A bit if history before the question...I am probably going to brew up a pumpkin ale this fall and after reading a lot of different recipes and advice I was curious as to whether pumpkin needed to first be gelatinized or if it could be added raw into the mash. I found a white paper on starch properties of winter squash and came to the conclusion that pumpkin starch gelatinizes at standard saccharification rest temps, which I believe means it can be added directly to the mash without any sort of pre-cooking. I decided to add this info into the growing body of the "everything you wanted to know about pumpkin beer" thread
. In response to my post, passedpawn posted a chart of the gelatinization temps of various starches (page 21 of the aforementioned thread). Some back and forth ensued about whether or not anything special needed to be done with starches that had gelatinization temps lower than standard sacch. rests - i.e. whether or not they need to go through a cereal mash process. For example, according to the chart rye has a gelatinization range mostly under 60C. I had thought that cereal mashes were performed for those grains/starches that gelatinized at temps greater than standard mash temps. I was under the impression that for starch gelatinization you needed a certain minimum
temperature, but now I am not so sure. On that same chart, for example, oats have a gelatinization temp mostly lower than typical mash temps and everything I've read about using oats says to use flaked/rolled oats because they are pre-gelatinized - otherwise you have to cereal mash them.
So, what's the deal with gelatinization temps and cereal mashes? Perhaps I don't truly understand a cereal mash - I thought it was just cooking (i.e. boiling) the grains to allow for starch gelatinization. However, this goes against what the chart is saying in terms of gelatinization temperatures. Can anyone shed some light on this?