How to make a sweet potato even sweeter: freeze it before baking

Studies show it is always best to bake your sweet potatoes, rather than boil or microwave them, and there is another trick to take the tubers to the next level of deliciousness, says Sam Wong

By Sam Wong

DELICIOUS meals don’t get much simpler than a baked sweet potato. But a little science can tell us how to maximise this dish’s sweetness and deepen its flavour.

Sweet potatoes are between 1 and 2.5 per cent sugar when raw, but they get sweeter as they cook thanks to the work of amylase enzymes that break down starch into simple sugars. These enzymes are most active at 75°C (167°F).

A study from 2012 found that the sugar content of one type of sweet potato was almost five times higher after baking for 90 minutes, mainly due …