Mimicking fat to improve flavour

Does anyone really enjoy eating low-fat dairy? Generally, we tend to eat low-fat dairy products for their purported health benefits, rather than for the taste.

However, new research from South Dakota State University (SDSU) could help improve the palatability of low-fat products with the use of a strain of lactic acid bacteria that mimics fat.

Extra body, less fat

Ashraf Hassan, associate professor of Dairy Science at the university, says some bacteria produce polysaccharides which can contain hundreds of sugar molecules, such as glucose, attached to one another. They bind significant amounts of water.

The strain Hassan has discovered produces polysaccharides with high water-binding capacity that then improve the quality of low-fat dairy products. “They give the same mouthfeel [as fat] by increasing the thickness and giving smoothness,” he said.

Hassan’s first experiment with the bacteria was to make low-fat cheese. It was so successful that a nationally recognised SDSU dairy products judging team couldn’t tell it apart from traditionally produced high-fat cheese.

SDSU dairy science associate professor Ashraf Hassan with doctoral student Nuria Garcia.

Pump up the protein

But the bacteria doesn’t only improve mouthfeel. The polysaccharide produced by this strain also improves the functionality of proteins recovered from the whey, Hassan says. This protein-polysaccharide mixture can be dried and added to salad dressings, mayonnaise and even processed meats. It has gelling properties that will create products that firm quickly and have a much stronger body.

This not only adds value to the whey; it also reduces manufacturing costs. When mixed with polysaccharide, less protein is needed to give the same effect.

In addition, the polysaccharide produced by this strain minimises the negative impact of heat on milk protein during pasteurisation, Hassan says. While heat denatures protein, the bacteria encapsulate the protein, maintaining its nutritional value.

Banishing biofilms

It seems there’s no end to what this bacteria can do. It will also address a major problem in the dairy industry: biofilms that form on milk processing equipment. Milk bacteria attach to contact surfaces and form colonies that can resist traditional cleaning methods. Hassan’s bacteria interferes with the formation of these biofilms, possibly mitigating this problem.

Hassan thinks this might also translate into better dental hygiene for consumers. He suspects that eating yoghurt made with these bacteria could help reduce plaque and prevent tooth decay.

To explore this possibility, Hassan is collaborating with a researcher from the University of Iowa’s School of Dentistry to secure funding from the National Institutes of Health.