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The aim of this work was to examine for the first time the use of high-pressure assisted thermal processing (PATP) (100, 350, 600 MPa; 100 °C; 3 min) at pilot scale for replacing shrimp (Litopenaeus vannamei) maturation and cooking, analyzing its impact on peeling yield, color, texture and sensory properties. Shrimps subjected to conventional maturation (ice; 2 days) and thermal cooking (100 °C; boiling water, 3 min) were used as controls.PATP treatments at 100-350 MPa improved manual peelability over the control (P ≤ 0.05), maintaining similar peeling yield, color (L*, a*, b*), texture (shear force, shear work) and sensory properties (appearance before and after peeling, flavor, firmness; P 0.05). However, increasing pressure to 600 MPa clearly overprocessed the samples, making it impossible to remove all the meat from the shell and resulting in a softer texture, 4.1% lower peeling yield and worse sensory quality (P ≤ 0.05).PATP ( 350 MPa; 100 °C) could be an alternative to replace conventional maturation and thermal cooking in the production of cooked shrimps, reducing processing time from days to minutes by performing both processes in a single step. © 2022 Society of Chemical Industry.

This work was focused on the application of high pressure processing (HPP) in frozen albacore tuna as a pretreatment before the frozen storage (BFS) or before thawing (BT) to minimize the negative effects of these conventional processes. Two different HPP pretreatments were evaluated (200/6: 200 MPa for 6 min; 600/0: 600 MPa for 0 min) and, after up to 45 days of frozen storage, thawing loss, color, texture, salt-soluble protein content, and lipid oxidation were analyzed once thawed. The application of HPP before thawing or before frozen storage reduced the thawing losses with respect to controls. For example, after 45 days of frozen storage, thawing loss of 600/0 BT and 600/0 BFS samples were 1.0 ± 0.1% and 1.8 ± 0.2%, whereas in the controls it was 5.0 ± 0.4%. After 45 days of storage, HPP BT samples presented lower thawing losses than the HPP BFS ones. Since non-important differences were detected in the rest of the studied parameters between both kinds of treatments, the application of HPP before thawing would be the best option. Regarding the tested HPP pretreatments, although 600/0 decreased thawing loss in a major extent than 200/6, this pretreatment led to sharp changes in color than 200/6 (higher L* and b* values) and texture (higher hardness and chewiness). Therefore, according to the results, the application of 200/6 BT would be a compromise option for reducing thawing loss in albacore with minimal changes on quality.

The First European Symposium on the Evolution of Crocodylomorpha took place during the XVI Annual Meeting of the European Association of Vertebrate Palaeontologists (EAVP) organized by NOVA University of Lisbon (UNL) in Caparica, Portugal. Fourteen lectures and five posters were presented at the symposium in June 26th–July 1st, 2018. This special issue showcases twelve papers based on symposium contributions.

A review of the type material of the crocodylomorph ichnotaxon Crocodylopodus meijidei Fuentes Vidarte and Meijide Calvo, 2001 from the Berriasian of Spain is carried out. The review allows a better characterization of this type ichnotaxon and provides interesting new data on the candidate trackmakers and especially on their locomotion. Three different size classes possibly related to different ontogenetic states or sexual dimorphism of the same small- to medium-sized crocodylomorph trackmaker are distinguished. Morphological differences within the sample such as digital impression lengths might be a consequence of differences in allometric growth, assuming similarities with extant crocodylians. Other differences are a consequence of variation in the morphological quality and mode of preservation across the sample. Some trackway features (intermediate-gauge trackways with high pace angulation, absence of tail, belly or drag marks) indicate the trackmakers, presumed neosuchian crocodylomorphs, were walking in a ‘high-walk’ mode with a semi-erect posture at a moderate speed. The trackmaker may have walked with more erect limb posture and with the center of mass located more anteriorly than occurs in extant species, albeit not as erect as quadrupedal animals such as mammals or other extinct archosaurs including trackmakers of other crocodylomorph ichnotaxa (e.g., Batrachopus). © 2022, by the Society of Vertebrate Paleontology.

