High-pressure Homogenization Treatment Research Articles

Advancing soy protein isolate-ulvan film physicochemical properties and antioxidant activities through strategic high-pressure homogenization technique

Soy protein-based films often exhibit poor properties, including limited mechanical strength, stability, and bioactivity, which hinder their extensive application in the food industry, particularly in edible packaging. To enhance the properties of soy protein-based films, we employed high-pressure homogenization (HPH) to modify the soybean protein isolate (SPI) molecules and sought to cross-link SPI with ulvan polysaccharide, which possesses distinctive bioactivities. The results confirmed that soluble ulvan polysaccharides were incorporated into the cross-linking system through hydrogen bonding. Results indicated that HPH treatment enhanced SPI's solubility and surface hydrophobicity (H0), promoting hydrogen bonding and hydrophobic interactions between SPI and ulvan, as evidenced by ζ-potential and turbidity measurements. Structural and microstructural analyses of both individual SPI and composite films, using FT-IR, XRD, CD and SEM, demonstrated a high compatibility between HPH-treated SPI and ulvan. The incorporation of ulvan reduced the films' tensile strength (TS), but higher pressure significantly improved it (p < 0.05). Post-HPH modification, the films exhibited increased contact angle and swelling capacity (p < 0.05), indicating enhanced hydrophobicity. Higher pressure treatments resulted in more opaque and yellowish films, thereby diminishing ultraviolet light transmission. Thermal stability analyses, via TGA-DSC, showed that U-HSPI films had improved thermal stability compared to pure SPI films. Moreover, ulvan inclusion boosted the antioxidant capacity of SPI films, especially after HPH treatment. Overall, this study confirms that HPH modification substantially influences the properties and activities of SPI-based films, and the complex films based on SPI and ulvan with improved physicochemical and antioxidant properties exhibit a great potential in the food packaging field.

Enhancing Cutin Extraction Efficiency from Industrially Derived Tomato Processing Residues by High-Pressure Homogenization.

This study primarily aimed to enhance the extraction of cutin from industrial tomato peel residues. Initially, the conventional extraction process was optimized using response surface methodology (RSM). Subsequently, high-pressure homogenization (HPH) was introduced to improve extraction efficiency and sustainability. The optimization process focused on determining the optimal conditions for conventional extraction via chemical hydrolysis, including temperature (100-130 °C), time (15-120 min), and NaOH concentration (1-3%). The optimized conditions, determined as 130 °C, 120 min, and 3% NaOH solution, yielded a maximum cutin extraction of 32.5%. Furthermore, the results indicated that applying HPH pre-treatment to tomato peels before alkaline hydrolysis significantly increased the cutin extraction yield, reaching 46.1%. This represents an approximately 42% increase compared to the conventional process. Importantly, HPH pre-treatment enabled cutin extraction under milder conditions using a 2% NaOH solution, reducing NaOH usage by 33%, while still achieving a substantial cutin yield of 45.6%. FT-IR analysis confirmed that cutin obtained via both conventional and HPH-assisted extraction exhibited similar chemical structures, indicating that the main chemical groups and structure of cutin remained unaltered by HPH treatment. Furthermore, cutin extracts from both conventional and HPH-assisted extraction demonstrated thermal stability up to approximately 200 °C, with less than 5% weight loss according to TGA analysis. These findings underscore the potential of HPH technology to significantly enhance cutin extraction yield from tomato peel residues while utilizing milder chemical hydrolysis conditions, thereby promoting a more sustainable and efficient cutin extraction process.

