Improved Extraction of Soluble Solids from Some Brazilian and North American Fruits

Pressurized liquid extraction using an accelerated solvent extractor (ASE) and dry methanol at 100 degrees C and 10 MPa pressure (1500 psi) can solubilize more solids than extractions done at ambient temperature and pressure. The percentages of soluble solids that were extracted from lyophilized acai (Euterpe oleracea), black olives (Olea europaea), elderberries (Sambucus nigra subsp. canadensis), noni (Morinda citrifolia), soursop (Annona muricata), atemoya (A. squamosa x A. cherimola), sugar apple (A. squamosa), biriba (A. mucosa) and pawpaw (Asimina triloba) fruit pulps were 22.3, 0.90, 52.7, 32.0, 93.6, 84.7, 92.5, 92.3 and 59.3%, respectively. About 26.2% of lyophilized atemoya seeds were solubilized. The percentages of soluble solids that were extracted from lyophilized mangosteen (Garcinia mangostana) mesocarps and peels were 53.1 and 34.2%, respectively. The percentages of soluble solids that were extracted from lyophilized mango (Mangifera indica) and Spanish plum (Spondias purpurea) peels were 85.7 and 65.1%, respectively. NMR analysis of the extracts indicated that not just fructose, but also glycoside fatty acid esters were present. So, the nutrient and caloric contents of these fruits and peels may be underestimated in the existing literature. On the other hand, almost none of the triglycerides present in acai and black olives were solubilized by methanol, making the extracts suitable for LC-MS analysis.