Go to any REI, outdoor store, etc... doesn't have to be an LBS and buy a tube of Nuun. Put one tab in your water bottle and stick the tube in your seat bag or pocket. It tastes like flavored water, basically, mild, and no sugar. You'll get electrolytes with no sugar. Bring a small ziplock of your dates and almonds, or maybe a piece of whole wheat bread with some kind of nut butter, or both.
For 46 miles under those conditions, you shouldn't need more than that.