The outside of the bottle should be cleaned of drips after each use. Some pure cane and sorghum syrups may crystallize in storage, but this causes no harm and they can be reliquified using the same method as for honey. Corn Syrup Corn syrup is a liquid sweetener made by an enzyme reaction with corn starch. Both types often contain flavorings and preservatives. They are commonly used in baking and candy making because they do not crystallize when heated.
Corn syrup is very common in the U.S., but less so in the rest of the world.
It should be stored in its original bottle, tightly capped, in a cool, dry place. New unopened bottles keep about six months from the date on the label. After opening, keep the corn syrup four to six months. These syrups are very prone to mold and to fermentation so be on the lookout for bubbling or a mold haze. If these present themselves, throw the syrup out.