Sugar Beet Pectin Research Articles

Visible light photocrosslinking of sugar beet pectin for 3D bioprinting applications

Herein, we report the hydrogelation of sugar beet pectin (SBP) via visible light-mediated photocrosslinking and its applications in extrusion-based 3D bioprinting. Rapid hydrogelation (<15 s) was achieved by applying 405 nm visible light to an SBP solution in the presence of tris(bipyridine)ruthenium(II) chloride hexahydrate ([Ru(bpy)3]2+) and sodium persulfate (SPS). The mechanical properties of the hydrogel could be tuned by controlling the visible light irradiation time and concentrations of SBP, [Ru(bpy)3]2+, and SPS. High-fidelity 3D hydrogel constructs were fabricated by extruding inks containing 3.0 wt% SBP, 1.0 mM [Ru(bpy)3]2+, and 1.0 mM SPS. Human hepatoblastoma (HepG2) cells encapsulated in SBP hydrogels remained viable and metabolically active after 14 d of culture. Overall, this study demonstrates the feasibility of applying SBP and a visible light-mediated photocrosslinking system to the 3D bioprinting of cell-laden constructs for tissue engineering applications.

Pickering emulsions synergistically stabilized by sugar beet pectin and montmorillonite exhibit enhanced storage stability and viscoelasticity

Sugar beet pectin (SBP) is a naturally occurring emulsifying type of pectin fabricated into nanocomposites with montmorillonite (MMT) and then introduced as a stabilizer for high internal phase emulsions (HIPEs). SBP-MMT composites performed well in emulsifying medium-chain triglyceride with an oil volume fraction (φ) of 0.1–0.85 and SBP/MMT mass ratios of 1:0.1–1:0.75. The two representative high internal phase emulsions stabilized by SBP-MMT composites at different SBP/MMT mass ratios exhibited good stability against creaming and coalescence. In these emulsion systems, SBP and MMT formed a network in the continuous phase that markedly improved the rheological properties, including the storage modulus (by 3 orders of magnitude). Confocal light scattering microscopy analysis indicated that a fraction of MMT could work synergistically with SBP in adsorbing on oil droplet surfaces, enhancing stability. SBP-MMT composites stabilized high internal phase emulsions destabilized after the freeze-thaw treatment (−40 °C for 20 h and 25 °C for 4 h) but could be facilely re-emulsified via high-speed shearing. The gastrointestinal digestion behaviors were also modified by stabilizing SBP and MMT. Overall, this work reveals a hitherto undocumented strategy for fabricating highly stable emulsions based on SBP-MMT composites which have huge prospects for application in the food and related industries.

Understanding the impact of pectin physicochemical variation on browning of simulated Maillard reaction system in thermal and storage processing

Maillard reaction browning is one of the quality deterioration in dried fruit products, but how pectin affects Maillard reaction in the fruit drying and storage process is not clear. This study aimed at investigating the mechanism of pectin variation impact on the browning of Maillard reaction by using simulated system (l-lysine, d-fructose and pectin) in thermal (60 °C and 90 °C for 8 h) and storage (37 °C for 14 days) process. Results showed that apple pectin (AP) and sugar beet pectin (SP) significantly enhanced the browning index (BI) of the Maillard reaction system by 0.01 to 134.51 in the thermal and storage processes, respectively, which were methylation degree of pectin-dependent. The pectin depolymerization product participated Maillard reaction by reacting with l-lysine, and increasing the 5-hydroxymethyl furfural (5-HMF) content (1.25–11.41-fold) and Abs420nm (0.01–0.09). It also produced a new product (m/z 225.1245), which finally increased browning level of the system.

