Liquid glucose is a solution of glucose suspended in liquid and sold in jars or tubs. Many companies manufacture glucose in powdered form to which water can be added to make liquid glucose, to make transportation of this product easier. This product is available from a variety of sources, depending on how one intends to use it. Medical suppliers sometimes carry it, as do some grocery stores, especially stores with a large baking section.
This monosaccharide is produced through the processing of starches such as corn and wheat. Glucose has a famously strong sugar flavor, and it plays an important role in the human body in addition to being very useful in the kitchen. Liquid glucose is an extremely pure form of glucose which has a concentrated flavor. The strength means that people must use it carefully, as it is easy to dispense too much for a particular application.
In cooking, liquid glucose is used as a sweetener in a range of foods. This product does not crystallize, sweetens evenly, helps to preserve food, and has a very low freezing point, making it appealing for things like candy and ice cream. European recipes tend to call for this ingredient more commonly, and it is more readily available in European stores for this reason. Corn syrup is similar in nature, and can be used as a replacement if liquid glucose is not available, although the recipe may come out slightly differently due to natural variations.
In medicine, liquid glucose is used when a patient has dangerously low blood sugar and a care provider wants to get blood sugar levels raised as quickly as possible. It can be administered by mouth or by injection to raise blood sugar levels. The problem of low blood sugar is most commonly seen in diabetic patients who have entered a hypoglycemic state. Diabetics are usually attentive about monitoring their blood glucose levels and adjusting their medications or sugar intake as needed to prevent complications such as hypoglycemia, but sometimes they are caught unawares.
Liquid glucose sold for medical use is often packaged in sterile containers. It is usually clear, and highly viscous. Some companies manufacture single use packages which can be used to quickly dispense glucose to a patient, while others may sell larger bottles, with people dispensing the amount as needed. Small packages may be included in first aid kits carried on ambulances and by first responders so that they can intervene quickly in a situation where someone has become hypoglycemic.