Insight into the mechanism of synergy of ultrasound and high pressure homogenization on the emulsion stability and interfacial behaviors of α-lactalbumin with mogroside V

Due to uneven distribution amino acid residues of α-lactalbumin (αLA) at oil-water interface, some measurement should be adopted to improve its interfacial behavior and emulsion stability. Therefore, this study focused on the mechanism of synergy of ultrasound and high pressure homogenization on the emulsion stability and interfacial behaviors of α-lactalbumin with mogroside V (MGV). Four treatments were adopted: ultrasound (US), high pressure homogenization (HPH) and combined treatment (US-HPH and HPH-US). Primarily, emulsion stability of αLA/MGV was analyzed. US-HPH or HPH-US exhibited better emulsion stability than US or HPH. Especially, HPH-US-αLA/MGV emulsion was not stratified at the given time (45 d), which was the most stable emulsion. Moreover, the micromorphology of emulsion showed that MGV and UH/HPH treatment suppressed the aggregation of αLA emulsion droplet. In addition, interfacial adsorption mass and viscoelasticity of physical treated αLA was improved with MGV in the order of HPH-US > US-HPH > US > HPH, specifically, frequency shift (ΔF) and dissipation shift (ΔD) of HPH-US-αLA/MGV was 42.2% and 32.5% higher than that without MGV. This finding may provide a potential approach for obtaining natural and high-efficient protein-based emulsifier in food industry.

Development and characterization of pH-sensing films based on red pitaya (Hylocereus polyrhizus) peel treated by high-pressure homogenization for monitoring fish freshness

High pressure homogenization (HPH) was used to physically modify red pitaya (Hylocereus polyrhizus) peel (RPP) dispersions to develop pH-sensing films for monitoring fish freshness. Effects of HPH treatment at various pressures of 0 (control), 10, 20, 30, 40, 60 and 80 MPa on microstructure and properties of RPP film-forming dispersions (FFDs) and their resultant films were systematically investigated. Results showed that due to the structure destructing effect of HPH, the mean particle size of RPP dispersion treated at 80 MPa decreased significantly from 129.17 to 37.41 μm and its total soluble solids content increased from 7.64 to 8.62 °Bx. Rheological analysis manifested that all FFDs exhibited a shear thinning behavior with higher apparent viscosities as well as storage modulus and loss modulus with increasing HPH pressure. Besides, the HPH treated FFDs had a higher total betacyanins content and showed an obvious color response to pH variation. Consequently, the resultant films had not only smoother surfaces and more transparent appearance, but also better water vapor barrier and mechanical properties than the control. Particularly, film obtained from RPP treated at 60 MPa showed a highest tensile strength of 21.87 MPa and elongation at break of 22.09%, together with a lowest water vapor permeability of 11.41 g⋅mm⋅m−2⋅d−1⋅kPa−1. Notably, this film also exhibited high sensitivity to volatile ammonia and showed a remarkable color variation when applied for monitoring fish spoilage at 25 °C. Thus, the pH-sensing films developed from HPH treated RPP had desirable properties to be potentially used in intelligent food packaging.

Physicochemical and rheological properties of soybean oil body fermented milk: Impacts of high pressure homogenization

In the present research, the impacts of high-pressure homogenization (HPH) (20, 60, 90, 120 and 150 MPa) on the physicochemical, rheological and sensory properties of soybean oil body (SOB) fermented milks were explored. Experimental results showed that with the increase of HPH pressure, acidity and water-holding capacity (WHC) of SOB fermented milk significantly increased, while its pH, peroxide value (PV) and thiobarbituric acid reactive substances (TBARS) significantly decreased. The SOB fermented milk was found to be pseudoplastic fluids and the SOB fermented milk at 150 MPa had the highest apparent viscosity. Meanwhile, the SOB fermented milk of 150 MPa possessed the highest sensory score. Finally, principal component analysis (PCA) and heatmap showed that SOB fermented milk had the best characteristics after HPH treatment at 150 MPa. Therefore, HPH pressure could observably improve sensory, textural and rheological properties of SOB fermented milk. These results provide theoretical reference for HPH treatment to develop high-quality fermented dairy products.

