Application of supercritical technology in the production of microparticles of bioactive compounds from apple pomace

Abstract

The study's objective was to evaluate the efficiency of supercritical assisted atomization (SAA) technology in encapsulating bioactive compounds extracted from apple pomace (AP), a by-product of the juice industry. Supercritical assisted atomization (SAA) was performed with extract to polymer ratios (1:5, 1:10, and 1:20), encapsulation used polyvinylpyrrolidone (PVP), and a sugar-removal method was applied. The results indicate that the 1:10 ratio presented superior results, with an average particle size of 1.67 ± 1.25 µm and a dispersion index 2.25. The antioxidant capacity was 2.55 µmol of Trolox/g of AP, and the content of phenolic compounds reached 2.18 mg of gallic acid equivalent (GAE)/g of AP. Despite reducing the bioactive compounds after encapsulation, the stability was significantly improved: 92 % of the antioxidant capacity and 99 % of the phenolic compounds were preserved after two months of exposure to light, while the non-encapsulated extract retained only 66 % and 71 %, respectively. HPLC analysis identified gallic acid (91.16–128.13 ppm) and ascorbic acid (111.12–153.67 ppm) as the main compounds. The work also includes the feasibility of this route as a strategy for sustainable valorization of apple pomace using the Path2Green metric to evaluate the process from the perspective of green chemistry. The sustainability assessment using the Path2Green method generated a score of 0.524, indicating the sustainable feasibility of the process. Encapsulation aimed to protect bioactive compounds, such as phenolics and antioxidants, from degradation, increasing their stability and bioactivity for applications in the food, pharmaceutical, and cosmetic industries.