Functional food is any processed food claimed to have a health-promoting or disease-preventing property that goes beyond the basic macronutrient and micronutrient functions.

Common examples are:

  • omega-3 fish oil-enriched breads
  • plant sterol and stannol-enriched margarines
  • yoghurt enriched with probiotic bacteria
  • calcium-enriched milk
  • caffeine-enriched beverages like coffee.

The development of functional foods is in response to customer demand. Consumers want ‘healthier’ foods, and the challenge the food industry faces is to enhance the bioactiveantioxidant or mood-enhancing potential of a food without reducing its appeal or making it too expensive.

Consumer surveys of supermarket shoppers have indicated that ‘mood foods’, particularly those that have the ability to reduce stress and relieve anxiety, would be popular if available.

An example – fish oil encapsulation

A body of research has shown that regularly consuming omega-3 fatty acids in the form of fish oil can play a significant role in preventing cardiovascular disease. Fish oil is well known for its off-putting smell and taste, so a team of researchers led by Professor Harjinder Singh, at the Riddet Institute attached to Massey University in Palmerston North, set themselves the challenge of making it more readily available in the diet.

The result is a technology that encapsulates omega-3 molecules with a nanoscale-level coating to give protection from light, oxygentemperature and acidity. With this coating, omega-3 can be added to food products like bread, ice cream, yoghurt, muesli and juice. A single serving can then be designed to give a complete daily requirement without smelling or tasting like fish.

Read this article, Fish oil in functional food for information on encapsulated fish oil and functional foods.

Eicosopentaenoic acid (EPA) is one of the omega-3 fatty acids found in fish oil. It is an unsaturated fatty acid with 5 C=C double bonds present in each molecule.

Fruit – the future of functional foods

Research being conducted at the New Zealand Institute for Plant & Food Research Limited is investigating plant-based functional foods for the national and international markets.

Dr Arjan Scheepens is leading a team of researchers developing functional foods that have a beneficial effect on mood and cognitive function (a person’s ability to process thoughts). Work is being done with polyphenolic compounds present in berry fruits, which have the potential to be used in anti-anxiety foods that can improve mental wellbeing.

His team have also discovered a fruit extract that can improve the mental processes needed to carry out tasks (cognitive ability).

Bioactivity and bioavailability

One of the difficulties faced by researchers in this field is that, although a phytochemical may have bioactivity, it might not have a suitable level of bioavailability

Bioactivity means the chemical can exert some effect on living cells. For example, caffeine present in coffee can bind with receptors in the brain resulting in increased activity within the brain. The net effect is increased alertness, a feeling of being energised and an elevation of mood.

Bioavailability means how readily the chemical can enter the brain to exert its effect. Not only is caffeine bioactive, it also has a high bioavailability.

Caffeine has a similar structure to adenosine, which is a brain chemical that has a calming action. Caffeine can displace adenosine and exert an increased activity effect.

Useful link

Functional foods are foods with added nutritional benefit. But do we need them? Dr Roger Lentle, Associate Professor in Clinical Nutrition at Massey University, discusses the issues in this audio from Te Papa.

    Published 18 March 2011, Updated 20 November 2014