The Chemical Composition, Fermentation End-Product of Silage, and Aerobic Stability of Cassava Pulp Fermented with Lactobacillus casei TH14 and Additives

Simple Summary Ruminant feed is one potential application for cassava pulp (CSP), an industrial waste product generated during the manufacturing of cassava flour. However, because of its high fiber content and low protein content, the quality should be enhanced. We observed that fermenting CSP with urea, molasses, and Lactobacillus casei TH14 improves silage quality, which might be utilized as an alternative feed source for ruminants. This study evaluated the effects of cassava pulp fermented with Lactobacillus casei TH14, urea, and molasses on its chemical composition, the fermentation end-product of silage, and aerobic stability. A 2 x 2 x 2 factorial arrangement with a randomized complete block design was employed. The first factor: level of L. casei TH14 [L; 0 and 10(5) cfu/kg fresh matter (FM)], the second factor: level of molasses (M; 0 and 4% DM), the third factor: level of urea (U; 0 and 4% DM), and the number of days of fermentation (7, 14, and 21 days) were evaluated using a statistical block. There were interactions among CSP fermented with different additives on DM content (p < 0.05). The control group (CON) and CSP fermented with L, LxM, and LxU had lower DM contents than U, UxM, and LxUxM. The crude protein of CSP was increased by interaction of LxU and UxM additives (p < 0.05 and p < 0.01, respectively). Interaction effects between L and U and NDF content were detected (p < 0.05). The LxU combination resulted in a significantly lower NDF than the other groups. The interaction between LxUxM had no effect on the change in the CSP fermentation process (p > 0.05). The combination of UxM caused a poorer pH than other groups (p < 0.01). The ammonia-N content was higher than others, when CSP was fermented with LxU (p < 0.01) or UxM (p < 0.05), respectively. The lactic acid levels in fermented CSP were higher (p < 0.01) than in other groups through the L. casei. The interaction between LxUxM had an influence on lactic acid bacteria (LAB) (p < 0.01) and aerobic bacteria (p < 0.01). The highest LAB population (p < 0.01) at 10(6) cfu/g FM was found in CSP fermented with L. casei and molasses. In conclusion, the current study shows that CSP treated with LxUxM resulted in good preservation by recovering DM, a low number of aerobic bacteria, and greater LAB than other treatments, with the exception of the LxUxM addition. A 21-day fermentation period is advised because it produces products with greater levels of crude protein, lactic acid, acetic acid, and propionic acid.

Automated summary

Ruminant feed application of cassava pulp (CSP) can be enhanced by fermenting it with urea, molasses, and Lactobacillus casei TH14. This study evaluated the effects of these additives on the chemical composition, fermentation end-product, and aerobic stability of CSP. The results showed that the combination of LxUxM resulted in good preservation of CSP with improved crude protein and lactic acid levels. A 21-day fermentation period was recommended for better quality products.