High Hydrostatic Pressure Research Articles

Preservation Techniques to Increase the Shelf Life of Seafood Products: An Overview

Currently, humanity is facing many types of diseases with various origins and the high costs of chemical drugs for treatment. Therefore, the consumption of healthy and nourishing foods such as seafood products to treat these diseases should be considered in the human diet. However, seafood products are subject to high spoilage owing to their high-water content, rich composition of unsaturated fatty acids, susceptibility to oxidation, near-neutral pH, presence of non-protein nitrogenous compounds, and microorganism activity. Therefore, appropriate storage methods are required to prevent spoilage. This review was done with the aim of providing preservation methods and increasing the shelf life of seafood products. In general, the results of this research stated that common and traditional techniques of seafood products preservation including salting, canning, chilling, freezing, fermentation, super chilling, drying, smoking, frying, pickling/marinating and pasteurization and also modern techniques for seafood products preservation such as microwave processing, ultrasound, pulsed electric field (PEF), irradiation, high hydrostatic pressure (HHP), micro fluidization, usage of natural preservatives (plants and algae extracts, biodegradable polymers, bioactive polysaccharides and biopeptides extracted from marine resources/ seafood by-products), packaging ((MAP), (AP), (IP), (VP), (RP)), nanotechnology and other new methods can preserve the product for a period of time efficiently, also significantly increase the desired sensory and organoleptic characteristics of the product and as a result, they increase quality, safety and shelf life. However, improving the weaknesses of traditional methods by using modern techniques can improve and maintain the nutritional value of the product.

Genome sequencing of Coryphaenoides yaquinae reveals convergent and lineage‐specific molecular evolution in deep‐sea adaptation

AbstractAbyssal (3501–6500 m) and hadal (>6500 m) fauna evolve under harsh abiotic stresses, characterized by high hydrostatic pressure, darkness and food shortage, providing unique opportunities to investigate mechanisms underlying environmental adaptation. Genomes of several hadal species have recently been reported. However, the genetic adaptation of deep sea species across a broad spectrum of ocean depths has yet to be thoroughly investigated, due to the challenges imposed by collecting the deep sea species. To elucidate the correlation between genetic innovation and vertical distribution, we generated a chromosome‐level genome assembly of the macrourids Coryphaenoides yaquinae, which is widely distributed in the abyssal/hadal zone ranging from 3655 to 7259 m in depth. Genomic comparisons among shallow, abyssal and hadal‐living species identified idiosyncratic and convergent genetic alterations underlying the extraordinary adaptations of deep‐sea species including light perception, circadian regulation, hydrostatic pressure and hunger tolerance. The deep‐sea fishes (Coryphaenoides Sp. and Pseudoliparis swirei) venturing into various ocean depths independently have undergone convergent amino acid substitutions in multiple proteins such as rhodopsin 1, pancreatic and duodenal homeobox 1 and melanocortin 4 receptor which are known or verified in zebrafish to be related with vision adaptation and energy expenditure. Convergent evolution events were also identified in heat shock protein 90 beta family member 1 and valosin‐containing protein genes known to be related to hydrostatic pressure adaptation specifically in fishes found around the hadal range. The uncovering of the molecular convergence among the deep‐sea species shed new light on the common genetic innovations required for deep‐sea adaptation by the fishes.

Transcript level of telomerase reverse-transcriptase (TERT) gene in the rainbow trout (Oncorhynchus mykiss) eggs with different developmental competence for gynogenesis.

Expression of the telomerase reverse-transcriptase (TERT) gene and activity of telomerase have been reported in the somatic tissues and gonads in fish irrespective of their age and size. Nevertheless, little is known about TERT expression in the fish eggs. In the current study, the presence of the TERT transcripts was confirmed in the rainbow trout ovulated eggs before and after activation with nonirradiated and UV-irradiated (gynogenesis) sperm. Eggs originating from eight females had high and comparable quality expressed by similar hatching rates. However, survival of the gynogenetic larvae that hatched from eggs activated with UV-irradiated sperm and further exposed to the high hydrostatic pressure (HHP) shock for duplication of the maternal chromosomes varied between females from 2.1 ± 0.4 to 40.5 ± 2.2%. Increased level of TERT transcripts was observed in eggs originating from two females, and gametes from only one of them showed improved competence for gynogenesis (27.3 ± 1.9%). In turn, eggs from the female that exhibited the highest survival after gynogenetic activation were characterized by the lowest expression of the TERT gene. Telomerase in rainbow trout eggs may compensate erosion of the telomeres during early embryonic development; however, its upregulation does not assure better development after gynogenetic activation.

