Green coffee nanoparticles: optimisation, in vitro bioactivity and bio-release property

Nanoencapsulation by spray drying was performed to protect and preserve antioxidant rich dietary polyphenols from green coffee beans. Nano-encapsulation of green coffee was done using maltodextrin as wall material. The nanoparticles were further characterised by zetasizer, differential scanning colorimetry, X-ray diffraction, In vitro gastric intestinal studies and storage stability. Optimal nanoparticles were obtained at a drying temperature of 125 degrees C and 2:1 Mwall/Mcore ratio (10% w/w maltodextrin), provided better encapsulation yield (40% w/w) and 70 +/- 5% (w/w) encapsulation efficiency with 82.34 nm particle size, -28.8 mV zeta-potential. The In-vitro bioactivity of nanoparticles ensured 80 +/- 2% (w/w) of chlorogenic acid availability in a controlled release in the intestine. Storage stability of nanoparticles under varied temperature was remarkably improved compared to non-encapsulated green coffee extract. However, the results indicated that the potential benefits of using maltodextrin coated green coffee nanoparticles for controlled release of Chlorogenic acid and sufficient antioxidative protection during prolonged period.