Research advances and application of pulsed electric field on proteins and peptides in food

From waste to value: Integrating legume byproducts into sustainable industrialization

As the global demand for sustainable food sources grows, the effective utilization of agro-industrial byproducts has become increasingly essential. Among these, legume byproducts, which are often discarded as waste, hold substantial nutritional and functional properties that can significantly contribute to advancing circular economy goals within the food industry. Current research has unveiled the potential of these byproducts to enhance both environmental sustainability and economic efficiency. Rich in proteins, dietary fibers, and bioactive compounds, legume byproducts can serve as valuable resources in developing functional food ingredients. This review explores the nutritional profiles of various legume byproducts and highlights innovative processes and technologies involved in their valorization, such as fermentation, enzymatic treatments, and novel extraction techniques. Furthermore, it explores the impact of food formulations in optimizing the functional properties of legume byproduct-based ingredients, considering their impact on texture, stability, and sensory attributes. Consumer perceptions of sustainable products derived from these ingredients are also examined, emphasizing their potential to reshape modern dietary preferences toward more sustainable choices. However, despite the promising potential of these byproducts, several challenges remain to be solved, including the antinutrients factor, market limitations, limited consumer awareness, and complexities in scaling up production. In addition, it is essential to integrate circular economy principles and conduct life-cycle assessments throughout the value chain to ensure the sustainable use of legume byproducts. Addressing these challenges is critical to enhancing the valorization of legume byproducts and promoting a more comprehensive approach to food system sustainability.

Obtaining bioactive peptides by enhancing enzymatic hydrolysis of salmon by-product proteins through pulsed electric fields (PEF)

Pulsed Electric Fields (PEF) exhibit significant potential to modify proteins and enzymes, enhancing their enzymatic activity and increasing bioactive peptide production. This work aimed to enhance the obtention of bioactive peptides using PEF as a pre-treatment for enzymatic hydrolysis of salmon by-product proteins. Results show that PEF treatments at 15 and 20 kV/cm improved flavourzyme (FV) enzymatic activity by altering the protein's tertiary structure, decreasing its surface hydrophobicity and intrinsic fluorescence. PEF improved the hydrolysis process, especially when both FV and salmon protein were subjected to PEF, increasing the hydrolysis degree and peptide yield from 9.6 % up to 16.6 % and 10.6 % up to 18.7 %, respectively. PEF-assisted hydrolysis modified molecular weight distribution of the peptides obtained, increasing the amount of 3 and 5 kDa peptides. Optimal antioxidant and anti-ACE activities were achieved by applying PEF at FV and SPI at 50 Hz and 15 kV/cm. These findings suggest that PEF is a promising technology for producing bioactive peptides by increasing enzyme activity and improving the obtained peptide yield.

Applications of sustainable proteins in food and feed, and perspectives on health and circular bioeconomy

There has been a recent trend towards the use of "sustainable proteins" in attempts to meet the global challenge for healthier and more environmentally friendly food and feed systems. These renewable-source-derived proteins are novel sources of conventional proteins. The extraction methodologies for sustainable proteins, having been developed, are quite efficient in yielding high-quality proteins for such applications. Sustainable proteins have the potential to enhance nutritional profiles, enable advanced food and feed production techniques, and contribute to functional food product development. Furthermore, cross-linking and encapsulation strategies ensure stability and controlled delivery of proteins and derivatives from the green source to healthy pathways. By integrating sustainability assessments and life cycle analysis, sustainable proteins align with global biodiversity and climate goals, fostering a circular bioeconomy; this review explores their potential, focusing on extraction methodologies, functional applications, health benefits, and the role of policy frameworks in advancing resource-efficient and eco-friendly food and feed systems.

Production of bioactive peptides by high-voltage pulsed electric field: Protein extraction, mechanism, research status and collaborative application

Bioactive peptides exhibit a variety of potential applications in the fields of medicine, food and cosmetics. However, studies have shown that the traditional preparation is characterized by low efficiency, substantial pollution, limited activities and poor purity, which constrains their further application. High-voltage pulsed electric field (HPEF) technology, as a physical non-thermal processing method, shows unique advantages in bioactive peptide preparation. Through comprehensive analysis, this paper reveals the main principle of HPEF technology, the extraction of proteins (break up cellular tissue), the structural changes of proteins, enzymes and bioactive peptides after treatment, the improvement of bioactive peptides' functional properties and the potential in promoting bioactive peptides' large-scale production. Besides, this paper introduces the application of other non-thermal processing technologies, artificial intelligence and nanotechnology, providing new ways of thinking for the efficient preparation and application of bioactive peptides and establishes a theoretical foundation for the application and promotion of HPEF technology.

Recent advances in plant protein-based sustainable edible film and coatings for applications in the food-pharma industry - Opportunities and challenges: A review

Plant protein-based edible film and coatings have emerged as eco-friendly alternatives to synthetic packaging, offering biodegradable, non-toxic solutions. Their biocompatibility and film-forming properties make them suitable for direct application on food products, reducing reliance on non-degradable plastics and lowering environmental pollution. Despite their promising advantages, challenges remain in optimizing mechanical properties, production scalability, and consumer acceptance. This review explores various plant protein sources, latest developments in film-forming techniques, and approaches to address current challenges in developing protein-based film and coatings, highlighting their potential applications in food-pharma industries. Plant-based protein films and coatings have good gas barriers and mechanical qualities. Using plasticizers and post treatments improved physical and mechanical properties of protein-based film and coatings. Moreover, plant protein-based films (PBFs) with active components can slow microbial growth and lipid oxidation. Overall, plant protein-based edible films and coatings hold promise for improving food quality and safety by incorporating bioactive compounds and enhancing barrier properties. However, gaps remain in optimizing their physio-mechanical characteristics, scaling up production, and exploring novel protein sources for diverse applications in food and pharmaceuticals.

Progress in Preparation Technology and Functional Research On Marine Bioactive Peptides

Marine bioactive peptides are a class of peptides derived from marine organisms that can optimize the body's metabolic environment and benefit the body's health. These peptides have attracted increasing amounts of attention due to their wide range of health-promoting effects. Additionally, they have the potential to ameliorate diseases such as hypertension, diabetes, influenza viruses, and inflammation and can be used as functional foods or nutritional supplements for the purpose of treating or alleviating diseases. This paper reviews the recent research progress on marine bioactive peptides, focusing on their production technologies and functions in biomaterials and drug development.

