19 August 2013

Food science that fools hunger pangs

Stomach
Feeling full for longer to satisfy appetites and help reduce snacking between meals is one of the solutions to reducing the amount of food we eat. Chemical engineers may have the answer as they develop special ingredients that have the potential to reduce hunger pangs once inside the stomach.

High fibre and protein rich diets are generally recognised for their ability to control hunger. However, modern food consumption has drifted towards softer textured foods, which are often high in fat and sugars.

The result is energy-rich, easily digestible foods that are unable to create a sense of feeling full and satisfied. It’s one of the factors contributing to rising obesity rates and an estimated 1.4 billion people being classed as overweight1.

One solution is to design foods that alter its structure once inside the body. The process can help control the rate of food digestion and also trick the body’s sensory systems, especially in the digestive tract, to make you feel fuller for longer.

One of the most interesting developments in the field is the creation of ‘gels’ that form once inside the stomach. It’s a technically difficult area where control of the gel’s bulk, strength and longevity are affected by the unique pH environment found in the stomach.

However, an important step forward has been made by a research team of chemical engineers at the University of Birmingham in the UK, who have been able to improve the control of gel formation inside the stomach.

Their research, to be published in Food Hydrocolloids2, used gellan gum – an existing food ingredient found in products such as sweets, soft drinks and soya milk. They found that by altering the chemical structure of the gellan gum they could change the properties of the gels, including important factors like its bulk, brittleness and texture.

David Brown, chief executive of the Institution of Chemical Engineers (IChemE), said: “Despite being a part of everyday life the science of managing appetites is a complex interaction of several factors and is not yet fully understood. However, the sensory signals from food, the digestive tract and the body’s energy reserves are all likely components affecting the desire to eat.

“Self-structuring gels like those researched by chemical engineers in Birmingham have a potentially important role in the future if we are to manage energy intake and address issues like obesity.

“Some theories suggest that the bulk created by the gels distend the stomach altering the sensory signals, as well as the size and structure of food as it enters the intestines. This is likely to extend the time taken to digest the food and may help to reduce snacking.

“Hopefully, this latest development by chemical engineers will help us to take another step forward to change lifestyles and improve the health and wellbeing of millions of people struggling to maintain a balanced diet.”

The role of chemical engineers in the food sector is explored in IChemE’s latest technical strategy, Chemical Engineering Matters. The strategy also includes actions chemical engineers are taking on other global challenges including water, energy and health.

IChemE is a registered charity in England & Wales and a charity registered in Scotland (SC 039661).