Table 2.

Interaction mechanism and the main properties of systems of pectin with different components.

Components	Interaction Mechanism	The Main Properties of the Complex	References
Avicel cellulose	By pectin side chains—arabinans and galactans; possible formation of hydrogen bonds	Low reversibility of complex	[116]
Sugar-beet microfibrillated cellulose	By pectin side chains	Enhancement of viscoelastic properties of cellulose suspension	[118]
Ferulic acid/protein	Covalently linked to pectin side chains, mainly to arabinose and galactose residues (in sugar beet cell wall)	Improvement in emulsifying ability and stability, surface activity of sugar beet pectins	[131]
Protein	Maillard reaction: carbonyl group of a reducing sugar residue of pectin reacting with an amino group of protein	Changes in solubility; amphiphilic character; high molecular weight; better emulsification properties	[136]
Starch	possible enhancement of pectin network through ionic interactions	Increase in the viscoelasticity, values of starch pasting parameters and extrusion parameters	[144,145]
Chitosan	Formation of a polyelectrolyte complex: electrostatic interaction between oppositely charged groups (pectin: COO−, chitosan: NH3+); other possible interactions: hydrogen bonds, coordinate bonds, van der Waals interactions and hydrophobic forces	Homogeneous PEC films; degradation of PEC films at lower temperature than decomposition of chitosan (thermogravimetric analysis)	[147,148]
Chitosan + calcium ions or NHS/EDC	Calcium ions as crosslinking agents of pectins; NHS/EDC: formation of covalent bonds between pectin and chitosan	Higher tensile strength of membranes and lower water uptake ability	[153]