Protein hydrogel formation from chicken processing By-Products: Exploring applications in food

Chicken processing by-products, such as meat left over on bones, skin, frames and connective tissues, are great sources of functional proteins that offer significant potential for value-added applications, contributing to both waste reduction and environmental sustainability. By transforming the recovered proteins from by-products into hydrogels, new materials can be developed for use in various industries, including food. However, understanding the chemical composition of these by-products and optimizing hydrogel production techniques are critical to producing hydrogels with desirable properties. This review examines the latest techniques for isolating proteins from chicken by-products and transforming them into functional hydrogels. It highlights methods of hydrogel preparation, crosslinking, and characterization, with a focus on their conformational properties and applications in food systems. The review also addresses the current scope of health benefits and future potential of these hydrogels in enhancing food product quality. Advances in protein extraction and hydrogel formation show that these hydrogels can retain water, improve gelation, and maintain stability, making them ideal for food products. Specifically, they can be used as edible coatings in fried foods to reduce fat uptake and limit the formation of harmful compounds. Chicken protein-based hydrogels hold great potential for future food processing applications, promoting sustainability and consumer well-being.

Bioactive peptides with potential anticancer properties from various food protein sources: status of recent research, production technologies, and developments

Recently, bioactive peptides, from natural resources, have attracted remarkable attention as nutraceutical treasures and the health benefits of their consumption have extensively been studied. Therapies based on bioactive peptides have been recognized as an innovative and promising alternative method for dangerous diseases such as cancer. Indeed, there has been enormous interest in nutraceuticals and bioactive-based chemopreventive molecules as a potential opportunity to manage chronic diseases, including cancer at different stages, rather than the traditionally used therapies. The relative safety and efficacy of these peptides in targeting only the tumor cells without affecting the normal cells make them attractive alternatives to existing pharmaceuticals for the treatment, management, and prevention of cancer, being able to act as potential physiological modulators of metabolism during their intestinal digestion. Novel bioactive peptides derived from food sources can be beneficial as anticancer nutraceuticals and provide a basis for the pharmaceutical development of food-derived bioactive peptides. Bioactive peptides can be generated through different protein hydrolysis methods and purified using advanced chromatographic techniques. Moreover, establishing bioactive peptides' efficacy and mechanism of action can provide alternative methods for cancer prevention and management. Most of the research on anticancer peptides is carried out on cell lines with very limited research being investigated in animal models or human clinical models. In this context, this review article comprehensively discusses anticancer peptides': production, isolation, therapeutic strategies, mechanism of action, and application in cancer therapy.

Exploring the significance of emerging blue food processing technologies for sustainable development

Blue food processing applies to the production and processing of fish, algae, and other aquatic organisms for human consumption. As the global population grows and consumer demand for protein-rich foods increases, there is increased interest in exploring a wide range of innovative approaches for processing blue foods in ways that improve the efficiency, sustainability, and nutritional quality of these products and reduce the environmental impact of their production. Existing approaches to process blue foods including fishing and aquaculture for production and manual processing at landing are not sufficiently scalable, efficient, or environmentally sustainable for today's global needs. Therefore, many new technologies are being developed and implemented to address these challenges. These technologies include advanced processing technologies such as high-pressure processing, freeze drying, and ultrasound-assisted extraction. New ingredients and additives that can enhance the nutritional and sensory qualities of blue food products, such as seaweed or algae-based antioxidants. Leading edge processing methods are increasing yields, speeding up production while enhancing product quality. The foundation is being established for the large-scale production of diverse, sustainable, nutritious blue food products. These foods will match the taste and appeal of traditional foods, but with quicker, more equitable production and broader economic, social, and environmental benefits, ensuring a consistent supply for the future. Evolution of blue food processing methods and a comparative analysis have been discussed in this review article.

Optimization of pulsed electric fields-assisted thawing process conditions and its effect on the quality of Zhijiang duck meat

Freezing storage is a common preservation method for industrialized duck meat. However, both the frozen storage and thawing processes of meat can affect meat quality. Therefore, appropriate thawing methods are crucial for maintaining good meat quality. In this study, a pulsed electric field (PEF) was used for thawing zhijiang duck meat and the freshed duck meats were used as control. Optimization of the PEF-assisted thawing process and its effect on the quality of zhijiang duck meat were analyzed. Our data showed that the shear force in the 2 kV/cm PEF-assisted thawing group was the lowest in PEF-assisted thawing groups. The color of zhijiang duck meat in the 2 kV/cm PEF-assisted thawing group was optimal. The 2 kV/cm PEF-assisted thawing could improve the texture characteristics of zhijiang duck meat and enhance water holding capacity of zhijiang duck meat. PEF-assisted thawing could better maintain the microstructure of zhijiang duck meat. Our data showed that if the intensity or duration of PEF treatment is too high, the quality of duck meat will actually decrease. Therefore, appropriate parameters should be selected in practical applications, which will provide a reference for the application of PEF-assisted thawing on the market.

Marine peptides as potential anti-aging agents: Preparation, characterization, mechanisms of action, and future perspectives

Aging is a universal biological process characterized by a decline in physiological functions, leading to increased susceptibility to diseases. With global aging trends, understanding and mitigating the aging process is paramount. Recent studies highlight marine peptides as promising bioactive substances with potential anti-aging properties. This review critically examines the potential of marine peptides as novel food ingredients in anti-aging, exploring their sources, preparation methods, physicochemical properties, and the underlying mechanisms through which they impact the aging process. Marine peptides exhibit significant potential in targeting aging, extending lifespan, and enhancing healthspan. They act through mechanisms such as reducing oxidative stress and inflammation, modulating mitochondrial dysfunction, inducing autophagy, maintaining extracellular matrix homeostasis, and regulating longevity-related pathways. Despite challenges in stability, bioavailability, and scalability, marine peptides offer significant potential in health, nutraceuticals, and pharmaceuticals, warranting further research and development in anti-aging.

