The two primary types of thickeners
There are two primary categories of thickeners available for managing dysphagia: gum-based and starch-based. These ingredients are polysaccharides, which are large carbohydrate molecules designed to hold water and create a cohesive, viscous fluid. Understanding the base material is key to knowing how it will behave when mixed with liquids and consumed by a patient.
Gum-based thickeners
Modern thickeners often utilize gums to achieve the desired consistency. Xanthan gum is the most common example, a polysaccharide produced by the bacterium Xanthomonas campestris. It is highly effective at thickening liquids at low concentrations, making it a cost-effective choice.
- How it works: Xanthan gum molecules create a tight, entangled network when hydrated, which keeps the fluid's viscosity stable. This network is also resistant to breakdown by salivary amylase, an enzyme in saliva that can thin starch-based products.
- Advantages: Gum-based thickeners produce a smooth, tasteless, and transparent result. Their consistency remains stable across various temperatures, pH levels (such as in juices), and over time, allowing for longer serving periods.
- Potential drawbacks: Some xanthan gum formulations can create a 'slick' or 'slimy' texture that some patients may find unappealing. There can also be interactions with certain medications, potentially affecting drug absorption.
Starch-based thickeners
Starch-based thickeners have been used for a long time and typically consist of modified cornstarch or maltodextrin.
- How it works: The starch granules absorb water and swell, increasing the liquid's viscosity. This process is different from the molecular network formed by gums.
- Advantages: These thickeners are widely available and relatively inexpensive. They are easy to find and may be familiar to some users.
- Potential drawbacks: A major issue with starch-based thickeners is their instability. The amylase in human saliva can break down the starch molecules, causing the thickened fluid to become thin again in the mouth, which creates a significant swallowing risk. They can also develop a grainy texture, a starchy aftertaste, and a cloudy appearance. Finally, their consistency can change over time as they sit.
Other common and alternative thickener ingredients
Beyond the two main types, other ingredients are sometimes used or combined to create dysphagia products:
- Guar Gum: A galactomannan derived from guar beans, guar gum is another water-soluble fiber used to increase viscosity. It is sometimes blended with xanthan gum to provide a synergistic thickening effect.
- Carboxymethylcellulose (CMC): This is a cellulose derivative that functions as a thickener and stabilizer. It is less common than xanthan gum in dysphagia products but is used in various food applications.
- Maltodextrin: Often found in starch-based thickeners and some gum blends, maltodextrin acts as a bulking agent. It adds calories but has limited thickening power on its own.
Comparing gum-based and starch-based thickeners
| Feature | Gum-Based Thickeners | Starch-Based Thickeners |
|---|---|---|
| Primary Ingredient | Xanthan gum, guar gum, etc. | Modified cornstarch, maltodextrin |
| Stability in Saliva | Resistant to salivary amylase; stable consistency | Thins rapidly due to salivary amylase |
| Mixing Time | Hydrates quickly | Takes longer to reach full consistency |
| Viscosity over time | Stable; holds its thickness consistently | Continues to thicken as it stands |
| Clarity | Often produces a clear or near-clear liquid | Can make liquids appear cloudy |
| Texture | Generally smooth and 'slick' | Can have a grainy or gritty texture |
| Taste | Neutral or tasteless | Can impart a starchy aftertaste |
| Temperature | Stable across wide temperature ranges | Less temperature stable |
| Medication Interaction | Potential for interaction with some drugs | Less preferred due to instability in saliva |
The importance of choosing the right thickener
Choosing the correct thickener goes beyond just reaching the right consistency. It is a critical component of a dysphagia management plan tailored to the individual's needs, often overseen by a Speech and Language Therapist. The right choice can improve compliance, hydration, and overall mealtime experience. In contrast, a poor choice can increase the risk of aspiration pneumonia, medication issues, or dehydration due to reduced fluid intake from poor palatability.
Different types of thickeners have different strengths. For instance, gum-based thickeners are generally preferred for their stability and resistance to salivary enzymes, which provides a more predictable and consistent viscosity during swallowing. This reduces the risk of the liquid becoming dangerously thin during consumption. Some modern, gum-based thickeners even come in a clear, pre-hydrated liquid or gel form for added convenience, eliminating mixing challenges.
For some patients, a blend of thickeners might be necessary to achieve the desired result, combining the positive attributes of both gum and starch components. The International Dysphagia Diet Standardisation Initiative (IDDSI) provides a framework for classifying thickened liquids to help ensure a consistent approach to dysphagia management worldwide.
Conclusion
What is thickener for dysphagia made of? The answer lies primarily in two material types: gum-based thickeners, like xanthan gum, and starch-based thickeners, such as modified cornstarch. Gum-based options are generally favored for their superior stability and texture, resisting thinning by saliva and maintaining a consistent viscosity over time. Starch-based alternatives are less expensive but prone to degradation by saliva, which increases the risk of aspiration. A combination of these thickeners or other additives like maltodextrin might be included in a final product formulation. Ultimately, the selection of a thickener should be based on an individual patient's needs and preferences, in consultation with a healthcare professional, to ensure safety and improve quality of life. For further reading on the international guidelines for dietary modification, visit the IDDSI website. [https://www.iddsi.org/standards/framework/]