Crocodylomorphs were a diverse clade in the Late Jurassic of Portugal, with six taxa reported to date. Here we describe 126 isolated teeth recovered by screen-washing of sediments from Valmitão (Lourinhã, Portugal, late Kimmeridgian–Tithonian), a vertebrate microfossil assemblage in which at least five distinct crocodylomorph taxa are represented. Ten morphotypes are described and attributed to five clades (Lusitanisuchus, Atoposauridae, Goniopholididae, Bernissartiidae and an undetermined mesoeucrocodylian). Four different ecomorphotypes are here proposed according to ecological niches and feeding behaviours: these correspond to a diet based on arthropods and small vertebrates (Lusitanisuchus and Atoposauridae), a generalist diet (Goniopholididae), a durophagous diet (Bernissartiidae) and a carnivorous diet. Lusitanisuchus mitracostatus material from Guimarota is here redescribed to achieve a better illustration and comparison with the new material. This assemblage shares similar ecomorphotypes with other Mesozoic west-central European localities, where a diversity of crocodylomorphs lived together, avoiding direct ecological competition through niche partitioning. The absence of large marine crocodylomorphs, present in other contemporaneous assemblages, is here interpreted as evidence that the Valmitão assemblage was deposited in a freshwater environment, although sample bias cannot be completely ruled out. These affinities are further supported by the presence of lanceolate and leaf-shaped teeth associated with continental clades.

During recent years, knowledge about crocodyliform diversity of the uppermost Cretaceous from Europe has been substantially improved. Palaeontological efforts have also been focused on microvertebrate diversity and its palaeoecological implications. Isolated crocodylomorph teeth are, by far, one of the most frequently recovered elements in microvertebrate samples. In the present paper, morphological features of crocodylomorph teeth collected throughout the complete Maastrichtian series of the southern Pyrenean basin (north-eastern Spain), together with several mandibular remains, are described and analysed. Teeth were grouped in morphotypes and their taxonomic significance is discussed. The results highlight a diverse crocodylomorph assemblage in this area throughout the Maastrichtian. In addition, feeding habits and environmental preferences are inferred for the identified taxa according to dental features, occurrences and taphonomy.

This research is focused on optimizing high-pressure processing (HPP) for decreasing weight loss of albacore steaks (Thunnus alalunga) while retaining as much as possible the quality of fresh fish. After HPP treatments (0.1–500 MPa, 2 min), samples were stored (24 h, 4°C) and then analyzed (weight loss, color, texture, appearance, water holding capacity, salt-soluble protein content, and lipid oxidation). Weight loss increased from 50 to 150 MPa, without other substantial modification. Above 200 MPa, HPP treatment caused a progressive weight loss reduction. 200 MPa decreased weight loss by 41.6% with respect to 150 MPa, without noticeable changes in color, texture, appearance, or lipid oxidation. 250 MPa decreased weight loss by 50.1% compared to the controls but produced minor changes in color. 500 MPa provoked the maximum reduction of weight loss with respect to the controls (59%), although it caused marked differences in all quality parameters, which would affect consumer acceptance.

Throughout the evolutionary history of Avialae, several members of this clade have evolved into giant forms, in different time periods and ecological contexts. In Europe, the first birds that show ...

The South-Pyrenean Basin (northeastern Spain) has yielded a rich and diverse record of Upper Cretaceous (uppermost Campanian−uppermost Maastrichtian) vertebrate fossils, including the remains of some of the last European dinosaurs prior to the Cretaceous-Paleogene (K-Pg) extinction event. In this work, we update and characterize the vertebrate fossil record of the Arén Sandstone and Tremp formations in the Western Tremp Syncline, which is located in the Aragonese area of the Southern Pyrenees. The transitional and continental successions of these sedimentary units are dated to the late Maastrichtian, and exploration of their outcrops has led to the discovery of numerous fossil remains (bones, eggshells, and tracks) of dinosaurs, including hadrosauroids, sauropods, and theropods, along with other tetrapods such as crocodylomorphs, testudines, pterosaurs, squamates, and amphibians. In particular, this fossil record contains some of the youngest lambeosaurine hadrosaurids (Arenysaurus and Blasisaurus) and Mesozoic crocodylomorphs (Arenysuchus and Agaresuchus subjuniperus) in Europe, complementing the lower Maastrichtian fossil sites of the Eastern Tremp Syncline. In addition, faunal comparison with the fossil record of Hațeg island reveals the great change in the dinosaur assemblages resulting from the arrival of lambeosaurine hadrosaurids on the Ibero-Armorican island, whereas those on Haţeg remained stable. In the light of its paleontological richness, its stratigraphic continuity, and its calibration within the last few hundred thousand years of the Cretaceous, the Western Tremp Syncline is one of the best places in Europe to study the latest vertebrate assemblages of the European Archipelago before the end-Cretaceous mass extinction.

