Gumarabic -caseinate nanocomplexes bearing β-carotene (1): studying of complex formation by FTIR, DSC, turbidity and rheology

In this study, nano - complex production based on two biopolymers, casein and Arabic gum was studied for developing of a carrier system for β - carotene. For this purpose, complex formation was investigated by different techniques. The first the sodium caseinate solution sat 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 beta - carotene was loaded to the sodium casein solutions and Arabic Gum was added to it at different levels. The electrostatic interaction between biopolymers was induced by the adjustment of the pH.
The complex formation between two biopolymer and β carotene -caseinate was evaluated by Infrared spectroscopy (FT- IR), differential scanning calorimetry (DSC), turbidi ometry and rheometry. The FT- IR curves of nano - complexes showed that the spectrum of specific nano-complex containing beta-carotene in a given region of is different from the specific spectrum of every one of the biopolymers and beta-carotene. In the DSC test thermogram pattern of the biopolymeric nano-complex containing beta-carotene differed with the every one of single biopolymers and beta - carotene. This is possibly confirming the β - carotene encapsulation in nano - complexes. The results of turbidity measurement of solutions showed that the increasing of Arabic gum caused to increase in turbidity and maximum turbidity (134 NTU) observed in the casein ate 0.1 - Arabic Gum 1% (w/v).Investigating the rheological properties of nano - particles showed that increasing the concentration of Arabic gum from 0.1 to 1% caused to increase in the viscosity of aqueous nano-complex solutions which attributed to increasing of complex particle numbers.