The Physical And Microbiological Investigation Of Some Local Beverage Drinks
[A CASE STUDY OF ILORIN METROPOLIS, KWARA STATE]

3.3 Physicochemical characteristics of the local drinks
3.3.1   Determination of pH of the local drinks
10 ml of each drink was transferred to sterile bottle, with the aid of digital pH meter and using known pH solution as positive control and water as negative control their pH were determined and recorded.
3.3.2 Macroscopic Examination of Local Drinks
The colour and viscosity of the samples were determined macroscopically and recorded for each sample.
3.3.3   Sterilization of Materials
All materials used in this study were purchased newly and their sterility were tested by incubating them with sterile infusion fluid and their sterility ware ascertained after 24hoursby showing no growth.
3.3.4 Plating Techniques (pour plating):
         Materials
1.    Sterile universal bottles samples
2.    Samples (Pito, Zobo, Kunu and Soy milk drink )
3.    Nutrient, Blood and MacConkey agar
4.    Sterile Petri-dishes
5.    Bunsen burner (Flame)
6.    Colony counter with magnifying glass
7.    Sterile capped test tubes
8.    Pipette of various sizes( e.g. 10, 0.1, 1.0, and 2.0µl)
3.4   SAMPLE PREPARATION
 Serial Dilution of Samples:
Three tubes ware labelled for Kunu (K1, K2, K3), Zobo (S1, S2, S3), Pito (P1, P2, P3) and Soy milk (SY1, SY2, SY3) and 9mls of normal saline were dispensed into each tubes.
Kunu tubes: 1ml of Kunu purchased from market was added to tube K1 of Kunu containing 9ml of normal saline making (1:10 dilution) and was mixed. From tube K1, 1ml was taken and added to tube K2 containing 9ml of normal saline making (1:20 dilution). From tube K2, 1ml was taken and added to tube K3 containing 9ml of normal saline making (1:30 dilution). From tube K3, 1ml was taken and added to tube K4 containing 9ml of normal saline making (1:40 dilution). From tube K4, 1ml was taken and added to tube K5 containing 9ml of normal saline making (1:50 dilution). Similarly, Zobo, Pito and Soy milk were diluted serially as done for Kunu.
Serially diluted samples (Kunu, Zobo, Pito and Soy milk) were poured into already labelled (K1, K2, K3,  S1, S2, S3,  P1, P2, P3, , SY1, SY2, and SY3,  respectively) into sterile petri dish and cooling blood and MacConkey agar were added and the dishes were gently rotated to mix the culture and the medium thoroughly. The medium covered the plate evenly. The agars were allowed to completely gel without disturbance. The plates ware incubated aerobically at 350C for 18 to 24 hours.