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Protein rich (F1) and protein poor (F4) fractions of sugar beet pectin (SBP). Protein rich F1, protein poor F4, and control SBP were used to make oil-in-water emulsions with 0.5% or 1.5% SBP (F1_0.5, F1_1.5, F4_0.5, F4_1.5 or C_1.5) and 15% (medium chain triglyceride) MCT oil and emulsifying activity was determined. Changes in D[4,3], light microscopy and rheological parameters during storage at 32 °C for 10 days indicated that SBP fraction and concentration influenced emulsion stability. Emulsions prepared with 0.5% fraction F4_0.5, with lower protein and surface hydrophobicity, had a D[4,3] values less than 1 μm, which remained the same during storage. D[4,3] values of emulsions, prepared with the 1.5% fraction F1_1.5 with higher protein and surface hydrophobicity, increased from 1.42 to 2.09 μm at 10 d. Emulsions prepared with unfractionated control SBP were intermediate in particle size. Emulsions prepared with F4_1.5 and F1_0.5 had higher D[4,3] values of 3.45 and 4.18 μm after 10 d, respectively. There were no significant changes in viscosities of individual emulsions over 10 days. Emulsions were shear thinning or near Newtonian. Protein poor Fraction F4 with greater hydrophile/lipophile ratio formed more stable emulsions at 0.5%, but not at 1.5%, compared to protein rich Fraction F1 at 1.5%. [ABSTRACT FROM AUTHOR]

Pectin is a complex structural polysaccharide located in the cell wall and middle lamella of higher plants. The homogalacturon (HG) regions may be methyl esterified or de-esterified to create a block co-polymer structure. The HG backbone may be interrupted by neutral sugar side chains forming the rhamnogalacturon I (RGI) region, or rhamnogalacturon II (RGII), a conserved structure. In addition, protein, ferulic acid and acetyl groups may be found on some sources of pectin. While pectin has positive health effects against many diseases related to inflammation and as a delivery vehicle for bioactives for colon targeted delivery, conflicting results are reported and may be related to paucity of physico-chemical information or source of pectin. Pectin structure can be enzymatically or chemically modified to produce molecular fragments that can be used to successfully entrap phytochemicals for emulsion based targeted delivery to the colon. Likewise, charge modified pectin allows the development of delivery systems based on hydrogel technology. Pectin is recognized as a soluble dietary fiber, and likely has multiple outcomes against cardiovascular disease. More recent evidence also points to the role of neutral sugars, arabino-oligosaccharides, and ferulic acid and other phenolics associated with pectin as a dietary fiber and in vitro fermentability of selected domains of pectin and associated colonic metabolites on inflammation and gut health. While the mechanism of the positive effects of pectin remain to be elucidated, emerging evidence points to synergism between specific domains of pectin structure and other food constituents. [ABSTRACT FROM AUTHOR]

Sugar beet pectin (SBP) and β-lactoglobulin (BLG) contain ferulic acid and tyrosine, respectively, potential substrates for laccase. Dispersions of BLG were treated with laccase and/or heat and SBP to assess potential for ferulic acid in SBP to influence laccase conjugation of BLG. Changes were investigated by size exclusion chromatography combined with multi angle laser light scattering (HPSEC-MALLS), refractive index (RI) and UV detector, particle size and ζ-potential analysis. Molecular weight (MW) of BLG decreased from 3.7 × 104 to 2.9 × 104 and root mean square (RMS) decreased from 41 to 36 after laccase treatment. The slope of a conformation plot increased from 0.35 to 0.72, indicating a change in shape in laccase treated BLG to more random coil. While laccase did not affect MW of BLG, MW of BLG increased after sequential heat and laccase treatment to 2.9 × 106 and 4.4 × 106, respectively. Free thiol (SH) increased by heat and laccase treatment of BLG; tyrosine in BLG increased only by heat. An increased MW and decreased ferulic acid in SBP was observed in the presence of BLG and laccase. The increase in MW was attributed to entrapment of BLG in SBP cross-linked matrix catalyzed by laccase. [ABSTRACT FROM AUTHOR]

