What is Lecithin?

Lecithin is derived from the Greek word for egg yolk (lekithos), with a high amount of lecithin in the egg yolk. Naturally, lecithin-rich foods have a high fat content; like eggs, beef liver. But peanuts, beef, some fruits and vegetables contain less lecithin.

The E codes (EC Code) are the code numbers for each food additive set by the European Union.Food additives are used in the definition of all kinds of food in order to ensure integrity throughout the world. Each food item has an E code. The letter E stands for “Europe”.

E322 Lecithin is an emulsion obtained from soybean, egg yolk, peanut, corn or animal sources. Emulsifiers prevent oil from separating from the water phase. . It is not toxic but overdose disrupts the stomach, cuts the appetite and causes sweating. margarine, chocolate, mayonnaise and milk powder is used to provide the composition of oils. Herbal type should be preferred.

Lecithin is also called phosphatidylcholine. Lecithin is produced as a by-product during the production of flour from soybean sprouts or during the production of soybean oil from soybean plants and contains glaucolipids, triglycerides and phospholipids. Phospholipids are the building blocks in the cell membrane that all cells in the body need. Phospholipids prevent cell membrane hardening. Lecithin protects cells against oxidation and acts as the protective membrane surrounding the brain in humans.

Lecithin is also sold in the form of soft gelatin capsules or granular powders and is consumed for various health reasons because it is believed to lower cholesterol, strengthen memory, improve liver function among the population. The effect of lecithin in lowering cholesterol in humans was investigated. However, in a review published in the American Journal of Clinical Nutrition in 1989, examining the results of 24 studies, there was little evidence that lecithin directly reduces cholesterol (Knuiman et al., 1989).

There are also studies on the effects of lecithin on memory functions. There is no certainty that lecithin improves memory, because inconsistencies have been observed in human studies. Other potential benefits of lecithin are its role in liver and reproductive health, as well as in improving physical performance in certain activities. Further research is needed to confirm these health effects of lecithin.

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Great information.
Lecithin or phosphatidylcholine is composed of the backbone glycerol structure, along with 2 fatty acids, phosphoric acid and a nitrogen containing compound. Due to these groups present in it, it is both hydrophilic and lipophilic. And thus an emulsifier too.
Lecithin is not 100% PC but contains phosphatidylserine, phosphatidylethanolamine etc.
Commonly used as an emulsifier, while it is also utilized as a viscosity modifier, wetting agent, release agent etc. Its applications has extended to several kinds of food - especially milk based products, icecream industry etc. In the U.S, soy lecithins are approved as GRAS. We can expect more out of lecithin research in the future!

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What is the degradation temperature of lecithin? On which temperature it loss it’s emulsifying properties

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Thanks for moving a step further towards the learning on lecithin. Exact degrdation temp could be difficult aspect since it contains a mixture of molecules. Some details that might be relevant to your query:::
Lecithin is composed of various phospholipids (PLs), abundant being phosphatidylcholine (PC) and phosphatidylethanolamine (PE). soybean lecithin is prone to oxidation, sensitive to heat and light, which restricts its application in industries. As known from its structure, the fatty acid composition of lecithin affect/ determines the stability. Some details shows that phospholipids remain unchanged at temperatures up to 100°C, though color changes are known. If triglycerides and PLs are removed, a huge difference in aroma might occur, and probably structural phospholipids are essential for specific aroma.
As per literature, Lecithin is useful for enhancing the heat stability of emulsions, due to interactions between lecithin and proteins. How about using materials like CD (Cyclodextrin) to enhance the stability, by forming an inclusion complex.

Creaming stability might be a way to assess the thermodynamic stability of emulsion prepared. Not to forget the concentration of lecithin, pH, other gums (gellan, gum Arabic) etc are all factors to be considered when expanding this research. In many cases, lecithin is used along with milk or other major constituents, where the interactions of proteins with lecithin help to stabilize the preparation.In the food industry, emulsifiers are usually used with other thickeners, such as xanthan gum, to give better emulsion stability.
A good reference to check on emulsion would be chapter 6 from Food Emulsifiers & their applications book by Hasenhuettl et al.

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Great answer. thank you @nanoscientist