” bg_image=”2973″][/vc_column][/vc_row][vc_row][vc_column][vc_empty_space][/vc_column][/vc_row][vc_row][vc_column width=”2/3″][vc_custom_heading text=”Lecithin Emulsifier and Beyond” font_container=”tag:h4|text_align:left” use_theme_fonts=”yes”][vc_column_text]
Lecithin is an emulsifying substance found in the cells of all living organisms. The French scientist Maurice Gobley discovered lecithin in 1846 and named it “lekithos” after the Greek word for “egg yolk.” Until it was recovered from the waste products of soybean processing in the 1930s, eggs were the primary source of commercial lecithin.
Today lecithin is the generic name given to a whole class of fat-and-water soluble compounds called phospholipids. Phospholipids are important biochemical intermediates in the growth and functioning of cells in plants and animals. Almost all body cells contain phospholipids.
Animal lecithin products are derived from milk, eggs and fish. Vegetable lecithins, containing primarily PC, PE and PI, and are derived commercially from oil-bearing seeds such as soybeans, sunflower kernels, rapeseed and rice bran.
Soybean is the main source of Lecithin and majority of Lecithin related products are produced from Soy Lecithin. Levels of phospholipids in soybean oils range from 1.48 to 3.08 percent, which is considerably higher than the 0.5 percent typically found in vegetable oils, but far less than the 30 percent found in egg yolks.
[/vc_column_text][/vc_column][vc_column width=”1/3″][vc_empty_space][vc_custom_heading text=”The typical soya lecithin composition is:” font_container=”tag:h6|text_align:left|color:%2381c94c” use_theme_fonts=”yes”][cs_icon_text icon_group=”%5B%7B%22icon%22%3A%22fas%20fa-angle-right%22%2C%22title%22%3A%22Phosphatidylcholine%20(PC)%22%7D%2C%7B%22icon%22%3A%22fas%20fa-angle-right%22%2C%22title%22%3A%22Phosphatidylethanolamine%20(PE)%22%7D%2C%7B%22icon%22%3A%22fas%20fa-angle-right%22%2C%22title%22%3A%22Phosphatydalinositol%20(PI)%22%7D%2C%7B%22icon%22%3A%22fas%20fa-angle-right%22%2C%22title%22%3A%22Other%20phosphatides%22%7D%2C%7B%22icon%22%3A%22fas%20fa-angle-right%22%2C%22title%22%3A%22Soy%20Oil%22%7D%5D”][vc_custom_heading text=”Lecithins also have characteristics that help:” font_container=”tag:h6|text_align:left|color:%2381c94c” use_theme_fonts=”yes”][cs_icon_text icon_group=”%5B%7B%22icon%22%3A%22fas%20fa-angle-right%22%2C%22title%22%3A%22Disperse%20and%20suspend%20powders%20into%20liquids.%22%7D%2C%7B%22icon%22%3A%22fas%20fa-angle-right%22%2C%22title%22%3A%22Control%20the%20viscosity%20of%20liquids%20and%20semi-liquids.%22%7D%2C%7B%22icon%22%3A%22fas%20fa-angle-right%22%2C%22title%22%3A%22Prevent%20foods%20from%20sticking%20to%20contact%20surfaces.%22%7D%2C%7B%22icon%22%3A%22fas%20fa-angle-right%22%2C%22title%22%3A%22Prevent%20adhesion%20of%20food%20products%20to%20one%20another.%22%7D%5D”][/vc_column][/vc_row][vc_row][vc_column width=”1/2″][vc_empty_space][vc_custom_heading text=”Lecithin has functional values as” font_container=”tag:h6|text_align:left|color:%2381c94c” use_theme_fonts=”yes”][vc_row_inner][vc_column_inner][vc_column_text]Emulsifiers:
Emulsions are produced by dispersing normally unmixable material into another by mixing, colloidal milling or homogenization. The surface-active qualities of lecithins make them effective emulsifying agents that reduce mixing time and maintain the stability of the dispersion.
Lecithins greatly reduce the surface tension of fats, enabling particles of chocolate, sugar and milk products, for example, to be coated, improving flow and mixability. Typical usage levels are 0.2 – 0.6% of total product weight.
Lecithins have nutritional value of their own. The phospholipids they contain, such as phosphatidylcholine (PC), phosphatidylserine (PS) and derivatives such as glycero- phosphocholine (alpha-GPC) have been widely acknowledged by nutritionists, and substantiated by numerous human clinical studies, as beneficial to the function of the liver, brain, heart, and other organs.
The phospholipids are insoluble in acetone and thus acetone allows an extraction of about 40 % vegetable oil of the crude lecithin. The de-oiled lecithin is obtained after evaporation of the acetone. The extraction can either be a batch or a continuous process. Deoiled lecithin has several advantages; the powder has convenient handling, it has a more neutral taste since the unsaturated fatty acids of vegetable oil has been removed; deoiled lecithin is more hydrophilic than standard lecithin.
The method involves principles of enzymatic hydrolysis of phospholipids. Food grade enzymes are used that allow selective hydrolysis of the fatty acids. The process conditions determine the extent of the hydrolysis as well as the relative hydrolysis of the different kinds of phospholipids. From an application point of view it is important to differentiate between low, medium and high “degree of hydrolysis”. Hydrolyzed lecithin has several advantages; it is more hydrophilic depending on the degree of hydrolysis and this allows the use of lecithins in cream emulsion types as well as in frying margarines. It’s monoglyceride like structure with only one fatty acid is much more effective in bakery products for softness and longer shelf life.
Phosphatidylcholine (PC) is relatively more soluble in ethanol than all other phospholipids. This allows a semi quantitative fractionation of PC which can be decanted from a “bottom fraction” with relatively less PC, the so called PE-fraction or PC depleted fraction. It is possible to obtain PC contents in the range of 30-50 % by this process. More pure PC fractions can be produced by using column chromatography with adsorbents. On commercial plant scale, oil-free lecithin or its ethanol-soluble PC fraction is treated in a chromatographic column with aluminum oxide adsorbent, on which the non-PC phospholipids are absorbed. The PC is concentrated at 70–95% purity. Higher percentages of PC fractions are very difficult to handle in practice unless sprayed on a carrier. Fractionated lecithin has several advantages; The PC-fraction is choline enriched for dietary purposes, it has its own characteristic hydrophilicity and emulsification properties, it is less sensitive to calcium in hard water, it is less sensitive to browning on extended heating. The PE fraction finds special uses in emulsification and baking applications
These types of lecithins are not permitted for foods in Europe, they are allowed for foods in North America. Hydroxylation of the unsaturated fatty acids of the phospholipids is made in the presence of peroxide and organic acids resulting in the highest possible lecithin hydrophilicity. Hydroxylated lecithin is superior for emulsification of cakes and cookies, but can only be used in North America. Acetylation of the amino group in phosphatidylethanolamine is achieved by reaction with acetic anhydride resulting in better resistance to browning on heating as well as in different functional properties. Acetylated lecithin finds use in Europe for “leather tanning”.
