cooking with fructose - advice please!
Can anyone share any experiences they've had cooking with fructose as a sugar replacement?
Does it 'work' the same as normal sugar in baking;
Are there certain types of cooking it does not suit;
Does it make food taste different;
In what proportions should I substitute (1/2C fructose for 1C sugar?);
and finally (for diabetic chowhounds) how have your blood sugar levels responded to fructose versus artificial sweeteners like Splenda?
Well, Fructose is sugar. It's a basic natural sweetener from corn. It has a yellow tint to it though, so if you're going to use it to "substitute" in baking, you may want to use it for something that is not clear/white. But, Fructose is a good sugar base to use as a caramelizer. You can use it to darken a dish as well, and to make a thicker consistency in things like pudding and creme brulee.
The box says 2/3 of the normal sugar amount. My wife makes apple pie with it and has good luck following those instructions.
My warning as a diabetic is twofold:
1) Fructose isn't necessarily good for you. It keeps blood sugar low because it doesn't get stored, but it goes right to the liver for processing (like alcohol). I've read several articles warning against overuse. In her book, Nourishing Traditions, Sally Eng warns against Fructose, including HFCS - she sites one study that linked tumor growth to fructose. She especially warns about exposing young growing children to too much fructose.
2) You can easily get into the problem of thinking that something is now ok to eat, where it wasn't before, and have this cause problems because you're not looking at the whole picture. Where I would not eat a slice of normal apple pie - maybe just take a bite - I would eat a whole slice of the fructose pie. Problem was that the GI (Glycemic Index) of the fructose slice was almost as high as the normal slice due to the amount of refined flour in the crust. My blood sugar would go sky-rocketing and I would think that the fructose wasn't working. In the long run, you need to understand that making yourself happy with just the bite is much healthier than eating a slice, no matter what magic ingredients you used.
I highly recommend the book and accompanying series "The (New) Glucose Revolution" - they have a special pocket guide for diabetics. They discuss how to determine and use the GI (Glycemic Index) - or how fast a food converts to sugar in your blood - as a way to monitor your diet. There is an excellent chapter on what factors affect the rate of absorption of glucose.
Not sure where you're getting the "fructose keeps blood sugar low" notion. As always, among folks with Diabetes, we say, YMMV, or your mileage may vary. I'd be skeptical on this, though I might try it. I'd expect fructose to have just about the same effect on my BG as table sugar.
From "The New Glucose Revolution":
"THE EFFECT OF SUGAR ON THE GLYCEMIC INDEX
Table sugar or refined sugar (sucrose) has a GI value of only 60-65. This is because it is a disaccharide (double sugar) composed of one glucose molecule coupled to one fructose molecule. Fructose is absorbed and taken directly to the liver where it is immediately oxidized (burned as the source of energy). The blood-glucose response to pure fructose is very small (GI value of 19). Consequently, when we consume sucrose, only half of what we've eaten is actually glucose; the other half is fructose. This explains why the blood-glucose response to 50 grams of sucrose is approximately half that of 50 grams of corn syrup or maltodextrins (where the molecules are all glucose)."
You're absolutely right about YMMV - that's why I have so many holes in my fingers (as do all of us, types 1 and 2 alike). The reason why the GI works and is important for diabetics is that there are lots and lots of reasons why glucose absorbs at different rates. For example, pasta isn't as bad as one might assume from it's make-up of refined carbs because the gluten coats the carb molecules and allows slower digestion.
The GI is developed by actual experimentation. People are fed particular items and their blood sugar is checked often, and the profile is recorded. This is done across all types of people in many countries. So if fructose is said to have a GI of 19, most people had a lower increase of blood sugar than they would have with glucose (100) or table sugar (60-65).
But YMMV! You might want to try it for yourself, as you suggest. Take a teaspoonful of table sugar in a glass of water and read your Blood sugar at 30 minutes and 2 hours. The next day, at the same time, and assuming your daily readings were the same, do te same with a teaspoonful of fructose. It should be a much smaller peak, and the overall effect should be less.
Nevertheless, I'd definitely not recommend a wholesale switch to fructose from all things sucrose - certainly this is not a strategy that has been widely recommended by anybody. And even simple one-off experimentation - like with the apple pie - needs to be done with some forethought. (To avoid what I went through!)
The book is well worth getting for anybody, but especially for diabetics, even if its just for the GI listing of various foods. It does a great job of explaining all the types of carbs and all the reasons why glucose is absorbed at different rates. I've included a link for the site that offers the book and a bunch of additional material.
"This explains why the blood-glucose response to 50 grams of sucrose is approximately half that of 50 grams of corn syrup or maltodextrins (where the molecules are all glucose)."
WTF is this crap? Typical HFCS contains LESS fructose than sucrose (Common HFCS is 42% fructose, sucrose is 50% fructose).
And you do realize that fruit contains fructose, right? That's why it's called FRUctose. So you stopped eating fruit?