Study on impermeability of reinforced concrete wall with horizontal construction joints

The reinforced concrete (RC) water retaining tank walls with horizontal construction joints are prone to experiencing seepage under high hydrostatic pressure, which can affect the structural integrity and functionality. To evaluate the impermeability of construction joints with different improvement measures, the permeability test of concrete with and without horizontal construction joints was conducted. The test results show that the addition of Polypropylene fibers (PP fiber) and Cementitious Capillary Crystalline Waterproofing materials (CCCW) can improve the self-waterproofing ability of concrete. The impermeability at the construction joint is much lower than that of single-casting concrete. Moreover, applying CCCW to the water-facing surface of the construction joint can significantly enhance its impermeability. Then, two 1:2 scaled RC tank wall specimens were manufactured, with one wall of conventional concrete and the other wall of modified concrete. The impermeability tests of the typical single-casting and double-layer casting parts of the two wall specimens were carried out respectively. The experimental results show the RC tank wall with construction joint is prone to generate initial defects and seepage, making it difficult to achieve the design watertight requirements. The use of modified concrete materials and surface treatment in the relevant part can effectively improve the impermeability performance of the construction joint. Finally, the BP neural network was used to establish a prediction model between the impermeability of concrete and its material parameters and construction technology.

Application of thermally assisted high hydrostatic pressure to modify sorghum starch: multi-scale structure, techno-functional properties and digestibility

Application of thermally assisted high hydrostatic pressure to modify sorghum starch: multi-scale structure, techno-functional properties and digestibility

Structural and thermodynamic characterization of a highly amyloidogenic dimer of transthyretin involved in a severe cardiomyopathy

Transthyretin (TTR) is a homotetrameric protein involved in the transport of thyroxine. More than 150 different mutations have been described in the TTR gene, several of them associated with familial amyloid cardiomyopathy (FAC). Recently, our group described a new variant of TTR in Brazil, namely A39D-TTR, which causes a severe cardiac condition. Position 39 is in the AB loop, a region of the protein that is located within the thyroxine-binding channels and is involved in tetramer formation. In the present study we solved the structure and characterize the thermodynamic stability of this new variant of TTR using urea and high hydrostatic pressure (HHP). Interestingly, during the process of purification, A39D-TTR turned out to be a dimer and not a tetramer, a variation that might be explained by the close contact of the four aspartic acids at position 39, where they face each other inside the thyroxine channel. In the presence of sub-denaturing concentrations of urea, bis-ANS binding and dynamic light scattering revealed A39D-TTR in the form of a molten-globule dimer. Co-expression of A39D and WT isoforms in the same bacterial cell did not produce heterodimers or heterotetramers, suggesting that somehow a negative charge at the AB loop precludes tetramer formation. A39D-TTR proved to be highly amyloidogenic, even at mildly acidic pH values where WT-TTR does not aggregate. Interestingly, despite being a dimer, aggregation of A39D-TTR was inhibited by diclofenac, which binds to the thyroxine channel in the tetramer, suggesting the existence of other pockets in A39D-TTR able to accommodate this molecule.

