How Tough Is Your Capsule?

By Bob McGregor, General Manager, Brookfield Engineering

Hard and soft-shell capsules are utilized in large quantities every day in pharmaceutical and nutraceutical plants around the world. R&D departments engineer the capsule design to hold up under various forces — from the time that ingredients fill the capsule, through the packaging process, to the moment when the consumer puts it into their mouth and either bites down or swallows. Measuring the strength of the capsule is the key to qualifying whether it will survive the various forces to which it’s subjected. Performing scientific analysis to correctly characterize the forces is the first step. Using a proper test method to simulate those forces is the sequel. Physical test instruments are now equipped with an array of probes and fixtures to make these measurements and correctly assess the durability of hard and soft shell capsules.

This particular device comes out of the food industry, where it is referred to as a “texture analyzer.” Similar general-purpose instruments that perform compression and tension testing are called “universal testers.” The bottom line is that they can deform an object, like a capsule, by compressing it or pulling it apart.