Effect of sodium carboxymethyl cellulose on complex coacervates formation with gelatin: Coacervates characterization, stabilization and formation mechanism. (August 2017)

• Record Type: Journal Article
• Authors: Duhoranimana, Emmanuel; Karangwa, Eric; Lai, Lingfeng; Xu, Xing; Yu, Jingyang; Xia, Shuqin; Zhang, Xiaoming; Muhoza, Bertrand; Habinshuti, Ildephonse
• Is Part Of: Food hydrocolloids. Volume 69(2017)
• Page Start: 111
• Page End: 120
• Publication Date: 2017-08
• Subjects: Complex coacervation -- Gelatin -- Carboxymethyl cellulose -- Morphology -- ATR-FTIR -- Circular dichroism -- Conformational transition; Hydrocolloids -- Periodicals; Food additives -- Periodicals; Colloïdes -- Périodiques; Aliments -- Additifs -- Périodiques; Colloids; Food additives; Periodicals; Electronic journals; 664.06
• DOI: 10.1016/j.foodhyd.2017.01.035
• Languages: English
• ISSNs: 0268-005X

Abstract

Abstract: The complexation mechanism of gelatin (G) and carboxymethyl cellulose (CMC) and their coacervates formation process were studied as a function of pH and protein (Pr) to polysaccharide (Ps) mixing ratio (Pr:Ps). Three different CMCs were chosen (FL9, FH9 and FVH6) and five mixing ratio of 1:1, 6:1, 7:1, 8:1 and 9:1 (w/w), were studied to disclose their individual coacervates transition pattern for zeta potential, turbidity, morphology, size distribution and coacervates yield. The coacervates formation mechanism and stability of formed coacervates were examined using Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR), Circular Dichroism (CD), Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). Coacervates with better morphology, good size distribution and highest yield were observed with G-FL9 at mixing ratio of 7:1 and pH 4.40. The evaluation of coacervates formation mechanism showed that G molecules experienced a conformational change in its secondary structure from a flexible pattern to an ordered poly-proline II (PPII) helix. The vibrations of OH and NH bonds spectra at 3437 and 3449 cm −1, respectively for G/CMC coacervates, shifted to lower wave numbers due to the conformational changes of gelatin and CMC, during the coacervates formation. G/CMC complex coacervates were more thermally stable than individual gelatin. Therefore, these complex coacervates will be able to protect and deliver heat sensitive bioactives and food ingredients. Graphical abstract: Highlights: Gelatin and CMC coacervation optimum pH and gelatin to CMC ratio were 4.40 and 7:1. Gelatin and CMC exhibited conformational changes during coacervates formation. Gelatin-CMC complex coacervates were thermally stable.