Polyglycerols are intermolecular ethers of glycerol formed by condensation of “n” (2 or more) glycerol molecules with elimination of “n-1” water molecules. Spiga Nord S.p.A. produces such substances exclusively by polycondesation of refined glycerine of vegetable origin GMO free, kosher, Halal and E422 compliant.

Thanks to the special technology developed, Spiga Nord is able to obtain finished products characterized by a high content of linear polymers and reduced content of cyclic compounds. Such technology elaborated entirely thanks to in-house know-how and the company’s fifty years of experience in glycerine refining has made it possible to obtain products whose qualitative characteristics are unmatched on the market: products with a pleasant taste and no odor, characterized by high color standards – Polyglycerol-3 and Polyglycerol-4 have a typical value < 50 hazen, 3 times lower than market values – characterized by remarkable thermal stability. Due to these properties, they particularly find application in sectors, such as food and cosmetics, where it is essential to avoid degradation phenomena of the product’s original characteristics.

Spiga Nord’s polyglycerols can be used for the production of esters in line with the specifications outlined in European Regulation 2023/1329 for food additives E475 POLYGLYCEROL ESTERS OF FATTY ACIDS and E476 POLYGLYCEROL POLYRICINOLEATE as well as the specifications imposed by 21 CFR 172.854 for thefood additive POLYGLYCEROL ESTERS OF FATTY ACIDS. Polyglycerol esters have several functions within food products: emulsifiers, fat substitutes, and aids in maintaining the rheological characteristics of the food.

Due to their vegetable origin, they can be used in 100% natural final formulations; this feature is particularly attractive for cosmetic applications where the use of ethoxylated derivatives is increasingly questioned for dermatological and environmental reasons: polyglycerol esters allow the preparation of emulsions free of ethoxylated compounds.

Polyglycerols can be successfully used in cosmetic formulations as solvents for fragrances due to their nonvolatile nature or as skin moisturizers because, due to a lower content of hydroxyl groups within the molecule and higher molecular weight than glycerol, polyglycerols and, consequently, polyglycerol esters (PGE), are well tolerated by the skin. In the research and development stages of cosmetic products, it is absolutely essential to ensure the stability and functionality of the product throughout its shelf-life; in particular, cosmetic products must maintain their texture, fragrance, softness, and rapid absorption during use: polyglycerol esters, together with other components, enable both goals to be achieved. They can be used as nonionic emulsifiers, dispersants, emollients, wetting agents or thickeners in personal care formulations.

Another interesting feature of this family of products is versatility: in fact, one or more of the hydroxyl groups in the molecule can be esterified with an acid of the same or other type to obtain a wide variety of emulsifiers or surfactants characterized by specific HLB values (Hydrophilic-lipophilic balance).

Because of the properties described, polyglycerols can also be used in various technical applications.

Polyglycerol and, more often, its ester is used for Polymers: as a plasticizer, to provide new specific rheological characteristics to the product, added directly during bulk polymerization, in suspension, or in the final stages of production; as an anti-fog agent capable of migrating to the polymer surface, but not outside the product itself; and as a lubricant due to high viscosity even at high temperatures.