Data of β-carotene nanoemulsions co-ingested with oatmeal in terms of viscosity , pH, lipid digestibility and bioaccessibility

Each Excel file contains a brief description of the data. The initial and each gastric empting (GE) viscosities of nanoemulsion (NE) and nanoemulsion-oatmeal (NO) were measured using SV-10 vibro-viscometer equipment (A&D Company, Tokyo, Japan). Once calibrated, the equipment applies a vibration of 30 Hz of constant amplitude (0.4 mm) to the sample into the holder, thus measuring fluids susceptibility to deformation. The results were expressed in mPa.s.
To calculate the lipid digestibility during the in vitro small intestinal digestion, the pH was always maintained at 7.0 by adding dropwise a NaOH solution (0.25 M) to compensate for acidity generated by free fatty acids (FFAs) released during lipid digestion. Calculating the lipid digestibility defined by the percentage of free fatty acids (FFAs) released was done by recording the volume of NaOH (0.25 M) in the small intestinal digestion of each GE over 120 minutes.
The bioaccessibility of each GE of NE and NO was assessed by centrifuging an aliquot of the digest at 15,000 rpm for 40 minutes at 8°C using a Mikro 220R centrifuge (Hetrich, Germany). The supernatant was collected containing mixed micelles in which the β-carotene was solubilized. 0.5 mL aliquot of the initial nanoemulsion-containing oatmeals and the micellar fraction was mixed with 2 mL of ethanol and 3 mL of hexane and vortexed for 10 s. Afterwards, the upper hexane phase containing the β-carotene was transferred to a test tube and the extraction was repeated two times until the ethanol lower layer was clear. The hexane fraction was analysed spectrophotometrically (Jasco, V-670, Japan) at 450 nm.