Laccase, an oxidative enzyme, was used to catalyze the hetero and homo covalent conjugation between ferulic acid in sugar beet pectin (SBP) and tyrosine in heated β-lactoglobulin (H_BLG). The conjugation of SBP and H_BLG was confirmed by peak position using size exclusion chromatography, multi angle laser light scattering, refractive index, and UV detection. H_BLG, pre-treated with laccase, eluted at an earlier volume with greater UV280 absorbance than non-laccase treated dispersions. Tyrosine decreased in H_BLG that contained laccase treated SBP samples. Heat enhanced exposure of tyrosine in BLG and improved conjugation with SBP by laccase. H_BLG·SBP conjugates with laccase had improved solubility than laccase untreated dispersions at pH values near the isoelectric point of BLG. [ABSTRACT FROM AUTHOR]

Abstract: Laccase catalyzes intermolecular cross-links between ferulic acid of sugar beet pectin (SBP). Conjugation of SBP by laccase was confirmed by increased molecular weight, monitored by size exclusion chromatography, combined with multi-angle laser light scattering (SEC–MALLS), by reduced ferulic acid concentration detected at UV 325 nm, as well as by increased particle size. In addition, cross-linked SBP developed a more compact, branched structure as verified by a smaller root mean square (RMS) when molecular weight increased. Emulsions prepared with conjugated SBP had significantly smaller d 4,3 diameter and uniform droplet size, with more negative ζ-potential than non-treated SBP, during 30 days storage at 37 °C. The d 4,3 diameter was 5.3 μm and 3.8 μm for SBP and conjugated SBP, respectively. Covalently conjugated SBP has increased functionality and improved emulsion stability, most likely attributable to development of thick layer at the oil interface. [Copyright &y& Elsevier]

Abstract: The interaction of non-fat dry milk, caseinate and casein (CSN) fractions with charge modified pectins (B-Pec and U-Pec) and unmodified pectin (O-Pec) in acidified dispersion systems was investigated. U-Pec led to more precipitation of proteins than O-Pec or B-Pec. Casein dispersions with pectin had larger particle size, especially U-Pec and B-Pec, than dispersions without pectin. Dispersions with charge modified pectins showed more negative ζ-potential than dispersions with unmodified pectin or dispersions without pectin. U-Pec enhanced negative ζ-potential of β-CSN more than B-Pec. There was no significant difference in flow behavior among non-fat milk samples regardless of pectins added. In contrast, non-Newtonian behavior, shear thinning behavior was observed in modified pectin added κ-CSN. Analysis by light microscopy of non-fat milk and κ-CSN showed that sizes and shapes were changed by addition of O-Pec and U-Pec. The results suggest a specific affinity between pectin and κ-CSN, which is related to the charge distribution of pectin. [ABSTRACT FROM AUTHOR]

Abstract: Pectin was de-esterified by U-PME or B-PME, pectinesterases that differed in cationic character and peptide composition. Pectin fractions of unmodified (O-Pec) and Valencia PME modified pectins (B-Pec and U-Pec) were separated by ion exchange (IEX) chromatography and characterized for calcium sensitivity by ζ-potential, texture profile analysis (TPA), and viscoelastic properties. U- and B-Pec had more negative ζ-potential than O-Pec, and became increasingly negative at higher pH values. Without CaCl2, viscosity of O-Pec was higher than B- and U-Pec. With 35mM CaCl2, B- and U-Pec gelled, but O-Pec did not gel. TPA values were not significantly different between B-Pec and U-Pec. The G'' values of O-Pec was 20–50-fold lower than G'' for B-Pec or U-Pec. After separation with ion exchange chromatography, later eluting fractions formed stronger gels than earlier eluting fractions. However, pectin fractions had lower viscosity and G'' values than unfractionated pectin, which is likely related to molecular weight differences. Results show that U-Pec forms stronger gels than B-Pec that is related to length of charge block and numbers of de-esterified pectin molecules. [Copyright &y& Elsevier]

