How We Ensure Clean Herbs - Part 1: Microbiologicals

How We Ensure Clean Herbs - Part 1: Microbiologicals

Teresa Williams
There are many reasons to choose Whole Herb Extracts, but many discerning wellness brands buy our herbs exclusively because of the exceptionally low levels of contaminants in our herbs.  Today, we focus on why our products have such low levels of bacteria, mold, and yeast present in them.
While some companies use a dedicated "kill step" during the production process to achieve specific microbiological limits, we have no need to do so because of the holistic process we take to ensure the freshest and cleanest herbs possible.  Here are six of the steps that optimize the efficacy of our herbs while also reducing the opportunities for microbiological substances to grow.


1. Direct Sourcing

We control the quality of raw herb ingredients starting with planting and harvesting and we purchase raw herb materials directly from over 300 farms.  After the herbs are harvested, they are sent to one of thirteen regional processing facilities to be washed, dried, and processed using traditional techniques as needed. 

Most other herbs, in contrast, are sold through wholesale herb markets or middlemen that both extend the amount of handling and the time in storage the herbs experience. The longer the herbs are stored, the more opportunities for bacteria, mold, and yeast to grow. 

2. Proper Storage

Once dried, herbs are packaged, transported, and stored at our supplier's facilities outside Shanghai, China. There are two dedicated warehouses for incoming materials: a temperature-controlled warehouse for the majority of the raw materials, and a refrigerated warehouse for herbs with high sugar content or are otherwise more prone to decay.  In both cases, a sample of each batch is tested for microbiological organisms before the materials can be accepted into production.

3. High-Temperature Decoction

Once in production, the herbs are decocted in pure water to extract the active chemical components.  The decoction time and temperature (100℃ or higher) are used for extraction to effectively kill microorganisms.

4. Close Loop Handling

The extraction liquid is then transported via a sterile, closed pipeline between separation, concentration, and spray dry processes. The air temperature in the spray dry chamber is between 160° C and 190° C, which is inhospitable to microorganisms.

5. Cleanroom Environment

Then, the dry powder extracts are collected in a production environment that is a Class D cleanroom, which is strictly controlled for the presence of airborne particulates and pressurized to ensure that any contaminants flow out of the cleanroom rather than in.  

6. Intermediate & Final Testing

The herbs are again sampled and laboratory tested to ensure that the microbial levels meet pharmaceutical standards before they are permitted to continue forward in the production process. 

Following granulation and packaging, the finished herbal extracts are tested a final time according to international standards. The microbial tests are conducted in a national-level laboratory certified by CNAS to ISO/IEC17025 standards.


The controls described above are components of a comprehensive quality control program that allows our products to meet and exceed China’s standards for pharmaceuticals and US standards for dietary supplements. 

Stay tuned for Part 2, in which we discuss our highly effective controls for environmental toxins, like heavy metals, aflatoxin, and sulfur compounds!