The Effects of Pectin Structure on Emulsifying, Rheological, and In Vitro Digestion Properties of Emulsion

Long-term storage of pink pepper essential oil microencapsulated by chickpea protein/pectin complexes: volatile release, antioxidant and antimicrobial activities

Pink pepper essential oil was microencapsulated with chickpea protein (CP) and chickpea protein/pectin (CP-HMP) by spray drying. The reconstitution and storage properties of the powders were evaluated after drying. The impact of microencapsulation in the volatiles release, antioxidant and antimicrobial activity of oil was evaluated during 135 days of storage. CP resulted in more soluble powders (93.52%), CP/HMP resulted in denser powders (0.39 g/mL) while wall material did not influence the wettability. Free pink pepper essential oil (FEO) showed a slight loss of the predominant terpenes (α-pinene, β-pinene, β-mircene, δ-3-carene and D-limonene) after encapsulation. In general, all samples showed an increase in the volatiles release during storage. The evaluation of mass loss showed that FEO had a high release of volatiles, followed by CP and CP-HMP. The antioxidant activity of the FEO decreased (10.8 μg Trolox/mg of oil) after 135 days of storage, whereas the antioxidant activity of CP (14.9) and CP-HMP (14) increased. Both microcapsules presented antimicrobial activity against Bacillus subtilis and Staphylococcus aureus during storage. CP microcapsules had a strong inhibitory effect against the strains tested, and this advantage was even more evident in long-term storage.

Sequential extraction of hawthorn pectin: An attempt to reveal their original mode of being in plants and functional properties

Hawthorn is rich in pectin, which is much higher than most cultivated fruits, but conventional extraction methods do not meet the requirements of low energy consumption and green production. Pectin in hawthorn is divided into soluble and insoluble parts, and with the ripening of hawthorn, the original pectin is converted into soluble pectin and pectic acid under the action of enzymes. Therefore, based on the characteristics of hawthorn pectin, this study sequentially extracted hawthorn pectin using water-soluble pectin (WSP) and hot acid-soluble pectin (HAP) method, verifying the feasibility of extracting hawthorn pectin with pure water at room temperature, and systematically analyzing and comparing the physicochemical properties and functional characteristics of the two methods. The combination of texture analysis and gel rheology revealed that WSP formed a more uniform and dense network structure during the gelation process. Additionally, microscopic observations and emulsification index results indicated that the emulsion prepared with WSP (WSE) had a smaller particle size and better stability. This indicates that hawthorn pectin is suitable for extraction with pure water at room temperature, which can maintain its good physical properties while reducing energy consumption, providing a new approach for the large-scale extraction of pectin in the food industry.

Innovative biopolyelectrolytes-based technologies for wastewater treatment

Developing eco-friendly, cost-effective, and efficient methods for treating water pollutants has become paramount in recent years. Biopolyelectrolytes (BPEs), comprising natural polymers like chitosan, alginate, and cellulose, have emerged as versatile tools in this pursuit. This review offers a comprehensive exploration of the diverse roles of BPEs in combating water contamination, spanning coagulation-flocculation, adsorption, and filtration membrane techniques. With ionizable functional groups, BPEs exhibit promise in removing heavy metals, dyes, and various pollutants. Studies showcase the efficacy of chitosan, alginate, and pectin in achieving notable removal rates. BPEs efficiently adsorb heavy metal ions, dyes, and pesticides, leveraging robust adsorption capacity and exceptional mechanical properties. Furthermore, BPEs play a pivotal role in filtration membrane techniques, offering efficient separation systems with high removal rates and low energy consumption. Despite challenges related to production costs and property variability, their environmentally friendly, biodegradable, renewable, and recyclable nature positions BPEs as compelling candidates for sustainable water treatment technologies. This review delves deeper into BPEs' modification and integration with other materials; these natural polymers hold substantial promise in revolutionizing the landscape of water treatment technologies, offering eco-conscious solutions to address the pressing global issue of water pollution.

Mixed κ/ι-carrageenan - LM pectin gels: Relating the rheological and mechanical properties with the capacity for probiotic encapsulation

The rheological and mechanical properties of mixed κ/ι-carrageenan - LM pectin gels were determined, and the potential of these gels for the formation of beads using the extrusion method and for the encapsulation of Lacticaseibacillus rhamnosus ATCC 53103 (LGG) was evaluated. Self-standing gels were obtained with all formulations evaluated. Carrageenan-rich gels, with carrageenan fraction (XC) ≥ 0.75, exhibited the highest storage modulus, but they were also brittle, while pectin-rich gels (XC ≤ 0.25) presented the highest hardness and cohesiveness. Pectin-rich formulations formed beads with the smallest initial diameter (2.40-2.45 mm), and the addition of carrageenan produced significantly more spherical beads compared to pure-pectin ones. As pectin-rich beads were the formulations that resisted simulated gastrointestinal conditions, these were selected for the encapsulation of LGG. These beads showed high encapsulation yields (87-96 %), and the percentage reduction of CFU/g during storage and simulated gastrointestinal conditions was not significantly different among formulations, the latter being significantly lower for encapsulated cells (8.64-15.03 %) compared to free cells (71.20 %). These results indicate that carrageenan-pectin gel beads with XC ≤ 0.25 were successful in encapsulating probiotic bacteria, and this capacity was related to the rheological and mechanical properties of the gels.