The recovery of valuable compounds from food wastes and by-products kills two birds with one stone and addresses both the use of by-products and societal health care. Traditional extraction methods include usually high-temperature treatment (more than 100°C) with the subsequent risk of thermal denaturation or transformation of the target molecules. Moreover, these techniques are very time-consuming and require relatively large quantities of solvents. On the other hand, the use of environment-friendly technologies has led researchers and the food industry to develop new alternative processes that can extract valuable compounds from different sources and food wastes of different origins. This chapter describes the potential use of emerging technologies such as ultrasound-assisted extraction, laser ablation, pulsed electric fields, high-voltage electrical discharge, membrane-assisted extraction, and solvent-induced complexation. The latest methodologies comply with the concepts of green chemistry and sustainability.

A new plesiosaur partial skeleton, comprising most of the trunk and including axial, limb, and girdle bones, was collected in the lower Sinemurian (Coimbra Formation) of Praia da Concha, near São Pedro de Moel in central west Portugal. The specimen represents a new genus and species, Plesiopharos moelensis gen. et sp. nov. Phylogenetic analysis places this taxon at the base of Plesiosauroidea. Its position is based on this exclusive combination of characters: Presence of a straight preaxial margin of the radius; transverse processes of mid-dorsal vertebrae horizontally oriented; ilium with sub-circular cross section of the shaft and subequal anteroposterior expansion of the dorsal blade; straight proximal end of the humerus; and ventral surface of the humerus with an anteroposteriorly long shallow groove between the epipodial facets. In addition, the new taxon has the following autapomorphies: Iliac blade with less expanded, rounded and convex anterior flank; highly developed ischial facet of the ilium; apex of the neural spine of the first pectoral vertebra inclined posterodorsally with a small rounded tip. This taxon represents the most complete and the oldest plesiosaur species in the Iberian Peninsula. It is also the most complete, best preserved, and oldest marine vertebrate in the region and testifies to the incursion of marine reptiles in the newly formed proto-Atlantic sea, prior to the Atlantic Ocean floor spreading in the Early Cretaceous. publishersversion published

BACKGROUND This research evaluates the application of high-pressure processing (HPP) before freezing to reduce weight loss related to thawing and cooking of frozen albacore steaks (Thunnus alalunga) with a minimal impact on fish quality (color, texture, soluble protein, lipid oxidation). Albacore steaks were HPP pretreated (200, 250, and 300 MPa for 0, 2, 4 and 6 min), frozen (-20 °C, 5 m s-1 ), thawed (4 °C; 24 h), and then analyzed. RESULTS At lower pressures (200 MPa) there was a clear effect of pressurization time on most of the fish quality parameters tested (thawing loss, L* value, b* value, ΔE, adhesiveness, springiness, salt-soluble protein content), whereas at higher pressures (300 MPa) similar changes took place independently of the pressurization time. High-pressure processing had no impact on lipid oxidation . A pressure of 200 MPa applied for 6 min decreased thawing, cooking, and total weight losses (53.7%, 55.4%, and 51.0% lower than the frozen control, respectively) although it led to noticeable changes in color. A pressure of 200 MPa applied for 2 min decreased thawing, cooking, and total weight losses by 23.2%, 44.0% and 33.7% with respect to the frozen control, respectively, with only minor changes in color. CONCLUSION High-pressure processing pretreatment could be a promising tool for reducing weight loss in frozen fish when HPP conditions are properly selected. A pressure of 200 MPa applied for 2 min could be a good compromise treatment, cutting thawing and cooking losses in albacore, and reducing HPP-mediated color alterations and the related possible consumer rejection. © 2020 Society of Chemical Industry.

Eduardo Puertolas Pascual is the recipient of a postdoctoral grant (SFRH/BPD/116759/2016) funded by the Fundacao para a Ciencia e a Tecnologia (FCT-MCTES).

The increasing prevalence of food allergies is a health problem of global concern, but also an important opportunity for the food industry to develop novel food products with innovative functionalities. Accordingly, and parallelly to health research advances, food scientific community has been working in innovations for achieving attenuation of hypersensitivity responses in allergenic individuals using, among other strategies, food processing technologies. Processing techniques involving intense heat treatment have been usually studied for this purpose but may be accompanied by significant changes in food quality attributes. Therefore, current nonthermal technologies, including high-pressure processing (HPP) presents a fantastic opportunity for achieving hypoallergenicity of selected foods. This chapter tries to reveal and summarize the current knowledge and recent findings on the possibility of using high-pressure processing for the reduction or elimination of allergenic proteins in foods from a practical point of view. To provide a comprehensive overview, not only specific successful cases with main allergens (milk, egg, peanuts, soy, nuts, and seafood) are addressed, but also other food allergens, negative or nonexistent results and important considerations to take into account are presented, relying on the near future potential applications of this technology.