Design and characterization of low salt myofibrillar protein-sugar beet pectin double-crosslinked gels pretreated by ultrasound and konjac glucomannan: Conformational and gelling properties

The purpose of this study was to investigate the influence of two-step sequential cross-linking induced by laccase and heat treatment on the conformation and gelling properties of low-salt myofibrillar proteins (MP) modified by konjac glucomannan (KGM) and ultrasound treatments. Adding sugar beet pectin (SBP), irrespective of laccase crosslinking, significantly decreased the fluorescence intensity of low-salt MPs (MP, UMP, UMP-KGM). Laccase crosslinking caused the exposure of hydrophobic and Tyr residues, induced moderate aggregation of MPs, and enhanced rheological properties and gel strength of composite MP gels, especially in the UMP-KGM sample. This result could also be corroborated by the highest WHC, improved textural characteristics, enhanced intermolecular interactions, and increased percentage in t-g-g conformation of S–S bridges in the SBP modified UMP-KGM gel after laccase crosslinking. Therefore, the dual crosslinking could be used to regulate the protein-protein and protein-polysaccharide interactions and improve the gel properties of low-salt meat products.

Synergistic effects of sugar beet pectin and laccase on gel properties of egg white

It is of great significance to improve the gel properties of egg white for their related products. This goal was accomplished by investigating the gel properties of egg white via interacting with pectin and laccase, and revealing their mechanisms. Results showed that 0.06% sugar beet pectin (SBP) and 0.5 U/g laccase could endow egg white gels with better texture properties (with the highest hardness of 1 508.00 g, chewiness of 1 144.83, and gumminess of 1 210.57), and superior water holding capacity (WHC) (the highest WHC value of 72.08%). This was attributed to the fact that 0.06% of SBP filled the pores of egg white gel, and enhanced affinity and binding of the gels to water by the good hydrophilicity of SBP, and the decrease in egg white gel pore size. Laccase (0.5 U/g) could promote the cross-linking between the egg white gel and SBP to form a more complex gel network structure through the interactions between the tyrosine residues and ferulic acid in SBP, which brought more ionic bonds (22.47%), hydrogen bonds (12.4%), disulfide bonds (16.97%) and more compact structure to egg white gels. This work can provide an effective method to improve the quality of egg white gel and related products.

Influences of Ultrasonic Treatments on the Structure and Antioxidant Properties of Sugar Beet Pectin

The objective of this study was to explore the structural changes and oxidation resistance of ultrasonic degradation products of sugar beet pectin (SBP). The changes in the structures and antioxidant activity between SBP and its degradation products were compared. As the ultrasonic treatment time increased, the content of α-D-1,4-galacturonic acid (GalA) also increased, to 68.28%. In addition, the neutral sugar (NS) content, esterification degree (DE), particle size, intrinsic viscosity and viscosity-average molecular weight (MV) of the modified SBP decreased. Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM) were used to study the degradation of the SBP structure after ultrasonication. After ultrasonic treatment, the DPPH and ABTS free radical scavenging activities of the modified SBP reached 67.84% and 54.67% at the concentration of 4 mg/mL, respectively, and the thermal stability of modified SBP was also improved. All of the results indicate that the ultrasonic technology is an environmentally friendly, simple, and effective strategy to improve the antioxidant capacity of SBP.

Co-expression of thermophilic pectinases in a single host for cost-effective pectin bioconversion into D-galacturonic acid