Biogenic Amines in Seafood

Biogenic amines (BAs) are organic compounds naturally formed in foods through the microbial decarboxylation of amino acids. These compounds are particularly significant in seafood due to the high susceptibility of these products to microbial contamination and improper storage conditions. Biogenic amines, including histamine, tyramine, putrescine, and cadaverine, are often indicators of food freshness and spoilage. Their presence at high levels can pose serious health risks to consumers, making the study of their formation, types, and control methods crucial for food safety. This comprehensive review examines the mechanisms underlying the formation of biogenic amines in seafood. The primary sources of these compounds are bacteria from the families Enterobacteriaceae, Lactobacillaceae, and Pseudomonadaceae. Factors such as temperature, pH, and oxygen availability significantly influence bacterial activity and, consequently, biogenic amine production. Histamine is highlighted as one of the most toxic biogenic amines, capable of causing histamine poisoning, which presents symptoms such as flushing, headaches, nausea, and vomiting. Control and prevention strategies for biogenic amine formation are critically discussed, including the maintenance of the cold chain, hygienic processing techniques, salting, fermentation, and the use of starter cultures. Additionally, innovative microbial inactivation methods such as high hydrostatic pressure and UV radiation are explored for their efficacy in reducing biogenic amine levels. The review also addresses current regulations and standards set by international health authorities, particularly focusing on histamine levels in fish and fish products. These regulations ensure regular monitoring and compliance to protect consumer health. Future research directions are proposed, emphasizing the need for developing new detection methods for rapid and sensitive identification of biogenic amines, improving bacterial inactivation techniques, and advancing genetic and molecular biology studies to better understand the production mechanisms of these compounds. Furthermore, raising consumer awareness about the health impacts of biogenic amines through educational programs is highlighted as a critical area for public health promotion. In conclusion, the review underscores the importance of biogenic amines in seafood quality and safety. Effective control and prevention measures, combined with ongoing research and regulatory compliance, are essential to minimize health risks associated with these compounds. Ensuring proper handling, storage, and processing conditions, along with increasing consumer awareness, will contribute significantly to managing and mitigating the risks posed by biogenic amines in seafood.

Synergistic Impact of Pomegranate Peel Extract and High Hydrostatic Pressure on Controlling Discolouration and Oxidation in Iberian Dry Sausage Throughout Storage

AbstractThis study aimed to assess the impact of high-pressure processing and the inclusion of a pomegranate peel extract (PPE) on colour, antioxidant residual activities and lipid and protein oxidation of dry-cured and uncured sausages during 120 days of refrigerated storage. Nitrite and PPE were added into the sausage formulations following four treatments: (1) 150 mg/kg NaNO2 (C_Pos), (2) 0 mg/kg NaNO2 (C_Neg), (3) 0 mg/kg NaNO2 + 1% PPE (PPE1) and (4) 0 mg/kg NaNO2 + 2% PPE (PPE2). The four dry sausage batches were divided into two groups, one left untreated (0.1 MPa) and the other subjected to high hydrostatic pressure treatment (600 MPa, 8 min). The results revealed significant differences in the initial oxidation levels, with nitrite removal leading to increased lipid peroxidation and protein carbonylation. The pomegranate extract surpasses nitrite in the amount of residual antioxidant activity in the sausages and was comparable to nitrites in controlling lipid and protein oxidation. Despite this, thiols were affected, decreasing their value in batches with added pomegranate extract. Finally, the colour of the dry sausages varied significantly towards more yellowish and less reddish when the pomegranate extract was added.

Changes of structure properties and potential allergenicity of ovalbumin under high hydrostatic pressures

Egg proteins, notably ovalbumin (OVA), contribute to a prevalent form of food allergy, particularly in children. This study aims to investigate the impact of high hydrostatic pressure (HHP) treatment at varying levels (300, 400, 500, and 600 MPa) on the molecular structure and allergenicity of OVA. The structure of HHP-treated OVA was assessed through fluorescence spectroscopy, circular dichroism spectroscopy, and molecular dynamics (MD) simulation. HHP treatment (600 MPa) altered OVA structures, such as α-helix content decreased from 28.07 % to 19.47 %, and exogenous fluorescence intensity increased by 8.8 times compared to that of the native OVA. The free sulfhydryl groups and zeta potential value were also increased with HHP treatment (600 MPa). ELISA analysis and MD simulation unveiled a noteworthy reduction in the allergenicity of OVA when subjected to 600 MPa for 10 min. Overall, this study suggests that the conformational changes in HHP-treated OVA contribute to its altered allergenicity.