Pectins from highbush blueberry powder were sequentially solubilized in water, chelator, and sodium carbonate solvents and precipitated (ADF.WSF, ADF.CSF, and ADF.NSF) or not precipitated in ethanol (DF.WSF, DF.CSF, and DF.NSF) before dialysis and freeze‐drying. Alcohol precipitation more effectively removed bound anthocyanins and low molar mass pectins from water‐ and chelator soluble fractions than dialysis alone. Blueberry water soluble fractions were high methoxyl pectins, rich in neutral sugars (36 to 38 mol%), and had high molar mass (7.01 × 105 to 2.71 × 106 g/mol). Blueberry chelator soluble fractions were low methoxyl pectins and rich in uronic acids (90 to 92 mol%) which were more linear and less branched structure than other fractions or commercial citrus pectin. The molar mass ranged from 1.59 × 106 to 2.06 × 106 g/mol. Water‐ and chelator soluble fractions exhibited pseudoplastic behavior (n < 1) at 1% dispersion. Blueberry sodium carbonate soluble fractions were rich in protein (18%) and neutral sugars (42 to 28 mol%), and had low molar mass (1.08 × 105 to 1.27 × 105 g/mol). Blueberry pectins have desirable physico‐chemical properties for use as functional ingredients in food or beverages. Practical Application: Alcohol precipitation effectively removed anthocyanins from the pectin. The characterization data provided the benefits of blueberry pectin as a functional ingredient. This study can be used by food or product developers who are interested in pectin from blueberries or other berry products. [ABSTRACT FROM AUTHOR]

Husk tomato ( Physalis ixocarpa Brot. var. Rendidora) waste was evaluated as a source of specialized pectin, and pectin extracted from this waste was characterized physicochemically. Fruit was blanched for 10 or 15 min and extracted in 0.1 N HCl for 15 to 25 min. Extracted pectin was subjected to physicochemical analysis. For all extraction conditions, the percentage of anhydrogalacturonic acid exceeded 60%, indicating that husk tomato was a good source of pectin. The degree of esterification of pectin molecules was 63% to 91%. The amount of extracted pectin decreased with increasing extraction time. The apparent viscosity of husk tomato pectin showed the characteristic behavior of pseudoplastic fluids. Neutral sugars were identified, and the amounts of 6 sugars (fucose, rhamnose, arabinose, galactose, glucose, and xylose) were quantified. Sugars identified in husk tomato pectin and present in the Rhamnogalacturonan I region, arabinose, galactose, and rhamnose suggest a highly branched structure, which will influence its future applications. Molecular weight values were 542 to 699 kDa, exceeding molecular weight values reported for commercial citrus pectins from 134 to 480 kDa. The extraction process significantly ( P < 0.05) influenced the physicochemical properties of pectin. Up to 19.8% from the total amount of pectin in the husk tomato was extracted by 10 min of blanching and 20 min of a more heat treatment. Our findings indicate that husk tomato can be a good alternative source of pectin having highly distinctive physicochemical characteristics. [ABSTRACT FROM AUTHOR]

Abstract: The physical and chemical properties of commercial low methoxyl citrus pectins, CP 28 and CP 55, and a pectinmethylesterase (PME) charge modified citrus pectin (MP 38) were compared, and the differences in ability to encapsulate indomethacin in hydrogel beads was determined at 0.5 or 1.0% (w/v) indomethacin ratio, and 100, 200 or 300mM CaCl2 solution. In order to investigate the drug release characteristics, indomethacin loaded dried hydrogel beads were immersed in simulated gastric fluids (pH 1.2) for 2h, followed by immersing in simulated intestinal fluids (pH 7.4) for 3h. Pectin type was highly significant (p <0.0001) for encapsulation efficiency and in vitro release assay. Encapsulation efficiency was also highly affected (p <0.0001) by indomethacin ratio and CaCl2 concentration. The accumulative release rate of indomethacin from pectin hydrogel bead was less than 15% in simulated gastro-intestinal fluids. MP 38 beads showed significantly higher entrapment efficiency and lower release rate than beads formed from CP 28 or CP 55. MP 38 hydrogel formulated with 300mM CaCl2 and 0.5% indomethacin ratio showed the highest entrapment efficiency. These studies suggest that charge modification of pectin improves encapsulation efficiency of drugs for colon targeted drug delivery system through oral administration. [Copyright &y& Elsevier]