Effects of high-pressure homogenization and ultrasound on the composition, structure, and physicochemical properties of proteins extracted from Nannochloropsis Oceania

This study examined the effects of high-pressure homogenization (HPH) and ultrasonication pre-treatment on the structural and physicochemical properties of proteins extracted from defatted Nannochloropsis Oceania biomass (DNOB). HPH treatment was found to enhance the solubility of protein extracted from DNOB compared to ultrasound, where samples pretreated with three passes (3P) of HPH exhibited lower solubility than two passes (2P). The morphology of extracted samples was visualized by scanning electron microscopy, which HPH pre-treatment, especially with more passes, were able to breakdown DNOB into fragments. Alternatively, more holes were displayed on the surface of the extracts pretreated with ultrasound especially when higher amplitude applied. The particle size of extracts from HPH3P (129.5 µm) significant dropped from HPH2P (314.25 µm), where samples pretreated with ultrasound at 20 % amplitude (US20) also decreased in particle size compared to 40 % amplitude (US40), from 115.25 µm to 78.22 µm. Protein flexibility of DNOB extracts were enhanced by both HPH2P and HPH3P but decreased for ultrasound samples. β-sheets were found to be the most abundant protein secondary structure for all samples, where samples treated with HPH3P contained the highest percentage of β-sheets (72 %) than control, HPH2P, ultrasonication at 20 and 40 % amplitude (52–62 %). The high percentage of β-sheets found in HPH3P sample also contributed to its outstanding emulsifying properties which stood out among all, especially at concentrations over 1 mg/ml. Results obtained from this study helped to direct the application of DNOB extracts as functional food ingredient for future food innovation.

Phytochemical composition and in-vitro bioaccessibility of phenolics in different varieties of tamarillo (Solanum betaceum) fruits: Effect of the high-pressure homogenization and ultrasonication

The phytochemical composition in three different varieties of tamarillo (yellow, red, and purple) cultivated in Northeast India was analysed. The pulp showed good amount of protein, fat, and crude fiber, and the pH and TSS of the tamarillos ranged from 3.70 to 3.94 and 9.6–10.2 °Brix, respectively. Vitamin C was highest in purple tamarillo and all were rich in potassium. Anthocyanins were majorly found in purple tamarillo (0.35 mg C3G/g), while carotenoids were maximum in yellow tamarillo (0.63 mg βCE/100 g). However, both anthocyanins and carotenoids pigments were found in purple and red tamarillo varieties. Through HPLC analyses, six phenolic acids were identified and among them, gallic, chlorogenic, ferulic and rosmarinic acids were the major ones. Pelargonidin-3-O-rutinoside was the major anthocyanin in purple (86.22 µg/g) and red (9.88 µg/g) tamarillo. Three different carotenoids viz. zeaxanthin, β-cryptoxanthin and β-carotene were present in all the varieties of tamarillo. High pressure homogenization and ultrasonication treatments had significant impact on the phytochemical composition. High pressure homogenization at 750 bar and ultrasound for 10 min showed higher phenolics, anthocyanins and carotenoids in the tamarillo varieties and these techniques are recommended for processing of tamarillos. The treated pulp rich in phytochemicals can be used for novel product development.

Tailoring Nanostructured Cellulose for Efficient Pickering Emulsions Stabilization

AbstractNanostructured celluloses, nanofibrils (CNFs) and nanocrystals (CNCs), are prepared through TEMPO‐mediated oxidation by controlling the intensity of the process modulated by catalyst concentration and processing time. These nanomaterials are evaluated as stabilizers for Pickering emulsions, fabricated using high‐pressure homogenization (HPH). Both CNFs and CNCs exhibit efficient steric and electrostatic stabilization of oil‐in‐water (O/W) emulsions. CNFs display strong inter‐droplet interactions, leading to the formation of a 3D fibrous network emulsion with higher viscosity compared to CNCs‐stabilized emulsions. However, CNFs also show a higher tendency toward flocculation, due to fibrils’ entanglement in the continuous phase. Interestingly, the HPH treatment has a notable impact on the CNFs’ interfacial layer, enhancing the emulsifying ability of CNFs and improving stability against coalescence. Conversely, CNCs‐stabilized emulsions exhibit lower viscosity but demonstrate higher interfacial activity and stabilization capability. Remarkably, no phase separation during 10 months of refrigerated storage, indicating excellent long‐term stability. Importantly, the HPH treatment does not significantly change the emulsifying ability of CNCs. In conclusion, this study highlights the possibility of obtaining nanocelluloses (NCs) with tailored emulsifying properties by regulating the intensity of TEMPO‐mediated oxidation applied to pulp cellulose. These findings open up new opportunities for the development of innovative ingredients for the food and cosmetic industries.

