This study aims to produce the best fermented product from a mixture of palm kernel cake (PKC) and cassava byproduct (CB) by optimizing the addition of minerals and fermentation duration. The fermentation experiment was designed using a Completely Randomized Design with a 4x6 factorial pattern with three replications for each treatment combination. The first factor was the level of mineral addition (M0 = no mineral addition, M1 = mineral addition with the composition: 2.5 g KCl, 12.5 g ZA, 7.5 g urea, and 2.5 g NPK, M2 = mineral addition with the composition: 5 g KCl, 25 g ZA, 15 g urea, and 5 g NPK, and M3 = mineral addition with the composition: 7.5 g KCl, 37.5 g ZA, 22.5 g urea, and 7.5 g NPK), the second factor was fermentation duration (D0 = 0, D1 = 24, D2 = 48, D3 = 72, D4 = 96, and D5 = 120 hours). The results showed that the best combination for producing the fermented product was the mineral addition level M2 with the composition: 5 g KCl, 25 g ZA, 15 g urea, and 5 g NPK, and the fermentation duration D2 (48 hours). This combination resulted in a product with a high crude protein content of 23.56%, low crude fiber content of 8.83%, low crude fat content of 3.6%, and a fairly high metabolizable energy content of 3,029.33 kcal. The fermented products from this research are expected to be used as non-conventional alternative feedstuff to be tested as feedstuff for various types of poultry.
Keywords | Mineral addition level, Fermentation duration, Palm kernel cake, Cassava byproduct, Aspergillus niger, Nutrient value