Effect of Fermentation Time on the Physical Quality of Sweet Potato Leaf Silage (Ipomoea batatas L.) Fermented Using Rumen Liquid Starter

Abstract

Silage is one of the most widely used forage preservation methods for maintaining the availability of quality feed throughout the year. Sweet potato leaves (Ipomoea batatas L.) have considerable potential as a raw material for silage due to their abundant availability and relatively good nutritional content. This study aimed to determine the effect of fermentation duration using rumen fluid as a starter on the physical quality of sweet potato leaf silage. The study was conducted using a completely randomized design (CRD) with four fermentation duration treatments, namely 0, 7, 14, and 21 days, with four replications for each treatment. The physical quality parameters observed included pH, color, aroma, texture, and mold growth. The results showed that fermentation for 7 to 14 days produced an optimal pH ranging from 3.63 to 4.13, indicating that the lactic acid fermentation process proceeded effectively. During this period, the silage retained its natural green color, exhibited a characteristic sour fermentation aroma, and had a soft, non-slimy texture. In contrast, fermentation for 21 days resulted in a decline in physical quality, as indicated by an increase in pH to 5.75, a change in color to dark brown, the development of a putrid and sour odor, an excessively mushy texture, and uncontrolled mold growth. These conditions indicate the occurrence of secondary fermentation that negatively affected silage quality. Based on these findings, the optimal fermentation duration for sweet potato leaf silage using rumen fluid as a starter was 7 to 14 days, as this duration produced silage with good physical characteristics, an optimal pH, and controlled mold growth.