Co-expression of enzymes allow to produce multiple enzymes in a single host, representing a cost-effective alternative in biocatalytic processes which can be used for pectin bioconversion. Pectin-rich biomass is an abundant by-product from the fruit and sugar industries that is usually disposed in landfill or sold as a low value feedstock. The aim of this work was to co-express a thermophilic pectin methyl esterase (PME) and exo-polygalacturonases (exo-PGs) in a single host for pectin bioconversion into D-galacturonic acid (GalA) using different pectic substrates such as apple, citrus and sugar beet pectin. To achieve this, a PME from Bacillus licheniformis (BLI09) with either an exo-PG from Thermotoga maritima (TMA01) or from Bacillus licheniformis (BLI04) were cloned in pETDuet-1 and co-expressed in E. coli BL21 (DE3). Four co-expression plasmids containing both pectinases were constructed and factors such as the effect of the genes’ cloning order and their expression were evaluated. Co-expression constructs 3 and 4 (pETDuet-TMA01-BLI09 and pETDuet-BLI04-BLI09, respectively) showed better expression of both pectinases compared to co-expression constructs 1 and 2 (pETDuet-BLI09-TMA01 and pETDuet-BLI09-BLI04, respectively). Co-expression constructs 3 and 4 were the most efficient for pectin bioconversion into GalA reaching 3 and 2.5 mM GalA, respectively from apple and citrus pectin after 4 h reaction. In conclusion, this work demonstrates that the co-expression of pectinases can potentially contribute to reduce the cost associated to their production and purification as well as to increase their applicability for exploiting pectin-rich biomass to obtain bio-based chemicals.

Sugar beet pectins for the formulation of dressings and soft drinks: Understanding the complexity of charged hydrocolloids in industrial food emulsions

The aim of this study was to set up formulation-process-property functions for sugar beet pectin stabilized emulsions under industrially relevant processing conditions to allow for a reformulation of foods and beverages using sugar beet pectins (SBP) as emulsifiers. Therefore, model food emulsions, soft drinks, and salad dressings were produced. Model emulsions were prepared at different pH values (3, 4, and 5) and varying SBP concentrations (0.25 wt% – 2 wt%). Subsequently, the emulsions were subjected to pasteurization or salt addition and their short- and long-term stability was assessed. It could be shown that the pectin-stabilized emulsions were more sensitive to salt addition than to heat treatment. However, any physical instabilities could be avoided by using higher amounts of SBP. Furthermore, it could be shown, that SBP are able to stabilize soft drinks (0.05 wt% orange oil) as well as low-fat salad dressings (10 wt% rapeseed oil) over the typically required storage time. SBP-stabilized soft drinks showed no significant changes in droplet size distributions, cloudiness, or color, even after pasteurization and 6 months of storage. In order to stabilize the salad dressings with a rather low SBP concentration (0.25 wt%), the viscosity of the samples had to be adjusted appropriately. Overall, SBP were shown to be highly suitable for use as emulsifiers in the food and beverage industry. • Emulsions with SBP were more sensitive to higher ionic strengths at pH 3 than pH 5. • Pasteurization had no significant effect on droplet size distribution. • SBP concentration was the most important formulation parameter for stability. • An unfavorable pH and ionic strength could be compensated by higher amounts of SBP. • SBP-stabilized salad dressings were stable over 4 weeks, soft drinks over 6 months.

Elucidation of the cellulose nanocrystal-sugar beet pectin interactions for emulsification enhancement

Commercial emulsions are usually stabilized by multi-component formulations, such as particle and biopolymer, rather than single emulsifiers. However, their interactions and contributions to emulsification are complicated and lack elucidations. This work investigates the interaction between cellulose nanocrystal (CNC) and sugar beet pectin (SBP) and their performance in emulsion stabilization. The irreversible adsorption of SBP onto the CNC surface was verified by Quartz Crystal Microbalance with Dissipation (QCM-D) and atomic force microscopy. The molecular structure-based adsorption mechanism was elucidated by the enzymatic hydrolysis technique, revealing that the neutral sugar side chains (rich in protein and ferulic acid) were the main adsorbable components of SBP, which was predominately driven by hydrophobic interactions. At the CNC: SBP ratio of 3:1, the mixture of SBP-coated CNC and free SBP showed synergistic emulsification performance. The incorporation of CNC significantly improved the anchoring rate of SBP at the oil-water interface during emulsification to produce smaller emulsion droplets. The hybrid coverage of SBP-coated CNC and free SBP endowed the droplets with more robust repulsion to maintain long-term stability. These findings provide a feasible and convenient way for modulating the emulsifying properties of CNC by changing the compositional formulation. • Cellulose nanocrystal (CNC) adsorbed with sugar beet pectin (SBP) in solution. • The adsorbable fractions of SBP were neutral sugar, protein, and ferulic acid. • The interaction was predominated by hydrophobic interaction. • CNC and SBP showed a synergistic stabilization effect to stabilized emulsions.

