processing technology, and is expected to have a major impact on the food market in the near future. Food packaging is used as barrier, but also to maintain quality and safety during food product transport and storage, to extend shelf life and add nutritional value. With this goal, the use of bio-nanocomposites appears as a promising solution to improve the properties of existing biopolymer-based packaging materials, and for development of novel functionalities, while permitting replacement of nonbiodegradable plastic packaging materials. This chapter provides an overview of the latest food packaging evolutions and expectations of forthcoming developments involving the use of bio-based nanocomposites in biodegradable packaging. Food protection, safety, environmental and health concerns, interest in developing biodegradable and renewable materials for food packaging, and applications of nanomaterials and nanotechnologies will be duly addressed., Oscar L. Ramos, Ricardo N. Pereira, and Joana T. Martins gratefully acknowledge their post-doctoral grants (SFRH/BPD/80766/2011, SFRH/BPD/81887/2011, and SFRH/BPD/89992/2012, respectively) to the Fundação para a Ciência e Tecnologia (FCT, Portugal). The authors thank the FCT Strategic Project of UID/BIO/04469/2013 unit, COMPETE 2020 (POCI-01-0145-FEDER-006684), and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020—Programa Operacional Regional do Norte, as well as the project POCI-01-0145-FEDER-006939 (Laboratory for Process Engineering, Environment, Biotechnology and Energy—LEPABE) funded by FEDER funds through COMPETE2020—Programa Operacional Competitividade e Internacionalização (POCI)—and by national funds through FCT., info:eu-repo/semantics/publishedVersion

projects Co-promoção nº 016403, NORTE-01-0145-FEDER-000004 and OCI-01 -0145-FEDER-006684. Furthermore, the authors would also acknowledge the FCT projects, SFRH/BD/111884/2015, SFRH/BPD/81887/2011, UID/BIO/04469/2013 and the scientific collaboration of CBQF under the FCT project UID/Multi/50016/2013, info:eu-repo/semantics/publishedVersion

Book of Abstracts of CEB Annual Meeting 2017, [Excerpt] Several technologies utilizing electrical fields directly into food processing, such as pulsed electric fields and ohmic heating, are currently being used on a commercial scale for of an extensive range of food products. They have shown to be environmentally clean technologies (at least locally), that can bring added-value to the products, improving the overall energy efficiency of the process and reducing the use of non-renewable resources [1]. During the last decade, much research on ohmic heating and the effects of its moderate electric fields has been addressed with a view to combating pathogens and improving the nutritional and sensorial properties of thermal processed food. Recently it has been demonstrated that electro-heating appears also as an interesting processing tool to be used in extraction of bioactive compounds from food by-products, as well as a way to modulate functional and technological aspects of important food ingredients, such as whey proteins. [...], info:eu-repo/semantics/publishedVersion

The 19th Gums & Stabilisers for the Food Industry Conference: Hydrocolloid multifunctionality, β-Lactoglobulin (β-Lg) is the major protein fraction in bovine whey serum (ca. 50% of its protein content). It is a bio-based and a Generally Recognized As Safe (GRAS) material, with a high nutritional value, that can be used to encapsulate nutraceuticals essentially due to its gelation capacity, which allows the formation of nanohydrogels. Furthermore, β-Lg displays a high binding capacity, under specific environmental conditions and it is resistant to proteolytic degradation in the stomach. These features make of β-Lg an excellent bio-based material to be used as carrier of nutraceuticals. The objective of this work was to understand the impact of different conditions (β-Lg concentration and heating times) in the physical properties of β-Lg nanohydrogels. In this study, β-Lg at various concentration (5, 10 and 15 mg·mL-1 ), were solubilized in 25 mM of sodium phosphate buffer (at pH 6) and heated at 80 °C for several holding time periods (5, 15 and 25 min). The protein structures formed were then characterized in terms of their stability, morphology, polydispersity index, size and surface charge. Stable nanohydrogels were obtained at pH 6, when treated at 80 ºC for heating periods longer than 15 min, characterized by a low polydispersity (< 0.2). At these conditions, nanohydrogels showed increasing particle size values, ranging from 50 nm to 110 nm, and surface charge from -15 mV to -20 mV, as β-Lg concentration increased. Nanohydrogels prepared at the same conditions, but treated for shorter periods of time, showed to be unstable, characterized by higher polydispersity (≥ 0.5) and surface charges of - 7 mV, independently of the β-Lg concentration used. The results obtained in this study represent a significant contribute to enrich the knowledge about the impact of several environmental conditions on β-Lg nanohydrogel characteristics and thus in the desired properties intended for their final application., Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI - 01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte 2020 - Programa Operacional Regional do Norte, info:eu-repo/semantics/publishedVersion

