Re: Ray Peat- Gelatin, stress, longevity

Blooming gelatin refers to soaking gelatin sheets (aka leaf gelatin, gelatin leaves) or granules in cold water for a few minutes before use.The gelatin absorbs some of the water, becoming more tender and dissolving more readily in warm liquids.

Some recipes specify a specific amount of blooming water and then have you add the gelatin with the water, others have you drain off the water (in the case of gelatin sheets, squeezing out excess too), which keeps it from diluting flavors/throwing off proportions in the finished dish.

While you can add gelatin directly to liquids without blooming, you generally have to get that liquid hotter before gelling in order to prevent the gel from forming an uneven texture and/or appearance. Many of the ingredients used in fancier gelatin dishes have better colors and flavors when not subjected to this level of heat.
http://www.askmarxfoods.com/what-is-blooming-gelatin/