Fibre Analysis in Food and Feed

Fibre analysis is used to measure the structural components of plant-based materials in food and animal feed. These components influence digestibility, nutrient availability, and overall product quality.
In both food and feed testing, fibre is not a single measurement. It consists of several fractions that describe different parts of the plant cell wall. Understanding these fractions allows laboratories, nutritionists, and producers to better evaluate ingredient performance.
The most commonly tested fibre parameters include:
‣ Crude Fibre
‣ Neutral Detergent Fibre (NDF)
‣ Acid Detergent Fibre (ADF)
‣ Acid Detergent Lignin (ADL)
‣ Acid Detergent Insoluble Nitrogen (ADIN)
‣ Neutral Detergent Insoluble Nitrogen (NDIN)
‣ Total Dietary Fibre (TDF)
Each of these measurements provides different information about fibre composition and nutritional value.

Fibre testing plays a key role in both food and animal feed analysis.
In animal nutrition, fibre affects:
‣ Feed intake
‣ Digestibility
‣ Rumen function
‣ Energy availability
In human nutrition, fibre contributes to:
‣ Digestive health
‣ Blood sugar regulation
‣ Cholesterol control
‣ Satiety
Because of this, accurate fibre analysis is essential for formulation, quality control, and regulatory compliance.

‣ Crude Fibre - A traditional method that estimates the indigestible portion of plant material. It is still widely used but does not capture all fibre components.
‣ Neutral Detergent Fibre (NDF) - Measures total cell wall content, including cellulose, hemicellulose, and lignin. Often used to estimate feed intake potential.
‣ Acid Detergent Fibre (ADF) - Measures the less digestible portion of fibre, mainly cellulose and lignin. Used to assess digestibility and energy value.
‣ Acid Detergent Lignin (ADL) - Measures lignin, the most indigestible fibre component. Often used as an indicator of plant maturity.
‣ ADIN and NDIN - Measure nitrogen bound to fibre. These values help estimate protein availability and detect heat damage in feed.
‣ Total Dietary Fibre (TDF) - Measures both soluble and insoluble fibre. Commonly used in food analysis and labelling.

Fibre is mainly made up of plant cell wall components, including cellulose, hemicellulose, and lignin. Different analytical methods separate and measure these components in different ways.
Modern fibre analysis goes beyond crude fibre to provide a more complete understanding of plant structure and digestibility.

Fibre testing is typically performed using standardised laboratory methods designed to isolate specific fibre fractions. These methods ensure consistent and reliable results for both food and feed samples.
Using multiple fibre measurements together provides a more accurate picture of nutritional quality than relying on a single parameter.