Excipients (Fillers, Binders and Flow Agents)
During the supplement manufacturing process, excipients play an important role in producing high quality, consistent tablets, capsules and softgels in a cost effective manner. Excipients are a class of raw materials that includes fillers, binders and flow agents.
What Are Fillers?
Fillers are generally used to take up additional space that may be present in the tablet, capsule or softgel. The capsules used in manufacturing vitmains and supplements come in a variety of standardized size. Without fillers, capsules may end up looking “half-full,” as the amount of the dietary ingredient used may be too much for a capsule that is a size smaller, but is not enough to fill the volume of the capsule the next size up. Softgels and tablets use carrier oils and fillers when the dietary ingredient may not be of a sufficient volume to fill the manufacturing die completely, which would result in poor quality softgels and tablets.
As batch size is often limited by the blender capacity, using less filler is more advantageous from a manufacturing standpoint. Unfortunately in most situations, fillers cannot be completely avoided. Common fillers used are rice flour, microcrystalline cellulose, starch and calcium phosphates. Carrier oils may come from a variety of sources such as soy and other vegetable oils.
What Are Binders?
Binders are used during the tableting process to ensure that the tablet compresses and binds properly. Without the appropriate amount of binder, a tablet may break apart easily, chip, crack or crumble. Some raw materials such as cellulose and calcium phosphate may serve dual roles as both a filler and a binder.
What Are Flow Agents?
Flow agents (also known as glidants and lubricants) are used to enhance the ability of an ingredient or product to flow and reduce stickiness of dietary ingredients. Some flow agents can also serve as densifiers, helping particles fit together better, which results in a smaller capsule or tablet that would not be possible without the flow agent. Many flow agents are effective when used at very low levels (under 1%) in a blend. Different flow agents perform different functions when added to a blend. Silicone dioxide (silica) is effective at reducing stickiness of powders, while magnesium stearate is more effective at preventing build-up on machine surfaces and improving the flow/compaction of powders. Other types of flow agents include stearic acid, rice bran extract, calcium laurate, talc or calcium palmitate.
Whenever possible, we manufacture products without using flow agents; however, some products can simply not be made without them.