PHYTOCHEMICAL PROPERTIES OF SELECTED HERBS USED IN NIGERIAN PEPPER SOUP AND THEIR EFFECT ON OXIDATIVE STABILITY OF CHEVON

Abstract

The phytochemicals properties of some selected Nigerian pepper soup herbs: Occimum gratissinum (Big leaf basil), Ocimum basilium (Small leaf basil), Aframonum melegueta (Grain of paradise or Melegueta pepper), Piper guineense (Ashanti and Guinea pepper), Zingiber officinale (Ginger), Xylopia aethiopica (African or Ethiopian pepper) and Tetrapleura tetraptera (Aidon fruit) were evaluated. The oxidative stability of cooked and refrigerated chevon treated with the herbs was also assessed. Tannin, saponins, flavonoids, cardiac glycosides, terpenoids, phytates, phenols and oxalate were identified in O. gratissinum, A. melegueta, P. guineense, Z. officinale, X. aethiopica T. tetraptera, and O. basilicum using standard procedures. Cardiac glycosides were not found in Ocimum basilicum. There were significant differences (P<0.05) in the yield of tannins, saponins, flavonoids and alkaloids across the selected herbs with values ranging between 1.21 - 8.91 mg/100g, 1.89 – 3.57%, 0.02 – 1.66 mg/100g and 1.56 – 3.56% respectively. The percentage yields of alkaloids in O. basilicum and O. gratissimum were not significantly different (P>0.05). There were significant differences (P<0.05) in malondialdehyde (MDA) concentration due to the herbs used and the length of days of storage of the meat. Generally, MDA concentrations in the meat increased (P<0.05) with increasing storage length in all meat samples irrespective of the herb used. The herbs screened for phytochemical constituents had the potential to improve the oxidative stability of chevon. A combine usage of these herbs as a formulated seasoning was of more benefit than single (uncombined) usage. However, this is a basic research and the result should not be applied directly in food preparation as the phytochemicals in the herbs could be dangerous at high concentration.