Foaming and structural properties of egg yolk components microgel particles and their adsorption characteristics at the air-water interface

In this study, microgel particles of egg yolk and its components were constructed by inducing and modifying their structure via the high-pressure homogenization (HPH). In order to compare their structural characterization and reveal their adsorption mechanism at the air-water interface, yolk components were also combined with egg white protein (EWP) to achieve their microgels for investigation. Results suggested that after HPH, foam stabilities of egg yolk protein microgel (EYM) and egg yolk plasma microgel (EPM) were significantly improved, whereas no significance occurred on egg yolk granules microgel (EGM). Interestingly, after HPH, the adsorption capacity of the microgels from combination of yolk components and EWP exhibited a significant increasing trend. However, their interfacial adsorption stability was poor. Fluorescence spectrum and surface tension revealed that more hydrophilic groups and lower surface tension would occur on EY and EP after HPH, whilst no significant effects would happen on EG, which was consistent with the results of foaming characteristics. SDS-PAGE exhibited that there was no obvious change in the protein bands of egg yolk and its components, indicating that egg yolk and component proteins did not undergo covalent crosslinking or degradation with HPH treatment. In summary, our study prepares for the first time of the microgel particles from egg yolk components for stabilizing the air-water interface. In addition, we have revealed the relationship between the physicochemical properties, microstructures and interfacial adsorption properties of the microgel particles from egg yolk components, and have explored their mechanisms in depth.

Unraveling the effect of combined heat and high-pressure homogenization treatment on the improvement of chickpea protein solubility from the perspectives of colloidal state change and structural characteristic modification

Chickpea protein (CP) is a promising plant protein ingredient, but the poor solubility has limited its broad application. In this study, heating followed by high-pressure homogenization (HPH) was used to improve the solubility of CP. The results showed that combined heat (80℃, 30 min) and HPH (80 MPa, 2 cycles) treatment exhibited an additive effect in improving the solubility of CP. This improvement could be attributed to the dissociation and the rearrangement of large insoluble protein aggregates into small-sized soluble protein aggregates, the increased exposure of hydrophobic residues and reactive sulfhydryl groups, the transformation of α-helices to β-sheets and β-turns. Moreover, the 11S subunits of CP could form reinforced disulfide covalent cross-links under heating + HPH, which may provide steric hindrance preventing the reassembly of large protein bodies. This work proposes an interesting approach to enhance the physicochemical properties of CP for tailoring techno-functional plant protein ingredients in food formulations.

Improving the solubility and interfacial absorption of hempseed protein via a novel high pressure homogenization-assisted pH-shift strategy

A pH shift treatment aided by high pressure homogenization (HPH) with various pressures (0–120 MPa) was employed to structurally modify hempseed protein isolate (HPI). Compared with individual pH shift or HPH treatment, HPH-assisted pH shift improved the structural flexibility of HPI, as revealed by the increased random coil in protein secondary structure. With the incorporation of HPH into pH shift, the intrinsic fluorescence intensity was remarkably attenuated and redshifted, whereas the surface hydrophobicity was pronouncedly boosted, indicating the extensive unfolding of protein structure. Moreover, the cotreated HPI exhibited a smaller and more homogenous particle size, notably at a higher pressure. Consequently, the solubility was drastically raised by the cooperated treatments, to the maximum value (62.8 %) at 120 MPa. These physicochemical changes in the cotreated HPI facilitated a consolidated interfacial activity. Moreover, the cooperated treatment, especially highly pressured (120 MPa), facilitated the penetration and rearrangement of proteins at the oil–water interface.

Characterization of yeast protein isolates extracted via high-pressure homogenization and pH shift: A promising protein source enriched with essential amino acids and branched-chain amino acids.

