Inulin, a dietary fibre found in a wide variety of fruits, vegetables, and herbs, can be used as a fat replacer in bakery products without affecting their taste and functionality, according to a new study conducted by researchers at University Politècnica de València, Spain.
Since fat has the highest energetic value compared to all major food constituents, replacing it with a dietary fibre can cut down the fat levels in food by up to 70%, which will help manufacturers in offering healthier food products, the study published in the Journal of Food Science has revealed.
For the study, the research team, led by Julia Rodríguez-García, evaluated the effects and physicochemical properties of a sponge cake after replacing the fat with inulin at various levels - 0%, 35%, 50%, 70%, and 100%.
It was found that fat substitution significantly lowered batter viscosity, leading to heterogeneous bubbles size distributions.
Rodríguez-García said that the absence of oil - which acts as an interface, stabilizing air bubbles - gave place to a less aerated structure after baking.
The rest of the fat was found to be located at the bubbles' interface, resulting in optimum cake structure development during baking.
"Cakes with fat replacement up to 70% had a high crumb air cell values; they were softer and rated as acceptable by an untrained sensory panel," said Rodríguez-García.
The team concluded that a quality cake can be made with 70% of oil replacement, and can be labelled as 'reduced in fat' as per the US and EU regulations.
Inulin is increasingly used in processed foods because of its adaptable characteristics, and has been used to replace fat in meat and dairy products.