Solidification of concentrated pea protein-pectin mixtures as potential binder.

Binders in plant-based meat analogues allow different components, such as extrudate and fat particles, to stick together. Typically, binders then are solidified to transform the mass into a non-sticky, solid product. As an option for a clean-label binder possessing such properties, the solidification behavior of pea protein-pectin mixtures (250 g kg-1 , r=2:1, pH6) was investigated upon heating, and upon addition of calcium, transglutaminase, and laccase, or by combinations thereof. Mixtures of (homogenized) pea protein and apple pectin had higher elastic moduli and consistency coefficients and lower frequency dependencies upon calcium addition. This indicated that calcium physically cross-linked pectin chains that formed the continuous phase in the biopolymer matrix. The highest degree of solidification was obtained with a mixture of pea protein and sugar beet pectin upon addition of laccase that covalently cross-linked both biopolymers involved. All solidified mixtures lost their stickiness. A mixture of soluble pea protein and apple pectin solidified only slightly through calcium and transglutaminase, probably due to differences in the microstructural arrangement of the biopolymers. The chemical makeup of the biopolymers and their spatial distribution determines solidification behavior in concentrated biopolymer mixtures. In general, pea protein-pectin mixtures can solidify and therefore have the potential to act as binders in meat analogues. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Evaluation of sugar beet pectin viscosity, surface activity, conductivity and zeta potential in sodium chloride aqueous solutions

Application of hydrocolloids is highly dependent on their structural and conformational properties. Molecular weight, macromolecular geometry, hydrophobicity and electric charge are, therefore, often researched. In the presented study, influence of sodium chloride on conformation and structure of sugar beet pectin in aqueous solutions was first time thoroughly characterized. Viscosity, surface tension, specific conductivity, zeta potential and pH of sugar beet pectin aqueous solutions were monitored and measured following the addition of sodium chloride. Relative viscosity of sugar beet pectin aqueous solutions decreased by up to 29.19% following the addition of sodium chloride. The highest decrease in relative viscosity values was noticed at the lowest sodium chloride concentrations used (0.2 g L−1 to 2 g L−1). The corresponding changes at the lowest sodium chloride concentrations used were also noticed in the obtained specific conductivity curves. Calculated diameter of sugar beet pectin macromolecule decreased by 19.98% following the addition of 10 g L−1 sodium chloride. Surface tension values of sugar beet pectin aqueous solutions were strongly influenced by the addition of sodium chloride. Decrease in zeta potential of sugar beet pectin aqueous solutions with addition of sodium chloride was observed. Presented results suggested that the addition of sodium chloride to sugar beet pectin aqueous solution could cause conformational changes of macromolecular chain suggesting possible transition from linear to globular conformation.

Influence of Arabinan Fine Structure, Galacturonan Backbone Length, and Degree of Esterification on the Emulsifying Properties of Acid-Extracted Sugar Beet Pectins

Sugar beet pectins (SBPs) are known for their emulsifying properties, but it is yet unknown which structural elements are most important for functionality. Recent results indicated that the arabinose content has a decisive influence, but the approach applied did not allow causality to be established. In this study, a mostly intact SBP was selectively modified and the obtained pectins were analyzed for their molecular structure and their emulsifying properties. De-esterification only resulted in a moderate increase in droplet size. The length of the pectin backbone only influenced the emulsifying properties when the homogalacturonan backbone was cleaved to a higher extent. By using different arabinan-modifying enzymes, it was demonstrated that both higher portions and chain lengths of arabinans positively influence the emulsifying properties of SBPs. Therefore, we were able to refine the structure-function relationships for acid-extracted SBPs, which can be used to optimize extraction conditions.

