## 2 Materials and Methods
### Preparation of Fermented Millet--Ginger \"Ibyer\" Beverage Blends
#### 2.5.3 Proximate Analysis  
Determination of Moisture  
The moisture of samples was determined as described by the AOAC method [33]. Empty crucibles were washed, dried in an oven at 100 \({}^{\circ}\)C for \(\sim\)1 h, and measured as (\(W_{1}\)). A sample of \(\sim\)2 g was measured into the crucible (\(W_{2}\)) and dried at 70 \({}^{\circ}\)C to a constant weight obtained as (\(W_{3}\)) [33], and moisture content was calculated from Equation (1) below:  
\[Moisturecontent(\%)\ =\ \frac{W_{2}\ -\ W_{3}}{W_{2}\ -\ W_{1}}\ \times\ 100 \tag{1}\]  
Hence, \(W_{1}\) = weight of empty crucible  
\(W_{2}\) = weight of crucible + sample before drying  
\(W_{3}\) = weight of crucible + sample after drying  
Determination of Ash  
The ash of samples were determined as described by the AOAC method [33] with slight modifications. A crucible was preheated and cooled in a desiccator, thereafter weighed as (\(W_{1}\)). Approximately 2 g sample was added into the crucible and its content weighed as (\(W_{2}\)). A crucible with its content was then heated in a muffle furnace up to 550 \({}^{\circ}\)C for \(\sim\)7 h. The crucible temperature was reduced in a desiccator and measured again after reaching room temperature, and weighed as (\(W_{3}\)) [33]. The ash content was as calculated from Equation (2) below:\[ \begin{split} Ashcontent(\%)\ =\ \frac{W_{2}\ -\ W_{3}}{W_{2}\ -\ W_{1}}\ \times\ 100 \end{split}  \tag{2}\]  
Hence: \(W_{1}\) = Weight of empty crucible  
\(W_{2}\) = Weight of crucible + weight of sample before ashing  
\(W_{3}\) = Weight of crucible + weight of sample after ashing  
Determination of Crude Fat  
The crude fat of samples was determined based on the Soxhlet extraction method as described by the AOAC method [33] with slight modifications. Approximately 2 g of sample was measured into a labeled extraction thimble and placed in an extraction flask. Approximately 300 mL of diethyl ether was added to the flask. The extraction thimble was sealed and (extraction) carried out for \(\sim\)6 h. At the end of extraction, the diethyl ether was removed by evaporation and dried at 70 \({}^{\circ}\)C for an hour in the oven, and the temperature was reduced in desiccators before it was measured, following the method of AOAC [33], as calculated from Equation (3) below:  
\[ \begin{split} Fatcontent(\%)\ =\ \frac{Weightffat}{Weightfsample}\ \times\ 100 \end{split}  \tag{3}\]  
Determination of Crude Fiber  
The crude fiber of samples was determined as described by the AOAC method [33], with slight modifications. Approximately 2 g of defatted samples with diethyl ether, 0.255 M sulphuric acid (200 mL H2 SO4) and dilute sodium hydroxide (200 mL NaOH) were added. The mixture was heated to boiling point and the insoluble material was transferred to a filter paper through a Buchner funnel connected to a vacuum pump. The filtrate was heated at 130 \({}^{\circ}\)C for \(\sim\)2 h, cooled in a desiccator, and measured. Filtrates were transferred to a muffle furnace and ashed at 550 \({}^{\circ}\)C for \(\sim\)30 min, cooled, and weighed. The percentage of crude fiber content was thus calculated:  
\[ \begin{split}\%\ \text{Crude fiber}\ =\ \text{the loss in weight after incineration}\ \times\ 100 \end{split}  \tag{4}\]  
Determination of Crude Protein  
The crude protein was determined as described by the AOAC method [33], with slight modifications. Approximately 2 g sample was measured into a Kjeldahl digestion flask, followed by the addition of 0.1 g potassium sulphate with 1.0 mL copper sulphate solution. Approximately 25 mL concentrated sulphuric acid was added with few boiling catalysts. The flasks were heated in a fume chamber to a clear solution. The solution was cooled to room temperature for \(\sim\)25 min. The solution was transferred into a 250 mL volumetric flask, made up to the level with distilled water. Approximately 5 mL digest in a measuring cylinder was pipetted into the apparatus, diluted by adding 5 mL of 50% NaOH aqueous.