"Lactose-Free" Milk Tastes Sweeter
As far as I can tell I'm not lactose intolerant, but my dad is, so I drink regular milk and he "lactose-free". I have, however, noticed that lactose-free milk is just milk with the lactase enzyme inside, so while it prevents the lactose-intolerant response, it isn't actually lactose-free.
Anyway, I have always found this lactose-free milk to seem sweeter than normal milk. Having learned some about food chemistry, I'm now wondering if this is because the lactase packaged in the milk breaks down a disaccharide (lactose) into monosaccharides, i.e. into simpler sugars, before it is drunk and therefore tastes sweeter?
I know there are some chemists on this forum - is this right?
Correct, although there are other factors. When lactose is broken both (but, mainly glucose) single sugars now are free(r) to interact with your taste receptors. The two issues are the temperature and the varying sugar % of the milk.
Most likely, the enzyme is the culprit, but there's a fair chance that your regular just has a lot less sugar than the lactose-free one.