Pulsed Electric Fields Effects on Proteins: Extraction, Structural Modification, and Enhancing Enzymatic Activity

Pulsed electric field (PEF) is an innovative physical method for food processing characterized by low energy consumption and short processing time. This technology represents a sustainable procedure to extend food shelf-life, enhance mass transfer, or modify food structure. The main mechanism of action of PEF for food processing is the increment of the permeability of the cell membranes by electroporation. However, it has also been shown that PEF may modify the technological and functional properties of proteins. Generating a high-intensity electric field necessitates the flow of an electric current that may have side effects such as electrochemical reactions and temperature increments due to the Joule effect that may affect food components such as proteins. This article presents a critical review of the knowledge on the extraction of proteins assisted by PEF and the impact of these treatments on protein composition, structure, and functionality. The required research for understanding what happens to a protein when it is under the action of a high-intensity electric field and to know if the mechanism of action of PEF on proteins is different from thermal or electrochemical effects is underlying.

Algae-derived compounds: Bioactivity, allergenicity and technologies enhancing their values

As a rapidly growing source of human nutrients, algae biosynthesize diverse metabolites which have promising bioactivities. However, the potential allergenicity of algal components hinder their widespread adoption. This review provides a comprehensive review of various macro and micronutrients derived from algal biomass, with particular focus on bioactive compounds, including peptides, polyphenols, carotenoids, omega-3 fatty acids and phycocyanins. The approaches used to produce algal bioactive compounds and their health benefits (antioxidant, antidiabetic, cardioprotective, anti-inflammatory and immunomodulatory) are summarised. This review particularly focuses on the state-of-the-art of precision fermentation, encapsulation, cold plasma, high-pressure processing, pulsed electric field, and subcritical water to reduce the allergenicity of algal compounds while increasing their bioactivity and bioavailability. By providing insights into current challenges of algae-derived compounds and opportunities for advancement, this review contributes to the ongoing discourse on maximizing their application potential in the food nutraceuticals, and pharmaceuticals industries.

Pomegranate seed as a novel source of plant protein: Optimization of protein extraction and evaluation of in vitro digestibility, functional, and thermal properties

This research was carried out to optimize the extraction process of proteins from pomegranate seeds and characterize their in vitro digestibility as well as their thermal and functional properties. For this purpose, the study screened five parameters (liquid/solid ratio, pH, temperature, NaCl concentration, and time) that could potentially influence the extraction process. This screening was conducted using a two-level Placket-Burman design (PBD). The significant parameters (pH and NaCl concentration) were subsequently optimized using a three-level face-centered central composite design (FCCD) to determine the optimum extraction conditions. A maximum protein recovery of 83.8% was obtained at pH 11.0 and NaCl concentration of 0.0 M. Pomegranate seed protein isolate (PSPI) with a protein content of 92.4% (w/w) was obtained through the isoelectric precipitation of pomegranate seed protein extracted under the optimized conditions. An emulsifying activity index of 14.1 m2 g-1 was observed at the isoelectric pH, where the emulsion stability index was at 8.2%. PSPI also showed high water- and oil-holding capacities (3.7 and 4.3 g g-1, respectively). The essential amino acid levels in PSPI (except for valine and isoleucine) exceeded the recommended amounts set by WHO/FAO/UNU for adults, highlighting its high nutritional value. Based on thermal analysis data, denaturation of PSPI could occur at 89.5°C. The in vitro digestibility of PSPI was found to be 74.3%. PSPI shows a potential as a novel ingredient for substituting animal-based proteins in various food applications.

Mechanistic understanding of the improved drying characteristics and quality attributes of lily (Lilium lancifolium Thunb.) by modified microstructure after pulsed electric field (PEF) pretreatment

The effects of the non-thermal (pulsed electric field, PEF) and thermal pretreatment (vacuum steam pulsed blanching, VSPB) on the drying kinetics, quality attributes, and multi-dimensional microstructure of lily scales were investigated. The results indicate that both PEF and VSPB pretreatments improved the drying rate compared to untreated lily scales. Specifically, PEF pretreatment reduced the drying time by 29.58 % - 43.60 %, while VSPB achieved a 46.91 % reduction in drying time. PEF treatment facilitated the enhanced leaching of phenols and flavonoids compared to VSPB treated samples, thereby increasing antioxidant activity. The rehydration ratio of the dried lilies was improved with PEF and VSPB treatment, which closely related to the microstructure. Weibull distribution and Page model demonstrated excellent fit for the drying and rehydration kinetics of lily scales, respectively (R2 > 0.993). The analysis of multi-dimensional microstructure and ultrastructure confirmed the variations in moisture migration and phytochemical contents among different treatments. Consequently, this study offers insights into the technological support for the potential of non-thermal pretreatment in fruits and vegetables.

From feed to functionality: Unravelling the nutritional composition and techno-functional properties of insect-based ingredients

In recent years, there has been a growing interest in using insects as a sustainable resource for biorefinery processes. This emerging field aims to convert insect biomass into valuable products while minimizing waste. The integration of emerging green technologies and the efficient extraction of high-value compounds from insects offer promising avenues for addressing the growing demand for sustainable food production and resource utilization. The review examines the impact of dietary modifications on the nutritional profile of insects. It highlights the potential for manipulating insect feed to optimize protein quality, amino acid profile, lipid content and fatty acid composition. Additionally, innovative green processing technologies such as ultrasound, high pressure processing, pulsed electric fields, cold plasma and enzymatic hydrolysis are discussed for their ability to enhance the extraction and techno-functional properties of insect-based ingredients. The review finds that dietary modifications can impact the nutritional composition of insects, allowing the customization of their nutrient content. By optimizing the insect feed, it is possible to increase the quantity and improve the quality of essential nutrients like proteins or lipids in the derived ingredients. Moreover, alternative processing technologies can improve the techno-functional properties (e.g., solubility, water and oil holding capacities, among others) of insect-based ingredients by modifying proteins' conformation. By harnessing these strategies, researchers and industry professionals can unlock the full potential of insects as a sustainable and nutritional food source, paving the way for innovative insect-based food products.