Abstract: W/O/W double emulsions (DEs) stabilized by charged soluble complexes of whey protein isolate (WPI) and modified pectins were investigated in relation to their stability and the release of two types of electrolytes, NaCl and sodium ascorbate. WPI alone cannot properly stabilize the DEs. The droplet size is relatively large (100μm) and increases with time. However, addition of modified pectin to form a soluble complex with WPI significantly improved the stability. DEs prepared with two types of oils (medium chain triglycerides (MCT) and R(+)-limonene) were studied by measuring droplet size, creaming, viscosity, and electrolyte release. Irrespective of their very different oil phase nature, both emulsions were stable against coalescence, but R(+)-limonene formed smaller droplets (25μm) than MCT (35μm). The electrolyte release rate was significantly higher from the R(+)-limonene that formed DEs with much lower viscosity. R(+)-limonene-DE released 75% of the NaCl after 28 days, while MCT-DE released only 50%. NaCl was released more slowly than sodium ascorbate. Apparently, the release mechanism from R(+)-limonene-DE was found to be “thinning the outer interface and release of the entire inner droplets” while it seems that the release from MCT-DE was slower and “diffusion controlled”. DEs stabilized by WPI/C63 released 12% of the sodium ascorbate after 1 day in milk and remained stable for at least 8 days. However, DEs stabilized with only WPI released about 50% of the sodium ascorbate after 1 day, and phase separated after 8 days. [Copyright &y& Elsevier]

Abstract: Valencia pectinmethylesterase (PME) fractions, B-PME, containing 36 and 13kDa protein bands and U-PME, containing a 36 and 27kDa protein bands, were used to de-esterify original pectin (O-Pec) from 73% degree of esterification (%DE) to 63% (B-Pec) and 61% DE (U-Pec), respectively. Most O-Pec eluted from ion exchange chromatography at low salt concentration and a smaller component eluted at higher ionic strength. B-Pec and U-Pec eluted as one broad peak at higher ionic strength. PME modification did not change molecular weight: O-pectin (134,000g/mol), U-Pec (133,850g/mol), and B-Pec (132,250g/mol). The NMR signal of GG and GGG increased after modification, whereas the signal of EE and EEE decreased. The negative ζ-potential increased with pH for all pectins. U-PME and B-PME created differently modified pectins that vary in degree and length of multiple attacks and fraction of the pectin population that was modified. [Copyright &y& Elsevier]

The effect of pectin composition on the binding selectivity to anthocyanins was investigated by Langmuir isotherms with two blueberry pectins, water soluble fraction (WSF) and chelator soluble fraction (CSF). Adsorption was four times higher between CSF and anthocyanins, than WSF and anthocyanins. Higher adsorption was attributed to the more linear, more negatively charged homogalacturonan region of CSF, compared to the more branched, neutral sugar rich WSF. The CSF binding sites ( q m a x ) to anthocyanins were estimated at 1413–1904 μg/mg pectin, which was about eight times higher than WSF binding sites. No difference was observed in binding affinity (K L) among blueberry pectins. WSF, rich in neutral sugar side chains, showed lower and more variable interaction with anthocyanins. Binding studies also showed that blueberry pectin-anthocyanins adsorption was highest at pH 3.0 and lowest at pH 4.0. Increasing concentration from 25 to 200 mM citrate-phosphate (CP) weakened the pectin-anthocyanins interaction between pH values 3.0 and 4.0. However, no significant difference in binding was observed at pH 2.6 with increasing CP. As pH values changed from 4.0 to more acidic pH, electrostatic interaction decreased while hydrophobic interactions increased between blueberry pectin and anthocyanins, and hydrogen bond likely remained constant. Putative health benefits of anthocyanins are probably influenced by small pH and ionic strength changes in food matrixes. Image 1 • Binding sites and affinity of anthocyanins and blueberry pectins vary • Anthocyanins bound more linear and more negatively charged pectin structure • Increasing ionic strength weakens chelator fraction-anthocyanins interaction • Decreasing pH strengthens hydrophobic or π-interaction of pectin-anthocyanins [ABSTRACT FROM AUTHOR]

