Citric acid, an essential organic acid, shows exceptional versatility and has widespread application in everyday life, including not only the food and beverage industry but also the pharmaceutical and agricultural sectors. The diverse role of citric acid, such as its ability to enhance flavor, regulate pH levels, and act as an antioxidant, has led to a significant growth in its production demand, hence highlighting its substantial economic significance. Extensive and advanced research is conducted to address the diverse requirements of people, with the aim of improving productivity in a manner that is both cost-effective and environmentally sustainable. This thesis offers an in-depth analysis of the scientific literature underlying Aspergillus niger and its role in citric acid production. Additionally, it explores the various factors that influence the fermentation process and the challenges associated with scaling up production. The objective of this study is to analyze and compare the outcomes of two separate experiments conducted on fermentors with different parameters. The aim is to determine which experiment yields a higher quantity of product given a specific amount of glucose and, at last, investigate the root causes for this difference.