Just like the test for yeast infection is weird ((for yeast infection, the only truthful test is to kill off yeast by restricting all carbohydrate intake for a LONG while... if you respond with intestinal pain, gas, general malaise, then your intestines were full of yeast aka Candida)).
The way to test for fructose is to buy fructose and consume it instead of regular sugar however you normally consume sugar.
Lemonade, your tea/coffee, bake with it, make ice-cream, just make sure you don't use more of it than you would use of regular sugar.
Watch your reaction... the reaction, if you are intolerant or sensitive, will be almost instant.
Diarrhea, constipation, stomach pain... unless it is regular for you, are all indication of the dietary change.
Someone who is not sensitive to fructose, would not notice any difference.
Now, if you are not sensitive to fructose then you are allowed to eat fruit... and if you are, then I have a recommendation for you I found yesterday... just know that I envy you... 🙁
This is a frozen fruit treat maker, no sugar, just fruit, much like a sherbet or ice cream... I love this stuff, but alas, can't eat fruit in any form. Click on the picture, it will take you to a page where you can learn more about it.