What you've said puzzled me a little. If sweeteners decrease concentration of ClO2 they must be antioxidants... I've checked it and that's right, they are antioxidants:
There were 2 links, but this forum claims they are spams, which they aren't. I'll just put titles of this documents:
"Sugar as a source of antioxidants?"
"Total Antioxidant Content of Alternatives to Refined Sugar"
It seems white sugar is the weakest sweet antioxidant. I haven't tried syrups. I had no need... out of the sweet things I like the most bacon
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