Determination of volatile fatty acids

What are volatile fatty acids?

Volatile fatty acids (VFAs) are short-chain organic acids generated during fermentation processes or the degradation of organic matter. The most commonly analyzed are:

• Acetic acid
• Propionic acid
• Butyric acid
• Sometimes: isobutyric, isovaleric, caproic, etc.

These compounds are key indicators of the fermentation quality and biodegradation status of a sample. Their quantification makes it possible to monitor the evolution of biological processes, optimize formulations or control natural or industrial fermentations.

Why dose AGVs?

The dosage of AGVs is essential in many areas:

• Assessment of the quality of silage for animal nutrition (cattle, sheep, goats)
• Control of fermentation in food, plant or nutraceutical products
• Monitoring of methanization or composting processes
• Analysis of the stability or contamination of plant extracts or organic products
• Monitoring of sludge, effluent or digestate in an environmental framework
• Optimization of fermentable formulations or probiotics

An unbalanced VFA profile may indicate uncontrolled fermentation, microbial contamination, or loss of nutritional value.

Analytical method used

Volatile fatty acid analysis is generally performed by:

• Gas chromatography with flame ionization detection (GC-FID)

This method is recognized for its reliability, sensitivity, and ability to accurately separate VFAs, even in complex matrices. It allows for accurate quantification at trace levels and good reproducibility, essential in regulated or industrial environments.

Affected matrices

The most commonly analyzed matrices for AGVs include:

• Corn, grass, and alfalfa silage
• Fermented products: drinks, plant extracts, kombucha, etc.
• Sludge, digestate, compost from the treatment of organic waste
• Wastewater or agricultural effluent
• Animal nutrition formulations or premixes
• Probiotic or fermentable supplements

The analysis can be adapted to solid, liquid or semi-solid matrices after extraction and specific treatment.

Regulatory context and quality

Although AGVs are not systematically subject to regulatory thresholds, their dosage is often required in:

• Internal quality controls of animal feed manufacturers
• Agronomic or environmental compliance audits
• Industrial fermentation optimization programs
• R&D approaches on products rich in microbiota or ferments
• HACCP or FAMI-QS assessments

Their dosage also makes it possible to establish analytical traceability within the framework of certifications or supplier contracts.

Why go through YesWeLab?

At YesWeLab , we provide you with a network of partner laboratories specializing in physicochemical and microbiological analyses, rigorously selected and ISO 17025 certified or COFRAC accredited.

Our services include:

• Selecting the laboratory best suited to your matrix
• Personalized technical support based on your industrial constraints
• Access to a secure digital platform to manage your analyses, results and history
• Dedicated scientific expertise to support you in interpreting fermentation profiles

Need to measure volatile fatty acids in your samples?

YesWeLab helps you master your fermentation processes, organic formulations, and quality control processes.
Contact our scientific team now for a personalized study or a quick quote.