ADL determination: acid-insoluble lignin

The determination of ADL (Acid Detergent Lignin) allows for the measurement of the insoluble lignin fraction after acid treatment. This analysis complements the determination of ADF (Acid Detergent Fiber) and is part of the Van Soest system , widely used to characterize the fiber composition of plant raw materials and animal feed. Lignin, a structural component of plant cell walls, directly influences the digestibility and energy value of forages.

This method is essential for assessing the quality of fiber-rich foods, optimizing formulations for animal nutrition, and ensuring the consistency of plant-based raw materials.

Principle and operation of the method

The method for determining acid-insoluble lignin (ADL) is based on the standards DIN EN ISO 13906:2008-11 and ISO 16472:2006-04 Van Soest method .
The sample is first treated with an acidic detergent solution that removes cellulose and hemicellulose, leaving only insoluble lignin. This fraction is then isolated, dried, and weighed to determine the acid-insoluble lignin content.

This analysis thus makes it possible to distinguish the main fibrous fractions:

• NDF (Neutral Detergent Fiber): cellulose, hemicellulose, lignin.
• ADF (Acid Detergent Fiber): cellulose + lignin.
• ADL: lignin alone, insoluble in acid.

Comparing these values ​​allows us to calculate the potential digestibility and nutritional quality of forage or animal feed.

Analytical performance and related analyses

ADL analysis is a reference method for evaluating plant fibers. It offers high precision and excellent reproducibility for both agricultural and animal matrices. This analysis is generally combined with other tests from the same system to obtain a complete characterization.

• NDF (Neutral Detergent Fiber) dosage ,
• ADF (Acid Detergent Fiber) dosage
• the dosage of cellulose and hemicellulose ,
• or the dosage of raw ash and organic matter .

All of these analyses provide a complete view of the cell wall composition and digestibility of feed intended for ruminants, horses or other herbivorous species.

Applications and areas of use

ADL assays are used primarily in the animal nutrition and agronomic research :

• Forage evaluation : estimation of the digestibility and nutritional quality of silage, hay and fibrous mixtures.
• Animal feed formulation : optimization of digestible and indigestible fiber intake in rations.
• Analysis of plant extracts : characterization of lignin content for plants used as raw material.
• Quality control and traceability : comparison of batches of raw materials to ensure nutritional consistency.

These analyses help to improve livestock performance, adjust formulations and meet the requirements of specifications in animal nutrition.

The advantages of the YesWeLab service

YesWeLab collaborates with a network of partner laboratories specializing in plant fiber analysis and animal nutrition, accredited to ISO 17025 and COFRAC standards. Each project is entrusted to a laboratory expert in the Van Soest system to guarantee the reliability and comparability of the results.

Thanks to its digital analysis platform, YesWeLab simplifies analysis management: quote requests, online tracking, and results delivery. Since 2020, numerous players in the agri-food, animal nutrition, and agronomic research sectors have trusted YesWeLab for their fiber and lignin analyses.

For any specific request regarding ADL assay, contact our scientific team to obtain a personalized quote and support tailored to your analytical needs.