Improving solubility and stability of β-carotene by microencapsulation in soluble complexes formed with whey protein and OSA-modified starch.

Affiliation

Lin Q(1), Wu D(2), Singh H(2), Ye A(3).
Author information:
(1)School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, Zhejiang 310018, China; Riddet Institute, Massey University, Private Bag 11 222, Palmerston North 4442, New Zealand.
(2)Riddet Institute, Massey University, Private Bag 11 222, Palmerston North 4442, New Zealand.
(3)School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, Zhejiang 310018, China; Riddet Institute, Massey University, Private Bag 11 222, Palmerston North 4442, New Zealand. Electronic address: [Email]

Abstract

In this study, a soluble complex formed between 0.5% (w/v) heated whey protein isolate (HWPI) and 5% (w/v) octenyl succinic anhydride (OSA)-modified starch at pH 4.5 was used to encapsulate β-carotene for improving its solubility and stability. The apparent aqueous solubility of β-carotene was increased markedly (264.05 ± 72.53 μg/mL) after encapsulation in the soluble complex. Transmission electron microscopy and scanning electron microscopy were used to evaluate the effect of the encapsulation of β-carotene on the structure of the soluble complex. Fourier transform infrared spectroscopy showed that the characteristic peaks of β-carotene disappeared in the soluble complex, suggesting that β-carotene may have been encapsulated into the soluble complex via hydrophobic interactions. X-ray diffraction indicated that the β-carotene was in an amorphous form within the soluble complex. An accelerated stability test showed that the soluble complex could effectively improve the chemical stability of β-carotene during long-term storage under low pH conditions.