The aim of this work is to study the influence of the lecithin addition in the margarine manufacturing process. The margarine is a stable emulsion based on vegetal fats and water; this product has plasticity, consistency, color, taste and flavor resembling with butter [1]. For the qualitative study of the finished product, the acidity index, saponification index and acetylation index have been determined. These indexes are important due the fact that their value directly influences the stability of the product.
