Have you ever been frustrated by discrepancies or non-reproducible results in crude fiber (Crude Fiber), NDF, or ADF analysis, even after following the correct procedures? For animal feed testers, this is a very common and frustrating challenge. The underlying cause often stems from traditional glass filter cups that easily lose fine fiber samples through porous holes or mechanically adhere to the cup walls during vacuum cleaning.

To thoroughly address this issue, upgrading laboratory technology is essential for modern businesses. You can easily find this solution in the list of top modern laboratory equipment necessary for labs. This article will introduce a breakthrough solution using the Sonnen FB25 specialized fiber extraction bag distributed by Duc Duong, which helps to absolutely preserve sample volume and optimize the testing process.

1. Causes of Sample Loss in Traditional Fiber Analysis

1.1 Physical Sample Loss Through Traditional Filter Membranes

In the classic crude fiber analysis process, we often use porous glass filter cups or Gooch funnels to retain the fiber residue after acid and alkali hydrolysis. However, the porous structure of these filter cups is often non-uniform after repeated use and cleaning with strong chemicals. Under the extremely strong suction pressure of the vacuum pump during the filtration step, fine fibers are easily pulled through the pores of the filter membrane.
Furthermore, mechanical adhesion to the glass cup walls is also a serious cause of error. Due to the electrostatic properties and roughness of the abraded glass surface, a significant amount of sample will stick to the cup walls and cannot be completely recovered for drying. According to experimental research published in the Journal of Animal Science (2021), this physical loss can cause negative errors ranging from 1.5% to 3.2% for feed samples rich in fine fiber. This directly degrades the accuracy and repeatability of the test.

1.2 Influence of Feed Sample Grinding Particle Size

The particle size of the analytical sample plays a decisive role in extraction efficiency and sample loss. If the technician grinds the sample too finely (particle size less than 0.5 mm), the fiber particles will easily pass through the filter pores of the Gooch funnel or glass beaker, leading to lower analytical results than the actual value. Conversely, if the particles are ground too coarsely (over 1.0 mm), the acid and alkali solutions will not be able to penetrate deeply enough to thoroughly hydrolyze the non-fiber components, creating a higher false fiber value than the actual value.
To control this risk, international standards such as AOAC 962.09 recommend that the optimal sample grinding size should be between 0.5 mm and 1.0 mm (using a suitable grinding sieve). When the particle size is precisely controlled, using a filter membrane with a uniform pore size smaller than the grinding particle size will be the golden key to completely preventing sample leakage.

The particle size of the ground material should only be between 0.5 and 1 mm to ensure accurate fiber analysis

2. High-Quality Sonnen FB25 Fiber Extraction Bag Solution

2.1 Detailed Specifications of the FB25 Fiber Extraction Bag

To thoroughly overcome the limitations of the Gooch funnel filter method, the Sonnen FB25 fiber extraction bag solution, distributed officially by Duc Duong, has been developed. This filter bag is made from a special three-dimensional woven polymer material with ultra-durable and absolutely uniform mesh fibers. This advanced woven mesh structure allows hot solvent molecules to circulate extremely freely while effectively retaining fine particles.
The key lies in the precise pore size of 25 microns (μm), much smaller than the standard particle size. The bag size is 52 mm x 60 mm, perfectly fitting the sample holders of current automated extraction systems. Below is a table of detailed product specifications from the manufacturer Sonnen:

Technical Specifications	Sonnen FB25 Bag Specifications
Material	High-grade heat- and chemically resistant inert polymer
Bag Dimensions	52 mm × 60 mm
Filter Aperture (Porosity)	25 μm
Packaging	100 pieces/box
Main Applications	Analysis of Crude Fiber, NDF, ADF, ADL

2.2 Superior Chemical Resistance and Thermal Stability

One of the most stringent criteria for filter membranes used in fiber analysis is their ability to withstand strong acidic and alkaline environments at reflux boiling temperatures. The Sonnen FB25 filter bag demonstrates excellent chemical resistance when continuously exposed to 1.25% (0.255N) H2SO4 and 1.25% (0.313N) NaOH solutions without crumbling, tearing, or changes in the woven fiber structure.

Furthermore, this polymer material is completely thermally inert within the drying temperature range of 102°C to 130°C. This ensures that the tare weight of the empty bag after drying and ashing remains extremely stable, without affecting the trace weight results of the remaining fiber residue.

3. Standard Operating Procedure for Fiber Extraction Bags in the Lab

3.1 Sample Preparation and Heat Sealing Steps

Step 1: Weighing the sample: Weigh 0.5g – 1.0g of the ground sample directly into the FB25 fiber extraction bag. Make sure you record the sample weight (W2) and the empty bag weight (W1).

Step 2: Heat Sealing: Use a specialized Sonnen bag sealing machine to seal the bag. Set the sealing temperature to approximately 140°C – 160°C for 1.5 – 2.5 seconds to create a flat, tight seal without shrinkage.

Step 3: Preliminary Fat Extraction (if needed): For samples high in fat (>10%), soak the sample bag in a fat extraction solvent (such as Petroleum Ether) to remove fat before fiber hydrolysis. You can find more information on this solution in the article about fat extraction bags, an important tool in the laboratory for process synchronization.

3.2 Drying, Weighing, and Calculation Correction Process

Step 4: Drying and Weighing: After the automatic or manual fiber extraction process is complete, rinse the bags with hot distilled water, then soak them in acetone to remove all water. Dry the bags in a drying oven at 102°C – 105°C for 2-3 hours, cool them in a desiccator, and weigh them to determine the mass of the bags with the fiber residue after drying (W3).

