Ultra-high Pressure Treatment Research Articles

Ultra-high pressure treatment improve the content of characteristic aromatic components of melon juice from the view of physical changes

IntroductionThe effectiveness of ultra-high pressure (UHP) technology in retaining the flavor of fresh fruit and vegetable juices has been acknowledged in recent years. Along with previously hypothesized conclusions, the improvement in melon juice flavor may be linked to the reduction of its surface tension through UHP.MethodsIn this paper, the particle size, free-water percentage, and related thermodynamic parameters of melon juice were evaluated in a physical point for a deeper insight.ResultsThe results showed that the UHP treatment of P2-2 (200 MPa for 20 min) raised the free water percentage by 7,000 times than the other treatments and both the melting enthalpy, binding constant and Gibbs free energy of P2-2 were minimized. This significantly increased the volatility of characteristic aromatic compounds in melon juice, resulting in a 1.2-5 times increase in the content of aromatic compounds in the gas phase of the P2-2 group compared to fresh melon juice.

Integrated ultra-high pressure and salt addition to improve the in vitro digestibility of myofibrillar proteins from scallop mantle (Patinopecten yessoensis)

Myofibrillar protein (MP) is susceptible to the effect of ionic strength and ultra-high pressure (UHP) treatment, respectively. However, the impact of UHP combined with ionic strength on the structure and in vitro digestibility of MP from scallop mantle (Patinopecten yessoensis) is not yet clear. Therefore, it is particularly important to analyze the structural properties and enhance the in vitro digestibility of MP by NaCl and UHP treatment. The findings demonstrated that as ionic strength increased, the α-helix and β-sheet gradually transformed into β-turn and random coil. The decrease of endogenous fluorescence intensity indicated the formation of a more stable tertiary structure. Additionally, the exposure of internal sulfhydryl groups increased the amount of total sulfhydryl content, and reactive sulfhydryl groups gradually transformed into disulfide bonds. Moreover, it reduces aggregation through increased solubility, decreased turbidity, particle sizes, and a relatively dense and uniform microstructure. When MP from the scallop mantle was treated with 0.5 mol/L ionic strength and 200 MPa UHP treatment, it had the highest solubility (90.75 ± 0.13%) and the lowest turbidity (0.41 ± 0.03). The scallop mantle MP with NaCl of 0.3 mol/L and UHP treatment had optimal in vitro digestibility (95.14 ± 2.01%). The findings may offer a fresh perspectives for developing functional foods for patients with dyspepsia and a theoretical foundation for the comprehensive utilization of scallop mantle by-products with low concentrations of NaCl.

Process optimization of ultra-high pressure treatment of grapes: Effects on the phenolic composition of red wine grapes from the Hexi Corridor region (China)

This research evaluated the impact of ultra-high pressure (UHP) treatment on the phenolic compounds in red wine grapes. Grapes were subjected to varied conditions—specifically differences in applied pressure, pressure holding time and temperature—to ascertain the most effective treatment parameters. Optimal conditions were identified as an applied pressure of 407 MPa, a holding time of 25 min, and a holding temperature of 26 °C. UHP treatment noticeably disrupted the cell structure and diminished PPO activity in the processed samples. The impact of optimal UHP treatment on Cabernet Sauvignon and Merlot's physicochemical indices and phenolic contents was investigated using multivariate statistical analysis. Results highlighted that UHP treatment significantly increased phenolic compounds. Among these, anthocyanins, flavonols, flavanols and stilbenes showed the most pronounced increase. Furthermore, the Cabernet Sauvignon samples responded more favorably to UHP treatment than the Merlot samples.

Enhancing the Gelation Behavior of Transglutaminase-Induced Soy Protein Isolate(SPI) through Ultrasound-Assisted Extraction.