The preparation of soy glycinin/sugar beet pectin complex network gels catalyzed by laccase under weakly acidic conditions.

Traditional soy protein gel products such as tofu, formed from calcium sulfate or magnesium chloride, have poor textural properties and water retention capacity. Soy glycinin (SG) is the main component affecting the gelation of soy protein and can be cross-linked with polysaccharides, such as sugar beet pectin (SBP), and can be modified by changing system factors (e.g., pH) to improve the gel's properties. Soy glycinin/sugar beet pectin (SG/SBP) complex double network gels were prepared under weakly acidic conditions using laccase cross-linking and heat treatment. The structural changes in SG and the properties of complex gels were investigated. Soy glycinin exposed more hydrophobic groups and free sulfhydryl groups at pH5.0. Under the action of laccase cross-linking, SBP could promote the unfolding of SG tertiary structures. The SG/SBP complex gels contained 46.77% β-fold content and had good gelling properties in terms of hardness 290.86 g, adhesiveness 26.87, and springiness 96.70 mm at pH5.0. The T22 relaxation time had the highest peak, and magnetic resonance imaging (MRI) showed that the gel had even water distribution. Scanning electron microscopy (SEM) and confocal scanning laser microscopy (CLSM) indicated that the SG/SBP complex network structure was uniform, and the pore walls were thicker and contained filamentous structures. Soy glycinin/ sugar beet pectin complex network gels have good water-holding, rheological, and textural properties at pH5.0. The properties of soy protein gels can be improved by binding to polysaccharides, with laccase cross-linked, and adjusting the pH of the solution. © 2022 Society of Chemical Industry.

Pea protein–sugar beet pectin binders can provide cohesiveness in burger type meat analogues

Methylcellulose is commonly used in meat analogues for binding ingredients. In this study, we compared the binding properties of a methylcellulose hydrogel (5% w/w) to a novel, clean-label binder based on a mixture of pea protein and sugar beet pectin (r = 2:1, 22.5% w/w, pH 6.0) with and without laccase addition in a burger type meat analogue. It was shown that the pea protein–pectin binder glued vegetable protein particles and fat mimic particles together prior to cooking and frying, thereby improving forming of the mass into burger patties. Furthermore, sensory analysis revealed that the cohesiveness of the fried burger patties was better when the protein–pectin binder was used. However, the used binder system did not affect the hardness of the burger patties indicating that the binders rather affected the coherence of the structural elements. Burgers with solid fat particles were rated better in terms of appearance as compared to emulsified fat particles, since the former were not visible. This study is useful to better understand meat analogue product design for a higher acceptance among consumers.

Interaction of sugar beet pectin and pea protein: Impact of neutral sugar side chains and acetyl groups

Sugar beet pectin (SBP) is becoming increasingly interesting due to its complex molecular structure and emulsifying properties. Compared to citrus pectin, SBP differs, for example, in the content of neutral sugar side chains and acetyl groups. In this study it was assumed that side chains lead to steric hindrance between SBP and pea protein and the electrostatic interactions are reduced. Therefore, the aim of the present study was to investigate the impact of the neutral sugar side chains of SBP on steric hindrances and the impact of the acetyl groups on the interaction with pea protein.The interaction of four SBP samples varying in the content of neutral sugar side chains and three SBP samples differing in degree of acetylation with soluble pea protein fractions were investigated. Electrostatic interaction between SBP and protein was qualitatively tested via turbidity measurements and the results were presented in state diagrams. Quantitative evaluation of the interactions was obtained by isothermal titration calorimetry (ITC).The highest interaction was obtained for both SBP sample sets by a protein-to-pectin ratio of 4:1. Less content of neutral sugars resulted in enhanced maximum turbidity. This was confirmed by the ITC measurement, where more possible binding sites and a higher binding affinity was observed. A higher content of acetyl groups increased the interaction with the pea protein, which was supported by the turbidity and ITC measurement. These effects need to be considered when using SBP for designing new systems with plant-based proteins in the food and pharmaceutical industry.

