Trehalose, like Maltose, is 45% as sweet as sugar. It occurs natuarlly in a few succulent plants, some mushrooms and in brewers yeast. However, the amounts are very small and are not sufficient to have any noticeable effect when consumed by people. Trehalose is made from corn or tappioca starch by using enzymes to convert the starch to glucose firstly and then to Trehalose.
It is safe to eat in quite large quantities (60g in one serving) and does not lead to a rise in blood glucose levels. It has a negligible effect on blood glucose levels when consumed. For this reason it is not only safe for diabetics to consume it may have some benefits. One of the features of Trehalose is that it appears to protect nervous system tissue and reduce/prevent protein malfolding.
Protein malfolding is at the heart of virtually every illness and central to Alzheimers and Parkinsons diseases. Trehalose actually prevents good proteins from malfolding and consequently may be of help.
Trehalose was first used in Japanese food and sushi in particular. It helps stabilise the rice, improve shelf life and even improve natural flavours. We use it in baking where it can be substitued for caster sugar in most recipes. It does not brown like sugar, and has very low hygroscopicity (moisture attraction), so it stays free flowing and dry. It works well as a protein stabilization addition (beverage, surimi, sushi). Trehalose is also used in foods as a sweetener, a stabilizer and thickener, and a flavour enhancer. It is also used as a cryopreservation additive, where it protects cells from the effects of freezing and drying.