Germination as a Sustainable Green Pre-Treatment for the Recovery and Enhancement of High-Value Compounds in Broccoli and Kale

Germination is widely recognized as an effective strategy to enhance the nutritional quality and reduce anti-nutritional factors in plant foods. This study evaluated the impact of germination on Cruciferous vegetables (family Cruciferae or Brassicaceae) broccoli and kale by assessing changes in proximate composition, macro- and microelement profiles, total and individual polyphenols, phytic acid content, antimicrobial activity, and structural characteristics using Fourier Transform Infrared Spectroscopy (FTIR) and Small- and Wide-Angle X-ray Scattering (SAXS/WAXS) analyses. Germination significantly increased protein content (30.33% in broccoli sprouts and 30.21% in kale sprouts), total phenolic content (424.40 mg/100 g in broccoli sprouts and 497.94 mg/100 g in kale sprouts), and essential minerals, while reducing phytic acid levels in both species (up to 82.20%). Antimicrobial effects were matrix-dependent, being detected in broccoli and kale seed powders, while no inhibitory activity was observed for the corresponding sprout powders under the tested conditions. FTIR spectra indicated notable modifications in functional groups related to carbohydrates, proteins, and phenolic compounds, while SAXS analysis revealed structural reorganizations at the nanoscale. Overall, germination improved the nutritional and phytochemical quality of broccoli and kale while decreasing anti-nutritional compounds, highlighting its potential to enhance the health-promoting value of Brassica sprouts.