Fermented Vegetables: Health Benefits, Defects, and Current Technological Solutions

This review summarizes current studies on fermented vegetables, analyzing the changes in nutritional components during pickling, the health benefits of fermented vegetables, and their safety concerns. Additionally, the review provides an overview of the applications of emergent non-thermal technologies for addressing these safety concerns during the production and processing of fermented vegetables. It was found that vitamin C would commonly be lost, the soluble protein would degrade into free amino acids, new nutrient compositions would be produced, and the flavor correlated with the chemical changes. These changes would be influenced by the variety/location of raw materials, the original bacterial population, starter cultures, fermentation conditions, seasoning additions, and post-fermentation processing. Consuming fermented vegetables benefits human health, including antibacterial effects, regulating intestinal bacterial populations, and promoting health (anti-cancer effects, anti-diabetes effects, and immune regulation). However, fermented vegetables have chemical and biological safety concerns, such as biogenic amines and the formation of nitrites, as well as the existence of pathogenic microorganisms. To reduce hazardous components and control the quality of fermented vegetables, unique starter cultures, high pressure, ultrasound, cold plasma, photodynamic, and other technologies can be used to solve these problems.

Non-thermal technologies for the conservation of açai pulp and derived products: A comprehensive review

Açai (Euterpe oleracea) is one of the main sustainable extractive crops in the Amazon region, widely consumed by the local population and a significant export product. This review presents the current knowledge regarding nonthermal technologies employed in açai processing. This review aims to discuss and compare the main results attained by the application of HPP, ultrasound, ozone, UV light, cold plasma, and pulsed electric field on microbial inactivation, enzymatic inhibition, and the content of anthocyanin and other bioactive compounds after açai pulp processing. The discussion compares these technologies with pasteurization, the current main technology applied to açai sanitization. This review shows that there are still many gaps to be filled concerning açai processing in thermal and non-thermal technologies. Data analysis allowed the conclusion that pasteurization and HPP are, up to now, the only technologies that enable a 5-log CFU reduction of yeasts, molds, and some bacteria in açai. However, no study has reported the inactivation of Trypanosoma cruzi, which is the major gap found in current knowledge. Other technologies, such as pulsed electric field, cold plasma, and ultrasound, require further development and process intensification studies to be as successful as HPP and pasteurization.

Enhancing activity of food protein-derived peptides: An overview of pretreatment, preparation, and modification methods

Food protein-derived peptides have garnered considerable attention due to their potential bioactivities and functional properties. However, the limited activity poses a challenge in effective utilization aspects. To overcome this hurdle, various methods have been explored to enhance the activity of these peptides. This comprehensive review offers an extensive overview of pretreatment, preparation methods, and modification strategies employed to augment the activity of food protein-derived peptides. Additionally, it encompasses a discussion on the current status and future prospects of bioactive peptide applications. The review also addresses the standardization of mass production processes and safety considerations for bioactive peptides while examining the future challenges and opportunities associated with these compounds. This comprehensive review serves as a valuable guide for researchers in the food industry, offering insights and recommendations to optimize the production process of bioactive peptides.

Non-thermal techniques as an approach to modify the structure of milk proteins and improve their functionalities: a review of novel preparation

BACKGROUND

Milk proteins (MPs) have been widely used in the food industry due to their excellent functionalities. However, MPs are thermal-unstable substances and their functional properties are easily affected by heat treatment. Emerging non-thermal approaches (i.e., high-pressure homogenization (HPH), ultrasound (US), pulsed electric field (PEF)) have been increasingly popular. A detailed understanding of these approaches' impacts on the structure and functionalities of MPs can provide theoretical guidance for further development to accelerate their industrialization.

SCOPE AND APPROACH

This review assesses the mechanisms of HPH, US and PEF technologies on the structure and functionalities of MPs from molecular, mesoscopic and macroscopic levels, elucidates the modifications of MPs by these theologies combined with other methods, and further discusses their existing issues and the development in the food filed.

KEY FINDINGS AND CONCLUSIONS

The structure of MPs changed after HPH, US and PEF treatment, affecting their functionalities. The changes in these properties of MPs are related to treated-parameters of used-technologies, the concentration of MPs, as well as molecular properties. Additionally, these technologies combined with other methods could obtain some outstanding functional properties for MPs. If properly managed, these theologies can be tailored for manufacturing superior functional MPs for various processing fields.

Sea Bass Side Streams Extracts Obtained by Pulsed Electric Fields: Nutritional Characterization and Effect on SH-SY5Y Cells

Fish side streams are an environmental and economic problem. In this work, pulsed electric fields (PEF) extraction was optimized and used as a new method for their valorization. Sea bass head, skin, viscera, and backbone were used. PEF technology (123-300 kJ/kg, 1-3 kV/cm) improved the extraction of proteins and antioxidant compounds from head and skin, but was not successful for viscera. SDS-PAGE showed that the protein molecular weight distribution was affected by the extraction process, revealing differences between the control and PEF extraction conditions. In addition, the extraction of macro-minerals and micro-minerals were also evaluated. The effect of PEF differed according to the matrix and the mineral studied. Heavy metals were also taken into account, studying the presence of As, Cd, Hg, and Pb in the extracts. PEF pre-treatment reduced the presence of As in skin, viscera, and backbone, ranging from 18.25 to 28.48% according to the matrix evaluated. The analysis of potential antioxidant bioactive peptides showed that the treatment of the sample directly influenced their variety. Additionally, the extracts obtained from the head were found to increase cell viability when tested on SH-SY5Y cells. In conclusion, PEF extraction can be a useful tool for the valorization of fish side streams.

A review of oil and water retention in emulsified meat products: The mechanisms of gelation and emulsification, the application of multi-layer hydrogels

Emulsified meat products are key deep-processing products due to unique flavor and high nutritional value. Myosin dissolves, and protein aggregation and heat-induced gelation occur after myosin unfolds and hydrophobic groups are exposed. Myosin could form interfacial protein membranes and wrap fat globules. Emulsified fat globules may be filled in heat-induced gel networks. Therefore, this review intends to discuss the influences of heat-induced gelation and interfacial adsorption behavior on oil and water retention. Firstly, the mechanism of heat-induced gelation was clarified from the perspective of protein conformation and micro-structure. Secondly, the mechanism of emulsification stability and its factors affecting interfacial adsorption were demonstrated as well as limitations and challenges. Finally, the structure characteristics and application of multi-layer hydrogels in the gelation and emulsification were clarified. It could conclude that the characteristic morphology, spatial conformation and structure adjustment affected heat-induced gelation and interfacial adsorption behavior. Spatial conformation and microstructure were adjusted to improve the oil and water retention by pH, ionic strength, amino acid, oil phase characteristic and protein interaction. Multi-layer hydrogels facilitated oil and water retention. The comprehensive review of gelation and emulsification mechanisms could promote the development of meat products and improvement of meat processing technology.