Native high methoxy citrus pectin (NP) was de-esterified by pectin methyl esterase to produce modified pectins [MP (42, 37, and 33)] having different degrees of esterification. Complex coacervation between a pea protein isolate (PPI) and each pectin was investigated as a function of pH (8.0–1.5) and mixing ratio (1:1–30:1, PPI-pectin). Complex formation was found to be optimal for biopolymer-mixing ratios of 8:1, 8:1, 25:1 and 25:1 for PPI complexed with NP, MP42, MP37 and MP33, respectively, at pHs 3.6, 3.5, 3.9 and 3.9. And, the critical pHs associated with complex formation (accessed by turbidity) was found to shift significantly to higher pHs as the degree of esterification of the pectin decreased, whereas the shift in the pH corresponding to their initial interactions was minimal with degree of esterification. Complexation of PPI with NP and MP42 greatly improved the protein solubility. • Pectin was enzymatically modified to have degrees of esterification of 33–42%. • Interactions between pea protein isolate and modified pectin were examined. • Optimal protein-pectin mixing ratios increased as DE values increased. • Protein solubility was enhanced with the addition of pectin (DE 42%). [ABSTRACT FROM AUTHOR]

• Malvidin-, cyanidin-, and delphinidin-3-glucosides uniquely bind pectin fractions. • In vitro stability was highest with chelator soluble fraction and cyanidin-3-glucoside. • Chelator soluble fraction protected anthocyanin stability more than water soluble fraction. • Hydrogen bond contributes strongly to blueberry pectin-anthocyanin interaction at pH 4.0. Pectin was extracted from blueberry powder as water soluble fraction (WSF), rich in branched regions, and chelator soluble fraction (CSF), linear, with strong negative charge. Binding of pectins with three anthocyanin standards (malvidin-3-glucoside; M3G, cyanidin-3-glucoside; C3G, and delphinidin-3-glucoside; D3G) and blueberry extract (BBE) were used. Without blueberry pectin, M3G was the most stable followed by C3G, whereas D3G completely disappeared after gastrointestinal digestion. CSF prevented M3G and C3G degradation more than WSF, the in vitro stability was highest with CSF and C3G. Increased stability of anthocyanins after simulated gastrointestinal digestion suggests that anthocyanins can be transported to colon where gut microbiota actively produce anthocyanin metabolites. The amount of bound anthocyanins that interacted with blueberry pectin increased as the number of hydroxyl groups increased on anthocyanins. Hydrogen bonding in addition to electrostatic interaction contribute to stability of pectin-anthocyanins interaction at pH 4.0 and contribute to stability under gastrointestinal simulation. [ABSTRACT FROM AUTHOR]

A rheological study was carried out to evaluate formulations of test dispersions and gels of high methoxyl pectins (HTHMP) obtained at different conditions from husk tomato waste ( Physalis ixocarpa Brot.). The effect of extraction agent (hydrochloric acid or citric acid), blanching time (10 or 15 min) and extraction time (15, 20 or 25 min) on the rheology of the tested samples was evaluated. Flow behavior and activation energy were evaluated on the test dispersions, while ( E a ) frequency sweeps, temperature sweep, creep-recovery test and penetration test were performed on the gels. HTHMP dispersions showed shear thinning flow behavior, while showing a good fit to Cross model. Extraction agent, blanching time and extraction time did not have effect on Cross parameters (η z , η∞, C, and m). E a decreased as blanching time and extraction time increased. Frequency sweeps revealed high dependence on frequency for both G’ and G”, while temperature sweeps (25- 95 °C) showed thermostable husk tomato pectin gels. Hydrocloric acid (HCl) extracted pectin gels showed stronger structure than citric acid (CA) gels. [ABSTRACT FROM AUTHOR]