Physicochemical and antioxidant properties of pectin from Actinidia arguta Sieb.et Zucc (A. arguta) extracted by ultrasonic

Pectin was extracted from Actinidia arguta Sieb. et Zucc (A.arguta) using the ultrasound-assisted acid method and the single acid method. The physicochemical properties, structure, and antioxidant properties of two different pectins were investigated. The results showed that the extraction yield of the ultrasound-assisted acid method is higher than that of the single acid method. The molecular structure of A. arguta pectin extracted by the ultrasound-assisted acid method belongs to a mixed structure of RG-I and HG-type domains. Through structural feature analysis, the ultrasound-assisted extraction pectin (UAP) has a more branched structure than the single acid-extracted pectin (SAP). The SAP has a higher degree of esterification than the UAP. The physical property results show that the viscosity, solubility, and water-holding capacity of the UAP are better than those of the SAP. The antioxidant test results show that the hydroxyl radical scavenging and reducing powers of the UAP are superior to those of the SAP. This study shows the composition, physicochemical properties, and antioxidant activity of A. arguta pectin extracted by the ultrasonic-assisted extraction method to provide a theoretical basis for its application as an antioxidant and other food additives in the food industry.

Comparison on emulsifying and emulgelling properties of low methoxyl pectin with varied degree of methoxylation from different de-esterification methods

Low methoxyl pectin (LMP) with different degree of methoxylation (DM, 40-50 %, 20-30 % and 5-10 %) were prepared from commercially available citrus pectin using high hydrostatic pressure assisted enzymatic (HHP-pectin) and traditional alkaline (A-pectin) de-esterification method. The results showed that both de-esterification methods and DM exhibited LMPs with varied physicochemical, structural, and functional properties. As the DM decreased, LMP showed a decrease in molecular weight (Mw), while an increase in negative charges and rhamnogalacturonan I (RG-I) ratio, accompanied with better emulsion stability, emulsion gel strength and water-holding properties. Relative to A-pectin, HHP-pectin had higher Mw and lower RG-I side chain ratio, contributing to its better thermal stability, apparent viscosity, and emulgelling properties. HHP-pectin with lower DM (5-10 %) showed superior thickening, emulsifying and emulgelling properties, while that with higher DM (40-45 %) had superior thermal stability, which provided alternative for de-esterification and targeted structural modification of pectin.

Development and Evaluation of a Stable Oil-in-Water Emulsion with High Ostrich Oil Concentration for Skincare Applications

This study investigates the development of an oil-in-water (O/W) emulsion enriched with a high concentration of ostrich oil, recognized for its abundant content of oleic acid (34.60 ± 0.01%), tailored for skincare applications. Using Span and Tween emulsifiers, we formulated an optimized emulsion with 20% w/w ostrich oil and a 15% w/w blend of Span 20 and Tween 80. This formulation, achieved via homogenization at 3800 rpm for 5 min, yielded the smallest droplet size (5.01 ± 0.43 μm) alongside an appropriate zeta potential (-32.22 mV). Our investigation into the influence of Span and Tween concentrations, types, and ratios on the stability of 20% w/w ostrich oil emulsions, maintaining a hydrophile-lipophile balance (HLB) of 5.5, consistently demonstrated the superior stability of the optimized emulsion across various formulations. Cytotoxicity assessments on human dermal fibroblasts affirmed the safety of the emulsion. Notably, the emulsion exhibited a 52.20 ± 2.01% inhibition of linoleic acid oxidation, surpassing the 44.70 ± 1.94% inhibition observed for ostrich oil alone. Moreover, it demonstrated a superior inhibitory zone against Staphylococcus aureus (12.32 ± 0.19 mm), compared to the 6.12 ± 0.15 mm observed for ostrich oil alone, highlighting its enhanced antioxidant and antibacterial properties and strengthening its potential for skincare applications. The optimized emulsion also demonstrates the release of 78.16 ± 1.22% of oleic acid across the cellulose acetate membrane after 180 min of study time. This successful release of oleic acid further enhances the overall efficacy and versatility of the optimized emulsion. Stability assessments, conducted over 6 months at different temperatures (4 °C, 25 °C, 45 °C), confirmed the emulsion's sustained physicochemical and microbial stability, supporting its promise for topical applications. Despite minor fluctuations in acid values (AV) and peroxide values (PV), the results remained within the acceptable limits. This research elucidates the crucial role of emulsification in optimizing the efficacy and stability of ostrich oil in skincare formulations, providing valuable insights for practical applications where stability is paramount.

