Chestnuts - Processing into Flour

From the good folks at Sunshine Coast Sustainability:

Annie Y. BhagwandinThe nuts mold quickly after they are gathered. If you can't husk them right away, then they must be refrigerated. There are many ways for storing and drying chestnuts. There is a great book that we have. I think it's called "the chestnut cookbook" by Annie Y. Bhagwandin, that goes through all the various ways to store your crop, plus stories on the history of the tree and recipes. Very good book. 
      These nuts need a quick drying out because of their high water content and mold issues. So we use the oven. We chop them into quarters and dry in the oven at 170-190 degrees Farenheight for 3 or more hours. They should be hard and dry. During cooking/drying you have to watch closely for them to brown. If they start to brown then turn the oven temp lower. For optimum health benefit, nuts are best not roasted ..... But chestnuts actually are very low in fat,which is why they are so different than other nuts. They behave much more like a grain, than a nut. Ideally, you could use a conventional dehydrator, it just takes longer and we like the roasted flavor that then oven gives for this particular crop. Chestnuts actually get extremely hard after the drying process. If your using them right away, then you needn't worry about how completely dry they are, but if your drying a lot and need to store them, then they must be totally dried out. We leave them out on trays in the front window for the rest of the day plus overnight to ensure they are completely dried out. Then we store in mason jars. They can store like this for a very long time. Then we use our flour mill to grind them. These nuts are so hard that a food processor or spice grinder simply does not work. Apparently, you can soak dried chestnuts like you do beans and then boil like potatoes to soften the next day and use mashed in recipes, however, we have not tried this method as we have a very high grade hand powered flour mill. You could try this method if you don't have a mill.

http://www.chestnutbrook.com.au/chestnuts-nutritional-value.html

The nutritional composition of the chestnut as compared with the apple is shown below:
Per 100g Fresh Fruit : Australian grown chestnuts

Constituent	Chestnut	Apple
Water  (g)	48.2	84.8
Protein  (g)	3.4	0.2
Fat  (g)	0.2	0.1
total Carbohydrate (g)	32.1	14.0
Sugars (g)	3.3	1.0
Energy  (kJ)	730	230
Dietary Fibre (g)	14.9	0.1
Calcium (mg)	17.6	7.0
Zinc  (mg)	0.4	88
Iron (mg)	0.7	0.3
Sodium (mg)	0.8	1.0
Potassium (mg)	468	110

Source: Silliker Microtech 2002

Chestnuts contain no cholesterol and are low in sodium, fat and kilojoules. They are rich in mineral salts and a good source of vitamins C, B1 and B2 and folates.  An average 30g serve provides only 200 kilojoules.