Proteolytic and Antioxidant Enzymes Stability can be a major problem with enzyme products. Upon actual assay, many products labeled to contain proteolytic or antioxidant enzyme activity were found to be sub potent or completely devoid of activity. From these lessons, we learned to procure enzymes from only the most reputable of sources, and use state of the art in-house quality control to ensure enzyme activity in finished products. Smaller batches are produced on a frequent basis in order to consistently provide fresh products. Although our approach is more complex, it results in products that are consistently of higher quality and reliability.