Gelation, as an important functional property of soy protein isolate (SPI), can be improved by some green technologies in food manufacturing, including ultrasound, ultrahigh pressure and microwave treatments. This work investigated the effect of an alkaline solubilisation step in SPI extraction combined with sonication on protein properties. The TGase-induced gel of the modified SPI was prepared to explore the effect of ultrasound on gel properties, including structures, strength, water-holding capacity and rheological properties. Additionally, the differences between traditional ultrasound modification of SPI and current modification methods were analyzed. The results showed that the ultrasonication-assisted extraction method could result in a significant increase in extraction rate from 24.68% to 42.25%. Moreover, ultrasound-assisted modification of SPI gels induced with transglutaminase (TGase) exhibited significant improvement in mechanical properties, such as texture, water-holding capacity and rheological properties, In particular, SPI extracted at 400 W ultrasound intensity for 180 s showed the best overall performance in terms of gel properties. Our method efficiently uniformizes gel structure, enhancing mechanical properties compared to conventional ultrasound methods, which reduced energy consumption and costs. These findings provide insights into the production of high-gelation SPI in food manufacturing.

Chemical characterization and sensory properties of apple brandies aged with different toasted oak chips and ultra-high-pressure treatments

Aging is an important processing step of producing high quality apple brandy. In this study, apple brandies aged by traditional method and using three different toasted oak chips combined with or without ultra-high-pressure (UHP) treatment were prepared to compare their differences in chemical characterization and sensory properties. The results indicated that the brandies aged with toasted oak chip increased the levels of total acidity, volatile acidity and phenolic compounds. It also had the desirable color and taste. The brandy aged with toasted oak chip combined with UHP reached the highest levels of total acidity (1.06 g/L), total phenolic content (284.92 mg/L) and aromatic esters (49.37 %). Therefore, the aging with high toasted oak chip combined with UHP treatment could cut the traditional aging time to meet the same quality as traditional aging method. The results are very useful to develop a fast and efficient aging technique for brandy production.

Screening and molecular dynamics simulation of ACE inhibitory tripeptides derived from milk fermented with Lactobacillus delbrueckii QS306.

Peptides in milk fermented with Lactobacillus delbrueckii QS306 before and after ultrahigh pressure treatment were identified using proteomics. Subsequently, 16 stable tripeptides were screened out based on activity score prediction, PeptideCutter analysis, and hydrophobicity calculations. Among them, WRP, WSR, and YRP showed the best angiotensin-converting enzyme (ACE) inhibitory activity, and their semi-inhibitory concentrations were 46.707, 300.121, and 89.555 μM, respectively. WRP and WSR were competitive inhibitors, whereas YRP was non-competitive. Gastrointestinal simulation revealed that WRP and YRP had better gastrointestinal stability. The values of RMSD, ΔGbind, ΔGpol, and RSMF obtained from molecular dynamics simulation indicated that the interaction of WRP and ACE was stable. Thus, Lactobacillus delbrueckii QS306-fermented milk can serve as an important source of ACE inhibitory peptides both before and after ultrahigh pressure treatment. The strategy of in silico screening, activity evaluation, and molecular dynamics simulation adopted in this study can be applied to the large-scale screening of novel peptides with high ACE inhibitory activity.

Effects of Protein Structure Changes on Texture of Scallop Adductor Muscles under Ultra-High Pressure

In order to investigate the effect of protein structure changes on the texture of scallop adductor muscles under ultra-high pressure, the protein structure, hardness, elasticity, cohesion, and chewing properties of untreated scallops maintained at 200 MPa for 60 s, 120 s, and 180 s were measured and compared. At the same time, sensory indicators were evaluated to verify the effect of ultra-high pressure treatment on the quality of scallop adductor muscles. The results indicated that the mass fraction of the α-helix was decreased by 13.70% and the mass fraction of β–folding was 2.72 times higher in the adductor muscle of scallops compared to the fresh adducts without ultra-high pressure treatment, maintained for 180 s at an ultra-high pressure of 200 MPa. At the same time, the value of I850/I830 of protein tyrosine residues was 1.094, which weakened the water retention ability of the protein, the elasticity of the scallop adduct was reduced from the original 7.16 N to 6.17 N, the cohesion was reduced by 3.76%, and the hardness was increased by 17.45%. This improved the cooking quality of scallops, which was consistent with the sensory evaluation results. Therefore, under ultra-high pressure treatment, changes in the protein structure of the adductor muscle of scallops had a certain impact on their texture, which was able to provide support for in-depth research on the mechanism of ultra-high pressure action.