Developments in Plant Proteins Production for Meat and Fish Analogues

In recent years, there have been significant developments in plant proteins production for meat and fish analogues. Some of the key developments include the use of new plant protein sources such as soy, legumes, grains, potatoes, and seaweed, as well as insect proteins, leaf proteins, mushrooms, and microbial proteins. Furthermore, to improve the technological and functional properties of plant proteins, they can be subjected to traditional and unconventional treatments such as chemical (glycosylation, deamidation, phosphorylation, and acylation), physical (pulsed electric fields, ultrasound, high hydrostatic pressure, dynamic high-pressure treatment, and cold plasma), and biological (fermentation and enzymatic modification). To obtain the high quality and the desired texture of the food product, other ingredients besides proteins, such as water, fat, flavors, binders, dyes, vitamins, minerals, and antioxidants, also have to be used. The final product can be significantly influenced by the matrix composition, variety of ingredients, and water content, with the type of ingredients playing a role in either enhancing or constraining the desired texture of the food. There are several types of technologies used for meat and fish analogues production, including extrusion, shear cell technology, spinning, 3D printing, and others. Overall, the technologies used for meat and fish analogues production are constantly evolving as new innovations are developed and existing methods are improved. These developments have led to the creation of plant-based products that have a similar texture, taste, and nutritional profile to meat and fish, making them more appealing to consumers seeking alternatives to animal-based products.

Allergenicity of peanut allergens and its dependence on the structure

Food allergies are a global food safety problem. Peanut allergies are common due, in part, to their popular utilization in the food industry. Peanut allergy is typically an immunoglobulin E-mediated reaction, and peanuts contain 17 allergens belonging to different families in peanut. In this review, we first introduce the mechanisms and management of peanut allergy, followed by the basic structures of associated allergens. Subsequently, we summarize methods of epitope localization for peanut allergens. These methods can be instrumental in speeding up the discovery of allergenicity-dependent structures. Many attempts have been made to decrease the allergenicity of peanuts. The structures of hypoallergens, which are manufactured during processing, were analyzed to strengthen the desensitization process and allergen immunotherapy. The identification of conformational epitopes is the bottleneck in both peanut and food allergies. Further, the identification and modification of such epitopes will lead to improved strategies for managing and preventing peanut allergy. Combining traditional wet chemistry research with structure simulation studies will help in the epitopes' localization.

Advances in pulsed electric stimuli as a physical method for treating liquid foods

There is a need for alternative technologies that can deliver safe and nutritious foods at lower costs as compared to conventional processes. Pulsed electric field (PEF) technology has been utilised for a plethora of different applications in the life and physical sciences, such as gene/drug delivery in medicine and extraction of bioactive compounds in food science and technology. PEF technology for treating liquid foods involves engineering principles to develop the equipment, and quantitative biochemistry and microbiology techniques to validate the process. There are numerous challenges to address for its application in liquid foods such as the 5-log pathogen reduction target in food safety, maintaining the food quality, and scale up of this physical approach for industrial integration. Here, we present the engineering principles associated with pulsed electric fields, related inactivation models of microorganisms, electroporation and electropermeabilization theory, to increase the quality and safety of liquid foods; including water, milk, beer, wine, fruit juices, cider, and liquid eggs. Ultimately, we discuss the outlook of the field and emphasise research gaps.

Impacts of Electroextraction Using the Pulsed Electric Field on Properties of Rice Bran Protein

The pulsed electric field (PEF) was applied to improve the extraction yield and properties of rice bran proteins from two rice varieties ("Kum Chao Mor Chor 107" and "Kum Doi Saket"). As compared to the conventional alkaline extraction, PEF treatment at 2.3 kV for 25 min increased the protein extraction efficiency by 20.71-22.8% (p < 0.05). The molecular weight distribution detected by SDS-PAGE and amino acid profiles of extracted rice bran proteins was likely unchanged. The PEF treatment influenced changes in the secondary structures of rice bran proteins, especially from the β-turn to the β-sheet structure. Functional properties of rice bran protein including oil holding capacity and emulsifying properties were significantly improved by PEF treatments by about 20.29-22.64% and 3.3-12.0% (p < 0.05), respectively. Foaming ability and foam stability increased by 1.8- to 2.9-fold. Moreover, the in vitro digestibility of protein was also enhanced, which was consistent with the increment of DPPH and ABTS radical-scavenging activities of peptides generated under in vitro gastrointestinal digestion (37.84-40.45% and 28.46-37.86%, respectively). In conclusion, the PEF process could be a novel technique for assisting the extraction and modification of the protein's digestibility and functional properties.

A robust local pulse wave imaging method based on digital image processing techniques

The original diameter velocity loop method (ln(D)U-loop) cannot accurately extract the blood vessel diameter waveform when the quality of ultrasound image data is not high (such as obesity, age, and the operation of the ultrasound doctor), so it is unable to measure the pulse wave velocity (PWV) of the ascending aorta. This study proposes a diameter waveform extraction method combining threshold, gradient filtering, and the center of gravity method. At the same time, the linear regression method of searching for the rising point of the systolic period is replaced by the optimal average of two linear regression methods. This method can also extract the diameter waveform with poor-quality images and obtain a more accurate PWV. In vivo experimental data from 17 (age 60.5 ± 9.2) elderly patients with cerebral infarction and 12 (age 32.5 ± 5.6) healthy young adults were used for processing, and the results showed that the mean PWV using the ln(D)U-loop method was 12.56 (SD = 3.47) ms-1 for patients with cerebral infarction and 6.81 (SD = 1.73) ms-1 for healthy young adults. The PWV results based on the Wilcoxon rank-sum test and calculated based on the improved ln(D)U-loop method were both statistically significant (p < 0.01). The agreement analysis (Bland-Altman analysis) between the QA-loop and ln(D)U-loop methods showed that the mean deviation of the measured PWV was 0.07 m/s and the standard deviation of the deviation was 1.18 m/s. The experimental results demonstrated the effectiveness of the improved ln(D)U-loop method proposed in this paper on poor-quality images. This study can improve the possibility of the ln(D)U-loop method being widely used in the clinical measurement of ascending aortic PWV.

