ZOBO PRESERVATION USING EXTRACTS OF CLOVES (SYZYGIUM AROMATICUM MYRTACEAE), GINGER (ZINGIBER OFFICINALE) AND GUINEA PEPPER (XYLOPIA AETHIOPICA ANNONACEAE).

ABSTRACT Zobo is a non-alcoholic beverage produced from Roselle calyx leaves of Hibiscus sabdariffa, commonly consumed for its nutrient, medicinal values, cost-effectiveness, readily available, and ease of preparation. In addition, its good taste, aroma, and colour are the other reasons. The problem of preservation of these beverage such as zobo beverage samples is common in many countries. Extracts from different spices such as cloves, ginger and guinea pepper has been documented to have preservatives effect on food products. This project is therefore to investigate the effect of extracts of cloves, ginger and guinea pepper on the quality of zobo beverage under storage conditions. Zobo leaves and the three spices (cloves, ginger and guinea pepper) were purchased from local market at Ogbomoso. The zobo beverage was produced while the extracts from the three spices was produced separately. Extracts in concentrations of 3%, 5%, and 7%v/v was used to treat three batches of zobo beverage separately while the fourth batch which is untreated serves as control. The treated and untreated samples was grouped into 2 batches. A batch was boiled for 15 minutes while the other was pasteurized for 30 minutes at temperatures between 69-70 in a controlled water bath. The samples were analyzed for chemical, physiochemical composition, the bioactive compounds, antioxidant activities, microbial count and sensory evaluation (colour, flavor, taste and overall acceptability). The data obtained was subjected to statistical analysis. The result of the physicochemical range from pH 3.5 to 5.9; brix 1.0 to 2.0; Total Titratable Acidity (TTA) 0.09 to 7.05; Total Soluble Solid (TSS) 0.97 to 8.88 respectively. The antioxidant ranged from DPPH (mg/g) 69 to 94.6; ABTS (g/100g) 25.3 to 97.5 respectively. The bioactive compound ranged from Phenol (mg/kg) 32.4 to 146; Flavonoid (mg/g) 0.08 to 3.68 respectively. The microbial analysis ranged from Total Viable Count (TVC) 1.5 to 180; Colioform count 2.00 to 5.00 respectively. The colour analysis range from L (lightness) 1.74 to 60.8; a (red-green axis) 1.49 to 23.4; b (yellow-blue axis) -1.21 to 72 respectively. The sensory analysis indicate the addition of spices to zobo, particularly 5 % guinea pepper, affected the sensory attributes in varying degrees, in which 7% ginger treated sample generally scoring higher in taste and acceptability. In conclusion, the study showed the extract of the three spices (clove, ginger and guinea pepper) was able to extend the shelf- life of zobo in which ZGP1 (5% guinea pepper) was preferred by the panelist.