Comparative metabolomic analysis of minced grey mullet (Mugil cephalus) pasteurized by high hydrostatic pressure (HHP) during chilled storage

The beneficial antimicrobial effects of high hydrostatic pressures (HHP) treatments on chill-stored seafood are well documented. Less attention has been given to their impact on the metabolic profile of the seafood, which can offer valuable insights into the preservation mechanisms of these treatments. To address this gap, the present work describes the effects of HHP on the metabolome of chill-stored grey mullet using 1H-NMR. Samples were treated with HHP at 0, 400, 500, and 600 MPa for 10 min and stored at 2–4 °C. HHP effectively inactivated Lactobacillus spp., E. coli, Pseudomonas spp., total Coliforms, and sulfite-reducing anaerobic bacteria (AB), and significantly (p < 0.05) reduced the total mesophilic bacteria (TMB). Additionally, the microbiological shelf-life of grey mullet was extended from 9 to 35 days with the application of 600 MPa HHP. Unsupervised hierarchical cluster analysis and robust Principal Component Analysis (rPCA) revealed the overall changes in metabolites’ profile caused by HHP. HHP treatment significantly reduced the formation rate of decay-related metabolites, including hypoxanthine, trimethylamine (TMA), and biogenic amines, which significantly (p < 0.05) positively correlated with all considered microorganisms. A metabolic pathway analysis revealed several pathways that may underly the spoilage of grey mullet, including tyrosine metabolism, pyruvate metabolism, lysine metabolism, glycolysis/gluconeogenesis, butanoate metabolism, citrate cycle (TCA cycle), phenylalanine metabolism, and sulfur metabolism. Interestingly, among these pathways, lysine metabolism remained unaffected by the considered HHP treatments. These findings provide a better understanding of the mechanisms underlying the effects of HHP on chilled grey mullet.

Nutrient profiles and browning control of wasp larvae

Abstract Entomophagy, the practice of consuming insects, has long been recognized as a sustainable and renewable source of food. This study aimed at assessing the nutritional value of three species of wasp larvae (Provespa barthelemyi, Vespa mandarinia, and V. velutina) and explore effective strategies to address enzymatic browning during processing. The study reveals that wasp larvae exhibit considerable potential as a dietary resource, primarily due to their high protein content, more than 50% of the total dry matter. Remarkably, the presence of vitamin B2 in wasp larvae was unexpectedly high, with an average concentration of 2.20 mg/100 g. Additionally, enzymatic browning process in wasp larvae is closely associated with phenol oxidase (PO) activity. The simultaneous treatment of ascorbic acid at a concentration of 0.2% (w/v) and high hydrostatic pressure at 300 MPa significantly inhibited PO activity. Notably, the combined treatment exhibited a certain degree of efficacy in retaining the taste and texture of the larvae. To the best of our knowledge, this study pioneers the novel combined treatment aimed at mitigating browning in wasp larvae. Overall, our research reveals that wasp larvae boast a wealth of nutritional components, rendering them as a new resource food. Our research also provides an innovative approach for wasp processing.

Design, modeling and optimization of an adhesively bonded ring joint with U-section for ceramic cylindrical pressure hull of deep-sea underwater vehicles

The brittleness of ceramic increases the risk of damage or collapse when the ceramic cylindrical pressure hull is directly connected with a rigid part, especially under high hydrostatic pressure. To solve the above problem, this paper systematically explores the design, modeling and optimization of an adhesively bonded ring joint with U-section (ABRJ-U) to avoid the direct connection of the ceramic hull of a small hadal glider, Petrel, with the hemispherical metal end caps. The ABRJ-U is comprised of a U-shaped metal ring, a gasket, and epoxy adhesive layer. To optimize the design parameters, a mechanical model of ABRJ-U is established. The stress tests prove that the model has better efficiency in optimization, but lowered accuracy compared with regular finite element method. Considering the difficulty of obtaining a more accurate theoretical model, the optimization efficiency of regular finite element method is selected for further improvement by integrating the response surface methodology and multi-objective genetic algorithm. According to the optimization results, our optimization method considers the stress calibration of both the adhesive and gasket, simultaneously achieving a 20.8% reduction in the mass of ABRJ-U. The proposed methods also provide valuable reference for the design, modeling, and optimization of other bonded joints.

Characterization and Biosynthetic Regulation of Isoflavone Genistein in Deep-Sea Actinomycetes Microbacterium sp. B1075.

