I have not managed to find any data in the literature, only this sentence in "Fats and Oils: Formulating and Processing for Applications, Third Edition by Richard D. O'Brien": "Lecithin is quite heat sensitive and can darken, smoke, and develop an offensive fishy odor and flavor at temperatures above 120°F (49°C)".

But the qualification of "quite heat sensitive" is not very precise...

I have never done any literature search on this but I know that we put it in many dairy product which has to pass thermal process like pasteurisation. However, the pasteurisation is usually by plate-heat exchanging and it is only few second. So, I think lecithin can survive at that conditions.

Thank you for these informations. So, do you think that lecithin is stable during treatment at 121°C 20 min? Even if, this treatment is repeated 2 times?

You can read the English abstract of Article Heat Deterioration of Phospholipids. II. Isolation and Ident...

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