Ultra-high pressure improved gelation and digestive properties of Tai Lake whitebait myofibrillar protein

This study investigated the effects of ultra-high pressure (UHP) at different levels on the physicochemical properties, gelling properties, and in vitro digestion characteristics of myofibrillar protein (MP) in Tai Lake whitebait. The α-helix gradually unfolded and transformed into β-sheet as the pressure increased from 0 to 400 MPa. In addition, the elastic modulus (G') and viscous modulus (G'') of the 400 MPa-treated MP samples increased by 4.8 and 3.8 times, respectively, compared with the control group. The gel properties of the MP also increased significantly after UHP treatment, e.g., the gel strength increased by a 4.8-fold when the pressure reached 400 Mpa, compared with the control group. The results of in vitro simulated digestion showed that the 400 MPa-treated MP gel samples showed a 1.8-fold increase in digestibility and a 69.6 % decrease in digestible particle size compared with the control group.

Improving the gelation and digestive properties of myofibrillar protein in Litopenaeus vannamei by ultra-high pressure

The objective of this study was to investigate the effects of ultra-high pressure (UHP) on the physicochemical properties, gelling properties, and in vitro digestion characteristics of myofibrillar protein (MP) in Litopenaeus vannamei. The pressures were set at 0, 150, 300, 450, and 600 MPa, respectively. The α-helix structure gradually unfolded and transformed into β-sheet structure as the pressure increased from 0 to 600 MPa. Compared with the control group, the content of α-helix structure of the 600 MPa-treated MP samples decreased by 51.31%, and the content of β-sheet structure increased by a 1.34-fold. In addition, the UHP treatment enhanced the rheological properties of MP. The elastic modulus (G′) and viscous modulus (G″) of the 600 MPa-treated MP samples increased by 4.77-fold and 3.78-fold, respectively, compared with the control group (at frequencies up to 10 Hz). The gel properties of the MP also increased significantly after UHP treatment, e.g., the WHC of MP gel increased by 45.49% and the gel strength increased by a 5.99-fold when the pressure reached 600 Mpa, compared with the control group. The results of in vitro simulated digestion showed that UHP treatment led to the formation of more easily digestible MP gels. Compared with the control group, the 600 MPa-treated MP gel samples showed a 1.89-fold increase in digestibility and a 66.86% decrease in digestible particle size.

Ultrahigh pressure field: A friendly pathway for regulating the cellular adhesion and migration capacity of collagen

Customized control of the biological response between the material matrix and cells is a crucial aspect in the development of the next generation of collagen materials. This study aims to investigate the effects of ultrahigh pressure treatment on the interaction between collagen and cells by subjecting bovine tendon collagen to different intensities of ultrahigh pressure field. The results indicate that ultrahigh pressure treatment alters the spatial folding of collagen, causing distortion of its triple helical conformation and exposing more free amino groups and hydrophobic regions. As a result, collagen's cell adhesion capability and ability to promote cell migration are significantly enhanced. Optimal cell adhesion and migration capabilities are observed in collagen samples treated at 500 MPa for 15 min. However, further increasing the intensity of the ultrahigh pressure treatment leads to severe damage to the triple-helical structure of collagen, along with re-aggregation of free amino groups and hydrophobic moieties, thereby reducing collagen's cell adhesion capability and ability to promote cell migration. Therefore, ultrahigh pressure treatment offers a promising method to effectively regulate collagen-cell adhesion and promote cell migration without the need for external components. This provides a potential means for the customized enhancement of collagen-based material interfaces.

Screening, Characterization, and Mechanistic Evaluation of Angiotensin Converting Enzyme Inhibitory Peptides Derived from Milk Fermented with Lactobacillus delbrueckii QS306 with and without Ultrahigh-Pressure Treatment.