In the global food industry, plant-based protein isolates are gaining prominence as an alternative to animal-based counterparts. However, their nutritional value often falters due to insufficient essential amino acids. To address this issue, our study introduces a sustainable protein isolate derived from yeast cells, achieved through high-pressure homogenization (HPH) and alkali pH-shifting treatment. Subjected to HPH pressures ranging from 60 to 120MPa and 1 to 10 cycles, higher pressure and cycle numbers resulted in enhanced disruption of yeast cells. Combining HPH with alkali pH-shifting treatment significantly augmented protein extraction. Four cycles of HPH at 100MPa yielded the optimized protein content, resulting in a yeast protein isolate (YPI) with 75.3g protein per 100g powder, including 30.0g of essential amino acids and 18.4g of branched-chain amino acids per 100g protein. YPI exhibited superior water and oil-holding capacities compared to pea protein isolate, whey protein isolate (WPI), and soy protein isolate. Although YPI exhibited lower emulsifying ability than WPI, it excelled in stabilizing protein-stabilized emulsions. For foaming, YPI outperformed others in both foaming ability and stabilizing protein-based foam. In conclusion, YPI surpasses numerous plant-based protein alternatives in essential amino acids and branched-chain amino acids contents, positioning it as an excellent candidate for widespread utilization as a sustainable protein source in the food industry, owing to its exceptional nutritional advantages, as well as emulsifying and foaming properties. PRACTICAL APPLICATION: This study introduces a sustainable protein isolate derived from yeast cells. YPI exhibited considerable promise as a protein source. Nutritionally, YPI notably surpassed plant-based protein isolates in EAA and BCAA contents. Functionally, YPI demonstrated superior water-holding and oil-holding capacities, as well as an effective emulsion and foam stabilizer.

Mechanistic understanding of the improvement of the digestive retention of anthocyanins by modified pectin after high-pressure homogenization of strawberry pulp

The physical property and retention of anthocyanins (ACNs) during digestion of strawberry pulp after high-pressure homogenization (HPH) (20/60/100/140 MPa) were analyzed, and their correlations with the three pectin samples—water-soluble (WSP), chelator-soluble (CSP) and sodium carbonate-soluble (NSP)—were evaluated. Compared to the control, the particle size and apparent viscosity of the pulp decreased, and the retention of total ACNs increased, reaching the highest at 100 MPa, with an increase of 15.41%. After HPH treatment, the alcohol-insoluble residue (AIR) and WSP content increased, while the molecular weight (Mw), and microstructural tightness of the three pectin samples decreased. The homogalacturonan (HG) region of WSP increased, and the degree of methylesterification (DM) of CSP decreased. Furthermore, the important role of the modified pectin in the increased retention of ACNs during digestion was reaffirmed by the binding ratio and retention of ACNs in pectin-ACNs complexes. Industrial relevanceThe effect of HPH treatment on the quality attributes of fruits and vegetable juice attracted a lot of attention. This study confirmed that the modification of pectin in HPH-treated strawberry pulp, which promoted its interaction with ACNs, could effectively enhance the retention of ACNs during digestion. Consequently, this study provides the fundamental theory and technological support for the potential to elevate the nutritional value of fruits and vegetables.

Effects of High-Pressure Homogenization Treatment on the Development of Antioxidant Zanthoxylum bungeanum Leaf Powder Films for Preservation of Fresh-Cut Apple.

This study determined that Zanthoxylum bungeanum leaves (ZBLs) are rich in functional components such as cellulose, protein, flavone, and polyphenols. Therefore, they were used as the main raw material, with sodium alginate as a thickener and glycerol as a plasticizer, to investigate the preparation of active films from ZBL powder through high-pressure homogenization (HPH). The physical, optical, mechanical, and antioxidant properties of the films were evaluated, and their application in preserving fresh-cut apples was examined. The results showed that the optimal concentration of ZBL powder was 1.5% under a 30 MPa HPH treatment. The resulting HPH-treated films exhibited a denser microstructure and improved water vapor barrier properties and mechanical strength. Compared to the films without HPH treatment, the tensile strength increased from 4.61 MPa to 12.13 MPa, the elongation at break increased from 21.25% to 42.86%, the water vapor permeability decreased from 9.9 × 10-9 g/m·s·Pa to 8.0 × 10-9 g/m·s·Pa, and the transparency increased from 25.36% to 38.5%. Compared to the control group, the fresh-cut apples packaged with the HPH-treated ZBL active films exhibited effective preservation of apple quality during a five-day period at 4 °C and 70% humidity, showing better preservation effects than the other groups. In conclusion, the use of HPH treatment in developing novel biopolymer active films from ZBL powders with enhanced properties holds potential for various applications.