Physicochemical and functional properties of cross linked and high pressure homogenized sugar beet pectin: A comparative study

Chemical cross-linking and high pressure homogenization are two methods to improve techno-functional properties of pectin. In this study, the effect of high pressure homogenization (HPH) variables including pressure (200, 600 and 1000 bar), numbers of passes through homogenization valve (1, 3 and 5 times) and pH (3.1, 3.6 and 4.1) on viscosity, water holding capacity (WHC), oil holding capacity (OHC) and emulsion properties of sugar beet pectin were studied. The functional properties of pectin improved at higher homogenization pressure, more numbers of passes and lower pHs. Cross-linking, as a traditional chemical modification was also performed with the presence of 1, 2, 3, 5% pectin reacting with ammonium persulfate. The degree of esterification (DE) and Mw of pectin increased for 1–3% reactant pectin followed by a decrease for 5% of pectin due to steric hindrance. The Fourier Transform Infrared (FTIR) and ferulic acid content confirmed the changes in cross-linking efficiency. It was also revealed that HPH could break the cross-bonds between ferulic acids and reduce the ferulic acid dehydrodimer. The maximum emulsion stability of cross-linked pectins was obtained for 3% reactant pectin while it was still lower than that of optimized HPH treated pectin. X-ray diffraction showed amorphous structure of pectin with no considerable change after chemical or mechanical modification. Scanning electron micrographs indicated more profound impact of HPH treatment on surface properties of pectin rather than cross-linkage. However, HPH treatment reduced the thermal stability of pectin in contrast to cross-linking modification. • High homogenization pressure and cycles and low pH enhanced pectin functionality. • HPH treatment broke crystalline structure and ferulic acid cross-links. • HPH treated pectin showed better functional properties than cross-linking ones.

Preparation of SP/Lysozyme Composite Gel and the Inhibition of Staphylococcus aureus

Soy glycinin (SG) and sugar beet pectin (SBP) were cross-linked using laccase to form a complex SG/SBP (SP) and then combined with lysozyme under the heating condition to form SP/lysozyme composite gels. The properties of SP/lysozyme composite gel and its inhibition on Staphylococcus aureus were investigated. Results revealed that the zeta potential changed from −32 to 8.2 mV upon adding lysozyme, its morphology was larger, and the particle size and turbidity increased. The Fourier transform infrared spectroscopy and X-ray diffraction results indicated that the interactions between SP and lysozyme were electrostatic interaction and hydrogen bonding. The mechanical properties showed that the SP/lysozyme composite gel could recover its original shape after 90% strain compression when SP/lysozyme was 10:4 and 10:5, and the storage modulus (G′) was higher at 10:5 about 105 Pa. Scanning electron microscopy results showed that the granular size increased, and the antibacterial property on S. aureus was enhanced.

Comparison of Binding Properties of a Laccase-Treated Pea Protein–Sugar Beet Pectin Mixture with Methylcellulose in a Bacon-Type Meat Analogue

A bacon-type meat analogue consists of different structural layers, such as textured protein and a fat mimetic. To obtain a coherent and appealing product, a suitable binder must glue those elements together. A mixture based on pea protein and sugar beet pectin (r = 2:1, 25% w/w solids, pH 6) with and without laccase addition and a methylcellulose hydrogel (6% w/w) serving as benchmark were applied as binder between textured protein and a fat mimetic. A tensile strength test, during which the layers were torn apart, was performed to measure the binding ability. The pea protein-sugar beet pectin mixture without laccase was viscoelastic and had medium and low binding strength at 25 °C (F ≤ 3.5 N) and 70 °C (F ≈ 1.0 N), respectively. The addition of laccase solidified the mixture and increased binding strength at 25 °C (F ≥ 4.0 N) and 70 °C (F ≈ 2.0 N), due to covalent bonds within the binder and between the binder and the textured protein or the fat mimetic layers. Generally, the binding strength was higher when two textured protein layers were glued together. The binding properties of methylcellulose hydrogel was low (F ≤ 2.0 N), except when two fat mimetic layers were bound due to hydrophobic interactions becoming dominant. The investigated mixed pectin-pea protein system is able serve as a clean-label binder in bacon-type meat analogues, and the application in other products seems promising.

