Influence Of High-pressure Homogenization Research Articles

Application of High-Pressure Homogenization for Apple Juice: An Assessment of Quality Attributes and Polyphenol Bioaccessibility

In the current work, the influence of high-pressure homogenization (HPH) (200, 250, and 300 MPa) on pH, Brix, turbidity, viscosity, particle size distribution (PSD), zeta potential, color, polyphenol oxidase (PPO), peroxidase (POD), polyphenol profile and bioaccessibility of total phenolic compounds was studied. The results show no change in the apple juice's pH, TSS and density. In contrast, other physiochemical properties of apple juice treated with HPH were significantly changed. Besides total phenolic content (15% degradation) in the HPH-treated apple juice at 300 MPa, the PPO and POD activities were reduced by a maximum of 70 and 35%, respectively. Furthermore, among different digestion stages, various values corresponding to PSD and zeta potential were recorded; the total phenolic content was gradually reduced from the mouth to the intestine stage. The polyphenol bioaccessibility of HPH-treated apple juice was 17% higher compared to the untreated apple juice.

The influence of high pressure homogenization and high-intensity ultrasound on the functional properties of whey-protein/canola oil nanoemulsions during storage

The current work was conducted in order to explore the influence of two non-thermal technologies (high pressure processing (HPH) and high-intensity ultrasound (HIU) on the droplet size, turbidity and lipid oxidation of whey protein / canola oil nanoemulsions (WPN) during a week. The outcomes exhibited that the HIU process have a significant impact on both droplet size and lipid oxidation (p<0.05) of WPNs. A smaller droplet size was obtained for HPH treated WPNs compared to the control (untreated) WPNs. On the other hand, the smallest droplet sizes were obtained for the samples exposed to 10 min HIU at 100% amplitude (614.7 nm). The same sample also showed the least lipid oxidation during 7 days of storage (124 mmol/kg). There is a positive relationship between the variables of droplet sizes and turbidities. All HIU-treated WPN samples exhibited less turbidity and smaller droplet size where the control WPN samples demonstrated most turbid structure (5.97) with the biggest droplet sizes (985.4 nm). Similar positive relationship was also figured out between the variables of droplet size and lipid oxidation. All HIU-treated WPN samples exhibited less lipid oxidation and smaller droplet size where the control WPN samples demonstrated most lipid oxidation with the biggest droplet sizes.

High pressure homogenization with a cooling circulating system: The effect on physiochemical and rheological properties, enzymes, and carotenoid profile of carrot juice

The influence of high pressure homogenization (HPH) at 100–150 MPa performed by multiple passes below 35 °C on carrot juice quality and stability was studied. The highest reduction in microorganisms (by 2.47 log) was noted at 150 MPa with 5 passes of the juice through the homogenizer. The PPO and POD’s residual activity increased after HPH; PG was at the same level, while PME activity increased or decreased depending on the process parameters used. HPH treatment resulted in a decrease in the apparent dynamic viscosity, turbidity and colour parameters. Five passes at 150 MPa caused an increase in the carotenoid content, especially 9-Z-β-carotene (by 154%) while the TPC did not change significantly. Carrot juice treatment at 150 MPa with 5 passes may extend its shelf-life by 3 days when stored at 4 °C.

Production and Characterization of Sumac PlantCrystals: Influence of High-Pressure Homogenization on Antioxidant Activity of Sumac (Rhus coriaria L.).

