Why is there a sugar content in some powdered Spirulina products?

During the processing (spray drying, etc.) companies add maltodextrin which is a synthetic sugar to their products. (be sure to check the labels).  They do this as a filler and to mask the bad taste powders have with a sweetener.

Maltodextrin has a glycemic index ranging from 85 to 105. It should never be consumed.

Also, during the heating – cooking the lipids (fats) is converted to sugar.