In this study, the peptides in milk fermented with Lactobacillus delbrueckii QS306 with and without ultrahigh-pressure treatment were identified using UPLC-Q-exactive-HF-X-MS/MS. In total, 27 novel pentapeptides with potential angiotensin converting enzyme inhibitory (ACEI) activity were screened via bioinformatic analysis, and the activities of seven novel pentapeptides were assessed. Among them, HLPLP, PYPQR, and VAPFP exhibited better IC50 values. Stability assessment via in vitro simulation revealed that the three pentapeptides were significantly reduced (P < 0.05) during digestion but exhibited 85% activity after digestion. HLPLP was a competitive inhibitor, while PYPQR and VAPFP were noncompetitive inhibitors of ACE. Molecular docking indicated that the three peptides could stably bind to ACE. Molecular dynamics (MD) simulation and activity verification indicated that PYPQR and VAPFP had better stability and activity. This study demonstrated that novel ACEI pentapeptides in milk fermented with L. delbrueckii QS306 with and without ultrahigh-pressure treatment could be considered promising candidates for controlling hypertension.

Changes in quality characteristics based on protein oxidation and microbial action of ultra-high pressure-treated grass carp (Ctenopharyngodon idella) fillets during magnetic field storage

Ultra-high pressure (UHP) and magnetic field (MF) are emerging food preservation technologies, but the research on the effects of combined treatment (UHP-MF) on aquatic products quality is insufficient. Hence, we explored the effects of UHP-MF treatment on the protein properties, microbial action and quality characteristics of stored grass carp fillets. Results showed that 300 MPa UHP treatment combined with MF storage (UHP300-MF) delayed the protein oxidation of stored fillets by inhibiting the accumulation of protein radical and the formation of lipid pro-oxidation products, thus the quality (texture, color) deterioration caused by oxidation was deferred. Additionally, 16S rDNA bacteria flora analysis revealed that UHP300-MF treatment inhibited the flora activity and diversity of fillets, delayed the protein degradation and quality deterioration caused by microbial action. Overall, UHP300-MF treatment suppressed the lipid and protein oxidation as well as microbial action, retarded the quality deterioration, and prolonged the shelf life of stored fillets.

Effects of electron beam irradiation and ultrahigh-pressure treatments on the physicochemical properties, active components, and flavor volatiles of jujube jam

Jujube jam is a high-value product with versatile attributes, capable of undergoing pretreatment to prolong its shelf life while preserving its sensory and nutritional qualities. In this study, electron beam irradiation (EB; 3, 5, and 7 kGy), ultrahigh-pressure (HP; 400, 500, and 600 MPa for 6 min), and conventional thermal pasteurization treatments (PS; 80 °C for 30 min) were evaluated by examining their effects on the physicochemical properties, active components, and flavor volatiles of jujube jam. The results showed that the samples treated with nonthermal technologies significantly outperformed the thermally pasteurized treatments in terms of color (L*, a*, b*, and browning index), bioactive compounds (organic acids, cyclic adenosine monophosphate, and phenolic components), and aroma components. In addition, compared with the untreated samples, EB treatment significantly increased total content of polyphenols by 15.4–26.3% and ABTS+ scavenging activity by 9.5–36.89%. HP treatment (8385.92, 10082.43, and 10032.88 μg/g) significantly increased the acetic acid content in jujube jam compared to the control sample (1940.45 μg/g), and the total content of volatile substance in the HP treated samples was significantly increased by 80.86–134.75%. Therefore, EB and HP are promising treatments for enhancing the nutritional and sensory qualities of jujube jam.

Synergistic effect of ultrahigh pressure and allicin on gel properties, flavor characteristics, and myosin structure of the obturator muscle of the scallop (Patinopecten yessoensis).

The synergistic effects of the combination of ultrahigh pressure (UHP) with allicin on the gel properties, flavor characteristics, and myosin structure of scallops were investigated. The results indicated that chewiness reached maximum, uniform, and dense microstructures at B-300MPa, and scallops with favorable gel properties. In addition, the electronic nose and tongue could clearly distinguish the olfactory and gustatory properties of scallops, and the interaction of UHP and allicin increased the variety of volatile compounds in scallops, which mainly included 1-hydroxy-2-propanone, 1-hexenal, 2-butanone-D, and 1-octen-3-ol. The main performance was fruit aroma and a plantlike aroma and mushroomlike odor. UHP and allicin changed the microenvironment of tryptophan residues, and allicin formed larger aggregates by forming disulfides with myosin. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis results could show that myosin had low degradation in B-300MPa. Thus, comprehensively viewed, UHP and allicin play a role in gel formation of myosin from obturator muscle at 300MPa, whereas allicin and myosin form disulfides as the main factor of myosin gelation. PRACTICAL APPLICATION: To enhance the diversity of scallop preparation methods and improve the quality of the obtained product, UHP and allicin treatment result in scallops with satisfactory chewiness and flavor, which provides application prospects for scallop processing.