The 19th Gums & Stabilisers for the Food Industry Conference: Hydrocolloid multifunctionality, Ohmic heating is currently being used by food industry as an alternative for the conventional thermal processing of several types of foods. Thus, the way how electrical fields affect functional and nutritional aspects of important food ingredients still needs to be ascertained. During the last decade, the effects of electro-heating treatments and its moderate electric fields (MEF) has been addressed with a view to functionalize whey protein systems. Whey proteins present an interesting set of technological, functional and biological properties being thus considered as an important dietary food ingredient. In this research it was demonstrated that MEF appears an interesting processing tool acting like a chaperon towards heat unfolding, aggregation and gelation of whey proteins. Results show that the presence of electro-heating contributes to a thermodynamic change in protein denaturation kinetics leading to lower values of reaction order (n) and rate constant (k) (p < 0.05), when compared to those of conventional heating under equivalent heating rates and holding times. Application of MEF provides also a fast, homogenous and direct way of heating (Joule effect) reducing the size of protein aggregates from 300 nm to 170 nm (p < 0.05), and thus affecting thermal aggregation and also morphology of protein aggregates. Transmission electron microscopy (TEM) discloses the appearance of small fibrillar structures at nano-scale size (< 200 nm) upon the influence of MEF. These fibril-like structures have recognized potential to form hydrocolloid gels, act as thickeners in foods or be also used as carrier for the transport of bioactive or functional ingredients. Electro-heating treatment can be designed together with gelation at room temperature induced by salt addition (also known by cold gelation) for the development of entirely biodegradable whey protein isolate gel as potential carrier of divalent iron (Fe2+). Results have shown that ca. 33 mmol.L 1 of Fe2+ can be associated to a WPI gel network. Application of MEF provides an opportunity for the development of innovative functional foods that can be used as an oral dietary supplement., info:eu-repo/semantics/publishedVersion

IFT 2017 Annual Meeting and Food Expo, [Excerpt] Introduction: β-lactoglobulin (β-Lg) is the major globular protein in milk and the dominant functional agent in whey and its derivatives ingredients. It is generally recognized that β-Lg undergoes conformational changes above temperatures of 60 °C and unfolds irreversibly after 70 °C. The conformational changes that happen during this process have critical implications in β-Lg functional properties, thus affecting both technological quality of milk (i.e. cheese production) and whey ingredients, which use are currently widespread in food formulations. In this study thermal effects in β-Lg have been investigated through an innovative approach, combining on-line spectroscopy techniques, aiming at achieving a more detailed characterization of these events below and above the melting temperature. [...], This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. The authors Rui M. Rodrigues, Ricardo N. Pereira, also thank to FCT their financial grants with SFRH/BD/110723/2015, SFRH/BPD/81887/2011 respectively., info:eu-repo/semantics/publishedVersion

