You can extract lactic acid from silage samples using alcohol, which is effective for preparing samples for gas chromatography analysis. This method helps in isolating the lactic acid for accurate measurement.

@Abdelhak Maghchiche

Doesn't alcohol destroy lactic acid?

Thank you for your answer.

Measuring lactic acid in silage using gas chromatography is possible, but the extraction method and sample preparation require careful consideration. Lactic acid must be derivatized to increase its volatility. Without derivatization, lactic acid will not elute properly in gas chromatography.

Extraction with Alcohol. If GC proves too complex, consider HPLC with a UV/RI detector for lactic acid quantification. For silage, enzymatic assays are often faster and more practical.

Recomended

• Use 80% methanol or ethanol (mixed with water) for better extraction efficiency.
• Add 5–10 mL of solvent per gram of silage.
• Homogenize (e.g., vortex, sonicate) and centrifuge to pellet solids.
• Filter the supernatant (e.g., 0.45 µm syringe filter) to remove particulates.

@Yuri Freddy Peña-Rueda

thank you for your help.

yes, because alcohol reacts with lactic acid and allow to hydrolyze, this collect the acid from silage and take the measurement, anyway, understanding the chemistry is crucial

@Mehammed Sied

thank you.