BACKGROUND Preventing post-harvest waste of Palmyra palm ( Borassus aethiopum Mart.) fruits is possible by recovery of pectin as a value-added ingredient. Extraction conditions on yield and functionality of Palmyra palm pectin was determined at different temperatures and pH values with 30 min extraction time. RESULTS Palmyra palm fruits contain more than 650 g kg−1 galacturonic acid and produce soft gels with sucrose in acidic media despite a high degree of acetylation (∼5%). Mechanical deformation of pectin gel was similar when extracted at pH 2.5 and 70 °C or under natural pH at room temperature or 70 °C. Pectins isolated at pH 7 exhibited comparable gel softness ( G′/ G″) with commercial pectin. Palm pectins also showed emulsifying activity greater than 50%, attributed to high protein content of 8 g 100 g−1. For pectins extracted at pH near 5.2-5.5, molar mass ranged from 3.00 to 3.38 × 105 g mol−1; intrinsic viscosity ranged from 218 to 297 mL g−1; arabinose was the main neutral sugar; ζ-potential ranged from −23 to −25 mV. CONCLUSION Palm fruit offers an inexpensive raw material to extract pectin in environmentally friendly and economical way and yield a pectin with unique gelling, viscosifying and emulsifying properties. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Sugar Beet Pectin (BP) was sequentially fractionated with increasing isopropanol into six fractions from a commercial BP control (BP2–C) and denoted as BP2–F1 to BP2–F6. Fractions of BP2 were categorized based on physico-chemical characteristics of similar protein and ferulic acid content, varying galacturonic acid, surface hydrophobicity, degree of esterification and molecular weight. Glycan-directed monoclonal antibodies response showed intense binding for homogalacturonan, rhamnogalacturonan I and arabinogalactan epitopes that varied between early and later precipitating fractions, and between lots of BP. In a 14-day study of rice bran oil-in-water emulsion, the particle size (2 ± 0.3 μm) and ζ-potential (−34 ± 3 mV) remained stable for BP2–F3 and B2–F4. Fractions that precipitated at lower alcohol concentrations likely have more amphiphilic properties, compared to later precipitating fractions that provide more steric stabilization. [Display omitted] • Sequential isopropanol fractionation of beet pectin (BP) resulted in two populations. • Emulsifying stability was associated with amphiphilic BP and steric stabilization. • Glycome profiling provided comprehensive view of cell wall glycan epitopes. • Glycome profiles were unique for BP controls and fractions. [ABSTRACT FROM AUTHOR]

Abstract: The molecular weight (MW) distribution of whey proteins (WP) mixed with various pectins was investigated using size exclusion chromatography (HPSEC) combined with multi-angle laser light scattering (MALLS). Samples were prepared with 1, 2, 5, 8% WP and 1% pectin. Mixtures were studied at pH 6.0 and CaCl2 concentrations of 0, 5, 10mM. Aggregate formation was determined after heating at various temperatures. The interactions between WP and low methoxyl pectin were observed before heat treatment. In the absence of calcium, mixing pectins with WP increased the average molecular weight of the aggregates, but the degree of methoxylation of pectins did not affect the MW distribution of the aggregates. On the other hand, in the presence of calcium, low and high methoxyl pectins generated different molecular weight distributions. In addition, the presence of low methoxyl pectin seemed to have a protective effect on WP, as the aggregates showed a smaller molecular weight and a smaller peak. [Copyright &y& Elsevier]

Pectin is a co-product from juicing and the physico-chemical quality is important to functionality of pectin in food and pharmaceutical applications. Juice and peel from Huanglongbing (HLB) control and infected Valencia oranges were analyzed. Infected fruit had smaller diameter, lower L* and b* values and highly variable a* values. Juice from infected fruit had higher pectinmethylesterase (PME) activity of 1.5 Units/mL, which retained higher activity during 15 days of storage at 4 °C, and juice had higher cloud loss. Also, the juice obtained from infected fruit had lower °Brix (8.5–8.9), higher titratable acidity (0.71–0.88%), and lower pH (3.45–3.75). Molecular weights of 154–157 kDa and degrees of esterification of 65–67% were similar. Pectin yield from dried peel was reduced by 6% in infected fruit to 4.18 g/100 g. Total neutral sugars in pectin from control fruit were higher, 84.1 μg/mg, compared to infected fruit, 60.7 μg/mg. Glucose, galactose, and arabinose, were higher in control fruit, 25.0, 40.8, and 9.7 μg/mg, compared to 14.5, 27.4, and 8.3 μg/mg in infected fruit. Viscosity was 0.015 Pa s, in 1% pectin from control or infected fruit (p > 0.05). Juice quality, including cloud stability, was negatively impacted by HLB, however pectin functionality was minimally impacted. • Huanglongbing negatively impacts citrus juice ◦Bx, pH, titratable acidity, color. • Juice from infected fruit has higher pectinmethylesterase activity and cloud loss. • Lower yield of pectin from peel was obtained from infected fruit. • Pectin is similar in control or infected fruit. [ABSTRACT FROM AUTHOR]