Structural characterization and antioxidant activity of polysaccharides extracted from Porphyra haitanensis by different methods

This study was to investigate the structure and antioxidant activity of Porphyra haitanensis polysaccharides (PHPs) extracted by different methods, including water extraction (PHP), ultra-high pressure (UHP-PHP), ultrasonic (US-PHP) and microwave assisted water extraction (M-PHP). Compared with water extraction, the total sugar, sulfate and uronic acid contents of PHPs was enhanced by ultra-high pressure, ultrasonic and microwave assisted treatments, especially those of UHP-PHP were increased by 24.35 %, 12.84 % and 27.51 %, respectively (p < 0.05). Meanwhile, these assisted treatments affected the monosaccharide ratio of polysaccharides and significantly reduced the protein content, molecular weight as well as particle size of PHPs (p < 0.05), and resulted in a loose microstructure with more porosity and fragments. PHP, UHP-PHP, US-PHP, and M-PHP all possessed in vitro antioxidant capacity. Among them, UHP-PHP had the strongest oxygen radical absorbance capacity, DPPH and ·OH radicals scavenging capacities, which increased by 48.46 %, 116.24 %, and 14.98 % respectively. Moreover, PHPs particularly UHP-PHP effectively increased the cell viability and reduced ROS levels of H2O2 induced RAW264.7 cells (p < 0.05), indicating their good effects against cell oxidative damage. The findings suggested that PHPs with ultra-high pressure assisted treatments has the better potential to develop natural antioxidant.

Effect of ultrahigh-pressure treatment on the structure and allergenicity of peach allergenic proteins

Peach is a common plant-derived allergenic food and ultrahigh-pressure treatment is often used in peach products. In our study, an in-depth analysis of the structural and allergenicity changes of peach allergenic proteins after UHP treatment was performed by spectroscopy, mass spectrometry combined with serology and cytology. The results indicated that UHP treatment could reduce the content of peach soluble proteins and cause changes in secondary and tertiary structures. In addition, more hydrophobic residues were exposed and proteins tended to polymerize after UHP-treatment. The results of immunological assays showed that UHP treatment could reduce the IgE binding capacity of peach proteins and affect the ability of basophil degranulation, the upregulation of some cytokines may contribute to the reduction of peach protein allergenicity. Notably, UHP treatment may lead to the masking of some digestion sites in Pru p 3 epitopes, thus impeding human digestion and increasing the potential risk of allergenicity.

Contribution of process-induced molten-globule state formation in duck liver protein to the enhanced binding ability of (E,E)-2,4-heptadienal.

Extracted proteins of alternative animal origin tend to present strong off-flavor perception due to physicochemical interactions of coextracted off-flavor compounds with proteins. To investigate the relationship between absorption behaviors of volatile aromas and the processes-induced variations in protein microstructures and molecular conformations, duck liver protein isolate (DLp) was subjected to heating (65/100 °C, 15 min) and ultra-high pressure (UHP, 100-500 MPa/10 min, 28 °C) treatments to obtain differential unfolded protein states. Heat and UHP treatments induced the unfolding of DLp to varied degrees, as revealed by fluorescence spectroscopy, ultraviolet-visible absorption, circular dichroism spectra and surface hydrophobicity measurements. Two types of heating-denatured states with varied unfolding degrees were obtained, while UHP at both levels of 100/500 MPa caused partial unfolding of DLp and the presence of a molten-globule state, which significantly enhanced the binding affinity between DLp and (E,E)-2,4-heptadienal. In particular, significantly modified secondary structures of DLp were observed in heating-denatured samples. Excessive denaturing and unfolding degrees resulted in no significant changes in the absorption behavior of the volatile ligand, as characterized by observations of fluorescence quenching and analysis of headspace concentrations. Defining process-induced conformational transition behavior of matrix proteins could be a promising strategy to regulate food flavor attributes and, particularly, to produce DLp coextracted with limited off-flavor components by modifying their interaction during extraction processes. © 2023 Society of Chemical Industry.