Investigation of Consequences of High-Voltage Pulsed Electric Field and TGase Cross-Linking on the Physicochemical and Rheological Properties of Pleurotus eryngii Protein

This study aimed to evaluate the effects of high-voltage pulsed electric fields (HPEF) and transglutaminase (TGase) cross-clinking on the physicochemical and rheological properties of Pleurotus eryngii protein (PEP). The results showed that HPEF increased α-helixes and β-turns but decreased β-folds. A HPEF at 1500 V/cm maximized the free sulfhydryl content and solubility of PEP. TGase formed high-molecular-weight polymers in PEP. TGase at 0.25% maximized the free sulfhydryl groups, particle size, and solubility; shifted the maximum absorption wavelength from 343 nm to 339 nm and 341 nm; increased α-helixes and β-turns and decreased β-folds; and showed better rheological properties. Compared with TGase cross-linking, HPEF-1500 V/cm and 1% TGase significantly reduced the free sulfhydryl groups, particle size, and solubility, produced more uniform network structures, and improved the rheological properties. These results suggest that HPEF can increase the cross-linking of TGase and improve rheological properties of TGase-cross-linked PEP by affecting the physicochemical properties.

Electro-detachment of kinesin motor domain from microtubule in silico

Kinesin is a motor protein essential in cellular functions, such as intracellular transport and cell-division, as well as for enabling nanoscopic transport in bio-nanotechnology. Therefore, for effective control of function for nanotechnological applications, it is important to be able to modify the function of kinesin. To circumvent the limitations of chemical modifications, here we identify another potential approach for kinesin control: the use of electric forces. Using full-atom molecular dynamics simulations (247,358 atoms, total time ∼ 4.4 μs), we demonstrate, for the first time, that the kinesin-1 motor domain can be detached from a microtubule by an intense electric field within the nanosecond timescale. We show that this effect is field-direction dependent and field-strength dependent. A detailed analysis of the electric forces and the work carried out by electric field acting on the microtubule-kinesin system shows that it is the combined action of the electric field pulling on the β-tubulin C-terminus and the electric-field-induced torque on the kinesin dipole moment that causes kinesin detachment from the microtubule. It is shown, for the first time in a mechanistic manner, that an electric field can dramatically affect molecular interactions in a heterologous functional protein assembly. Our results contribute to understanding of electromagnetic field-biomatter interactions on a molecular level, with potential biomedical and bio-nanotechnological applications for harnessing control of protein nanomotors.

Transformation of Seafood Side-Streams and Residuals into Valuable Products

Seafood processing creates enormous amounts of side-streams. This review deals with the use of seafood side-streams for transformation into valuable products and identifies suitable approaches for making use of it for different purposes. Starting at the stage of catching fish to its selling point, many of the fish parts, such as head, skin, tail, fillet cut-offs, and the viscera, are wasted. These parts are rich in proteins, enzymes, healthy fatty acids such as monounsaturated and polyunsaturated ones, gelatin, and collagen. The valuable biochemical composition makes it worth discussing paths through which seafood side-streams can be turned into valuable products. Drawbacks, as well as challenges of different aquacultures, demonstrate the importance of using the various side-streams to produce valuable compounds to improve economic performance efficiency and sustainability of aquaculture. In this review, conventional and novel utilization approaches, as well as a combination of both, have been identified, which will lead to the development of sustainable production chains and the emergence of new bio-based products in the future.

Structural Transitions of Alpha-Amylase Treated with Pulsed Electric Fields: Effect of Coexisting Carrageenan

Pulsed electric field (PEF) is an effective way to modulate the structure and activity of enzymes; however, the dynamic changes in enzyme structure during this process, especially the intermediate state, remain unclear. In this study, the molten globule (MG) state of α-amylase under PEF processing was investigated using intrinsic fluorescence, surface hydrophobicity, circular dichroism, etc. Meanwhile, the influence of coexisting carrageenan on the structural transition of α-amylase during PEF processing was evaluated. When the electric field strength was 20 kV/cm, α-amylase showed the unique characteristics of an MG state, which retained the secondary structure, changed the tertiary structure, and increased surface hydrophobicity (from 240 to 640). The addition of carrageenan effectively protected the enzyme activity of α-amylase during PEF treatment. When the mixed ratio of α-amylase to carrageenan was 10:1, they formed electrostatic complexes with a size of ~20 nm, and carrageenan inhibited the increase in surface hydrophobicity (<600) and aggregation (<40 nm) of α-amylase after five cycles of PEF treatment. This work clarifies the influence of co-existing polysaccharides on the intermediate state of proteins during PEF treatment and provides a strategy to modulate protein structure by adding polysaccharides during food processing.

Potential applications of pulsed electric field in the fermented wine industry

Fermented wine refers to alcoholic beverages with complex flavor substances directly produced by raw materials (fruit or rice) through microbial fermentation (yeast and bacteria). Its production steps usually include saccharification, fermentation, filtration, sterilization, aging, etc., which is a complicated and time-consuming process. Pulsed electric field (PEF) is a promising non-thermal food processing technology. Researchers have made tremendous progress in the potential application of PEF in the fermented wine industry over the past few years. The objective of this paper is to systematically review the achievements of PEF technology applied to the winemaking and aging process of fermented wine. Research on the application of PEF in fermented wine suggests that PEF treatment has the following advantages: (1) shortening the maceration time of brewing materials; (2) promoting the extraction of main functional components; (3) enhancing the color of fermented wine; (4) inactivating spoilage microorganisms; and (5) accelerating the formation of aroma substances. These are mainly related to PEF-induced electroporation of biomembranes, changes in molecular structure and the occurrence of chemical reactions. In addition, the key points of PEF treatments for fermented wine are discussed and some negative impacts and research directions are proposed.

