Sunday, June 24, 2012

Honing in on homemade fuel recipe

Several months ago I wrote part 3 of a fueling for endurance events series of posts, and in that post I listed a recipe that I came up with that was pretty decent, as it provided a 50/50 mixture of fructose and glucose, as it was essentially invert sugar.

Since that post I've refined the recipe a bit and came up with what I think will be my base recipe from here on out.  Instead of having a 50/50 mixture of fructose and glucose, this recipe provides 66% glucose and 33% fructose, which is the 2:1 ratio used in Powerbars C2MAX formulation.  Part of my reasoning for wanting this mixture is that the Powerbar Ironman Perform sports drink product is currently the one being used by Ironman during their events, and since all Powerbar products use C2MAX, coming up with my own approximation seemed like a good idea.

Base recipe
2 cups water
2 cups maltodextrin (Carbogain - can be obtained from a GNC or Performance Nutrition type store)
2 cups sugar
1 TBSP acid (lemon juice or lime juice)
1 TBSP vanilla

1) Bring water to a boil. Add acid and sugar. Cover, and let simmer for 20 minutes.
2) Add in the two cups of maltodextrin and the vanilla with immersion/stick blender. The malto is much like corn starch upon contact with water - it doesn't dissolve easily, so mixing in by hand is a pain in the ass, if it's even possible.
3) Mix in flavoring, and any electrolytes (NaCl or KCl) if desired.

Result is about 3.25 cups of product.

For flavoring, I've used 1/4 cup of coca successfully, as well as one of those flavor packets for a 20 oz bottle of water. The flavor packet ended up making the batch a bit sweeter due to the artificial sweetener contained within, so next time I may try 1/2 tsp of kool aid powder.

It took me several uses before honing in on how much to take, and how much water to take it with. However, once figured out - it's easy to make, versatile, and very portable and shelf stable. The first major test was a century ride where I used this syrup for fuel exclusively once my 2 x 24 oz bottles of gatorade wore out. I specifically remember being at mile 94 and my legs still felt strong - a major difference from previous centuries where I typically bonked around mile 80-85. So it definitely works.

The geek-out info

The calorie content:

2 cups of sugar equates to about 1548 calories, and 2 cups malto equates to about 760 calories - so about 2300 calories total in the batch.
2300 cal divided by 3.25 cups is about 710 calories per cup. One cup is 8 fluid ounces, so each fluid ounce is about 89 calories.

Ratio of glucose/fructose:
Table sugar is sucrose, and sucrose is made up of 1 glucose and 1 fructose molecule bonded together. Molecular weight of 342 g/mol
Maltodextrin is 100% glucose polymers. Molecular weight varies depending on chain length, but I just went with glucose - 180 g/mol
2 cups of table sugar is 400g, or 1.16 mols of sucrose. Since 1 molecule sucrose = 1 molecule glucose + 1 molecule fructose, the end result of creating invert sugar is 1.16 mols sucrose and 1.16 mols of glucose.
2 cups of maltodextrin is 200g, or 1.11 mols of glucose.
Glucose composition = 1.11 mols from malto + 1.16 mols from sugar = 2.27 moles glucose
Fructose composition = 1.16 mols from sugar.
So, glucose to fructose ratio is 2.27:1.16 - about 2:1.

1 comment:

Fuzzbee said...

Good luck this weekend Ryan!! Kick some ass!