Vienna Polyphenols 2017 - 11th World Congress on Polyphenols Applications, [Excerpt] Introduction: Tomato based products is one of the worldwide major agroindustrial sectors generating substantial amounts of wastes, with high economic and environmental costs[1]. These agroindustrial by-products e.g. skins and pulp remnants, are rich in bioactive compounds such as polyphenols [2–4]. Current extraction treatments, besides representing environmental hazards, may cause these by-products bioactive compounds degradation, promote toxicity, and reduce biological properties and health benefits, thus hampering their added value. Therefore, there is a growing interest in alternative extraction technologies, such as the case of Ohmic Heating (OH), an environmentally-friendly technique (i.e. use of electrical energy) [5]. This study aimed to optimize the extraction of phenolic compounds, antioxidants and carotenoids of tomato wastes through ohmic heating, as an alternative extraction technology. [...], The authors would like to thank to the project Co-promoção nº 016403, “MULTIBIOREFINERY”, supported by Programa Operacional Competitividade e Internacionalização e pelo Programa Operacional Regional de Lisboa, na sua componente FEDER, e pela Fundação para a Ciência e Tecnologia and project UID/Multi/50016/2013 , administrated by FCT. Furthermore, This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte”The author Marta Coelho would like to acknowledge FCT for your PhD grant with the reference [grant number SFRH/BD/111884/2015] and Ricardo Pereira SFRH/BPD/81887/2011., info:eu-repo/semantics/publishedVersion

BioTech 2017 and 7th Czech-Swiss Symposium with Exhibition, [Excerpt] Moderate Electric Fields (MEF) provide a uniform, rapid and energetically very efficient means of processing foods (mostly by heat). This has been known for over a century and has finally found its place among food processors, as MEF industrial equipments are being installed worldwide in growing numbers and in a variety of applications. This happened after technological issues such as electrode corrosion and adequate temperature and power control systems were solved. [...], info:eu-repo/semantics/publishedVersion

Current extraction treatments may cause degradation of biocompounds hampering their added value. Phenolic compounds extraction of Lycopersicon esculentum (tomato) by-products was optimized using ohmic heating (OH) as an alternative extraction technology. Design of experiments was applied to evaluate the effect of extraction time, temperature and ethanol concentration and further optimized by a desirability function. The antioxidant activity and characterization of phenolic compounds was performed. A significant increase of phenolics content and antioxidant activity were obtained at 70ºC and 40ºC (p, The authors would like to thank to the project Co-promoção nº 016403, “MULTIBIOREFINERY”, supported by Programa Operacional Competitividade e Internacionalização e pelo Programa Operacional Regional de Lisboa, na sua componente FEDER, e pela Fundação para a Ciência e Tecnologia and project UID/Multi/50016/2013, administrated by FCT. Furthermore, This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POC-01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145--FEDER-000004) funded by European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte”. The author Marta Coelho would like to acknowledge FCT for your PhD grant with the reference [grant number SFRH/BD/111884/2015] and Ricardo Pereira SFRH/BPD/81887/2011., info:eu-repo/semantics/publishedVersion

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Ohmic Heating (OH) and its associated non-thermal effects due to the presence of an electrical field and frequency has been triggering the use of this technology for whey protein functionalization. Whey proteins have increasingly been used as functional ingredients in several food formulations presenting high nutritional and biological value (i.e., digestibility, amino acid pattern, and sensory characteristics). The purpose of this study was to characterize early steps of whey protein isolate denaturation and aggregation kinetics under the influence of OH treatments by combining different thermal and electrical effects. A multivariate characterization was performed in order to identify a global pattern in denaturation behaviour of WPI under OH applied by linking different structural stages, such as protein unfolding, exposure of protein hydrophobic core, loss of protein solubility and formation of protein aggregates. Results shows that exposure of reactive free thiol groups involved in molecular unfolding of β-lactoglobulin (β- lg) can be reduced from 10 to 20 % with OH. The presence of a moderate electric field (up to 12 V/cm) during heating also contributes to a change in the protein aggregation kinetics, as well as in the shape of the produced whey aggregates. Size growth was significantly reduced from 178 nm to 25 nm (p < 0.05) under influence of OH and transmission electron microscopy (TEM) discloses the appearance of β-lg small fibrillar aggregates upon the influence of OH. As conclusion, OH and its capability of fast heating coupled with treatments under relatively low electrical field strength, contributed to a synergistic effect yielding protein solutions with less protein aggregates and high amount of soluble proteins during early stages of heating. These fibril aggregates have a recognized potential to form physical gels, acting as thickeners or gelling agents in foods, and can be also used for encapsulation of bioactive ingredients. OH provide a novel method for production of a whey protein matrix with distinctive features and gel-forming properties.

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