I read on rec.crafts.brewing that "diammonia phosphate and urea" is a yeast nutrient, and the post also mentioned a "yeast energizer", speculating that it might just be vitamins. What is the difference between a yeast "nutrient" and an "energizer"?

Thanks.
Bill Velek

RESPONSE:

1) Cold Pitching, Why does it seem to work? In certain brewing forums there has been much discussion related to cold pitching yeast into ale worts. Basically, about a pint of yeast is harvested from the primary of a brew batch and stored in a sealed container at refrigerator temperatures (about 45F).