Having trouble with the sweet & sour sauce recipe Recipe here: http://allrecipes.com/recipe/19670/sweet-and-sour-sauce-i/

Ingredients:
3/4 cup white sugar
1/3 cup white vinegar
2/3 cup water
1/4 cup soy sauce
1 tablespoon ketchup
2 tablespoons cornstarch

Directions:
Place the sugar, vinegar, water, soy sauce, ketchup and cornstarch in a medium saucepan, and bring to a boil. Stir continuously until the mixture has thickened.


I did everything as said in the instructions, weighed in all the ingredients correctly and the problem is with the vinegar. I don't know if I'm using the wrong vinegar or something, but as soon as I smelled the sauce when it was cooking, I thought my lungs was about to explode in my chest, I could barely taste the sauce as the vinegar felt really really strong in it.

Is it something wrong with my choice of vinegar or is the recipe faulty? I don't understand. On the bottle it says "Food vinegar acid (9%)".

Really need help.
5% is the acid content of most common vinegars, and if a recipe doesn't explicitly state to use a stronger one, assume a 5% type is intended. There seem to be versions of white distilled vinegar in both 5% and 10%, an even stronger version called Essigessenz at 25% (!!!) is common in Germany. You likely bought the 9% version by accident, you should dilute it 1:1 with water or only use half the amount.