title: Microscopic evidence for Ca(2+) mediated pectin-pectin interactions in carrot-based suspensions.
abstract: This study explored the use of fluorescently labeled pectin to obtain evidence for Ca(2+) mediated pectin-pectin interactions in situ. Specifically, carrots were either blanched at low temperature (LTB) or blanched at high temperature (HTB) to activate or inactivate endogenous pectin methylesterase, respectively. Consequently, pectin in tissue particles of LTB and HTB carrots exhibited low degree of methylesterification (DM) and high DM, respectively. Pectin present in the LTB carrot serum exhibited a lower DM, was more branched, and showed a higher molar mass compared to HTB carrot serum pectin. Ca(2+) mediated pectin-pectin interactions were influenced by serum pectin molecular structure, increased with increasing pH and Ca(2+) concentration, and decreasing DM. Presence of more linear pectin in the serum created a competition, leading to less intense interactions between labeled pectin and pectin at tissue particle surfaces. Generally, the most intense Ca(2+) mediated pectin-pectin interactions were observed for pectin of LTB carrot particles.
authors.affiliation: Laboratory of Food Technology, Leuven Food Science and Nutrition Research Centre (LFoRCe), Department of Microbial and Molecular Systems (M(2)S), KU Leuven, Kasteelpark Arenberg 22, Box 2457, 3001 Leuven, Belgium.
authors.forename: Clare
authors.initials: C
authors.lastname: Kyomugasho
authors.affiliation: Laboratory of Food Technology, Leuven Food Science and Nutrition Research Centre (LFoRCe), Department of Microbial and Molecular Systems (M(2)S), KU Leuven, Kasteelpark Arenberg 22, Box 2457, 3001 Leuven, Belgium.
authors.forename: Katleen L D D
authors.initials: KL
authors.lastname: Willemsen
authors.affiliation: Laboratory of Food Technology, Leuven Food Science and Nutrition Research Centre (LFoRCe), Department of Microbial and Molecular Systems (M(2)S), KU Leuven, Kasteelpark Arenberg 22, Box 2457, 3001 Leuven, Belgium.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Christiaens
authors.affiliation: Laboratory of Food Technology, Leuven Food Science and Nutrition Research Centre (LFoRCe), Department of Microbial and Molecular Systems (M(2)S), KU Leuven, Kasteelpark Arenberg 22, Box 2457, 3001 Leuven, Belgium.
authors.forename: Ann M
authors.initials: AM
authors.lastname: Van Loey
authors.affiliation: Laboratory of Food Technology, Leuven Food Science and Nutrition Research Centre (LFoRCe), Department of Microbial and Molecular Systems (M(2)S), KU Leuven, Kasteelpark Arenberg 22, Box 2457, 3001 Leuven, Belgium. Electronic address: Marc.Hendrickx@biw.kuleuven.be.
authors.forename: Marc E
authors.initials: ME
authors.lastname: Hendrickx
mesh_terms: D018552:Daucus carota / Q000737:chemistry*; D008853:Microscopy / Q000379:methods*; D010368:Pectins / Q000737:chemistry*; D013535:Suspensions
chemical_list: D013535:Suspensions; D010368:Pectins
keywords: Ca(2+) mediated pectin–pectin interactions; Carrot; Degree of methylesterification; Labeled pectin