Deep-sea environments, as relatively unexplored extremes within the Earth's biosphere, exhibit notable distinctions from terrestrial habitats. To thrive in these extreme conditions, deep-sea actinomycetes have evolved unique biochemical metabolisms and physiological capabilities to ensure their survival in this niche. In this study, five actinomycetes strains were isolated and identified from the Mariana Trench via the culture-dependent method and 16S rRNA sequencing approach. The antimicrobial activity of Microbacterium sp. B1075 was found to be the most potent, and therefore, it was selected as the target strain. Molecular networking analysis via the Global Natural Products Social Molecular Networking (GNPS) platform identified 25 flavonoid compounds as flavonoid secondary metabolites. Among these, genistein was purified and identified as a bioactive compound with significant antibacterial activity. The complete synthesis pathway for genistein was proposed within strain B1075 based on whole-genome sequencing data, with the key gene being CHS (encoding chalcone synthase). The expression of the gene CHS was significantly regulated by high hydrostatic pressure, with a consequent impact on the production of flavonoid compounds in strain B1075, revealing the relationship between actinomycetes' synthesis of flavonoid-like secondary metabolites and their adaptation to high-pressure environments at the molecular level. These results not only expand our understanding of deep-sea microorganisms but also hold promise for providing valuable insights into the development of novel pharmaceuticals in the field of biopharmaceuticals.

A comprehensive review on novel synthetic foods: Potential risk factors, detection strategies, and processing technologies

AbstractNowadays, the food industry is facing challenges due to the simultaneous rise in global warming, population, and food consumption. As the integration of synthetic biology and food science, novel synthetic foods have obtained high attention to address these issues. However, these novel foods may cause potential risks related to human health. Four types of novel synthetic foods, including plant‐based foods, cultured meat, fermented foods, and microalgae‐based foods, were reviewed in the study. The original food sources, consumer acceptance, advantages and disadvantages of these foods were discussed. Furthermore, potential risk factors, such as nutritional, biological, and chemical risk factors, associated with these foods were described and analyzed. Additionally, the current detection methods (e.g., enzyme‐linked immunosorbent assay, biosensors, chromatography, polymerase chain reaction, isothermal amplification, and microfluidic technology) and processing technologies (e.g., microwave treatment, ohmic heating, steam explosion, high hydrostatic pressure, ultrasound, cold plasma, and supercritical carbon dioxide) were reviewed and discussed critically. Nonetheless, it is crucial to continue innovating and developing new detection and processing technologies to effectively evaluate these novel synthetic foods and ensure their safety. Finally, approaches to enhance the quality of these foods were briefly presented. It will provide insights into the development and management of novel synthetic foods for food industry.

Urea potentiates the denaturation of bovine serum albumin induced by high hydrostatic pressure

Urea potentiates the denaturation of bovine serum albumin induced by high hydrostatic pressure

Influence of high hydrostatic pressure treatment on the soluble dietary fiber content and physicochemical characteristics of edamame

We used non-thermal high hydrostatic pressure (HHP) technology to process edamame to increase the soluble dietary fiber content of the product. We also comprehensively explored the impact of HHP on the functional properties and fiber structure of edamame. Edamame was treated at a high pressure of 600 MPa for 5-, 10-, and 15-min. Edamame treated with HHP exhibited elevated water-holding, oil-holding, and water-swelling capacities, which were attributed to alterations in the fiber structure. Scanning electron microscopy, used to assess the porous characteristics of the surface, revealed gaps that could retain liquid. This structural modification facilitated enhanced invitro performance in cholesterol adsorption and bile acid-binding force tests. X-ray diffraction analysis revealed that the broken fibers strengthened the (101) crystal plane of fiber crystal I; the reduction in crystallinity caused the fibers to form a loose structure under thermal stability, which increased the water retention and swelling properties. HHP destroyed part of the fiber structure, contributing to the altered functional properties. The findings indicate that HHP treatment adds significant value to edamame, making it a promising raw material for developing functional foods and healthcare products.

