Liquid Smoke as Fat Protector and Its Effect on Rumen Fermentation Characteristics and Microbial Activity

This study was conducted to determine the effect of liquid smoke as a fat protector on unsaturated fatty acids (UFAs) and its effect on rumen fermentation characteristics and microbial activity. Crude palm oil (CPO) was mixed with Prosteo skim milk (1:2), then divided into three treatments i.e., crude palm oil without protection by liquid smoke as a control (P0), crude palm oil protected by 2.5 of liquid smoke (P1), and crude falm oil protected by 5.0 of liquid smoke (P2). For in vitro testing, 300 mg of the feed substrate (elephant grass and bran with the ratio of 60:40) was added with 5 of each crude palm oil preparation of P0, P1, and P2 and put in a fermentor syringe. Then, 30 mL of the mixture of rumen fluid and buffer-minerals solution (1:2) was added into each syringe fermentor and flushed with CO2. The fermentor syringes were incubated in a water bath at 39ᵒC for 48 hours. Variables measured were fatty acid composition, fermentation characteristics, and rumen microbial activity. The data were analyzed by the analysis of variance with a completely randomized design. The results showed that the protection of CPO with liquid smoke in P1 and P2 groups decreased saturated fatty acids (SFAs), but increased (p<0.01) monounsaturated fatty acids (MUFAs), polyunsaturated fatty acids (PUFAs), and CMCase activity. Protection of CPO with 2.5 of liquid smoke (P1) significantly increased (p<0.01) fermentation characteristics (NH3 content and pH). It can be concluded that the use of 2.5 of liquid smoke has a better effect on feed fats protection, because it can reduce hydrogenation, increase UFAs, and has no negative effects on fermentation characteristics and microbial activity. © 2021