The Pure Probiotic Initiative:
Probiotic Manufacturing: Moisture Control

By Kelly C. Heim, Ph.D.

Probiotics are living cells with unique requirements for survival. Outside of the body, where nutrients and water are not available, these bacteria must remain in a metabolically dormant state to survive. During manufacturing, moisture and heat can disrupt this quiescence, decreasing stability. As the production environment cannot requite these demands, loss of viability ensues.

Probiotic stability can be maintained by minimizing temperature and moisture.^1,2 Pure Encapsulations operates within a specific temperature range throughout all stages of receiving, handling and manufacturing. Moisture, the most critical variable, is controlled in the facility, as well as within the material itself to ensure finished product potency. Pure Encapsulations’ probiotic manufacturing process limits exposure to ambient moisture through 4 strategies:

1. Humidity control. Relative humidity is monitored and recorded in all rooms every two hours, including the warehouse, walk-in coolers and every production room, and operations proceed only within specific limits.
2. Tempering. Condensation, which can be lethal to probiotic cells, is minimized by a procedure known as tempering. In this process, stored raw material is gradually adjusted to the manufacturing temperature prior to blending and encapsulation.
3. Low-exposure blending. During the blending process, compressed, dry air is used at a low, tightly controlled dew point, such that condensation is nearly impossible. An alarm sounds if the reading is out of the specified range.
4. Efficient timing. Sensitive steps in manufacturing are conducted within short time frames as an additional protective strategy.

While systemic control of ambient conditions is fundamental, this practice alone does not always guarantee finished product viability. Moisture within the blended material itself is an equally imperative consideration.³ Traces of water inherently present in the powder of any ingredient can disrupt quiescence and reduce stability. To minimize moisture inside the product itself, Pure Encapsulations probiotics are formulated with minimal water activity (A_w). This is a thermodynamic value that specifically refers to the amount of water available to microorganisms. High A_w values of prebiotics such as FOS (A_w=0.15), and common fillers (A_w >0.3) impart destabilizing effects in probiotic formulations. Conversely, Pure Encapsulations’ probiotics are formulated with a proprietary rice base with a very low A_w of less than 0.1. The rice base affords greater potency compared to a high A_w cellulose filler (A_w=0.39) (Figure 1). Together with rigorous temperature and humidity specifications for all stages of production, low-A_w formulation helps to ensure the stability of the finished product.

Figure 1. Some forms of cellulose can compromise potency. By virtue of its low water activity (A_W), a hypoallergenic rice base maintains stability, resulting in a higher potency after manufacturing.

Strategic moisture control, applied throughout every phase of handling and manufacturing, represents one of many facets of Pure Encapsulations’ long-standing commitment to excellence in probiotic innovation and quality assurance. This dedication and promise ensures that practitioners can be confident in the potency and reliability of each probiotic product through its date of expiration.^‡