Water activity meters help pharmaceutical quality control specialists measure the amount of water activity within individual units before they are packaged for distribution. The water activity levels have a direct impact on the finished product’s properties.
How is Water Activity Measured?
Water activity (or Aw) is measured using a specialized device that can determine the amount of available water within an individual product. Most often, Aw is measured during quality control of non-sterile pharmaceuticals.
The industry standard for measuring a product’s Aw is on a scale of 0.00 to 1.00. If something has an Aw of 0.00, this means it is completely dry and waterless. The contents of a bottle of water, for example, would have a reading of 1.00 because it is pure water. An Aw of 0.80 would mean that the item being examined has a vapor pressure of 80% of pure water.
What Happens if the Water Activity is Too High?
If a pharmaceutical product has too high of a water activity level, this can create an environment that encourages microbial growth. In turn, this shortens a product’s shelf life, can cause clumping, can change its texture and puts consumers at risk of contact with contaminated goods.
What Happens if the Water Activity is Too Low?
Conversely, products with too low of an Aw reading can dry out prematurely. This can change taste, texture, and may alter the effectiveness of the product. For example, if a gummy vitamin is too low on the Aw scale, it can harden and become difficult to chew.
How Water Activity Affects the Consumer Experience
Beyond generally creating an increased risk of microbial growth, water activity can affect different types of pharmaceuticals in specific ways:
Texture
Because improper water activity levels can affect the texture of a product and can cause clumping, this can create an unpleasant texture. For example, a gummy with too high of an Aw level can be too mushy and sticky. Conversely, one with too little water can be hard, tough, and difficult to chew.
Dosage
If water activity causes the products to stick together, this could potentially mislead someone into taking too great of a dose of a product. This can create a severe safety concern and put consumers at risk of taking too large of a dose.
Product Integrity
Many pharmaceuticals have brittle coatings that are designed to dissolve in liquid. Capsules, softgels, and tablets could all degrade far more quickly if the Aw levels are too high. Others with too little water may crack and spill their contents into the container.
What to Look for in a Water Activity Meter
There are a wide variety of water activity meters on the market that quality control specialists can use to read the Aw of a pharmaceutical product. However, not all of them are created equal. Here are some key features to look for:
Portability
When moving around a large production facility, having a portable device that can provide QC specialists with a quick and accurate read is essential. A portable meter should be lightweight and easy to fit in a bag or pocket.
Speed
When you have to measure the Aw levels on multiple products each day, you need something that can provide the reading without much wait time. Ideally, the device you use should produce accurate data within 5 minutes or less.
Easy to Read
Many water activity meters also provide temperature readings. An effective water activity meter should provide you with all the information you need to assure quality within a single screen readout.
Digital Connectivity
Once you’ve gathered your data, you need to be able to store it in your central database with the rest of your quality control documentation. An effective water activity meter should be able to connect with a computer to process your acquired data, both wired or wireless.
Get a Better Water Activity Meter for Your Operations
With a precision of 0.02 Aw and lightweight portability, our Water Activity Meter is designed with the needs of pharmaceutical quality control specialists in mind. With a design weighing less than a mobile phone, you can easily carry your water activity meter throughout your facility and acquire accurate readings within minutes.
Have more questions about our Water Activity Meter or other quality control equipment? Contact us any time to speak with one of our team members.