Innovation represents an extremely important strategy for food companies to remain competitive and to meet consumer demands. Consumers judge food quality mainly based on its sensory and nutritional characteristics and, in conjunction with shelf life (and safety), these now determine an individual’s preference for specific products. High-pressure processing (HPP) is one of the nonthermal processing technologies that is seeing an increased presence in the food sector because it helps preserve these expected sensory and nutritional qualities while ensuring a proper shelf life and microbial safety. Although HPP has been primarily used in the juice and meat sectors, during the last decades many applications in other sectors have emerged, including the seafood sector. This chapter focus on the application of HPP in seafood products, summarizing the main effects of this emerging technology on seafood components and quality parameters. A description of the most important industrialized and nonindustrialized (but forthcoming) applications is also provided.

The aim of this work was to study the effect of different air blast freezing conditions (temperature: −20 °C, air velocity: 1 m/s; −20 °C, 5 m/s; −50 °C, 1 m/s; −50 °C, 5 m/s) on the quality of high pressure processing (HPP) pretreated (200 MPa, 6 min) albacore steaks. After 2 and 9 months of frozen storage, HPP and control samples were thawed and analyzed (thawing loss, cooking loss, total weight loss, color, texture profile, salt-soluble protein content and lipid oxidation). The HPP pretreatment had more impact on the albacore quality than lowering the freezing temperature or increasing the air velocity. For instance, after 9 months of frozen storage, the HPP pretreated samples before freezing under the slowest (−20 °C and 1 m/s) and the fastest (−50 °C and 5 m/s) freezing conditions presented similar thawing loss reductions (37 and 40%, respectively) with respect to their corresponding controls. Considering the conditions and parameters tested, HPP pretreatment (200 MPa, 6 min) followed by a freezing at −50 °C (at 1 or 5 m/s) would achieve the best results in albacore after up to 9 months of frozen storage.

There has been a growing interest to reuse food waste and by-products from different processing steps, not only to ensure the environmental sustainability but also to improve the economic performance of the processes. One way of recovery that has raised more interest is the extraction of valuable compounds, which can be used as ingredients in food and pharmaceutical industries due to their technological function, nutritional properties, or their beneficial effects on human or animal health. In many cases, conventional solvent extraction cannot be economically feasible or involves the use of toxic solvents, hindering their subsequent management, or high temperatures, with consequent degradation of thermolabile compounds. Therefore, new pretreatment technologies that can partially or completely replace conventional methods, thus reducing the solvent consumption, temperature and/or the extraction time, can be a useful tool to get more efficient and sustainable processes. The use of electrotechnologies, especially pulsed electric fields and high voltage electrical discharges, may be a promising tool to achieve the above mentioned purposes, thus improving extraction processes in the upgrading of by-products. In this review, the main results published are summarized, emphasizing their potential applications and studying their energy and economic cost, a key aspect to assess its industrial viability.

Oil recovery from oilseeds and fruits is one of the food processes where efficiency is the key to ensure profitability. Wastes and by-products generated during oil production process are, on the other hand, a great source of high-added value compounds that could be recovered in turn at a later stage. In many cases, physical extraction processes present efficiency problems or just not profitable, requiring a chemical solvent extraction that could be toxic and difficult to manage from an environmental point of view. Furthermore, the use of high temperatures to improve and/or accelerate the processes (with consequent degradation of thermolabile compounds) is usually required. Therefore, the application of new pre-treatment technologies to replace partially or completely the conventional methods, and to achieve the processes more efficiently and sustainably is of great importance. Electrotechnologies, especially pulsed electric fields and high voltage electrical discharges are some of the most promising techniques. In this review, the main published results are summarized, emphasizing their potential applications and studying their energy and economic cost, a key aspect to assess their industrial viability.

