Why is Accurate Fiber Determination Essential?
Fiber matters for both animal feed and human food, supporting overall health. Measuring the amount and type of fiber accurately is essential. Fiber determination provides insights across several fields:
- Animal feed production: knowing the fiber content helps formulate diets that improve digestion, gut health and animal performance.
- Food labeling: accurate fiber content supports correct labeling so consumers can make informed choices.
- Nutritional research: understanding how different fiber types affect health guides better dietary recommendations.
All solutions use crucible technology in line with official standards (ISO and AOAC). Fiber residues stay in the crucibles throughout every step, reducing error risk and ensuring consistent results.
Fiber Determination in Feed Stuff
What is the Crude Fiber (Weende) Method?
The crude fiber method estimates fiber or plant cell wall content. It is widely used for fiber determination in monogastric animals. The method involves:
- Solubilization (digestion): dissolving non-cellulosic compounds with sulfuric acid and potassium hydroxide solutions.
- Crude fiber measurement: measuring the loss on ignition of the dried residue left after digestion.
It applies to grains, meals, flours, feeds and fiber-bearing materials from which fat can be extracted.
Acid digestion
- Boiling
- Filtering
Washing
- Washing with water after acid digestion
Alkali digestion
- Boiling
- Filtering
Washing
- Washing with water after alkali digestion
How Does the Detergent Fiber (Van Soest) Method Work?
The Van Soest method is based on the idea that plant cells split into less-digestible cell walls of hemicellulose, cellulose and lignin. This allows fiber to be fractioned into NDF, ADF and ADL, used to estimate energy intake from feed — especially for ruminants.
Neutral Detergent Fiber, NDF
The sample is digested in Neutral Detergent Solution (NDS) with a heat-stable amylase enzyme, separating the neutral-detergent-soluble fraction (sugars, starches, soluble pectin — filtered out) from the insoluble fraction (cell wall substances: hemicellulose, cellulose, lignin).
The remaining dry matter is measured; its proportion gives the neutral detergent fiber (NDF).
Acid Detergent Fiber, ADF
Acid Detergent Solution (ADS) dissolves the hemicellulose while lignin and cellulose stay insoluble. The residue — cellulose and lignin — is weighed to determine ADF.
Acid Detergent Lignin, ADL
The residue from the ADF analysis is dissolved in 72% sulfuric acid, leaving lignin (ADL), which is measured gravimetrically.
Fiber Determination Analyzers and Extractors for Feed Analysis
FIWE Advance Automatic Fiber Analyzer
A fully automatic analyzer for crude and detergent fiber determination using official reference methods. It minimizes operator time and offers a clear user interface and cloud connectivity.
Learn more
FIWE Fiber Analyzer
Fiber analyzers using pre-heated reagents for fiber analysis according to Weende, Van Soest and other official methods.
Learn more about FIWE 6
COEX Cold Extractor
Cold extractor for rapid fat extraction on feed samples, directly in FIWE Advance and FIWE glass crucibles.
Learn moreDietary Fiber Determination
Dietary fiber is the part of plant-based food that the human small intestine does not digest. It is a key nutrient: it promotes satiety, regulates intestinal function and modulates nutrient absorption.
Thanks to these benefits, fiber is increasingly used in functional foods, and manufacturers declare its content on packaging as part of nutritional labeling.
The procedure involves a series of digestions with thermostable enzymes using the GDE enzymatic digester, in line with the official AOAC method for total dietary fiber.
The procedure takes time, and following every step is essential for precise results.
The following is a simplified version of the full process.
1. Sample Preparation
2. Enzymatic Digestion
3. Filtration
4. Protein Determination
5. Ash Determination
Enzymatic Digester and Filtration Unit for Dietary Fiber Determination
Our products
Fat extraction for fiber determination
The COEX is used to perform preliminary defatting of the sample prior to fiber determination with FIWE and FIWE Advance. The COEX guarantee maximum reliability and is a mandatory step for all feed sample with high fat content.
The efficient pump aspirates and removes the fatty component that will be collected in a dedicated waste tank/bottle.
The COEX is easy to use and convenient, all the reagents can be added through the same channel.
Avoid sample loss and transfers
The COEX ensures rapid fat extraction directly into the same glass crucibles used by the FIWE and FIWE Advance whenever the fat content of feed sample is high and need to be reduce to less than 1%.
The crucible containing the defatted sample is transferred directly to the FIWE and FIWE Advance analyzer eliminating possible errors due to sample transfer.
Rapid and efficient filtration
CSF6 is optimal for efficient filtration, after the samples have been processed by the Enzymatic Digester GDE.
This VELP combination allows the analysis to be carried out in accordance with the official AOAC (Determination of Total Dietary Fibre) method with a drastic reduction in the time required compared to the manual procedure.
CFS6 filtration unit is able to perform single or multiple samples at the same time, up to a maximum of 6 samples at the same time, in less than 20 minutes, even at full load.