Oxidative stress diseases are usually treated or prevented by using antioxidants from natural or artificial sources. However, as a sustainable source of phytochemicals, plants got a renewed interest in obtaining their active agents using green extraction technologies, i.e., sustainable extraction techniques that reduce energy consumption, use renewable sources and result in less post-extraction wastes. The high-pressure homogenization (HPH) technique was introduced into the food industry since it was invented in 1900 to homogenize milk and later to produce fruit juices with a longer shelf-life without preservatives. Recently, HPH was introduced as an eco-friendly method to nanomill plants for improved extraction efficacy without using organic solvents. In this study, sumac was used as an antioxidants-rich spice model to investigate the effects of HPH on its antioxidant capacity (AOC). Sumac was rendered into PlantCrystals by using HPH. Particle size characterization proved the presence of submicron-sized particles (about 750 nm). Thus, HPH was able to produce sumac PlantCrystals and increased the AOC of bulk sumac by more than 650% according to the ORAC (oxygen radical absorbance capacity) assay. The polyphenol and flavonoid contents showed higher values after HPH. Interestingly, the DPPH (1,1-diphenyl-2-picrylhydrazyl) assay also showed a well improved AOC (similar to ascorbic acid) after HPH. In fact, in this study, the PlantCrystal-technology was demonstrated to cause an efficient cell rupture of the sumac plant cells. This caused an efficient release of antioxidants and resulted in sumac PlantCrystals with a 6.5-fold higher antioxidant capacity when compared to non-processed sumac bulk material.

Influence of high pressure homogenization and pasteurization on the in vitro bioaccessibility of carotenoids and flavonoids in orange juice.

Production of high-quality healthy foods through sustainable methodologies is an urgent necessity. High pressure homogenization (HPH) is an interesting alternative to obtain premium citrus juices, but its effects on bioactive compounds are unclear. There was studied the influence of HPH (150MPa) and pasteurization (92°C for 30s and 85°C for 15s) processing on physicochemical properties and in vitro bioaccessibility of carotenoids and flavonoids in orange juices. Regarding fresh juice, physicochemical properties of samples remained unchanged although cloudiness was improved by homogenization. Pasteurization did not affect total carotenoids content and retinol activity equivalents (RAE) of juices whereas homogenization yielded a significant reduction (1.37 and 1.35-fold, respectively). Interestingly, particle size reduction from homogenization drastically enhanced (about 5-fold) bioaccessibility of carotenoids including hardly bioaccessible epoxycarotenoids, finding unaltered rates in pasteurized samples. Bioaccessibility of flavonoids was constant in all cases. Results can promote HPH as an efficient option to obtain health-enhanced foods.

Influence of high-pressure homogenization on structural properties and enzymatic hydrolysis of milk proteins

This study investigated the effects of HPH processing parameters on the conformational structure of bovine serum albumin (BSA) and whey protein isolate (WPI).BSA and WPI dispersions (1% w/v in phosphate buffer, pH = 7.5) were treated in a bench-scale HPH unit at different pressures (100, 150, 200 MPa) and number of passes (1, 2, 3, 5). The modifications of proteins' primary structure (carbonyl groups), secondary structure (α-helix, β-sheet, turn), tertiary and quaternary structure (free -SH groups) were analyzed together with their particle size distribution (PSD). HPH-assisted hydrolysis with trypsin and α-chymotrypsin was performed (200 MPa, 1 pass). Hydrolysis degree and molecular weight distribution of peptides were determined and compared with those of untreated protein dispersions.HPH treatments did not affect proteins' primary structure while slight modifications of secondary structure were detected. Interestingly, free - SH groups in BSA increased with increasing the pressure due to partial unfolding, while decreased in WPI, possibly due to disaggregation and compaction of native WPI aggregates. HPH pre-treatment allowed enhancing BSA hydrolysis reaction rate, while the compaction of WPI aggregates caused a reduced hydrolysis extent. In conclusion, HPH caused an appreciable modification of protein conformation and affected the degree of enzymatic hydrolysis.

Formulation and optimization of emulsions based on bitter fennel essential oil and EO/BO block copolymer surfactant

The influence of EO/BO block copolymer surfactant concentration in the range (1–5% (m/m)) and emulsification time on the emulsion stability and droplet size distribution of bitter fennel essential oil-in-water emulsions has been studied.Essential oils are promising material to be used for emulsion formulation with applications in cosmetics, food industry and agrochemicals. In the latter field these emulsions may be used as matrices for pesticides, where essential oils play the role of an eco-friendly solvent.A two-factor central composite design was conducted in order to optimize the emulsion formulation and processing. Emulsion stability has been studied as function of ageing time, by multiple light scattering (Turbiscan Lab-expert, Formulaction) and laser diffraction (Mastersizer X, Malvern). The surface response methodology allowed us to obtain a formulation comprising minimum droplet size and maximum stability by using a single step rotor/stator homogenization process.Creaming turned out to be the main destabilization mechanism. In order to improve emulsion stability the influence of high pressure homogenization (M110P, Microfluidics, MA, USA) and addition of a weighting agent (rosin gum) was studied. Although lower droplet sizes were obtained in both cases (D3,2 were in the range 0.30–0.35μm), emulsions were more unstable maybe due to Ostwald ripening phenomena.