Insight into the mechanism of high hydrostatic pressure effect on inhibitory efficiency of three natural inhibitors on polyphenol oxidase

The development of natural inhibitors of polyphenol oxidase (PPO) is crucial in the prevention of enzymatic browning in fresh foods. However, few studies have focused on the effect of subsequent sterilization on their inhibition efficiency. This study investigated the influence and mechanism of high hydrostatic pressure (HHP) on the inhibition of PPO by epigallocatechin gallate (EGCG), cyanidin-3-O-glucoside (C3G), and ferulic acid. Results showed that under the conditions of 550 MPa/30 min, the activity of EGCG-PPO decreased to 55.92%, C3G-PPO decreased to 81.80%, whereas the activity of FA-PPO remained stable. Spectroscopic experiments displayed that HHP intensified the secondary structure transformation and fluorescence quenching of PPO. Molecular dynamics simulations revealed that at 550 MPa, the surface interaction between PPO with EGCG or C3G increased, potentially leading to a reduction in their activity. In contrast, FA-PPO demonstrated conformational stability. This study can provide a reference for the future industrial application of natural inhibitors.

Application of pressure homogenization on whole human milk pasteurized by high hydrostatic pressure: Effect on protein aggregates in milk fat globule membrane and skim milk phases

This study explored the impact of homogenization (at pressures of 16, 30, and 45 MPa) on both raw and high hydrostatic pressure (HHP)-treated human milk (HM). It focused on protein compositions and binding forces of soluble and insoluble fractions for both milk fat globule membrane (MFGM) and skim milk. Mild homogenization of HHP-treated milk increased lactoferrin (LF) levels in the insoluble fractions of both MFGM and skim milk, due to insoluble aggregation through hydrophobic interactions. Intense homogenization of HHP-treated milk decreased the LF level in the MFGM fractions due to the LF desorption from the MFGM, which increased LF level in the insoluble skim milk fraction. Homogenized-HHP treated milk showed noticeably higher casein (CN) level at the MFGM compared to homogenized-raw milk, attributed to HHP effect on CN micelles. Overall, the combined use of HHP and shear-homogenization should be avoided as it increased the biological proteins in insoluble fractions.

Review of Underwater Anechoic Coating Technology Under Hydrostatic Pressure

AbstractThe underwater anechoic coating technology, which considers pressure resistance and low-frequency broadband sound absorption, has become a research hotspot in underwater acoustics and has received wide attention to address the increasingly advanced low-frequency sonar detection technology and adapt to the working environment of underwater vehicles in deep submergence. One the one hand, controlling low-frequency sound waves in water is more challenging than in air. On the other hand, in addition to initiating structural deformation, hydrostatic pressure also changes material parameters, both of which have a major effect on the sound absorption performance of the anechoic coating. Therefore, resolving the pressure resistance and acoustic performance of underwater acoustic coatings is difficult. Particularly, a bottleneck problem that must be addressed in this field is the acoustic structure design with low-frequency broadband sound absorption under high hydrostatic pressure. Based on the influence of hydrostatic pressure on underwater anechoic coatings, the research status of underwater acoustic structures under hydrostatic pressure from the aspects of sound absorption mechanisms, analysis methods, and structural designs is reviewed in this paper. Finally, the challenges and research trends encountered by underwater anechoic coating technology under hydrostatic pressure are summarized, providing a reference for the design and research of low-frequency broadband anechoic coating.

Decoding the Effects of High Hydrostatic Pressure and High-Temperature Short-Time Sterilization on the Volatile Aroma Profile of Red Raspberry Juice.

The loss of distinctive aromas due to sterilization significantly hinders efforts to enhance the sensory quality of fruit and vegetable juices. This study aimed to elucidate the impacts of high-hydrostatic pressure (HHP) and high-temperature short-time (HTST) sterilization methods on the loss of C6 aldehyde aroma-active compounds in red raspberry juice. External standard quantification and quantitative descriptive analysis (QDA) revealed a notable decline in the levels of hexanal and (Z)-3-hexenal following the HHP and HTST treatments (p < 0.05), resulting in a marked attenuation of the grassy aroma characteristic of red raspberry juice. Furthermore, a comprehensive examination of the precursors, pivotal enzymes, intermediates, and downstream aromas within the fatty acid metabolism pathway in different raspberry juice samples indicated that the C6 aldehydes loss induced by HHP and HTST sterilizations was primarily ascribed to the competitive inhibition of β-oxidation and the hindered enzymatic oxidation of fatty acids. These insights suggest that modifying sterilization protocols and enhancing enzymatic stability may help preserve the aroma integrity of raspberry juice. Our findings offer practical guidance for optimizing juice processing techniques to maintain flavor.