Packets of artificial sweeteners typically say something like “Sweet as 2 teaspoons of sugar”. Is this something that can be quantitatively measured in a laboratory? Or is it merely the consensus of the manufacturer’s taste-testers?
Many sweet things are measured in
Brix, which is actually a measure of dissolved sugars. I don’t know of any sort of scale that compares sweetness between chemically different substances, though.
Brix: a measure of fruit sweetness | Dave Wilson Nursery.
There’;s a scale of “percent sucrose equivalent”, but I suspect it all comes back to a human taster
The Sweetener Book.
The taste of sucrose is our familiar basis, the ‘gold standard’ of sweet taste. Its sweetness profile includes a certain rate of sweetness onset, a maximum impression, and a prompt fading out, conditions that are not matched perfectly by other
sweeteners. We all are conditioned almost from birth on sucrose sweetness and recognize any deviation from that sweetness profile. Sweetness with a delayed onset or with an aftertaste is generally disliked, mainly because it is unfamiliar compared to sucrose.
The only way to compare it to other sweeteners is through sensory comparison, mostly done by tasting in solutions, either 10% of sucrose in water or to some other percentage. In the comparison, sucrose is given the value of either 1 or 100. The tasting procedure is carried out under defined conditions. Factors affecting the sweetness impression, besides the concentration, are the temperature, pH, the presence of other components, the sensitivity of the individual, and if the individual is trained or untrained (Nordic Sugar, 2009). A higher temperature, for example, reduces the sweetness impact of fructose considerably.
Karl F. Tiefenbacher, in
Wafer and Waffle, 2017
Scoville rating for hot peppers and the like was also defined based on human tasters. Nowadays, for capsaicin (the key ingredient in chili peppers), it’s normalized to the chemically-measured capsaicin levels, but you can still use human tasters to define a Scoville equivalent for other spicy chemicals.
I only knew about Brix because a good friend was a winemaker. Sugar content is important there!