The aim of this work was to study the application of high pressure processing (HPP) before freezing for maintaining as much as possible the fresh characteristics of albacore steaks after long-term storage. HPP treatments were applied at 200 MPa for 0–6 min. Then, samples were immediately frozen (−20 °C) and stored (−20 °C) for up to 12 months. Once thawed (4 °C; 24 h), weight losses, color, texture, lipid oxidation (TBARS) and salt-soluble protein content were analyzed. After 12 months of frozen storage, 200 MPa for 6 min minimized thawing loss inherent to freezing and frozen storage and decreased TBARS (53.9%) with respect to the control. However, it resulted in changes in color (higher L*, b* and ΔE values) and texture (higher adhesiveness and springiness) and decreased the salt-soluble protein content with respect to non-pretreated samples. Nevertheless, after cooking, there were no differences in color and texture between HPP pretreated fish and the controls.

Although the European dinosaur succession during the latest Cretaceous and its relationship with the Cretaceous-Paleogene (K-Pg) mass extinction has been the focus of recent work, other continental vertebrates, such as crocodylomorphs, have received less attention. The European continental record of crocodylomorphs in general, and of eusuchians in particular, is relatively dense through the Maastrichtian until the K-Pg boundary. Traditionally it has been argued that continental crocodylomorphs were minimally impacted by the K-Pg extinction, but they were substantially affected in Europe with the disappearance of endemic eusuchians such as Hylaeochampsidae, Allodaposuchus and their close relatives, and non-eusuchians such as Doratodon or Theriosuchus. Despite extensive sampling in Danian continental deposits, only scarce fragmentary crocodylomorph remains have been cited. It is not until the late Paleocene and Eocene that a recovery in continental crocodylomorphs is observed. The presence of taxa such as planocraniids, the alligatoroids Diplocynodon and Hassiacosuchus, and stem crocodyloids during this period provide the first reliable continental records of Crocodylia in Europe and is best explained by post-extinction immigration from Asia or North America. By contrast, marine forms such as Thoracosaurus are found on both sides of the K-Pg boundary in Europe. The adaptation of these marine animals to different environments, from shallow seas to more transitional or fluvial environments, could be the key to their success and survival across the K-Pg boundary, as seen in other marine crocodylomorph clades such as Dyrosauridae.

The transitional-continental facies of the Tremp Formation within the South-Pyrenean Central Unit (Spain) contain one of the best continental vertebrate records of the Upper Cretaceous in Europe. This Pyrenean area is therefore an exceptional place to study the extinction of continental vertebrates across the Cretaceous/Paleogene (K/Pg) boundary, being one of the few places in Europe that has a relatively continuous record ranging from the upper Campanian to lower Eocene. The Serraduy area, located on the northwest flank of the Tremp syncline, has seen the discovery of abundant vertebrate remains in recent years, highlights being the presence of hadrosaurid dinosaurs and eusuchian crocodylomorphs. Nevertheless, although these deposits have been provisionally assigned a Maastrichtian age, they have not previously been dated with absolute or relative methods. This paper presents a detailed stratigraphic, magnetostratigraphic and biostratigraphic study for the first time in this area, making it possible to assign most vertebrate sites from the Serraduy area a late Maastrichtian age, specifically within polarity chron C29r. These results confirm that the vertebrate sites from Serraduy are among the most modern of the Upper Cretaceous in Europe, being very close to the K/Pg boundary., Spanish Ministry of Economy and Competitiveness (grant numbers CGL2014-53548-P, CGL2015-64422-P and CGL2017-85038-P), cofinanced by the European Regional Development Fund; and by the Department of Education and Science of the Aragonese Government (grant numbers DGA groups H54 and E05), cofinanced by the European Social Fund (ESF). The paleomagnetic study was possible thanks to the complementary grants (beneficiaries of FPU, grant number CGL2010-16447/BTE: Brief Stays and Temporary Transfers, year 2015) supported by the Spanish Ministry of Culture, Education and Sports; and the Laboratory of paleomagnetism of the University of Burgos (Spain). Eduardo Puértolas Pascual is the recipient of a postdoctoral grant (SFRH/BPD/116759/2016) funded by the Fundação para a Ciência e Tecnologia (FCT-MCTES).

The impact of the use of pulsed electric field (PEF) technology on Arroniz olive oil production in terms of extraction yield and chemical and sensory quality has been studied at pilot scale in an industrial oil mill. The application of a PEF treatment (2 kV/cm; 11.25 kJ/kg) to the olive paste significantly increased the extraction yield by 13.3%, with respect to a control. Furthermore, olive oil obtained by PEF showed total phenolic content, total phytosterols and total tocopherols significantly higher than control (11.5%, 9.9% and 15.0%, respectively). The use of PEF had no negative effects on general chemical and sensory characteristics of the olive oil, maintaining the highest quality according to EU legal standards (EVOO; extra virgin olive oil). Therefore, PEF could be an appropriate technology to improve olive oil yield and produce EVOO enriched in human-health-related compounds, such as polyphenols, phytosterols and tocopherols.

