Preparation of a Beverage Containing Freeze-Dried Watercress for a Clinical Trial of Carcinogen and Toxicant Detoxification.

Unlabelled: Watercress is an excellent source of phenethyl isothiocyanate (PEITC), shown in many studies to enhance carcinogen and toxicant detoxification and to inhibit carcinogenesis. Based on a previous observation that PEITC can enhance the detoxification of common environmental pollutants such as acrolein, crotonaldehyde, benzene, and 1,3-butadiene, we designed a clinical trial testing the hypothesis that daily consumption of a drink containing freeze-dried watercress, an abundant source of PEITC, would have a similar effect, particularly observed in subjects who were null in certain glutathione S-transferase genes. This manuscript describes the preparation of nearly 100 pounds of freeze-dried watercress for this trial, starting with laboratory-scale pilot studies and proceeding to industrial-scale production of the fully validated product in compliance with all food safety requirements.