Zinc is a key component at the active site of several yeast enzymes, most notably alcohol dehydrogenase. In most worts the zinc content is relatively low and therefore many brewers add it (typically at 0.2 ppm) to stimulate fermentation. Some options for the brewer to enhance the zinc content in wort are as follows: Adding zinc salts to the boiling wort Using zinc-enriched yeast Incorporating zinc plates into the wort kettle
Adding zinc salts to the boiling wort
Using zinc-enriched yeast
Incorporating zinc plates into the wort kettle
Zinc at higher levels (e.g., 2 ppm) is very beneficial to beer foam stability and cling, probably through an involvement in the bridging of hydrophobic polypeptides with iso-alpha acids.
Zinc is also beneficial for the human body and is used in many medications. One of the richest stores of zinc in the body is the prostate gland.