Production of Bixin-Rich Extracts From Annatto Seeds via Ethanol-Water Extraction Integrated With Ultrafiltration Technology.

This study investigated the extraction and concentration of bioactive compounds from annatto seeds by integrating ethanol-water extraction with ultrafiltration technology. The co-extraction of phenolic and carotenoid compounds was achieved by employing a mixture of ethanol and water as solvent. The annatto seed extract presented bixin and total phenolics at concentrations of 1.91 ± 0.02 and 52.31 ± 2.45 mg GAE g-1 (dry basis), respectively. Subsequent ultrafiltration through a 5 kDa membrane effectively concentrated the target molecules, with a membrane rejection of 47.53 ± 0.22% for total phenolic and 97.90 ± 0.02% for bixin molecules. Initial permeate flux was 28.59 L h-1 m-2, stabilizing at a steady-state flux of 9.26 L h-1m-2. The observed flux decline was predominantly characterized by a cake formation fouling mechanism at the earlier times of filtration, while the final flux was described by both cake formation and pore blockage mechanisms. This work highlights the potential of membrane technology for producing high-quality annatto extracts, promoting their broader industrial application.