Morphological, physicochemical, techno-functional, phytochemical, and antioxidant evaluation of polyembryonic and non-polyembryonic maize sprouts

The growing demand for foods with better characteristics has led to the search for new alternatives, one of these being sprouts, of which polyembryonic maize kernels have been little studied. The objective of this work was to evaluate the morphological changes, as well as the physicochemical, techno-functional, phytochemical, and antioxidant properties of polyembryonic (Pem) and non-polyembryonic (NPem) corn sprouts at different germination times (0, 5, 10, and 15 days). Different analytical techniques as well as “green” extraction technique (Microwave-ultrasound) with various solvents were used to obtain phytochemicals. PEm “normal high polyembryony” (NAP) and NPEm “landrace” (CRO) maize showed higher growth (up to 24.7 and 30.6 cm) and moisture content (up to 89.5 and 87.7%). Overall protein content increased by up to 51% relative to the initial value, with higher PEm content (15.0 and 14.5% in “brachytic high polyembryony” (BAP) and NAP maize respectively). Fibre and protein content were negatively correlated with starch content. Likewise, the techno-functional properties improved, with higher values for NAP, BAP and CRO at 10 and 15 days of germination. PEm presented higher yields (13 times higher), higher content of hydrolysable polyphenols (553.08 ± 44.68 mg/100 g (BAP)) at 1/16 concentrations of 70% EtOH, and higher content of condensed tannins (1623.38 mg/100 g (NAP)) at 1/8 and 30% EtOH concentrations. Finally, PEm showed higher antioxidant activity which can be attributed to the content and presence of different polyphenols. The results indicate that sprouts produced from polyembryonic maize kernels present better physicochemical, phytochemical, techno-functional and antioxidant properties. •Germination increases components that improve techno-functional properties.•15-day germination increases protein-rich tissue production by up to 50%.•Polyembryonic sprouts contain up to 9 times more polyphenols than non-polyembryonic.•Extractions with polyembryonic sprouts show yields between 1.37 and 2.86%.•Sprout extracts 1/12 (m/v) with EtOH 30% showed higher antioxidant activity.