Step 5: Applying the Calculation Formula: The formula for calculating the crude fiber content (%) is corrected using the Blank Bag Correction Factor (−C) as follows:
Crude Fiber (%) = (((W3-W1.C) – W4)) / W2) . 100
(Where: W1 is the initial weight of the clean bag; W2 is the weight of the weighed sample; W3 is the weight of the bag and fiber residue after drying; W4 is the amount of ash in the empty bag after incineration)

4. Equipment Compatibility and Lab Productivity Optimization

4.1 Perfect Compatibility with Automated Fiber Analysis Systems

Sonnen FB25 filter bags are designed based on strict industrial size standards. Therefore, the product is perfectly compatible with Sonnen’s own line of automated fiber analyzers such as the F20 (automatic) and F22 (fully automatic) models.

The F20 fiber filling machine is compatible with Sonnen’s FB25 fiber filling bags

Furthermore, thanks to its standard size of 52 mm x 60 mm, technicians can easily use the FB25 filter bag interchangeably with filter bag-type fiber extraction machines from other brands on the market (such as Ankom machines) without any technical obstacles. This provides maximum flexibility for the procurement of consumables in the lab.

4.2 Economic Considerations: Optimizing Sample Throughput and Reducing Retesting

Using the filter bag extraction method offers superior economic efficiency compared to the traditional cup filtration method:
Increased sample throughput: You can process 20 to 24 samples simultaneously in the same reflux batch, instead of processing each cup individually, significantly increasing laboratory productivity.

50% Time Saving: Completely eliminates the time-consuming vacuuming step in each intermediate washing cycle, freeing up technician labor.
Minimize re-testing: Thanks to the absolute sample retention mechanism of the 25-micron woven membrane, the risk of sample loss is controlled to less than 0.1%, helping the lab save chemicals and effort to the maximum extent.

> Are you looking for a solution to improve measurement accuracy for your laboratory?

> Contact Duc Duong’s application engineering team now to receive in-depth technical advice and request a free sample of Sonnen FB25 fiber extraction bags!

> REGISTER FOR SAMPLES & CONSULTATION HERE

5. Ensuring ISO 17025 Standard and Sample Testing Program from Duc Duong

5.1 Solutions for ISO 17025 Lab Compliance

For laboratories that meet ISO/IEC 17025 standards or factories operating according to GMP/HACCP standards, the uniformity of consumables is a vital factor. Each batch of Sonnen FB25 is manufactured on an ISO 9001:2015 certified production line, ensuring extremely low empty bag weight deviation (≤1.0 mg), maximizing the reliability of micro-weighing.

Furthermore, to comprehensively control sample quality throughout the analysis cycle, especially for volatile food samples, recording storage temperature is mandatory. You can learn more about the importance of this through the article “Why modern supply chains cannot do without temperature recording equipment” for the most comprehensive understanding.

5.2 Technical Support and Sample Supply Program by Duc Duong

Duc Duong Science and Technology Co., Ltd. understands that the transition from the traditional cup filtration method to the bag filtration method requires thorough validation of the testing method at each laboratory. Therefore, we are committed to providing a comprehensive technical support program:
Providing free samples of the FB25 fiber extraction bag for customers to evaluate repeatability on their own samples.
Supporting technicians in optimizing the temperature and time parameters of the heat sealing machine.
Providing detailed standard operating instructions (SOP) in Vietnamese.

Conclusion

The transition from the traditional filter cup method to the Sonnen FB25 specialized fiber extraction bag solution is a practical technological improvement for animal feed and food laboratories in Vietnam. This solution not only completely solves the problem of fine fiber sample loss and improves the repeatability of test results to meet international standards, but also optimizes operating time for testers by up to 50%.
Contact Duc Duong today to get the most optimal consumables solution for your laboratory. Customers can register to receive detailed price quotes and bulk order discounts via the contact information below.

>> CONTACT DUC DUONG FOR DETAILED PRICE QUOTES TODAY

 

DUC DUONG SCIENCE AND TECHNOLOGY COMPANY

Address: 1014/67 Tan Ky Tan Quy, Binh Hung Hoa Ward, Binh Tan District, Ho Chi Minh City

Tel: (028) 3762 8042 – 3762 8043 – 3750 8514 – 3750 8793

Fax: 028 37628043

Email: ducduong@ducduongco.com

Website: ducduongco.com

ZALO OA: DUC DUONG SCI

 

FAQ (Frequently Asked Questions)

1.Does the 25-micron pore size of the FB25 bag slow down the filtration rate?

No. The Sonnen FB25 bag filter membrane is woven with special polymer technology that has high permeability, allowing hot acid/alkali solutions and solvents to flush out quickly under heat without the need for forced vacuum like glass filter cups.

2.Can I reuse the Sonnen FB25 fiber extraction bag multiple times?

Not recommended. Fiber extraction bags are designed for single use to ensure absolute accuracy of tare weight and avoid cross-contamination between sample batches. Reusing the material can cause fraying of the woven structure and lead to serious errors due to leftover old patterns.

3.What is the appropriate sealing temperature for FB25 filter bags?

Typical sealing temperatures range from 140°C – 160°C with a sealing time of 1.5 – 2.5 seconds, depending on the type of heat sealing machine. A standard seal should be flat, airtight, and free of air bubbles or mechanical burn marks.