Influence of high pressure homogenization with and without lecithin on particle size and physicochemical properties of whey protein‐based emulsions

AbstractThis study evaluated the quality attributes of high pressure homogenized whey protein emulsions with and without lecithin. Samples were prepared by mixing whey protein concentrate (10%), soybean oil (0 or 5%) and soy lecithin (0 or 5%). The premixtures were processed by a laboratory scale high pressure homogenizer at various pressures (25, 50, 75, and 100 MPa) at an initial temperature of 21 °C. The samples were evaluated for particle size, electrical conductivity, color, °Brix, and pH. Increasing homogenization pressures significantly decreased particle sizes of all samples. After 25 MPa treatment, emulsions with lecithin had smaller particle sizes than those made without lecithin. However, lecithin did not further reduce particle size for emulsion samples treated at ≥50 MPa. Electrical conductivity of samples increased with increasing homogenization pressures. Homogenization increased the lightness (L*) while reduced redness (a*) and yellowness (b*) of emulsions. The °Brix of emulsions increased after homogenization, but no change in pH was observed.Practical applicationsConsumer interest in clean label products prompted the food industry to investigate various processing methods such as high pressure homogenization to reduce additive use. The results of this study demonstrated the potential of applying high pressure homogenization in preparing whey protein‐based food products, with less use of lecithin.

Influence of high-pressure homogenization, ultrasonication, and supercritical fluid on free astaxanthin extraction from β-glucanase-treated Phaffia rhodozyma cells

ABSTRACTIn this study astaxanthin production by Phaffia rhodozyma was enhanced by chemical mutation using ethyl methane sulfonate. The mutant produces a higher amount of astaxanthin than the wild yeast strain. In comparison to supercritical fluid technique, high-pressure homogenization is better for extracting astaxanthin from yeast cells. Ultrasonication of dimethyl sulfoxide, hexane, and acetone-treated cells yielded less astaxanthin than β-glucanase enzyme-treated cells. The combination of ultrasonication with β-glucanase enzyme is found to be the most efficient method of extraction among all the tested physical and chemical extraction methods. It gives a maximum yield of 435.71 ± 6.55 µg free astaxanthin per gram of yeast cell mass.

Gelation of oil-in-water emulsions stabilized by whey protein

The effects of heat treatment and high-pressure homogenization on whey protein (WP) emulsion properties were evaluated. Only emulsion containing non-heated WP was stable, presenting low viscosity, small droplets and higher adsorbed protein content by increasing homogenization pressure. In addition, the influence of high-pressure homogenization and pH on cold-set gel formation by acidification of emulsion (emulsion gel) or emulsion dispersed in heat-treated WP solution (emulsion-filled gel) was studied. Only emulsion-filled gels were self-supported. Stronger gels were observed at pH near WP isoelectric point due to lower acidification rate and electrostatic repulsion that promoted more intense protein aggregation. Varying emulsion homogenization pressure resulted in different gel network strength caused by changing dispersed phase volume fraction and adsorbed protein content. Therefore, depending on process conditions cold-set gel of emulsion can be produced and it shows a great potential to be used in food formulations as texturizing agent and/or as a carrier for heat-labile ingredients.

