Effect of Nitrogen Source and Concentrations on Nutrient Content of Fermented Palm Kernel Cake

Nitrogen sources and concentration play a crucial role in producing fermented palm kernel cake (PKC) with high nutritional value. Fermented PKC has high nutrient content, making it ideal for animal feed manufacturing. This study aims to investigate how nitrogen source and concentration affect the nutrient content of fermented PKC. This study examines the impact of several nitrogen sources, including decanter cake, spent ground coffee, and urea ranging from 1 % (w/w) to 5 % (w/w). The study demonstrated that spent ground coffee, particularly at a 3% concentration, is the most effective nitrogen source for fermentation of PKC compared to urea and decanter cake. Spent ground coffee at 3% (w/w) concentration resulted in the highest levels of total protein (24.32 mg/g), lactic acid (1.87 mg/g), and total phenolic content (7.85 mg/g) while maintaining a lower crude fiber content (5%). Additionally, fermented PKC showed significantly higher levels of total protein, phenolic content, lactic acid, and reducing sugar than unfermented PKC, with increases of 98.32%, 99.51%, 77.86%, and 92.75%, respectively. These findings indicate that fermented PKC with a 3% concentration of spent ground coffee could be a nutrient-dense option for animal feed production, underscoring the importance of this study in improving the nutrient content of animal feed.