What is Lecithin?
Lecithin is a natural emulsifier and stabilizer in foods. It's widely used in cakes and yeast-leavened bakery products. This ingredient is found in raw materials such as eggs or soybeans, and can be used as a clean label ingredient.
It is used as a:
- Wetting agent
- Pan release agent
- Cake batter stabilizer
- Fat replacer
Lecithin is a key component of cell membranes, and found frequently in nature. For example, it's in plant sources such as soybeans, corn and rapeseed. Also, it's found in animal products such as egg yolks.
It was discovered in 1846 by the French chemist Maurice Gobley. He isolated an orange-colored substance from egg yolk and called lecithin after the Greek name for egg yolk, “lekithos.”3 Egg yolk contains 10–20% lecithin, while most vegetable oils contain 0.1–3.0%.2
Chemically, lecithin is a glycerol with two fatty acid chains at carbons 1 and 2. Also, there is a phosphate ester group at the 3 position, which is bound to a molecule of choline. The phosphate and choline groups form phosphatidylcholine. This means the polar headgroup is the water loving part of lecithin.6 Meanwhile, fatty acid chains form the lipophilic region. These moieties make it an emulsifier.1,2
Lecithin’s hydrophilic-lipophilic balance (HLB) is intermediate and ranges from:7
- 3-4 for native fluid lecithin
- 7-8 for de-oiled lecithin
- 8- >10 for modified lecithin
This balance allows it to stabilize oil and water or water and oil emulsions and air bubbles in batters and creams. It also allows it to act as an effective wetting agent.2
Lecithin is produced commercially as a by-product of crude oilseed refining. It is a part of the “gum” that is removed during the degumming step of sunflower and rapeseed oil refining. To create different commercial products, bleaching with hydrogen peroxide, hot drying and chemical modifications are used.2
It is available as a powder or in liquid forms.
Lecithin is used in baked goods, confections, chocolate, cocoa powder, dairy products, icings, frostings, margarine and other spreads. It is usually added to bread formulations at 0.2% and to layer cakes at 0.5–1.5%, based on flour weight. It is also used in cake donut dry mixes at...