Mechanistic Insights Into the Controlled Release and Antioxidant Protection of Neolamarckia cadamba Bioactives in...

Fortification of functional dairy products with botanical bioactives is constrained by the inherent bitterness and chemical instability of plant extracts. This study investigated the microencapsulation of Neolamarckia cadamba (Kadam) bark extract for incorporation into probiotic yogurt, targeting preserved antioxidant activity and enhanced sensory acceptability. Ultrasonication-assisted extraction in a 1:1 hydroethanolic system significantly outperformed conventional maceration in phytochemical recovery. The concentrated extract was spray-dried (inlet: 160°C; outlet: 80°C) using an optimized Quillaja saponin-sunflower lecithin carrier matrix, yielding spherical, fracture-free microcapsules with a principal intensity peak diameter of 78.98 nm (Z-average: 6183 nm, indicative of polydisperse aggregate populations in the feed emulsion), and a highly stable zeta potential of -38.3 mV. SEM imaging confirmed successful tannin sequestration within intact particles. Functional evaluation of the fortified probiotic yogurt demonstrated a total phenolic content of 71.47 mg/g and DPPH radical scavenging activity of 72.94%, both sustained throughout refrigerated storage. A 42-day release kinetics study confirmed controlled, gradual polyphenol diffusion into the yogurt matrix. Sensory panels awarded encapsulated formulations an overall acceptability score of 8.16 ± 0.36 out of 9, with no statistically significant differences observed between encapsulated and free-extract treatments for any sensory attribute (all p > 0.05), indicating comparable sensory acceptability. These findings establish encapsulated N. cadamba extract as a physicochemically stable, clean-label functional ingredient with improved antioxidant retention, favorable sensory acceptability comparable to free-extract formulations, and controlled polyphenol release in a probiotic yogurt matrix. In vitro digestion and in vivo bioavailability studies are warranted to fully substantiate health-efficacy claims.