Nutritional, Phytochemical and Sensory Properties of Herbal Tea: Cymbopogon citratus, Moringa oleifera and Zingiber officinale
Theophilus M. Ikegwu *
Department of Food Science and Technology, Faculty of Agriculture, Nnamdi Azikiwe University, Awka, Nigeria.
Chika U. Obiora
Department of Food Science and Technology, Faculty of Agriculture, Nnamdi Azikiwe University, Awka, Nigeria.
Jennifer N. Onwuemeri
Department of Food Science and Technology, Faculty of Agriculture, Nnamdi Azikiwe University, Awka, Nigeria.
Nkemakonam N. Anene
Department of Food Science and Technology, Faculty of Agriculture, Nnamdi Azikiwe University, Awka, Nigeria.
Paige N. Igwe
Department of Food Science and Technology, Faculty of Agriculture, Nnamdi Azikiwe University, Awka, Nigeria.
Chioke A. Okolo
Department of Food Science and Technology, Faculty of Agriculture, Nnamdi Azikiwe University, Awka, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
The research investigated the effect of drying temperature and time; and the proportion of different samples on the physicochemical and sensory properties of herbal tea from lemongrass, moringa leaf and ginger. The samples were analyzed using standard methods. The results obtained showed that there were significant (P<0.05) differences in the proximate composition (%) of the samples (with fats, protein, carbohydrate, ash, moisture, and fibre contents ranged from 0.01-4.01, 3.90-6.67, 67.59-78.91, 2.02-6.90, 3.14-6.01 and 8.89-12.02, respectively. The phytochemical analyses showed significant (P<0.05) variations that could be attributed to the effect of temperature of drying, duration and proportion of ginger, moringa and lemon grass leaves. The oxalates ranged from 0.01-3.89 mg/g, alkaloids (2.89-7.89 mg/g), saponin (0.22-5.47 mg/g), phytates (0.08-6.67 mg/g), phenols (0.01-4.01 mg/g, flavonoids (0.06-16.34 mg/g, steroids (0.33-7.83 mg/g and Terpenoids (0.02-7.98 mg/g). It was observed that the vitamins (mg/g) and minerals (mg/g) likewise showed significant (P<0.05) variations with vtamins A, B1, C and D ranging from 7.57-12.05, 1.78-11.45, 2.77-11.91 and 4.32-12.11, respectively while the magnesium, calcium, manganese, potassium and sodium ranged from 3.64-8.89, 2.36-8.20, 0.00-0.04, 3.22-12.33 and 6.13-10.12, respectively. The samples with higher content of the lemon grass were observed to contain more flavonoids than others but increased concentration of the moringa and reduced the flavonoids content.
Keywords: Drying, phytochemical, herbal tea, thermal properties, antioxidant properties