Danish scientists prepare skimmed whipped cream from lactic acid bacteria
The human love affair with whipped cream dates back to at least the 16th century and is a staple of all our favorite holiday desserts. Is that slice of Thanksgiving pumpkin pie really the same without a dollop of whipped cream on top? But whipped cream also contains 38 percent saturated fat. That’s one of the reasons it’s so delightfully fluffy and nice to eat, but it’s also not great for our health, and dairy production is a major source of greenhouse gases. So food scientists from the University of Copenhagen decided to investigate possible sustainable, low-fat alternatives. They successfully created a bacteria-based fat-free prototype, according to a recent paper published in the journal Food Hydrocolloids. Someday, the authors say, the whipped topping on our holiday desserts could be made from leftover beer or plants.
“We usually associate bacteria with something to keep away from food,” said co-author Jens Risbo, a food scientist at the University of Copenhagen. “But here we base a favorite food product on good bacteria found in nature. This has never been seen before. It’s an advantage, both because it’s a renewable, tank-grown resource, and because it creates a healthier, less energy-dense, fat-free product.”
Whipped cream is a type of liquid mousse, a category that also includes hair mousse and shaving cream. Such foams are created by whipping air into a liquid formula that contains, among other ingredients, some type of surfactant (surfactant) – a collection of complex molecules that bind together to solidify the resulting foam into a substantial foam. Surfactant—usually fats or proteins in edible foams or chemical additives in shaving cream or styling foam—keeps surface tension from collapsing bubbles by strengthening the thin liquid film walls that separate them. Cream, with its high fat content, serves as a surfactant in whipped cream.
In 1948, a clothing salesman-turned-entrepreneur named Aaron (“Bunny”) Lapin figured out how to ship whipped cream from a can and introduced the world to Reddi-Wip. The gas is mixed with the liquid formula and packaged under pressure in the aerosol can. When the valve is opened, the mixture is forced out of the box by nitrous oxide (suspended gas) and the gas expands rapidly to create foam. In the non-dairy varieties of Reddi-Wip, the cream is replaced with vegetable oil, which has an even higher fat content, along with an array of synthetic additives (polysorbate 60, sorbitan monostearates, sodium stearoyl-2, lactylate, xanthan gum, and lecithin). .
It’s not easy to come up with a tasty yet healthy alternative to one of our favorite treats. “The most difficult aspect of developing an alternative food is getting the texture right,” said Drawing. “Whipped cream undergoes a unique transformation that occurs in a complex system where the high content of saturated fat makes it possible for the cream to become hard. So how do we create an alternative that avoids the high fat content while achieving the right consistency? We have to think innovatively here.”
Risbaugh and his colleagues used just four ingredients in their experiments: water, edible lactic acid bacteria, some milk protein, and a thickener. There are many types of lactic acid bacteria – the types used by the food industry as culture for yogurt and to preserve cold cuts – and they are abundant in nature, found in plants and in human/animal mucus membranes and digestive tracts. They also happen to be ideal building blocks for foods and are about the same size as the fat globules in heavy whipping cream.
The Danish team made both soft and firmer versions of their prototype whipped cream using two different strains of bacteria: Lactobacillus delbrueckii subs. from the milk (LBD) and Lactobacillus curlatus (LBC). The LBC strain is more hydrophobic, producing a cream that is firmer and holds liquid better than the mixture produced with LBD, which is hydrophilic.
These experiments were primarily to demonstrate proof of concept and the resulting foams were evaluated primarily for texture and desired foaming characteristics – not for taste. So we’re unlikely to see boxes of “Lacti-Wip” on store shelves anytime soon. But the experiments provided valuable insight into how best to create a dairy-free whipped cream alternative with a similar food structure.
“We have shown that bacteria can be used to create the correct structure,” said Drawing. “Now that we understand the context and have learned which surface properties are important, it opens up the possibility of using many other things from nature. This could be leftover yeast from the brewery, or perhaps small building blocks that we extract from plants. This would make the product very sustainable.”