Manothermosonication, high-pressure homogenization, and their combinations with pH-shifting improve the techno-functionality and digestibility of hemp protein

The growing interest in plant-based proteins, particularly hemp protein, has driven the exploration of new methods to address the limitations of its industrial utilization, such as its poor functional properties. This study examined how manothermosonication (MTS) and high-pressure homogenization (HPH) techniques, along with pH-shifting, could enhance the techno-functionality of hemp protein isolate (HPI) and produce functionalized hemp protein nanoaggregates. Optimal processing conditions of MTS were 50 °C, 200 kPa, and 90 s, as determined by response surface methodology. The pH-shifting + MTS and pH-shifting + HPH treatments reduced the size of hemp protein nanoaggregates by 3.2- and 1.9-fold, respectively, compared to the untreated HPI. The changes in secondary (FTIR, CD), tertiary (SH group, fluorescence intensity), and 3D structures (XRD) confirmed modifications of treated hemp proteins. The XRD patterns showed an increase in the %crystallinity values from 21% to 29% upon the pH-shifting + MTS treatment. The combination of pH-shifting + MTS resulted in the highest solubility and digestibility, 2.1- and 1.3-fold higher than the untreated HPI, respectively, followed by the MTS-alone and HPH treatments. In addition, the emulsion properties (emulsion activity, stability, creaming index, and droplet sizes) exhibited the highest values in HPI treated by pH-shifting + MTS and + HPH. The MTS and HPH technologies provide a promising viewpoint for producing protein nanoaggregates with enhanced functional properties for microencapsulation, edible film, and other applications.

The impact of pH shifting combined high-pressure homogenization on structural and functional properties of rice dreg protein

The composition and aggregation of rice dreg protein (RDP) have a major impact on its properties. The aim of the present study was to investigate the effects of pH shifting combined high-pressure homogenization (HPH) treatment on functional properties of RDP. The improvement of RDP functional properties with pH shifting at alkaline (pH 12) condition followed by HPH treatment (20, 40, 60, 80, 100 MPa) prior to neutralization at pH 7 was much better than that of HPH and/or pH shifting. The method carried out at under pH 12 followed by HPH 100 MPa was found to be the most efficient treatment for increasing the solubility of RDP from 0.86% to 63.50%, the emulsification from 3.13% to 7.10%, and the foaming capacity from 19.33% to 179.67%. It was revealed that pH shifting combined HPH treatment depolymerized the aggregates, reduced the particle size, spread the structure, decreased the surface hydrophobicity of RDP, and avoided any bitterness production. These results have important implications for the modification of proteins with improved functional profiles.

Structural modification of oat protein by thermosonication combined with high pressure for O/W emulsion and model salad dressing production

Oat protein is becoming an important ingredient in beverages and formulated foods owing to its high nutritive value and bland flavor; yet, its functionality remains largely unexplored. This study sought to enhance the surface activity of oat protein isolate (OPI) through high-intensity ultrasound (HIU; at 20 or 60 °C) combined with high pressure homogenization (HP; 30 MPa) treatments. Sonication disturbed the protein conformation and significantly improved surface hydrophobicity (19.7%) and ζ-potential (15.7%), which were further augmented by subsequent HP (P < 0.05). Confocal microscopy revealed a uniform oil droplet distribution in emulsions prepared with HIU+HP combination treated OPI, and the oil droplet size decreased up to 35.6% when compared to that of non-treated OPI emulsion (d = 1718 nm). Emulsifying activity was greater for HIU+HP than for HIU, and the viscosity followed a similar trend. Moreover, while emulsions prepared with HIU or HP treated OPI were more stable than control, the 60 °C HIU+HP combination treatment yielded the maximum stability. In corroboration, a model salad dressing prepared from HIU+HP treated OPI displayed a homogenous oil droplet distribution and an improved viscosity. Therefore, thermosonication combined with high pressure homogenization may be suitable for salad dressings and other oil-imbedded food products.

