Rare sugar is a rarely occurring monosaccharide (the simplest form of sugar) in the natural world. There are over 50 varieties of these simple sugars.
In the natural world,there are only 7 of these kinds of sugar that occur in large amounts, including glucose (grape sugar), fructose (fruit sugar), and so on. The remaining types are all rare sugar.
Research into producing new kinds of rare sugar is ongoing, and the possibilities seems limitless.
The size of each sugar's respective circle represents the relative amounts present in the natural world.
There may only be a small quantity of rare sugar, but it is rich in variety.
Industrial Technology Center & Fermented Food Research Institute
When looking at the average person’s diet, we know there are already trace amounts of rare sugar present in the foods people enjoy daily.
Research into rare sugar in food is mainly being conducted by the Kagawa Prefectural Industrial Technology Center (Food Research Institute & Fermented Food Research Institute).
Thanks to research up to this point, the means of using prolonged heat to determine the sugar content in foods (pH levels, concentration, etc.) and detect the traces of rare sugar (D-allulose) has been well developed.