Fibre is measured in a laboratory using an enzymatic-gravimetric method.
Understanding the Enzymatic-Gravimetric Method
This method is designed to mimic the way our digestive system processes food, providing an accurate measurement of dietary fiber content. Here's a step-by-step breakdown:
- Defatting: The food sample first undergoes a defatting process. This removes any fats that could interfere with accurate fiber measurement.
- Enzymatic Treatment: The defatted sample is then treated with specific enzymes that simulate the digestive process in the human small intestine. These enzymes break down the digestible parts of the food.
- Gravimetric Analysis: After enzyme treatment, the remaining undigested material, which is mainly the dietary fiber, is separated, dried, and weighed. This measurement provides the total amount of dietary fiber in the sample.
Key Aspects of the Measurement Process
- Accuracy: The enzymatic-gravimetric method is considered highly accurate because it replicates the actual digestive process.
- Specificity: The enzymes used are specifically chosen to target digestible carbohydrates, leaving the fiber component intact.
- Relevance: This method gives a realistic measurement of how much fiber would be available for our digestive systems, unlike chemical-based methods.
Why Use This Method?
- Mimics Digestion: Unlike other methods, it mirrors the physiological digestion process in humans.
- Provides Actual Fiber Content: It isolates and quantifies the undigested part of the food, which is by definition fiber.
- Widely Accepted: The enzymatic-gravimetric method is recognized as the standard method for determining dietary fiber content in food samples.
In Summary
The enzymatic-gravimetric method is a precise and reliable way to measure fibre. By simulating digestion in the lab, it allows accurate quantification of dietary fiber. The defatting process ensures that fats don't skew results, followed by the enzyme breakdown of digestible components, with the remaining residue dried and weighed to give us the dietary fiber content.
