Effect of a home-grown palm wood germination tray with lime oil on enhancing GABA and inhibiting foodborne pathogens in RTE sunflower sprout salad and its mode of action

Abstract

Cultivating fresh, safe sprouts at home has gained popularity for busy lifestyles. However, ready-to-eat (RTE) salads, often consumed raw, can be a source of foodborne illnesses. The objective of this study was to develop a germination tray made from palm wood containing lime oil (LO) at concentrations of 0.006%, 0.012%, 0.018%, and 0.024% to boost the production of γ-aminobutyric acid (GABA) during the germination of sunflower seeds to produce RTE fresh salad sprouts for home growing. The shelf life of RTE sprouts was then investigated during cold storage (4 ± 2 °C) for an additional 5 days. The results confirmed that the palm tray with 0.012% LO was the most effective in producing the highest GABA content (235 mg/100 g), total phenolic content (58 mg GAE/100 g), total flavonoid content (1934 mg QE/100 g), and antioxidant ABTS activity (155 mg TEAC/100 g) within 72 h of the germination process, approximately double that of the control. Additionally, components of LO (limonene 12%, citral 8%, eucalyptol 1%, and γ-terpineol 1%) were detected in the sprouts. These components were effective against the growth of Escherichia coli and Listeria monocytogenes in the sprouts by damaging the cell walls, causing nucleic acid leakage, and reducing biofilm production. The sprouts treated with LO in the tray extended the shelf life of RTE sprouts in cold storage by at least 5 days, compared to just 1 day for the control. These findings suggest that growing sprout seeds for ready-to-eat (RTE) salads at home using the developed palm tray containing LO can ensure safer salad production in house options and potentially be marketed for sale in supermarkets.