Egg yolk lecithin powder is from egg yolk. The lecithin accounts for about 10% of the total weight of egg yolk. Its composition is mainly phosphatidylcholine, which makes egg yolk lecithin have unique advantages in nutrition and health care and certain high-end foods, cosmetics, and other fields. The fatty acid composition of bulk egg yolk lecithin is relatively complex, including saturated fatty acids and unsaturated fatty acids. Among them, unsaturated fatty acids such as oleic acid are beneficial to human health.
Egg Yolk Lecithin Flow Chart:
Guanjie Biotech is an egg yolk lecithin powder manufacturer. We use organic solvent extraction to extract egg yolk lecithin. We provide waxy lecithin 80-98.
Extraction principle:
Use the solubility of lecithin in organic solvents. Lecithin has a high solubility in organic solvents such as ethanol, while some impurities in egg yolk (such as protein, cholesterol, etc.) have relatively low solubility in these solvents. Through this difference in solubility, lecithin is extracted from the egg yolk.
For example, in an ethanol-water system, lecithin can be well dissolved in the ethanol phase. However, impurities such as proteins have limited solubility in ethanol and can be separated from lecithin by precipitation and other methods under appropriate conditions.
Specific steps:
1. Raw material pretreatment:
First, break the egg and carefully separate the yolk. This can be done by simple manual operation or using special egg separation equipment. During the separation process, try to avoid mixing egg white with egg yolk. Because the components in egg white may interfere with the subsequent extraction process.
After obtaining the pure egg yolk, dilute the egg yolk with an appropriate amount of water or buffer solution. The purpose of dilution is to reduce the viscosity of the egg yolk and make the subsequent extraction process easier. Generally speaking, the volume ratio of egg yolk to diluent can be controlled at about 1:1 - 1:3.
2. Extraction process:
Transfer the diluted egg yolk lecithin liquid to a suitable extraction container (such as a three-necked flask) and add an organic solvent. The commonly used organic solvent is ethanol, and the concentration of ethanol generally used is 90% - 95%. The volume ratio of egg yolk liquid to ethanol is usually around 1:4 - 1:5.
During the extraction process, the temperature and stirring speed need to be controlled. The temperature is generally maintained at 30 - 40℃, which helps the dissolution of lecithin in ethanol without causing excessive denaturation of other components in the egg yolk. The stirring speed can be controlled at 100 - 200 rpm. This allows the egg yolk liquid and ethanol to be fully mixed and accelerates the dissolution of lecithin. The extraction time is generally 2 - 3 hours to ensure that the bulk egg yolk lecithin is fully dissolved in ethanol.
3. Separation operation:
After the extraction is completed, the ethanol extract containing lecithin needs to be separated from the egg yolk residue. The mixed solution can be transferred to a centrifuge tube by centrifugation and centrifuged at 3000 - 5000 rpm for 10 - 15 minutes in a centrifuge. After centrifugation, the supernatant is an ethanol extract containing lecithin, and the lower layer is the egg yolk residue.
It can also be separated by filtration. For example, filter paper or filter membrane (pore size 0.45 - 0.8μm) is used for filtration. Slowly pour the extract into the filter, let the liquid pass through the filter paper or filter membrane, and the egg yolk residue remains on the filter to obtain a clear ethanol extract containing lecithin.
4. Concentration step:
The separated ethanol extract is concentrated under reduced pressure. The extract is transferred to the flask of the rotary evaporator, and the ethanol is evaporated by the rotary evaporator under reduced pressure (pressure is generally 5-10kPa) and temperature is controlled at 40-50℃. In this process, ethanol gradually evaporates and lecithin is concentrated in the flask. This forms crude lecithin.
5. Refining process:
To obtain high-purity bulk egg yolk lecithin, column chromatography can be used for refining. Taking the silica gel column as an example, silica gel is filled into the chromatographic column and chloroform-methanol-water (65:25:4) is used as eluent. The crude lecithin is dissolved in a small amount of eluent and then loaded onto the top of the silica gel column.
The eluent is eluted at an appropriate flow rate (such as 1-2mL/min). During the elution process, different components are gradually separated in the silica gel column according to their adsorption-desorption characteristics with silica gel and their solubility differences in the eluent. By detecting the eluent (such as using thin-layer chromatography), the eluent part containing lecithin is collected. Finally, the collected eluent is evaporated under reduced pressure to obtain refined lecithin.
Technical advantages:
• Relatively high extraction efficiency
Organic solvents have good solubility for lecithin in egg yolk. Lecithin in egg yolk belongs to lipid substances and can be well soluble in organic solvents such as ethanol, acetone, chloroform-methanol mixture, etc. For example, chloroform-methanol (2:1, v/v) mixed solvent is widely used for lipid extraction. This solvent system can effectively separate lecithin from the complex components of egg yolk. Compared with some traditional extraction methods, it can obtain a higher extraction rate in a shorter time.
• Better selectivity
Selective extraction of lecithin can be achieved by selecting a suitable organic solvent. Different organic solvents have different affinities for different lipid components. For example, ethanol has a good selective solubility for lecithin during the extraction process. However, it has a relatively weak solubility for some impurities such as proteins and sugars in egg yolk. In this way, the dissolution of impurities can be reduced during the extraction process, making the purity of the extracted lecithin relatively high.
• Relatively mature and simple process
Organic solvent extraction is a classic extraction method. From laboratory trials to large-scale industrial production, there are relatively mature process flows. Its operating steps are relatively easy to understand and master. This mainly includes steps such as egg yolk pretreatment (such as dilution, homogenization, etc.), organic solvent extraction, separation (such as centrifugation or separation funnel separation), and solvent evaporation. For example, in the laboratory, a simple separatory funnel can be used to separate the organic phase and the aqueous phase after extraction. This can obtain an organic phase containing lecithin, which is convenient for subsequent processing.
• The quality of the extracted product is good
Lecithin extracted by organic solvent can be well maintained in structure and performance. Because this extraction method is relatively mild, under appropriate operating conditions (such as appropriate temperature, solvent concentration, etc.), excessive oxidation, hydrolysis, and other chemical reactions of lecithin can be avoided. Therefore, the extracted lecithin can reach a high level in terms of the content and activity of effective ingredients such as phosphatidylcholine. It can be widely used in food, medicine, cosmetics and other industries.
Where To Buy Egg Yolk Lecithin?
If you need to add bulk egg yolk lecithin to your product, please contact us at info@gybiotech.com. We have been focusing on the research and development, production, testing, and sales of egg yolk lecithin for more than 20 years. The technology is mature. We can also provide free samples for your testing.
