Glycerol is a component of triglycerides, found in fats and oils. In soap - making (saponification), triglycerides react with alkalis, splitting into soap and glycerol.

In biodiesel production, when vegetable oils or animal fats react with alcohol, glycerol is produced as a by - product. The growth of the biodiesel industry has made this a major source of glycerol.

In the body, glycerol is released during the breakdown of body fat for energy. Some microbes, like yeast during fermentation, also produce glycerol.

Glycerol keeps baked goods moist, extending their shelf - life. It stops bread, cakes, and cookies from drying out.

With a sweet taste and fewer calories than sugar, it's used in low - calorie and sugar - free foods, like chewing gum, where it also maintains texture.

It helps blend oil and water in products like salad dressings and some dairy items.

Glycerol helps dissolve active ingredients in liquid meds, like cough syrups, and gives them a smooth texture.

In suppositories and enemas, its lubricating property eases insertion.

It's in wound - healing products, keeping wounds moist to speed up healing and reduce scarring.

As a humectant in moisturizers, it draws moisture to the skin, preventing dryness and aging.

In shampoos and conditioners, it smooths hair, reduces frizz, and keeps hair moisturized.

In toothpaste, it provides a smooth consistency, and in soaps, it makes them more moisturizing.

It's used in engines and machinery as a coolant and lubricant, protecting parts from wear.

Glycerol improves the flexibility and durability of plastics, like in polyurethane production.

It can be converted into nitroglycerin, a key explosive component, though often absorbed onto a safe material.