Have you ever wondered what material the capsule shells of dietary supplements are made of? Where do they come from and why does the choice of capsule shell make a crucial difference? In this blog post, we will show you the different forms of capsule shells and take a look at the science behind them.
Why do we even need capsules?
To put it simply, capsules protect the ingredients from harmful external influences. The oxygen in our air can interact with the molecules and oxidize them. If you want to try this yourself, just leave a cut apple out in the fresh air for a few hours. The brown spots that form, are the result of oxidation.
To protect the valuable ingredients from the influence of oxygen and moisture, we pack them in capsules.
But why don't we just use tablets?
Capsules vs. Tablets: What are the advantages?
Tablets certainly have their advantages - they are often cheaper to produce and easier for the manufacturer to handle. But for the consumer, they can be a tough nut to crack...literally! Large or sharp-edged tablets are a real challenge for many people to swallow
Capsules, on the other hand, glide down the throat more smoothly. An advantage that should not be underestimated, especially with larger dosages or ingredients with questionable taste.
Maybe you've smelled cod liver oil or tried barley grass powder – both have an unpleasant smell/taste, and in that case, capsules are the clearly more pleasant alternative.
But it goes even further: Capsules are not only easier to swallow, they also protect sensitive ingredients like vitamins, enzymes, or probiotics from aggressive stomach acid. The active ingredients can thus reach the intestine unharmed and be optimally absorbed. With tablets, they often have a much harder time.
Another advantage of capsules: Their production usually requires fewer unnecessary additives like fillers, binders, etc. Capsules can thus offer a "purer" composition.
What types of capsule shells are there?
Capsule shells can be roughly divided into two main categories: Gelatin capsules and plant-based capsules. Within these categories, there are various variations:
- Hard gelatin capsules: These consist of two cylindrical parts that are fitted together.They are flexible and can be used for a variety of ingredients
- Soft gelatin capsules: They are commonly used for liquid or oily ingredients and are made in one piece
- HPMC capsules (Hydroxypropylmethylcellulose): These plant-based capsules are an alternative to gelatin and offer numerous advantages, as we will see shortly
- Pullulan capsules: Made from a polysaccharide derived from starch, they are vegan like HPMC capsules and provide a good barrier against oxygen
HPMC – what does the abbreviation stand for?
Hydroxypropylmethylcellulose (HPMC) is a plant-based polymer that has a range of properties that make it the best choice for capsule shells.HPMC is derived from cellulose and offers several advantages over traditional gelatin capsules:
- Vegan and allergen-free: HPMC is completely plant-based, making it a preferred choice for vegetarians, vegans, and people with allergies
- High stability: HPMC capsules are less likely to break down under varying storage conditions.They are insensitive to temperature fluctuations and humidity
- Gastric juice resistant: HPMC can be formulated to be gastric juice resistant, making it suitable for ingredients that are to be released only in the intestine
- Good bioavailability: These capsules allow for effective release of the active ingredients, which increases bioavailability
What is Gellan?
Gellan is a special gelatin substitute used to produce stable and flexible capsule shells. It is derived from natural raw materials and is commonly used in the food and pharmaceutical industries. Nevertheless, HPMC remains the superior choice as a plant-based and gastric juice resistant carrier.
Which capsule shells are vegan?
Vegetarian and vegan capsule shells are typically made from plant-based materials such as HPMC and Pullulan . These offer similar functionality to gelatin, but without using animal products.
Gelatin is usually derived from the bones or cartilage remnants of cattle or pigs.
Gastric acid-resistant capsule shells – when are they useful?
Gastric acid-resistant capsules are designed to not dissolve in the stomach but to be dissolved in the intestine. This is particularly beneficial for ingredients that are destroyed or impaired in their effect by stomach acid.This type of capsule shell can be used to ensure that sensitive nutrients or medications are released only where they are most needed.
Without the protective coating of PEG, the ingredients of our QBIOTICS would be released too early. The contained bacterium Bacillus subtilis only unfolds its positive effect in the intestine. In the stomach, the acid would kill the bacterium.
If you want to learn more about the topic, you can find more information in the article on absorption pathways.
Are capsule shells harmful? Here’s what you should pay attention to
Gelatin from China – Risks and scandals
In 2019, the Frankfurter Rundschau reported on a capsule scandal from China.There, gelatin contaminated with pollutants was produced from leather waste, which was not suitable for consumption. This gelatin contained residues of heavy metals and other potentially carcinogenic substances. This gelatin was sold for the production of medications. When inspectors wanted to check the accused company, the owner burned it down. Such scandals are fortunately rare, but they show how important regular inspections are. At MOLEQLAR, we test every batch of raw materials, among other things, for purity and residues of heavy metals. This way, we can ensure that we always meet the highest quality standards. If you want to learn more about it, you can view the individual documents on our Certificates page.
Are HPMC capsules dangerous?
For humans, the consumption of HPMC is considered safe. For us, HPMC is a water-soluble fiber that is excreted undigested. This has also been verified by several authorities, such as the Joint FAO/WHO Expert Committee on Food Additives (JECFA) and the European Food Safety Authority (EFSA). The former has established a "not specified" acceptable daily intake (ADI) for the use of HPMC in food. This means that based on the available toxicity data, there are no health concerns regarding the current use and exposure levels.
EFSA also concluded that no numerical ADI value is required for HPMC and that there are no safety concerns with the current uses and intake levels.Some studies on animals even showed a good tolerance of HPMC in very high doses of up to 7,500 mg/kg body weight per day.
So we can summarize that HPMC capsules not only offer some advantages, they are also safe.
Did you know?
You can find HPMC in many foods. Behind the number E464, you will find HPMC. In baked goods, HPMC provides improved texture, creaminess, and shelf life. It prevents drying out and is often used in frostings, spreads, and gluten-free baked goods. The versatile substance is also used as a gelling agent and stabilizer in dairy products such as yogurts or cream cheese preparations.
Dressings, sauces, and dips would often be bland and watery without HPMC. Here it helps to achieve the right creaminess and consistency.The same applies to processed meat products such as sausages, where it serves as an emulsifier and binding agent.
Why we at MOLEQLAR rely on HPMC capsules
We at MOLEQLAR are committed to outstanding quality standards, not only in the ingredients but also in the capsule shells. For this reason, we choose ultra-pure HPMC capsules. They are completely plant-based, offer high stability, and effectively keep moisture out. All these properties qualify HPMC as the ideal material for the highest quality dietary supplements. Manufacturer certificates for the capsules also ensure freedom from carrageenan or PEG.
Conclusion: Make the right choice when it comes to capsule shells
When it comes to choosing the right capsule shell for dietary supplements, HPMC capsules are unmatched due to their plant-based origin, stability, and versatility. They are not only a sustainable alternative to conventional gelatin capsules but also offer special advantages such as gastric juice resistance and improved bioavailability. Therefore, it is worth paying special attention to the use of high-purity HPMC when selecting dietary supplements to ensure that you receive a product that is both effective and ethically acceptable.
Transparent manufacturers also indicate whether their capsules are free from harmful additives. Because, HPMC is not just HPMC.
