Preparation and characterization of sodium caseinate-apricot tree gum/gum Arabic nanocomplex for encapsulation of conjugated linoleic acid (CLA)

Nanocomplexes (NCs) were formed through electrostatic complexation theory using Na-caseinate (NaCa), gum Arabic (GA), and Prunus armeniaca L. gum exudates (PAGE), aimed to encapsulate Conjugated linoleic acid (CLA). Encapsulation was optimized using NaCa (0.1 %–0.5 %), GA/PAGE (0.1 %–0.9 %) and CLA (1 %–5 %), and central composite design (CCD) was employed for numerical optimization. The optimum conditions for NC containing GA (NCGA) were 0.336 %, 0.437 %, and 3.10 % and for NC containing PAGE (NCPAGE) were 0.403 %, 0.730 %, and 4.177 %, of NaCa, GA/PAGE, and CLA, respectively. EE and particle size were 92.46 % and 52.89 nm for NCGA while 88.23 % and 54.76 nm for NCPAGE, respectively. Fourier transform infrared spectroscopy (FTIR) indicated that CLA was physically entrapped. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) confirmed the electrostatic complex formation. The elastic modulus was predominant for NCGA and NCPAGE dispersions while the complex viscosity of NCPAGE suspension was slightly higher than that of NCGA. The CLA in NCGA-CLA and NCPAGE-CLA exhibited higher oxidative stability than free CLA during 30 days of storage without a significant difference between the results of CLA oxidative stability tests obtained for NCs. Consequently, NCPAGE and NCGA could be applied for the entrapment and protection of nutraceuticals in the food industry.