## 3 Results and Discussion
### Moisture Content, Temperature, and pH Variation during a 30-Day Computing Period  
A compost pile with the optimal initial moisture content and mature compost seeding amount identified in Section 3.1 was used to study the moisture content, temperature, and pH variation during the entire composting process. The physicochemical properties of the compost mixture are presented in Table 1.  
Figure 2 shows the moisture content variation during the composting period. The initial moisture content was 65%, which was within the optimal range of 55-70% for the food waste reported in this study. At this optimal range, the pile was not too dry or too wet for the microbial communities to thrive. For instance, sawdust was added initially to reduce the high moisture content of the food waste, and water was added during the thermophilic stage, where water loss occurs via evaporation. The moisture content was maintained at 45-65% throughout the entire process, as shown in Figure 2; hence, the microbial community in the pile had the conditions necessary for an effective performance [21]. Figure 1: Temperature development influenced by (**a**) initial moisture content and (**b**) seeding proportions. The temperature variation is presented in Figure 3. The temperature sharply rose from an ambient temperature to 50 \({}^{\circ}\)C after one day, then it briefly stayed steady until about day 4. This abrupt increase in temperature is an indication of the increasing microbial activity when utilizing the compost material [28]. This phase is usually characterized by an abundance of mesophilic microorganisms [33]. However, as the temperature rose to 50 \({}^{\circ}\)C, the conditions became unfavorable for the mesophiles, while the thermophiles within the microbial community started to thrive [34]. This group of microbes would first need to acclimize before growing. This was probably the reason for the observed plateauing in the temperature, as shown in Figure 3. Thereafter, the temperature steadily rose to 70 \({}^{\circ}\)C at day 7 and stayed relatively constant at 70-75 \({}^{\circ}\)C until day 20. During this thermophilic phase, the microbial activity is at its highest. However, as the nutrients diminish, the microbial activity decreases, leading to the cooling phase, where temperatures fall (days 20-25) and tend to approach the ambient temperature. The compost is said to mature when the temperature of the pile corresponds with the surrounding temperature. \begin{table}
\begin{tabular}{l c c c c} \hline
**Component** & **Weight (kg)** & **pH** & **C/N Ratio** & **Moisture Content (\%)** \\ \hline
1. Food waste (comprised of 80 kg & & & & \\ vegetable and fruit peel, 70 kg & 260 & 4.3 & 11 & 80 \\ meat and animal skin and 110 kg & & & & \\ cooked food & & & & \\
2. Sawdust & 60 & 6.8 & 519 & 15 \\
3. Mature compost & 80 & 6.5 & 29 & 20 \\ \hline
**Initial compost mixture** & **400** & **4.5** & **22** & **65** \\ \hline \end{tabular}
\end{table} 
Table 1: Physicochemical characteristics of the 400 kg compost pile. Figure 2: Moisture content variation during the composting period. Figure 4 shows the pH variation during the composting period. The initial composting mixture was acidic at a pH of 4.5 and the acidity further increased to 3.6 after day 1. This observation is similar to other previous studies [35; 36]. The acidity is probably due to the organic acids, such as acetic acid, that are naturally produced during the fermentation of the food waste [35; 37]. However, the pH of the compost pile rises with the increasing composting period. This could be because of the vaporization of the organic acid due to the rising temperature of the pile and the turning of the pile for aeration. Most of the organic acids produced during the fermentation are volatile and the increase in compost temperature would allow them to escape into the environment as gases. NH\({}_{3}\), a byproduct of the microbial utilization of the available nitrogen sources, will also be generated during the composting period [8].