High‐pressure‐assisted protein isolation from pumpkin seed press cake

SummaryTraditional solvent‐based approaches for the separation of protein from plant sources are widely used, although they can lead to low protein yield and protein degradation. In this study, protein isolation was conducted by alkaline extraction (AE) and isoelectric precipitation, and the effect of high‐pressure homogenisation (HPH) (0 MPa [control], 50, 100, and 150 MPa) at two different stages during extraction was assessed, namely high pressure homogenisation followed by alkaline extraction (HPH + AE) or alkaline extraction followed by high pressure homogenisation (AE + HPH). Although the control procedure resulted in a protein yield of 45.99 ± 0.72%, the highest protein yield was determined by AE + 100 MPa HPH (61.92 ± 1.06%). Solubility, foaming capacity, emulsification index, hue angle, and denaturation enthalpy of the isolated protein increased after HPH treatments compared to control. Generally, the high‐pressure treatment during protein isolation increased pumpkin seed press cake's protein yield and enhanced the isolates' techno‐functional properties.

Structure, bioavailability and physicochemical properties of icariin-soymilk nanoparticle

Soymilk is a natural nanocarrier. However, the performance of flavonoid-soymilk nano-complex remains unclear. In this work, icariin-soymilk nano-complexes (ISNCs) were successfully fabricated and characterized. The effects of high-pressure homogenization (HPH) treatment on structure and physicochemical properties of soymilk and nano-complexes were investigated. HPH treatment could significantly improve the surface hydrophobicity and interfacial activity of soymilk. The soymilk with HPH treatment could significantly improve the water solubility (20 folds), thermal stability and bioavailability of icariin. The highest encapsulation efficiency (93.28 %), loading capacity (39.09 µg/mg), ζ-potentia (absolute value, 31.20 mV) and bioavailability (72.14 %) were observed in HSI-200 (200 bar of homogenization pressure). While HSI-500 (500 bar of homogenization pressure) showed the smallest particle size (183.73 nm). ISNCs showed a rougher surface and an irregular lamellar structure with large amount of fine particles by using Cryo-SEM, suggesting that icariin was encapsulated in soymilk. These data supplied a novel strategy to improve the performance of icariin in functional foods.

Influence of heat treatment before and/or after high-pressure homogenization on the structure and emulsification properties of soybean protein isolate

This study investigates the effects of heat treatment before high-pressure homogenization (HHPH) and heat treatment after high-pressure homogenization (HPHH) at different pressures (20, 60, and 100 MPa) on the structural and emulsification properties of soy protein isolate (SPI). The results indicate that HHPH treatment increases the surface hydrophobicity (H0) of the SPI, reduces β-fold and irregular curls, leading to the formation of soluble aggregates, increased adsorbed protein content, and subsequent improvements in emulsification activity index (EAI) and emulsion stability index (ESI). In contrast, the HPHH treatment promoted the exchange of SH/SS bonds between protein molecules and facilitated the interaction of basic peptides and β-subunits, leading to larger particle sizes of the soluble aggregates compared to the HHPH-treated samples. However, excessive aggregation in HPHH-treated aggregates leads to decreased H0 and adsorbed protein content, and increased interfacial tension, negatively affecting the emulsification properties. Compared to the HPHH treatment, HHPH treatment at homogenization pressures of 20 to 100 MPa increases EAI and ESI by 5.81–29.6 % and 5.31–25.9 %, respectively. These findings provide a fundamental basis for soybean protein manufacturers to employ appropriate processing procedures aimed at improving emulsification properties.