Pulsed electric field-assisted drying: A review of its underlying mechanisms, applications, and role in fresh produce plant-based food preservation

Drying is a key processing step for plant-based foods. The quality of dried products, including the physical, nutritional, microbiological, and sensory attributes, is influenced by the drying method used. Conventional drying technologies have low efficiency and can negatively affect product quality. Recently, pulsed electric field (PEF)-assisted techniques are being explored as a novel pretreatment for drying. This review focuses on the application of PEF as pretreatment for drying plant-based products, the preservation effects of this pretreatment, and its underlying mechanisms. A literature search revealed that PEF-assisted drying is beneficial for maintaining the physicochemical properties of the dried products and preserving their color and constituent chemical compounds. PEF-assisted drying promotes rehydration and improves the kinetics of drying. Unlike conventional technologies, PEF-assisted drying enables selective cell disintegration while maintaining product quality. Before the drying process, PEF pretreatment inactivates microbes and enzymes and controls respiratory activity, which may further contribute to preservation. Despite numerous advantages, the efficiency and applicably of PEF-assisted drying can be improved in the future.

Impact of Pulsed Electric Fields and pH on Enzyme Inactivation and Bioactivities of Peptic Hydrolysates Produced from Bovine and Porcine Hemoglobin

The production of bioactive peptides from hemoglobin via peptic hydrolysis is a promising alternative to valorizing slaughterhouse blood proteins. Nevertheless, it has some limitations such as low yield, high cost of enzymes, and the use of chemical reagents. The latter is aggravated by the pH increase to inactivate the enzyme, which can affect the bioactivity of the peptides. Thus, this study aimed to evaluate the effect of pulsed electric fields (PEF) on the pepsin inactivation and biological activities (antimicrobial and antioxidant) of hemoglobin hydrolysates. Bovine (Hb-B) and porcine (Hb-P) hemoglobin were hydrolyzed with pepsin for 3 h and treated with PEFs to inactivate the enzyme. The degree of hydrolysis (DH) did not show significant changes after PEF inactivation, whereas peptide population analysis showed some changes in PEF-treated hydrolysates over time, suggesting residual pepsin activity. PEF treatments showed no significant positive or negative impact on antimicrobial and antioxidant activities. Additionally, the impact of pH (3, 7, and 10) on bioactivity was studied. Higher pH fostered stronger anti-yeast activity and DPPH-scavenging capacity, whereas pH 7 fostered antifungal activity. Thus, the use of hemoglobin from the meat industry combined with PEF treatments could fit the circular economy concept since bioactive peptides can be produced more eco-efficiently and recycled to reduce the spoilage of meat products. Nevertheless, further studies on PEF conditions must be carried out to achieve complete inactivation of pepsin and the potential enhancement of peptides’ bioactivity.

Mechanism of trypsin activation by pulsed electric field treatment revealed based on chemical experiments and molecular dynamics simulations

A pulsed electric field (PEF) treatment exhibits different effects on trypsin; however, the mechanism of enzyme activation remains unclear. Herein, chemical experiments combined with molecular dynamics simulations revealed the mechanism of trypsin activation by PEF treatment at the molecular level. The results indicated that compared with the values at 0 kV/cm, the enzyme activity, Vmax, and Kcat at 20 kV/cm increased by 9.30%, 4.74%, and 4.30%, respectively, and Km decreased by 11.14%, indicating an improved interaction between the enzyme and substrate. The simulation results revealed that PEF treatment increased the number of molecular hydrogen bonds and the solvent-accessible surface area, while decreasing the rotation radius and random coil content by 5.00% and 3.37%, respectively. Molecular docking indicated that PEF treatment altered the active center and increased the affinity between the enzyme and substrate. The simulation results were consistent with those of the spectroscopic experiments conducted on trypsin after PEF treatment.

Pulsed Electric Field: Fundamentals and Effects on the Structural and Techno-Functional Properties of Dairy and Plant Proteins

Dairy and plant-based proteins are widely utilized in various food applications. Several techniques have been employed to improve the techno-functional properties of these proteins. Among them, pulsed electric field (PEF) technology has recently attracted considerable attention as a green technology to enhance the functional properties of food proteins. In this review, we briefly explain the fundamentals of PEF devices, their components, and pulse generation and discuss the impacts of PEF treatment on the structure of dairy and plant proteins. In addition, we cover the PEF-induced changes in the techno-functional properties of proteins (including solubility, gelling, emulsifying, and foaming properties). In this work, we also discuss the main challenges and the possible future trends of PEF applications in the food proteins industry. PEF treatments at high strengths could change the structure of proteins. The PEF treatment conditions markedly affect the treatment results with respect to proteins' structure and techno-functional properties. Moreover, increasing the electric field strength could enhance the emulsifying properties of proteins and protein-polysaccharide complexes. However, more research and academia-industry collaboration are recommended to build highly effective PEF devices with controlled processing conditions.

Plant-derived proteins as a sustainable source of bioactive peptides: recent research updates on emerging production methods, bioactivities, and potential application

The development of novel protein sources to compensate for the expected future shortage of traditional animal proteins due to their high carbon footprint is a major contemporary challenge in the agri-food industry currently. Therefore, both industry and consumers are placing a greater emphasis on plant proteins as a sustainable source of protein to meet the growing nutritional demand of ever increasing population. In addition to being key alternatives, many plant-based foods have biological properties that make them potentially functional or health-promoting foods, particularly physiologically active peptides and proteins accounting for most of these properties. This review discusses the importance of plant-based protein as a viable and sustainable alternative to animal proteins. The current advances in plant protein isolation and production and characterization of bioactive hydrolysates and peptides from plant proteins are described comprehensively. Furthermore, the recent research on bioactivities and bioavailability of plant protein-derived bioactive peptides is reviewed briefly. The limitations of using bioactive peptides, regulatory criteria, and the possible future applications of plant protein-derived bioactive peptides are highlighted. This review may help understand plant proteins and their bioactive peptides and provide valuable suggestions for future research and applications in the food industry.