The Upper Cretaceous outcrops of the Pyrenees yield one of the most extensive and continuous records of paleoological remains anywhere in the world. Most of eggs and eggshells have been referred to...

This paper describes the skull of the eusuchian Allodaposuchus subjuniperus sp. nov. This new skull was recovered between the villages of Beranuy and Serraduy del Pon (Huesca, Spain). Stratigraphic...

En las ultimas decadas, la industria alimentaria ha experimentado un importante avance tecnologico que se refleja en el desarrollo de nuevas tecnicas y procesos de elaboracion. Especialmente han cobrado particular importancia aquellas tecnologias que permiten obtener alimentos seguros, alterando minimamente sus caracteristicas sensoriales y/o disminuyendo los costes de produccion. Una de las tecnologias emergentes mas prometedoras, que pretende conseguir estos objetivos, son los pulsos electricos de alto voltaje (PEAV). El objetivo de este trabajo es revisar la viabilidad de la aplicacion industrial de los PEAV para la pasteurizacion de alimentos liquidos desde un enfoque tecnico, ambiental, economico y comercial. Se recogen los principales avances y datos publicados al respecto, asi como los desafios existentes para la implantacion de esta tecnologia en la industria alimentaria.

International audience; Food industry is generating annually huge quantities of by-products and waste, which are generally considered as problem, as their disposal is associated with environmental and health related issues. During the last decade, numerous research groups and industries have been interested in valorizing these by-products by extracting valuable compounds and incorporating them generally in food and/or cosmetic products, which enhances the profitability of the process. Conventional extraction methods (i.e., maceration, thermal extraction) are exten- sively used for such purposes and showed high yields in many cases. However, the need to replace toxic organic solvents, shortening the extraction time, and reducing the energy consumption has incited the researchers to develop and evaluate alternative methods (i.e., electrotechnologies, high pressure processing, ultrasound- and microwave-assisted extractions), which are more environmental friendly and cost effective. Among electrotechnologies, pulsed electric fields (PEF) technology has been widely evaluated for the extraction of high-added value compounds from waste and by-products, showing promising results, com- pared to conventional methods. This chapter describes the features of PEF as well as its use as sustainable and green recovery technology of valuable compounds from food by-products.

This study investigated the effect of maceration time (0–6 h) and maceration temperature (4–20 °C) on the anthocyanin content of Cabernet Sauvignon rose wines obtained from grapes treated with pulsed electric fields (PEF) (5 kV/cm; 50 pulses). A response surface model based on a modified central composite experimental design was used to describe the influence of these factors. Wines obtained from PEF-treated grapes, consistently presented higher anthocyanin content than control wines after 2 months of storage in bottles. At a fixed maceration time of 2 h, the PEF treatment allowed the necessary reduction of the maceration temperature to obtain an anthocyanin level of 50 mg/L from 20 to 4 °C. This temperature reduction could decrease the oxidation of phenols and the loss of aromatic compounds, thus increasing the quality of rose wine. According to our results, PEF is a promising technique to improve the anthocyanin extraction and to reduce the maceration time for the production of rose wines at cold temperatures.

Changes in the principal phenolic compounds during the maceration-fermentation process of Garnacha, Merlot and Syrah grapes cultivated in Aragón region (northeast of Spain) have been investigated. While Garnacha is a traditional grape variety cultivated in this region, Merlot and Syrah have been introduced recently. During fermentation, Syrah showed the highest concentration in anthocyanins, flavan-3-ols and flavonols (802.7 ± 0.5 mg/L, 74.7 ± 2.4 mg/L and 37.1 ± 1.5 mg/L at the end of fermentation, respectively). Unexpectedly, Garnacha, a variety with lower phenolic content, showed the highest amount of hydroxycinnamic acids (83.1 ± 5.6 mg/L at the end of fermentation). The overall results also indicated that the evolution during maceration-fermentation process of the different phenolic compounds and their concentrations were influenced by the varietal factor.

