Young seedlings as potential protein sources: Changes during germination and in vitro digestion

This research focused on the evaluation of the impacts of germination time on protein characteristics of alfalfa and broccoli sprouts as well as their behavior during in vitro digestion to assess their potential as tailored protein source. The results indicated that germination for seven days increased the crude protein content by 14.65 % for alfalfa and 30.95 % for broccoli. It also broke down high molecular weight proteins and altered the levels and composition of free amino acids in the sprouts. Germinating alfalfa for four days and broccoli for five days resulted in the highest levels of free essential amino acids, measuring 38.80 ± 0.41 mg/100 g DW and 41.16 ± 1.82 mg/100 g DW, respectively. Alfalfa sprouts, following simulated digestion, showed a greater increase in soluble protein, higher protein digestibility, and higher free amino acid levels. Conversely, broccoli sprouts showed elevated total phenolic content, potentially influencing their protein digestibility and amino acid release. The varying amounts of free amino acids during germination provide an opportunity to tailor raw materials with specific protein characteristics. Additionally, the results of simulated digestion suggest the potential for combining sprout proteins or integrating them with other protein sources to create a high-quality alternative protein option. • Germination time altered the protein characteristics of alfalfa and broccoli sprouts. • There were peak yields for free essential amino acid content during germination. • Alfalfa exhibited higher protein bioavailability following simulated digestion. • Broccoli demonstrated enhanced antioxidant properties after simulated digestion. • Sprouts released diverse amino acids after simulated digestion.