Thermal treatment alternatives for enzymes inactivation in fruit juices: Recent breakthroughs and advancements

Fruit juices (FJs) are frequently taken owing to their nutritious benefits, appealing flavour, and vibrant colour. The colours of the FJs are critical indicators of the qualitative features that influence the consumer's attention. Although FJs' intrinsic acidity serves as a barrier to bacterial growth, their enzymatic stability remains an issue for their shelf life. Inactivation of enzymes is critical during FJ processing, and selective inactivation is the primary focus of enzyme inactivation. The merchants, on the other hand, want the FJs to stay stable. The most prevalent technique of processing FJ is by conventional heat treatment, which degrades its nutritive value and appearance. The FJ processing industry has undergone a dramatic transformation from thermal treatments to nonthermal treatments (NTTs) during the past two decades to meet the requirements for microbiological and enzymatic stability. The manufacturers want safe and stable FJs, while buyers want high-quality FJs. According to the past investigation, NTTs have the potential to manufacture microbiologically safe and enzymatically stable FJs with low loss of bioactive components. Furthermore, it has been demonstrated that different NTTs combined with or without other NTTs or mild heating as a hurdle technology increase the synergistic effect for microbiological safety and stability of FJs. Concise information about the variables that affect NTTs' action mode has also been addressed. Primary inactivates enzymes by modifying the protein structure and active site conformation. NTTs may increase enzyme activity depending on the nature of the enzyme contained in FJs, the applied pressure, pH, temperature, and treatment period. This is due to the release of membrane-bound enzymes as well as changes in protein structure and active sites that allow substrate interaction. Additionally, the combination of several NTTs as a hurdle technology, as well as temperature and treatment periods, resulted in increased enzyme inactivation in FJs. Therefore, a combination of thermal and non-thermal technologies is suggested to increase the effectiveness of the process as well as preserve the juice quality.

Effect of high-intensity ultrasound on the structural, rheological, emulsifying and gelling properties of insoluble potato protein isolates

The denaturation and lower solubility of commercial potato proteins generally limited their industrial application. Effects of high-intensity ultrasound (HIU) (200, 400, and 600 W) and treatment time (10, 20, and 30 min) on the physicochemical and functional properties of insoluble potato protein isolates (ISPP) were investigated. The results revealed that HIU treatment induced the unfolding and breakdown of macromolecular aggregates of ISPP, resulting in the exposure of hydrophobic and R-SH groups, and reduction of the particle size. These active groups contributed to the formation of a dense and uniform gel network of ISPP gel and insoluble potato proteins/egg white protein (ISPP/EWP) hybrid gel. Furthermore, the increase of solubility and surface hydrophobicity and the decrease of particle size improved the emulsifying property of ISPP. However, excessive HIU treatment reduced the emulsification and gelling properties of the ISPP. Meanwhile, HIU treatment changes the secondary structure of ISPP. It could be speculated that the formation of a stable secondary structure of ISPP initiated by cavitation and shearing effect might play a dominant role on gel strengthens and firmness. Meanwhile, the decrease in relative content of β-turn had a positive effect on the formation of small particle to improve emulsifying property of ISPP.

Application of emerging technologies to obtain legume protein isolates with improved techno-functional properties and health effects

Current demand of consumers for healthy and sustainable food products has led the industry to search for different sources of plant protein isolates and concentrates. Legumes represent an excellent nonanimal protein source with high-protein content. Legume species are distributed in a wide range of ecological conditions, including regions with drought conditions, making them a sustainable crop in a context of global warming. However, their use as human food is limited by the presence of antinutritional factors, such as protease inhibitors, lectins, phytates, and alkaloids, which have adverse nutritional effects. Antitechnological factors, such as fiber, tannins, and lipids, can affect the purity and protein extraction yield. Although most are removed or reduced during alkaline solubilization and isoelectric precipitation processes, some remain in the resulting protein isolates. Selection of appropriate legume genotypes and different emerging and sustainable facilitating technologies, such as high-power ultrasound, pulsed electric fields, high hydrostatic pressure, microwave, and supercritical fluids, can be applied to increase the removal of unwanted compounds. Some technologies can be used to increase protein yield. The technologies can also modify protein structure to improve digestibility, reduce allergenicity, and tune technological properties. This review summarizes recent findings regarding the use of emerging technologies to obtain high-purity protein isolates and the effects on techno-functional properties and health.

Marine Products As a Promising Resource of Bioactive Peptides: Update of Extraction Strategies and Their Physiological Regulatory Effects

Marine products are a rich source of nutritional components and play important roles in promoting human health. Fish, mollusks, shellfish, as well as seaweeds are the major components of marine products with high-quality proteins. During the last several decades, bioactive peptides from marine products have gained much attention due to their diverse biological properties including antioxidant, antihypertensive, antimicrobial, antidiabetic, immunoregulation, and antifatigue. The structural characteristics of marine bioactive peptides largely determine the differences in signaling pathways that can be involved, which is also an internal mechanism to exert various physiological regulatory activities. In addition, the marine bioactive peptides may be used as ingredients in food or nutritional supplements with the function of treating or alleviating chronic diseases. This review presents an update of marine bioactive peptides with the highlights on the novel producing technologies, the physiological effects, as well as their regulation mechanisms. Challenges and problems are also discussed in this review to provide some potential directions for future research.

Food Processing Technologies to Develop Functional Foods With Enriched Bioactive Phenolic Compounds in Cereals

Cereal grains and products provide calories globally. The health benefits of cereals attributed to their diverse phenolic constituents have not been systematically explored. Post-harvest processing, such as drying, storing, and milling cereals, can alter the phenolic concentration and influence the antioxidant activity. Furthermore, cooking has been shown to degrade thermo-labile compounds. This review covers several methods for retaining and enhancing the phenolic content of cereals to develop functional foods. These include using bioprocesses such as germination, enzymatic, and fermentation treatments designed to enhance the phenolics in cereals. In addition, physical processes like extrusion, nixtamalization, and parboiling are discussed to improve the bioavailability of phenolics. Recent technologies utilizing ultrasound, micro- or nano-capsule polymers, and infrared utilizing processes are also evaluated for their effectiveness in improving the phenolics content and bio-accessibility. We also present contemporary products made from pigmented cereals that contain phenolics.