The mushroom solution

OVER the years, the food industry, along with governments and organisations, has increased efforts at promoting health and wellness through better products and procedures. Triggered by the growing rate of non-communicable diseases (NCD) worldwide, reducing fat, sugar, and sodium in foods, has become the norm in the industry. Likewise, effective food labelling and regulating of fast-food advertising, amongst others, further the health campaign. But for all the work, is there a change in obesity levels? The obesity rate is still growing. According to World Health Organisation statistics, there were 1.4 billion overweight and obese individuals in 2008. The number has risen to 1.6 billion. One reason is that consumers have not really changed their eating habits.

A solution is to re-engineer food to taste and look the same, but contain less fat, said researchers at the Institution of Chemical Engineers (IChemE). Needless to say, for years now, the goal of food companies has been the same: to reduce calories with ingredients that mimic food fats, but the taste and texture have to be authentic.

The candidate ingredient for this seems to be hydrophobins, a natural protein extracted from fungi like mushrooms. In food, this protein can act as a ‘foam’ and an ‘emulsifier’ that aerates and helps bind ingredients together – a function that is usually achieved with fats and sugars. The process determines the mouth feel and flavour of the food and produces distinctive food characteristics enjoyed by consumers, such as the frothy head on beer and the crumb structure in bread.

Citing work by chemical engineers at the University of Birmingham1 in the UK, IChemE researchers said that hydrophobins have the potential to halve fat levels in some foods by replacing them with highly stable air-filled emulsions. Despite removing the fat, the foods retained the same eating experience as full fat versions without changing texture or flavour.

The drawback
The discovery means that high-calorie foods heavily reliant on foams and emulsifiers – such as chocolate, ice cream, mayonnaise, salad dressings, whipped cream, mousses, milk shakes, smoothies, crisps, marshmallows, cakes, ale, lagers, bread and even hot drinks like cappuccinos – can now be re-engineered in a way that avoids the compromises associated with many diet foods.

However, there are challenges. In their latest review2 of food foams and emulsifiers, the University of Birmingham and the University of Wolverhampton indicated that developments like hydrophobins have not been widely used ‘due to the conservative nature of the food industry’.

David Brown, chief executive at IChemE, said: “Obesity is a major issue even to the extent that some governments have legislated and introduced ‘fat taxes’ on fast foods. In countries like the UK, the NHS estimates it spends over ￡5bn each year on treating obesity related diseases such as heart attacks.

“Re-engineering our food is another serious option in the battle against obesity. But it will take time. The key will be public confidence and acceptance. Many consumers are unwilling to compromise their eating and drinking experience associated with some diet products.

“Hydrophobins may be able to overcome this fundamental resistance and follow successful attempts to reduce sugar levels in foods over recent years. Artificial sweeteners and natural sugar substitutes are now widely used and accepted in foods by consumers, and, in particular, has helped to reduce sugar consumption especially in fizzy drinks.

“If the same level of trust can be achieved with hydrophobins, then food manufacturers could be persuaded to re-formulate brands worth billions of dollars and make the single biggest contribution to promoting healthier lifestyles.”

The role of chemical engineers in the food sector is explored in IChemE’s latest technical strategy, ChemMujer