Introduction
Flavors are generally divided into natural flavors and artificial flavors, of which natural flavors are widely used, but natural flavors have low bioavailability, poor absorption, rapid metabolism, poor stability, easy oxidation, irritability, and other problems. In general, such problems can be solved by microencapsulation of flavors. Such microencapsulation is usually accomplished using water-soluble polymers co-adsorbed or using complexes formed from β-cyclodextrins. In recent years, encapsulation of fragrances and other aromatic agents with liposomes has gradually shown great advantages.

Advantages
Liposomes are amphiphilic, so liposome microencapsulated flavors are in contact with water and remain encapsulated, and the dissolution of aggregates in water does not occur, while fat-soluble flavors are suspended in water.
After the liposome is encapsulated, the solubility of insoluble fragrance can be increased, the bioavailability of water-soluble fragrance can be improved, the stability of natural fragrance containing active group can be improved, and the irritability can be reduced.

Liposome-encapsulated Flavors in Food
In cheese manufacturing, adding flavors directly to the milk results in the loss of flavor in the whey during curd formation, a process that can be avoided with liposome encapsulation. Flavors encapsulated in liposomes remain mostly in the matrix during protein coagulation, which results in a more flavorful finished cheese than a cheese without flavors. In addition, the presence of liposomes could be observed after several days of product retention, indicating a longer release time of the encapsulated spices and a longer duration of cheese flavor.

In addition, the preparation of liposomal microencapsulated flavors by steaming and extrusion can be applied to the production of cookies to improve the long-lasting flavor of the product during processing and preservation. Liposome encapsulation can promote the dissolution of flavors in the lipid or aqueous phase of the cookies, resulting in a better flavor of the product. Surface modifications of liposomes, such as the preparation of temperature-sensitive liposomes, can allow flavor to be released only in the mouth or break down the liposomes when heated, thus releasing fresh flavor similar to that of a freshly baked cookie.

Liposome-encapsulated Fragrances in Toiletries
Toiletries also usually include a lot of fragrance and flavoring. However, fragrances evaporate quickly and do not last long, and the fragrance itself may cause irritating skin sensitization. By liposome encapsulation, the solubility of essential oils/fragrances in water is improved, their active substances are protected from destruction by enzymes and the immune system during transport, and their stability is improved, while having a slow-release effect that prolongs the action of the fragrance-period encapsulated substances and improves their bioavailability.

Examples of available formulations are as follows.
A fragrance slow-release liposome made from the following mass percentages of raw materials: lecithin 5-10%, hydroxylated lecithin 1-5%, cholesterol 3-7%, glycerol poly-4-oleate 5-10%, propylene glycol octanoate/isopropylene glycol ester 5 -10 10%, fragrance 1-5%, glycerol 1-5%, butylene glycol 1-5%, and water 50-80%.

Mix lecithin, hydroxylated lecithin, cholesterol, polyglyceryl 4 oleate, propylene glycol octanoate/isopropylene glycol and fragrance to make the oil phase; add ethanol and heat and stir until completely dissolved.
Vacuum rotary evaporation to remove ethanol and form a uniform oil film on the wall of the bottle; add an aqueous solution containing butylene glycol and glycerol and continue to rotate until the oil film is completely dispersed in water to obtain a suspension.

Pour the suspension into a high-pressure homogenizer for high-pressure homogenization to obtain liposomes.

About Us
BOC Sciences' liposome platform provides you with the best compound 23 (BETd-260/ZBC260). We can prepare liposomes by selecting specific phospholipids and technologies based on cargo or release conditions.