A static parallel electrode treatment chamber with tempered electrodes has been designed to obtain kinetics data on microbial inactivation by pulsed electric fields (PEF) at different temperatures at quasi-isothermal conditions. Distribution of the electric field strength and temperature within the treatment zone was estimated by a finite element method. A good agreement was observed between the temperatures estimated by numerical simulation and temperatures measured by a thermocouple in the treatment zone before and after the PEF treatments (values of RMSE below 3%). Influence of the treatment temperature on PEF inactivation (30 kV/cm) of Salmonella typhimurium was investigated at temperatures between 4 and 50 °C in media of pH 3.5 and 7.0. Treatment temperature had an important effect on microbial inactivation for both values of pH. At pH 3.5 the inactivation of S. typhimurium was irrelevant at 4 °C but about 1.5, 2.9, 4.0 and 5.0 Log10 reductions were obtained after 30 pulses (90 μs) at 15, 27, 38 and 50 °C, respectively. At pH 7.0, around two Log10 cycles of inactivation were observed after 50 pulses (150 μs) at 4 °C. At temperatures in the range between 15 and 50 °C the treatment temperature practically did not influence PEF resistance of S. typhimurium. A model based on the Weibull distribution adequately described kinetics of inactivation of S. typhimurium at different temperatures. The treatment chamber designed in the investigation could be useful to obtain kinetics data on PEF destruction of microorganisms or other components of interest at a uniform distribution of electric field strength and homogeneous and quasi-isothermal conditions in a wide range of temperatures.

A study of the effect of pulsed electric fields (PEF) on the inactivation of Listeria monocytogenes STCC 5672 and Staphylococcus aureus STCC 4459 in McIlvaine buffer covering a range from pH 3.5 to 7.0 was conducted. Mathematical models based on the Weibull distribution were developed to describe the influence of the electric field strength, treatment time and pH of the treatment medium on the lethality of both Gram positive pathogenic bacteria after PEF treatments. Both microorganisms were more sensitive to PEF in media of low pH, although the influence of the pH on the PEF resistance was more significant in S. aureus . In the best cases scenario, the highest inactivation levels achieved were 3.3 and 6.1 log 10 cycles for L. monocytogenes and S. aureus respectively in pH 3.5 after 500 μs of 35 kV/cm. Based on these results and those observed in literature, L. monocytogenes STCC 5672 at any pH investigated has been shown as one of the most PEF resistant microorganism. Therefore, this microorganism should be considered as a possible target microorganism to define process criterion for PEF pasteurization.

The feasibility of processing red grapes by pulsed electric fields (PEF) at pilot-plant scale to improve the extraction of anthocyanins and phenols during the maceration-fermentation step of the winemaking process has been investigated. With this general purpose a colinear continuous treatment chamber was developed. The influence of field strength (2, 5 and 7 kV/cm) and grape variety (Cabernet Sauvignon, Syrah and Merlot) in the extraction kinetics was studied. Extraction curves were described by an exponential equation that permits to estimate the extraction rate ( k ) and the maximum extraction yield ( Y max ). An increment of the electric field from 2 to 7 kV/cm increased the extraction rate of anthocyanins and total phenols for the three varieties investigated. The increment of Y max due to the application of PEF was more remarkable in Cabernet Sauvignon than in Merlot and Syrah. The continuous PEF system presented in this work constitutes an important step for the application of PEF technology at commercial scale.

Pulsed electric fields (PEF) technology is one of the novel food processing techniques upon which research effort is currently focused. In the last few years, various studies have examined the potential applications of this technology in the winemaking industry: the improvement of the phenolic extraction during the maceration process and the inactivation of spoilage microorganisms. The aim of this review is to look at the state of the art and to note the most important challenges of the future application of PEF in winemaking.