Effects of Ultra-High Pressure Synergistic Enzymatic Hydrolysis on Flavor of Stropharia rugoso-annulata

In this study, using gas chromatography-mass spectrometry (HS-SPME-GC-MS), electronic nose (E-nose), high performance liquid chromatography (HPLC), and electronic tongue (E-tongue) to analyze the effect of ultra-high pressure (UHP) synergistic enzymatic hydrolysis on the flavor compounds of enzymatic hydrolysates of S. rugoso-annulata. The results demonstrated that 38 volatile flavor substances were identified in the enzymatic hydrolysates of S. rugoso-annulata treated at atmospheric pressure and 100, 200, 300, 400, and 500 MPa, mainly 6 esters, 4 aldehydes, 10 alcohols, 5 acids, and 13 other volatile flavor substances, and the most kinds of flavor substances reached 32 kinds when the pressure was 400 MPa. E-nose can effectively distinguish the overall changes of enzymatic hydrolysates of S. rugoso-annulata treated with atmospheric pressure and different pressures. There was 1.09 times more umami amino acids in the enzymatic hydrolysates at 400 MPa than in the atmospheric pressure enzymatic hydrolysates and 1.11 times more sweet amino acids at 500 MPa than in the atmospheric pressure enzymatic hydrolysates. The results of the E-tongue indicate that the UHP treatment increased umami and sweetness and reduced bitterness, which was also confirmed by the results of amino acid and 5'-nucleotide analysis. In conclusion, the UHP synergistic enzymatic hydrolysis can effectively improve the overall flavor of the enzymatic hydrolysates of S. rugoso-annulata; this study also lays the theoretical foundation for the deep processing and comprehensive utilization of S. rugoso-annulata.

Effect of ultra-high pressure treatment on structural and functional properties of dietary fiber from pomelo fruitlets

The effects of ultra-high pressure treatment on structural and functional properties of dietary fiber from pomelo fruitlets were analyzed. The results showed that ultra-high treatment changed monosaccharide composition, increased total dietary fiber and soluble dietary fiber from pomelo fruitlets, especially at 400 MPa where soluble dietary fiber was greatly increased from 32.49% ± 0.23% to 41.92% ± 0.32% as compared to native one (p < 0.05). Besides, ultra-high pressure treatment enhanced water- and oil-holding capacity, as well as swelling capacity of dietary fiber, which were related to its more porous structure and hydrophobic groups. Crystallinity and thermal stability of ultra-high pressure modified dietary fibers increased. Moreover, ultra-high pressure modified dietary fibers possessed stronger bile acid binding and pancreatic lipase inhibition capacities, suggesting its better potential in vitro hypolipidemic activity. Our findings suggested that ultra-high pressure treatment is a promising method to obtain dietary fiber with excellent functional properties, and can provide a basis for the high-value utilization of pomelo fruitlets as functional food with blood-lipid regulation.

Effects of different cold sterilization techniques on physicochemical and flavor quality of low salt sliced bacon

The effects of irradiation, ultrahigh pressure and ultraviolet combined coating (UV-coating) on physicochemical, microbial, sensory and volatile flavor compounds of low salt sliced bacon under their optimal sterilization conditions were investigated to explore the most suitable treatment for this product. The results indicated that the sterilization effect of irradiation and ultrahigh pressure was better than that of UV-coating treatment, and the nitrite content of the three treatments was far lower than the Chinese standard limit. The effect of irradiation treatment on the structure of sliced bacon was considered to be the lowest, but it promoted fat oxidation and the formation of sulfur compounds, which in turn affected the flavor. The ultrahigh pressure treatment could improve the water-holding capability and taste feeling, meanwhile remain the color as well as the composition and relative content of the main aromatic compounds such as aldehydes, phenols and hydrocarbons closest to blank group. UV-coating treatment could significantly increase moisture content, block oxygen and raise color, while its sterilization effect was poor and the sour was heavier, easily to affect the edible quality of the product. Therefore, the ultrahigh pressure process was considered as the best according to the sterilization ability and flavor quality.