Influence of high-pressure homogenization on functional properties of orange pulp

Abstract The current work evaluated whether high-pressure homogenization (HPH) could functionalize orange pulp in terms of water holding and swelling capacity and rheological properties. The orange pulp particle size was gradually decreased by applying HPH at increasing pressure (200 and 800 bar) whereby the mechanical impact at 800 bar resulted in the appearance of a more homogeneous, smoother suspension with a twofold increase in yield stress. HPH also affected the pectin properties within the orange pulp cell walls. More specifically, HPH at 800 bar increased the relative presence of water-extractable pectin. By investigating subsamples containing particles with different sizes isolated from orange pulp before and after HPH, it became clear that particle size is inversely related to water holding capacity and the ability of the particle network to deform prior to flow. Especially highly disintegrated orange pulp material ( Industrial relevance Orange pulp is of particular interest in the context of producing fiber-rich functional ingredients because of its large quantity available within the juice industry. High-pressure homogenization (HPH) at pressures higher than the ones usually applied in food industry seems required to functionalize orange pulp as HPH at 200 bar (a common pressure applied in the food industry) could not increase the relative presence of small particles, contributing to water holding capacity and soft particle network behavior, as substantially compared to HPH at 800 bar.

Influence of high pressure homogenization on commercial protease from Rhizomucor miehei: Effects on proteolytic and milk-clotting activities

This work studied the influence of high pressure homogenization (HPH) on a commercial fungal protease. The enzyme solutions (2 and 20 g/100 mL) were processed up to 190 MPa and the proteolytic activity (PA), milk-clotting activity (MCA) and the rheological behavior of the milk coagulation phase were evaluated. The effects of multi-pass (three cycles) HPH at 25 and 190 MPa was evaluated for enzyme processed at concentration of 2 g/100 mL. No differences in PA and MCA were observed for the samples of 2 g/100 mL of enzyme concentration processed by HPH. On the other hand, increase in PA (∼3%) and MCA (∼10%) were observed for the enzymes processed at 190 MPa at high concentration, which consequent faster clotting and higher consistency of the milk gel. The multi-pass increased PA (≤6%) but did not alter MCA nor improved the milk coagulation phase. The results highlight that the energy supplied from HPH to enzyme at low concentration is not enough to promote positive changes in the enzyme coagulant profile; however, the HPH of solution with high enzyme concentration showed a positive effect, indicating that the collisions between enzymes during the process was important to reach the observed changes.

Influence of high pressure homogenization and pulp reduction on residual pectinmethylesterase activity, cloud stability and acceptability of Lane Late orange juice: A study to obtain high quality orange juice with extended shelf life

Lane Late orange juice with extended shelf life (3months at 3°C) was obtained by high pressure homogenization (HPH) at 150MPa at 68°C for 15s. Residual pectinmethylesterase (PME) inactivation level achieved was 75% but its cloudiness was maintained during storage and its acceptability undistinguishable from that of fresh juice during the assayed period. Juices with entire and reduced (50% and 25%) pulp contents were also homogenized at 150MPa at different temperatures (63°C and 58°C for 15s) to establish an appropriate shelf life of orange juices according to a desired level of cloudiness. Results showed how cloud stability of pulp reduced samples, even with a residual PME inactivation level above 90%, was not satisfactory (as in the case of entire juices homogenized out of 68°C). The proposed methodology can easily be implanted by citrus industry to obtain high quality chilled orange juices with prolonged shelf life.

Influence of high pressure homogenization (HPH) on the structural stability of an egg/dairy emulsion

Abstract High pressure homogenization (HPH) is a novel non-thermal preservation technology, which can improve the microbiological quality of products without affecting their stability. The main objective of this paper is to study the influence of different HPH treatments on the structure of a sauce (an egg/dairy emulsion), in order to obtain the higher physicochemical stability. The oil-in-water emulsion was stable up to 100 MPa with the oil droplets surrounded by several layers of natural emulsifiers. Critical pressures, between 150 and 250 MPa, produced a destabilization of the emulsion thus causing a separation of phases. A coalescence phenomenon progressively occurred when pressure increased. This phenomenon was due to the loss of the natural emulsifier barrier. Changes on the electrophoretic pattern were also observed at high pressure levels, showing an insolubilization of proteins. Lipid fraction was observed to be chemically stable after the HPH treatment.