We asked Soil Foodweb Inc. to design and conduct a study evaluating the effectiveness of the Hiwassee Products Bio-Extractor at extracting biology from compost. They ran 10lb batches of compost through the Bio-Extractor at five different auger speeds and extracted a batch of compost using the brewer method as a control. The concentration of microorganisms in the different extract batches was determined using the Soil Foodweb microscopy method. In addition, the concentration of microorganisms in the input compost was compared to the spent compost to calculate the expected extract concentration. The expected concentration was compared to the actual extract concentration to evaluate the extractor’s ability to extract viable microorganisms.

Here are the results of the study summarized

• Depending on the auger speed, the Bio-Extractor is as efficient or more efficient than the brewer method.
• Lower auger speeds are more efficient at extracting biology, but higher speeds yield more concentrated extract, so the optimal speed depends on the intended application.
• Extract from the Bio-Extractor contained more biology than was predicted by analyzing the compost before and after extraction, sometimes resulting in experimental efficiency of over 100%.