Mettler dl12 titrator

Volatile fatty acids (VFA), lactic acid, ethanol, and pH were analyzed at Cumberland Valley Analytical Services. Briefly, each fermented silage sample was mixed, and a 25 g wet sample was taken and diluted with 200 mL deionized water. After overnight incubation under refrigeration, the sample mixture was blended for two minutes and filtered through coarse (20–25 μm particle retention) filter paper. For volatile fatty acid (VFA) quantification, 3 mL of the extract was filtered through a 0.2 μm filter membrane and a 1.0 μL subsample was injected into a Perkin Elmer AutoSystem Gas Chromatograph (Perkin Elmer, Waltham, MA, USA) equipped with a Restek column packed with Stabilwax-DA (Restek, Bellefonte, PA, USA). For lactic acid quantification, a 1:1 ratio of extract to deionized water was placed in a YSI 2700 Select Biochemistry Analyzer (YSI, Yellow Springs, OH, USA) to determine l-lactic acid. The pH was read prior to analysis of the titratable acidity from 30 mL of the previous extract by a Mettler DL12 Titrator (Mettler-Toledo, Columbus, OH, USA) using 0.1 N NaOH, pH 6.5.

The nutritional characteristics (ADF, NDF, starch, crude protein, soluble protein, and ethanol soluble carbohydrates) of samples of fresh forage were analyzed at Cumberland Valley Analytical Services (Waynesboro, PA, USA) using wet chemistry methods (https://www.foragelab.com/Resources/Lab‐Procedures). Volatile fatty acids (VFA), lactic acid, ethanol, and pH were also analyzed at Cumberland Valley Analytical Services. Briefly, each fermented silage sample was mixed, and a 25 g wet sample was taken and diluted with 200 ml deionized water. After incubation for 2 h in the refrigerator, the sample mixture was then blended for 2 min and filtered through a coarse (20–25 µm particle retention) filter paper. For VFA quantification and ethanol, 3 ml of extract was filtered through a 0.2 µm filter membrane, and a 1.0 µl subsample was injected into a Perkin Elmer AutoSystem gas chromatograph (Model 710, Perkin Elmer, USA) equipped with a Restek column packed with Stabilwax‐DA (Restek, USA). For lactic acid quantification, a 1:1 ratio of extract to deionized water was placed in a YSI 2700 Select Biochemistry Analyzer to determine lactic acid. pH was measured with a Mettler DL12 Titrator (Mettler‐Toledo, USA) using 0.1 N NaOH to a pH of 6.5.