Reliable filtration unit
The high efficient pump allows to speed-up the filtration step and the final washing.
Compressed air can be also injected from the bottom to remove any sample accumulated in the filter of the crucible, which affects the quality of filtration.
Crude Fiber, Neutral & Acid Detergent Fiber
FIWE 3 (like the FIWE 6) is a fiber analyzer suitable for raw fiber extraction, conventionally known as an indigestible residue. Rapid analysis, reliable results and high reproducibility are some of the most relevant benefits of these units which are ideal for the following applications:
- the Weende method, the oldest analytical procedure still in use today, in which fiber concentration is measured as crude fiber (CF)
- the Neutral Detergent Fiber (NDF), a method developed by Van Soest, now the most common measure of fiber used for animal feed analysis
- Acid Detergent Fiber (ADF), a portion of the plant fiber and includes cellulose, lignin and variable amounts of xylans.
- Acid Detergent Lignin (ADL) determination and Wijkstrom technique, a modification of the Weende method
High Reliability, Single or Multiple Extractions
Perform single or multiple extractions including boiling, rinsing and filtration steps with the maximum reproducibility available.
No sample transfer prevents any possible sample loss, as crucibles can also be used as sample vessels during weighing, drying and washing.
Pre-heat the reagents with RC2 hot plate (included), and pour them directly into the system.
No transfer and sample loss
In order to prepare the sample for fiber analysis, COEX ensures rapid fat extraction directly into the same glass crucibles used by the FIWE series.
The crucible, containing the defatted sample, is transferred directly to the FIWE analyzer, eliminating.
Crude Fiber, Neutral & Acid Detergent Fiber
FIWE 3 and FIWE 6 are fiber analyzers suitable for raw fiber extraction, conventionally known as an indigestible residue. Rapid analysis, reliable results and high reproducibility are some of the most relevant benefits of these units which are ideal for the following applications:
- the Weende method, the oldest analytical procedure still in use today, in which fiber concentration is measured as crude fiber (CF)
- the Neutral Detergent Fiber (NDF), a method developed by Van Soest, now the most common measure of fiber used for animal feed analysis
- Acid Detergent Fiber (ADF), a portion of the plant fiber and includes cellulose, lignin and variable amounts of xylans.
- Acid Detergent Lignin (ADL) determination and Wijkstrom technique, a modification of the Weende method
High Reliability, Single or Multiple Extractions
Perform single or multiple extractions including boiling, rinsing and filtration steps with the maximum reproducibility available.
No sample transfer prevents any possible sample loss, as crucibles can also be used as sample vessels during weighing, drying and washing.
Pre-heat the reagents with RC2 hot plate (included), and pour them directly into the system.
No transfer and sample loss
In order to prepare the sample for fiber analysis, COEX ensures rapid fat extraction directly into the same glass crucibles used by the FIWE series.
The crucible, containing the defatted sample, is transferred directly to the FIWE analyzer, eliminating.
Fully Automatic Crude and Detergent Fiber
Accurate and reproducible results are what a scientist of the animal feed industry needs for fiber determinations to meet the requirements of product labeling and quality control.
The FIWE Advance automates digestion, washing and filtration steps guaranteeing consistency for Crude Fiber with Weende Method and Detergent Fiber for fiber fraction with Van Soest Method NDF, ADF and ADL.
Compliance and consistency
FIWE Advance produces accurate results that always comply with official ISO and AOAC methods for both Crude Fiber and Detergent Fiber.
In addition, the FIWE Advance method using crucibles avoids the loss of fibre due to the transfer of the sample which remains in the crucible for the duration of the analytical procedure.
The sample in fact remains inside the crucibles during the extraction, digestion, washing and filtration phases, and also during weighing and finally for drying and ashing eliminating the risks of error.
Load the samples and go
FIWE Advance saves you valuable time by reducing costs and improving your lab's productivity.
FIWE Advance requires only 2 minutes of operator time compared to more than 50 minutes/operator of a semi-automatic solution.
You will no longer need to preheat and pour chemicals into the columns, manage the temperature for proper boiling, or make sure the filtration is successful.
With FIWE Advance all these operations are automatic and thanks to the cloud connection you are always informed with immediate notifications.
Reliable and accurate
The analytical procedure for the determination of dietary fiber involves a series of digestions of the sample by thermostable enzymes using the enzymatic digester GDE, which operates in accordance with the official AOAC method for the determination of total dietary fiber.
The magnetic stirrer of GDE ensures homogeneity thanks to a continuous and constant stirring of the sample while avoiding overheating that could compromise the success of enzymatic digestions.
Intuitive and precise
Set the timer for unattended operation, you can quickly set the operating time and focus on other tasks.
The transparent polycarbonate tank ensures visibility and enhanced resistance up to 105 °C; whilst the use of deionized water eliminates any possible creation of limestone.
Outstanding temperature regulation is possible with GDE: through an intuitive digital display, it is possible to set the desired temperature, with excellent accuracy of only ± 0.2 °C.
