Choosing the right capsule format is one of the key variables that directly influences the effectiveness of dietary supplements—especially formulas containing active ingredients that are sensitive to stomach acid or easily degraded in acidic environments. Today, high-quality supplement manufacturers such as Maydi International increasingly prefer enteric capsules, which are designed to withstand stomach acid and deliver active ingredients precisely to the intestines.

This article will guide you through their key advantages, how they work, and why enteric capsules are an ideal choice for premium-grade formulations.

What is an enteric capsule?

Enteric capsules are designed not to disintegrate in the stomach, where the pH is approximately 1.2–3.0. They begin to break down only after reaching the duodenum or mid-small intestine, where the pH is higher (around 5.5–7.0).

The capsule walls are typically made from acid-resistant polymers, such as:

• Enteric-grade HPMC (Hydroxypropyl Methylcellulose)
• Pullulan with special enteric coating
• Methacrylate polymers (used in advanced formulations)

These polymers remain stable in acidic conditions but disintegrate quickly once exposed to the alkaline environment of the intestine.

How does a capsule work?

After ingestion, acid-resistant capsules pass through the stomach without breaking or deforming. Once they reach the intestines where the pH begins to rise, the capsule wall starts to disintegrate and releases the active ingredients through targeted release. This helps to:

• Protect the active ingredients from being destroyed by stomach acid
• Enhance the absorption of ingredients that are better absorbed in the intestines
• Reduce gastric irritation caused by ingredients that are easily irritating

Which type of formulation is it suitable for?

Enteric capsules are ideal for ingredients that are unstable in acidic conditions or those intended to be absorbed in the intestine, such as:

• Probiotics
• Acid-sensitive enzymes such as bromelain and papain
• Certain types of omega-3 that have a fishy odor
• Vitamins or extracts that are sensitive to heat and acidity
• Ingredients that may irritate the stomach, such as certain herbs or minerals

Benefits of acid-resistant capsules

• Enhances the stability of active ingredients
• Prevents premature degradation
• Improves absorption efficiency by delivering the ingredients to the targeted area
• Ideal for premium products that require high quality
• Reduces unpleasant odor since the capsule does not break in the stomach
• Helps minimize acid reflux or gastric irritation caused by certain formulations

The reason Maydi International uses acid-resistant capsules for premium-quality products.

Maydi International provides comprehensive OEM/ODM supplement formulation and manufacturing services. With our expertise in product dosage forms that require acid protection or targeted delivery to the intestines, we use internationally certified capsule materials that have been tested and verified by SGS, such as

• GHPs
• HACCP
• ISO9001
• ISO22000

Our R&D team evaluates the properties of each active ingredient and selects the most suitable capsule type to ensure your product delivers maximum efficacy from the very first dose.

Suitable for brands that require premium-level quality.

If you want to build a truly differentiated supplement brand, choosing acid-resistant capsules gives you a clear advantage — from enhanced efficacy and targeted release to a more premium product image.

Maydi International is ready to support you with end-to-end consultation on ingredient selection, capsule formats, and formulation development, ensuring your product enters the market with confidence.