Structural, chemical and technofunctional properties pectin modification by green and novel intermediate frequency ultrasound procedure

The impact of intermediate frequency ultrasound (IFUS, 582, 864 and 1144 kHz), mode of operation (continue and pulsed) and ascorbic acid (Aa) addition on the structural, chemical and technofunctional properties of commercial citrus high methoxyl-grade pectin (HMP) was investigated. The chemical dosimetry of IFUS, monitored by the triiodide formation rate (I3-), demonstrated that the pulsed ratio (1900 ms on/100 ms off) at the three frequencies was similar to that of continue mode but IFUS1144 kHz produced more acoustic streaming demonstrated by the height liquid measured using image analysis. In presence of Aa, HMP presented higher fragmentation than in its absence. IFUS did not give rise any changes in the main functional groups of the HMP. In general, a reduction in molecular weight was observed, being the presence of Aa the most influencing factor. Regarding monosaccharides, IFUS modified the structure of homogalacturonan and rhamnogalacturonan-I and increased of GalA contents of the HMP in presence of Aa at the above three frequencies. A reducing of the consistency index (k) and increasing of the flow index (n) of HMP were showed by IFUS frequency and Aa addition. The emulsifying activity and stability index were increased for HMP treated by IFUS in continue mode at all frequencies and in presence of Aa. The results presented in this research shown the effectiveness of IFUS as tool to modify pectin into different structures with different functionalities.

Smart Emulsions Stabilized by a Multi-headgroup Surfactant Tolerant to High Concentrations of Acids and Salts

Retaining emulsions stable at high acidity and salinity is still a great challenge. Here, we report a novel multi-headgroup surfactant (C3 H7 -NH+ (C10 COOH)2 , di-UAPAc) which can be reversibly transformed among cationic, anionic and zwitterionic forms upon pH variation. Stable oil-in-dispersion (OID) emulsions in strong acidity (pH=2) can be co-stabilized by low concentrations of di-UAPAc and silica nanoparticles. High salinity at pH=2 improves the adsorption of di-UAPAc on silica particles through hydrogen bonding, resulting in the transformation of OID emulsions into Pickering emulsions. Moreover, emulsification/demulsification and interconversion between OID and Pickering emulsions together with control of the viscosity and droplet size can be triggered by pH. The present work provides a new protocol for designing surfactants for various applications in harsh aqueous media, such as strong acidity and high salinity, involved in oil recovery and sewerage treatments.

Supramolecular structure of banana peel pectin and its transformations during extraction by acidic methods

In this study, the approaches to describe the mesh structure in the homogalacturonate domains of pectin and the effect of the native structure violations on the stabilization effectiveness of the oil-in-water emulsion were demonstrated. Pectin with a native structure was isolated from banana peel by enzymolysis of insoluble dietary fibres. This pectin was compared with pectins, which were isolated using hydrochloric and citric acids. The properties of pectins were analyzed taking into account the ratio of galacturonate units in nonsubstituted, methoxylated and calcium-pectate forms. The content of calcium-pectate units determines the density of inter-molecular crosslinking formation. The simulation results reflect the structure of rigid "egg-box" crosslinking blocks and flexible segments formed in native pectin mainly by methoxylated links. Hydrochloric acid extraction is accompanied by the destruction of the crosslinking blocks and depolymerization of pectin. Citric acid partially demineralizes the crosslinking blocks contributing to the release of macromolecular chains that do not have calcium-pectate units. The granulometric data indicates that the individual macromolecules take the thermodynamically stable form of a statistical tangle. Such conformation is an ideal basis for the formation of "host-guest" microcontainers having a hydrophilic shell and a hydrophobic core with an oil-soluble functional substance.

Jabuticaba (Plinia sp.) Peel as a Source of Pectin: Characterization and Effect of Different Extraction Methods

The peel of jabuticaba, a small fruit native to Brazil, has been shown to be a potential source of antioxidants and soluble dietary fibers. In this study, flours prepared from these peels were evaluated as a source of pectin. Different extraction methods were employed: ultrasound (US) extraction followed by low temperature heating (40 °C); in a microwave (MW) without (method 1) or with cellulase (method 2) or hemicellulase (method 3); or in a water bath (method 4). Pectin yields ranged from approximately 18% for methods 1 and 4 up to 22% for enzyme-assisted extractions (methods 2 and 3). Methods that did not employ enzymes resulted in low amounts of methoxyl pectins, as opposed to high amounts of methoxyl pectins obtained after enzyme treatment. Cyanidin-3-O-glucoside (C3G) and ellagic acid were the main phenolic compounds found in jabuticaba peel pectins, with higher C3G levels obtained with enzyme-free extraction (methods 1 and 4). All pectins from jabuticaba peel presented a reddish tone, good emulsifying properties and high swelling capacity. The pectin extracted using US+MW+cellulase (method 2) presented better emulsifying performance (higher values of emulsifying activity and emulsion stability), more effective than commercially available citrus pectin.