Flavour profiles, antioxidant activity, particle size distribution and functional properties of some ethnic spice seed powder used as food additive

Spices are ingredients used to flavour, season and preserve foods besides their medicinal properties and health benefits. The flavour profiles, antioxidant activity, particle size distribution and functional properties of six underutilized ethnic spice's seed powder were determined by standard methods. GC–MS analysis revealed significantly higher (p < 0.05) concentrations of flavour compounds which were coumarin (Irugege), arachidonic acid (Gbafilo), linoleic acid (Njangsa), oleic acid (Omilo), 9-tetradecenal (Ataiko), and tocopherol and squalene (Country onoins). Tocopherol was significantly (p < 0.05) higher in Njangsa, Omilo and Country onion, whereas linoleic acid was higher in Irugege, Njangsa and Country onions. Further, the results revealed that total phenolic content was higher in Ataiko (17.42 mg GAE/100 g) and total flavonoids content was higher in Gbafilo (80.46 mg QE/100 g). DPPH percentage ranged from 39.27 (Njangsa) to 52.07 % (Country onions), FRAP was 28.69 (Omilo) to 42.02 Mmol Fe (11)/100 g (Ataiko). The spice's particle sizes were equivalent of 0.25 to 0.5 mm sieve mesh. Water and oil absorption capacities ranged from 0.9 (Njangsa) to 2.2 % (Irugege) and 1.1 (Njangsa) to 1.46 % (Omilo). Bulk density of spices varied between 0.37 to 0.61 g/cm³ (loose bulk density) and 0.55 to 0.96 g/cm³ (tapped bulk density). These spices represent natural sources of potent flavour and antioxidant compounds for nutrition and health benefits. The study further highlighted that the spices can play functional role in food systems and for industrial exploitation.