Gum arabic- caseinate nanocomplexes bearing β-carotene (2): Studying of particle size distribution, zeta potential, morphology and encapsulation efficiency

In this study, properties of caseinate-Arabic gum based nanocomplexs (produced by coacervation method) and encapsulation efficiency of β-carotene were investigated. For this purpose, complex formation was investigated by different techniques. The first, sodium caseinate solutions at the levels of 0.1 and 0.5 (w/v%) and Arabic gum at three levels of concentrations 0.1, 0.5, and 1% (w/v%) were prepared. Then β-carotene was loaded to the sodium casein solutions and Arabic Gum was added to them at different levels. The experimental tests showed that particle size and zeta-potential were affected by biopolymers ration and pH. The minimum particle size (95 nm) was observed at pH= 4.5 and in caseinate 0.1%-Arabic gum 0.5% solution however, maximum zeta-potential (-22mV) was observed at pH=5 in 0.1%-Arabic gum 0.1% solution. According to the images obtained from the scanning electron microscopy (SEM) the particles size of 0.1%-Arabic gum 0.5% nano-complex at pH=4.8 was about 100 to 200 nm and in the images obtained from transient electron microscopy (TEM), a nano-particle with core and the two layers wall was observed. The results showed that increasing of caseinate and Arabic gum concentration caused to increase and decrease of encapsulation efficiency, respectively.