Structural and physical properties of spray-dried fish oil microcapsules via pea protein isolate based emulsification or complex coacervation with sugar beet pectin

The aim of this study is to compare the type of infeed dispersions, i.e., fish oil (FO) emulsions stabilized by single-shelled pea protein isolate (PPI) and FO–PPI–sugar beet pectin (SBP) double-shelled complex coacervates on structural and physical properties of spray-dried FO microcapsules. The results show that FO–PPI–SBP complex coacervates formed at pH 3.5 possess bigger particle size and denser network structures rather than those produced at higher pHs (4.5 and 4.0). Nevertheless, the encapsulation performance of both types of infeed dispersions is quiet similar, and they afford a relative low encapsulation efficiency (22.80%–27.78%). FTIR confirms that electrostatic interaction dominates the formation of complex coacervates based microcapsules. SEM shows the spherical shape of all microparticles without cracking or fissures; while oil spot is visualized in emulsification based microcapsules. Unlike emulsification, DSC indicates the raised denaturation temperature of PPI in the FO microcapsules due to PPI–SBP interactions. This study suggests that PPI alone with a lower concentration is insufficient to microencapsulate fish oil; while the addition of SBP for the formation of double-shelled PPI–SBP complex coacervates particularly at pH 3.5 could be a practical and economic solution for fish oil microencapsulation. • Plant protein (PPI) and pectin (SBP) are used to produce fish oil (FO) powders. • FO infeed dispersions are prepared via PPI emulsions or PPI-SBP complex coacervates. • pH is critical to determine physical properties of dispersions and microcapsules. • Encapsulation performance is independent of the type of infeed dispersions. • Smooth surface without cracks or holes are revealed for microcapsules with PPI-SBP

Can Enzymatic Treatment of Sugar Beet Pectins Reduce Coalescence Effects in High-Pressure Processes?

While sugar beet pectins (SBPs) are well known for effectively stabilizing fine oil droplets in low-fat food and beverages, e.g., low-fat dressings and soft drinks, it often fails in products of higher oil contents. The aim of this study was to improve the emulsifying properties of SBPs and, consequently, their ability to reduce coalescence during high pressure homogenization of products with increased oil content. Therefore, the molecular size of SBPs was reduced by partial cleavage of the homogalacturonan backbone using the enzymes exo- and endo-polygalacturonanase and varying incubation times. The sizes of SBPs were compared based on the molecular size distribution and hydrodynamic diameter. In addition, to obtain information on the interfacial activity and adsorption rate of SBPs, the dynamic interfacial tension was measured by drop profile analysis tensiometry. The (non)modified SBPs were used as emulsifying agents in 30 wt% mct oil–water emulsions stabilized with 0.5 wt% SBP at pH 3, prepared by high-pressure homogenization (400–1000 bar). By analyzing the droplet size distributions, conclusions could be drawn about the coalescence that occurred after droplet breakup. It could be shown that SBPs modified by exo-polygalacturonanase stabilized the oil–water interface more rapidly, resulting in less coalescence and the smallest oil droplets. In contrast, SBPs modified with endo-polygalacturonanase resulted in poorer emulsification properties, and thus larger oil droplets with increasing incubation time. The differences could be attributed to the different cleavage pattern of the enzymes used. The results suggest that a minimum molecular size is required for the stabilization of fine oil droplets with SBPs as emulsifiers.