A study of the effect of pulsed electric fields (PEF) on the kinetics of inactivation and the occurrence of cell damage in Escherichia coli O157:H7 and Salmonella Typhimurium 878 treated in McIlvaine buffer covering a range from pH 3.5 to 7.0 was conducted. Mathematical equations based on the Weibull distribution were developed to describe the influence of the electric field strength, treatment time and pH of the treatment medium on the lethality and generation of cell damage of both Gram negative pathogenic bacteria after the application of PEF treatments. E. coli O157:H7 was more PEF resistant than Salmonella Typhimurium at all pH investigated. PEF resistance of E. coli was influenced by the pH but the pH hardly affected the PEF resistance of Salmonella Typhimurium 878. After 150 μs at 35 kV/cm, 1 and 5 log10 cycles of inactivation of E. coli O157:H7 were observed in the range of pH 3.5–4.5 and 5.5–6.5, respectively. Cell damage increased with the field strength and treatment time. A maximum cell damage level of 4.2 and 2.7 log10 cycles for E. coli O157:H7 and Salmonella Typhimurium was observed respectively after a treatment of 30 kV/cm at pH 3.5. PEF induced cell damage was not detected at pH higher than 5.0 for both microorganisms. The developed equations can be applied to design combining processes which can increase the lethality of PEF or to reduce the intensity of PEF treatments to achieve a determine level of microbial inactivation. Industrial relevance This study demonstrates that when the influence of several factors on the microbial behavior is investigated, the development of mathematical models is a very useful tool to evaluate the influence of each parameter and their interactions. In this study, it has been mathematically described for first time the influence of the pH of the treatment medium and the occurrence of sublethal injury in a wide range of electric field strengths and treatment times in two Gram negative pathogenic bacteria, Escherichia coli O157:H7 and Salmonella Typhimurium 878. These models would also be of interest for engineering design, evaluation and optimization of PEF process as a new technique for food preservation.

The influence of the application of a continuous pulsed electric fields treatment (PEF treatment) to grape pomace on the evolution of colour and phenolic content of Cabernet Sauvignon red wines has been investigated. Wine from grape treated by PEF presented at the end of alcoholic fermentation higher colour intensity (CI), total polyphenol index (TPI) and total anthocyanic content (TAC) than control wine. This effect was observed even although maceration time for PEF wine was 48 h shorter than for control. Differences remained during malolactic fermentation and maturation. After 4 months of aging in bottle, CI, TPI and TAC of PEF wine were 38%, 22% and 11% higher respectively than the control. HPLC phenolic profiles of wines were qualitatively similar, without detecting a selective effect on any phenol. No significant differences in sensory attributes between wines were detected. Results indicate that PEF is a promising technology in red winemaking for reducing the maceration time and increasing colour and phenolic extraction.

In this study, the lethal effectiveness of pulsed electric fields (PEF) on the inactivation of Salmonella enterica subs. enterica ser. Typhimurium and Staphylococcus aureus in liquid whole egg (LWE) has been investigated. Maximum inactivation levels of 4 and 3 Log 10 cycles of the population of Salmonella Typhimurium and S. aureus were achieved with treatments of 45 kV/cm, 30 μs and 419 kJ/kg, and 40 kV/cm for 15 μs and 166 kJ/kg, respectively. The non-linear kinetics of inactivation observed for both microorganisms at all the investigated electric field strengths were described by mathematical equations based on the Weibull distribution. The developed equations enabled to compare the microbial resistance to PEF and to establish the most suitable treatment conditions to achieve a determined level of microbial inactivation. PEF treatments varying from 30 kV/cm, 67 µs and 393 kJ/kg to 45 kV/cm, 19 µs and 285 kJ/kg allow to reduce 3 Log 10 cycles the population of the microorganism of concern in PEF food processing of LWE, Salmonella Typhimurium. Industrial relevance The data presented in this investigation in terms of electric field strength, specific energy and treatment time result of relevance to evaluate the possibilities of PEF technology to pasteurize LWE with this technology. The models developed in this study can be applied to engineering design, and for the evaluation and optimization of the PEF technology as a new technique to obtain Salmonella free LWE. Based on our results it is not recommended to apply treatments of energy levels higher than 250 kJ/kg, since PEF lethality hardly increased but markedly augmented the energetic costs. For these energy values, PEF technology by itself is not sufficient (3 Log10 cycles in the best case scenario) to assure the safe security of LWE. Therefore, intelligent combinations of PEF with other preservation technologies have to be developed in order to use pulsed electric fields as an alternative to heat pasteurization of LWE.

The influence of a pulsed electric field (PEF) treatment of grape berries at pilot-plant scale on the evolution of the chromatic and phenolic characteristics of Cabernet Sauvignon red wines during aging in American oak barrels and subsequent storage in bottle has been studied. Results obtained in this investigation confirm that the better chromatic characteristics and higher phenolic content obtained due to the PEF treatment after the fermentation process remain or even increase during aging in oxidative conditions in American oak barrels and their subsequent storage in bottle. No sensory differences in color and bouquet were detected after 8 months of aging in bottle by triangle tests. According to the results, PEF is a promising enological technology to obtain wines with the high phenolic content necessary for the production of high quality oak aged red wines.