Traditionally, egg yolk has provided stabilization for oil and water emulsions, as well as a full body and unique taste. Nevertheless, demand for yolk-less sauces presents a challenge for the food industry, especially where products must tolerate long-term storage.
Emultop®, a de-oiled, enzymatically hydrolyzed lecithin obtained from vegetable oilseeds such as soybeans, can reduce the interfacial tension between oil and water, making it possible to achieve fine dispersions.
“De-oiled means it is in a powdered form and contains less than 5% oil,” explains Erin Chavez Surratt, senior application specialist at Degussa Texturant Systems (Atlanta). “This hydrolyzed lecithin offers more hydrophilic character, which provides better oil-in-water emulsions than standard lecithin products.”
“The most suitable lecithin for oil-in-water emulsions like dressings and mayonnaises is Emultop,” says Elke Schuster, an application development expert at Degussa.
Emulsifiers will have hydrophilic and lipophilic moieties on their molecule, where the lipophilic portion adsorbs onto the oil droplet and the hydrophilic end extends into the continuous or aqueous phase.
The emulsifier aligns itself around the oil droplets, creating a barrier to subsequent coalescence and destabilization. “However, these emulsifiers only provide short-term stability and, if used alone, the emulsion eventually will coalesce,” warns Chavez.
There are two phases for stabilization: short term-stabilization with an emulsifier like Emultop, and long-term stabilization by viscosifiers like the VitexTM KCT series, which utilizes blends of gums and emulsifiers.
The Vitex KCT range provides a viscous matrix that inhibits mobility of the oil particles and, therefore, prevents coalescence of the oil particle and subsequent destabilization of the emulsion.
“Degussa provides emulsifier/stabilizer blends containing emulsifying pectin, starch or PGA, along with viscosifiers such as xanthan, guar, carrageenan or locust bean gum,” notes Chavez.
Certain products within the Vitex KCT range are well-balanced combinations of differing hydrocolloids and a selection of the best suitable dairy proteins that provide emulsions with a smooth, creamy and short texture.
Vicosifiers ensure stable interfaces that withstand growing ice crystals during the freezing period, especially when temperature variations occur. Such ice crystals may lead to leakages in the interfaces and, as a consequence, unstable products.
The special synergies of hydrocolloids and dairy proteins at the required levels in the Vitex KCT series guarantee excellent emulsion stability, even when the products are thawed in the microwave. Tailor-made solutions are produced for every application.
Additionally, the blends for freeze/thaw-stable mayonnaises from the Vitex KCT series are easy to handle, can be used in vegetarian formulations, and are free of genetically modified organisms (GMOs), starch and cholesterol.
Degussa Food Ingredients has developed complete solutions for freeze/thaw stable emulsified sauces with oil contents up to 50%. The lower the oil content, the more weighted is the influence from the water phase and its texturizing ingredients. Therefore, a careful selection of hydrocolloids is necessary to ensure not only the required viscosity but also the desired structure.
Degussa Food Ingredients' Business Line Texturant Systems presents emulsifier and stabilizer concepts for all kinds of emulsified sauces.