This application note describes the analysis of organic acids in silage using high-performance liquid chromatography (HPLC). The concentration of lactic acid, acetic acid, and butyric acid in silage can be determined by adding water and filtering the sample. This method is applicable for the analysis of grass, whole plant, and corn silage.
This document describes the analysis of organic acids in silage samples, specifically lactic, acetic, and butyric acid, using High-Performance Liquid Chromatography (HPLC). The procedure utilizes an Agilent Hi-Plex H column to separate volatile and nonvolatile acids without prior derivatization. The note covers the extraction of acids according to EN 13037 and details the chromatographic conditions used for the analysis.
| Column dimensions | 7.7 x 300 mm |
|---|---|
| Mobile phase | 0.005 M H2SO4 |
| Flow rate | 0.7 mL/min |
| Injection volume | 20 µL |
| Temperature | 60°C |
| Detector temperature | 55 °C |
| Pressure | 4.6 MPa |
The concentration of lactic acid, acetic acid, and butyric acid is analyzed.
Add 1.25 L of water to 250 mL of silage and agitate for one hour, then filter through a 0.45 pm membrane.
The system operates at a pressure of 4.6 MPa, which is equivalent to 46 bar or 670 psi.
The column is maintained at 60°C while the detector operates at 55°C.