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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]

Abstract Blueberry powder was sequentially fractionated to water (WSF), chelator (CSF) and sodium carbonate (NSF) soluble fractions. Uronic acid content was above 22 μg/mg AIS. The 4% potassium hydroxide (4KSF) and 24% potassium hydroxide (24KSF) soluble fractions were hemicellulose rich fractions. Cell wall glycan-directed monoclonal antibodies (mAbs) based glycome profiling analyses revealed that WSF, CSF and NSF fractions had epitopes of homogalacturonan (HG), arabinogalactan (AG), and xyloglucan (XG), but no xylan. 4KSF and 24KSF fractions had higher abundance of xyloglucan and xylan epitopes in addition to pectic epitopes. Arabinose and galactose were the two major neutral sugars in the WSF, CSF, and NSF. Xylose represented about 70 mol% neutral sugar in 4KSF and 24KSF fractions. Increased flexibility and presence of protein likely influence the propensity of pectin to bind anthocyanins. Graphical abstract Image 1 Highlights • Water soluble blueberry fraction has lower than 50% DE. • Water soluble fraction is rich in xyloglucans, low in homogalactan. • Chelator soluble fraction is rich in xyloglucan, rhamnogalactan and xylan. • Protein content is higher in alkali soluble fraction. • Increased protein and flexibility of pectin may increase anthocyanin binding. [ABSTRACT FROM AUTHOR]