Tween 80 and Soya-Lecithin-Based Food-Grade Nanoemulsions for the Effective Delivery of Vitamin D

Fortification of food and beverages with vitamin D is demanding due to its poor water solubility and oxidation, due to exposure to light and high temperature. The purpose of this research work was to formulate an effective food-grade delivery system for the incorporation of vitamin D into food products and beverages. Food-grade vitamin D nanoemulsions were successfully prepared using mixed surfactant (Tween 80 and soya lecithin) and ultrasonic homogenization techniques. Significant effects (p < 0.05) of temperatures (4 and 25 °C) and storage intervals (1 month) were observed on the turbidity and vitamin D retention. At the end of a 2 month storage, the droplet sizes of the nanoemulsion were 140.15 nm at 4 °C and 155.5 nm at 25 °C. p-Anisidine value of canola oil significantly reduced (p < 0.05) after its incorporation into nanoemulsions. The turbidity values of nanoemulsions increased with the increase in storage duration and temperature. These nanoemulsions remain stable against a wide range of temperatures (30-90 °C), pH values (2-8), ionic strengths (50-400 mM), and freeze-thaw cycles (4 cycles). At the end of 30 days of storage, vitamin D retentions were 74.4 ± 1.2 and 55.3 ± 2.1% in nanoemulsions stored at 4 and 25 °C, respectively. These results suggest that mixed-surfactant-based nanoemulsions are an effective delivery system for the incorporation of vitamin D into food and beverages to overcome the worldwide deficiency of vitamin D.