Lipid attraction

Fats and oils (lipids) perform many functions in food and food processing and are essential components in many of the foods we need and enjoy. Their functions include: frying and baking, moisture retention, flavour delivery, lubrication and coating, visual appearance, nutrition (they contain oil-soluble vitamins and essential fatty acids), construction of emulsions and foams, aeration of foods, processing aids and satiety.

In addition to their use in frying, cooking and in-home culinary preparations, the inclusion of fat is essential to a wide variety of manufactured foods. Main products in this category include: margarines and spreads; bread, biscuits, cakes, and pastries; confectionery; soups, sauces and dressings; and ice cream.

However, no single fat is capable of performing all of the functions listed in all of the products. Many types of fats from many sources are available, each with its own characteristics. Despite their versatility, fats have only two basic forms: saturated 'bad' fats and unsaturated (including monounsaturated and polyunsaturated). Polyunsaturated fatty acids (PUFAs) are considered the most healthy and some, such as omega-3, can do good.

In general, saturated fats derive from animal sources (rendered from animal tissue, or butterfat from milk) and are solid at room temperature, although some tropical plants (such as coconut and palm) produce oils that are highly saturated.

Saturated fats have come under scrutiny, as excessive intake has been associated with raised cholesterol levels (a contributing factor to heart disease) and some forms of cancer. Vegetable oils are derived from oilseed sources such as corn, soya, rape (canola) and sunflower and in their pure forms contain high proportions of unsaturated fats. Other vegetable sources are fruits (olives, avocados) and tubers (groundnuts).Marine sources include oily fish, fish livers and algae.

The most commonly used saturated fats include butter, lard, suet and certain hydrogenated vegetable oils used in margarine and vegetable shortening.

An additional health risk that has been highlighted more recently concerns partially hydrogenated, or hardened, fats and the resultant levels of undesirable trans fats (trans fatty acids). In order to increase the plasticity of liquid vegetable oils (to make them spreadable) and to reduce rancidity, it has been common practice since the early 1900s to harden them by adding hydrogen (hydrogenation). As with saturated fats, trans fats are linked with the same health risks.

However, trans fats, from hydrogenated or partially hydrogenated oils, are generally considered to be a greater health risk than the small amounts of saturated fats that occur naturally.

In many countries, trans fats are now regulated and must be disclosed on product labels and, due to pressure from governments and health lobbies, many manufacturers are voluntarily either removing trans fats from their products, or developing trans-free ones.

Fats and health

Fats in the diet present an apparent paradox. On the one hand, they are essential to a well-balanced diet and on the other consumers are reminded, by government agencies and pressure groups, how harmful fats can be. As always, the truth probably lies somewhere in the middle.

Although fats form an essential part of a healthy diet, it is certainly the case, borne out by figures from the Food and Agricultural Organisation (FAO) of the United Nations that the average, per person, intake of fats has been increasing in the developed and developing world.

And only recently has the importance in the diet of omega-3 and omega-6 fats become widely appreciated.

However, the average western diet is not deficient in omega-6 (which is mainly derived from plant oils) but is severely deficient in omega-3. Some estimates put the dietary deficiency of omega-3 type fats at 25% of the recommended level. While it can be found in plant oils, such as flax/linseed and borrage, omega-3's most effective form is found in fish oils. Oil from fish contains eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA); both of which are considered the most effective omega-3 fatty acids.

Most fish oil supplements are 18% EPA and 12% DHA, or a total of 30% omega-3. Docosapentaenoic acid (DPA) is another beneficial long chain fatty acid. These omega-3 fatty acids help to control blood triglycerides and may inhibit the progression of atherosclerosis. The omega-3 fatty acids in fish oil also help to balance the omega-6 fatty acids. When these two groups of fatty acids are out of balance, the body releases chemicals that promote inflammation.

Although fish oils are regarded as the most nutritionally beneficial PUFAs, researchers believe that ALA (alpha-linolenic acid found in flax/linseed oil and other vegetable oils) is beneficial for protecting against heart and vessel disease and for lowering cholesterol and triglyceride levels.

The main sources of PUFAs are: fish oil, pure cod liver oil, pure fish oil, salmon oil, sunflower oil, safflower, high-EPA fish oil, evening primrose oil, starflower (borage) oil, flaxseed oil, linoleic acid and algae.

So far, omega-3 PUFAs have successfully established uses in dietary supplements for cholesterol reduction, cardiovascular and various medical indications; food additives in margarine, milk, yoghurt and eggs; infant food for pre-term and first-age formulae; and pet foods and animal feeds.

Poor stability blights the use of omega-3 in foods (especially that which is derived from fish oils), along with its tendency to oxidise. Many dried and encapsulated products can overcome this problem, however.

The market for omega-3 oils

Most omega-3 usage is in supplements but an increasing number of food, drink and infant food products now contain omega-3 fatty acids. Measuring this market is difficult as levels of omega-3 fatty acids vary between sources. Some companies now supply them in concentrated or encapsulated form.

RTS research into this area indicates that the market is growing rapidly - more than 10% per year. It has been calculated that in 2006, the use of all added omega-3 fatty acids in Europe reached a value of €250M. Of this, approximately €100M was from marine sources.

The global market for fats and oils

In total, the FAO puts the global production of all vegetable oils at 118Mt. Of course, not all of this is used by the food industry. However, the food industry does use a considerable 'hidden' quantity for essential functions, such as lubrication, processing aids (release agents) and for frying. Consumers also purchase oils and fats for cooking and culinary use.

An analysis of the top 50 global markets shows that total industrial usage of added oils and fats has now reached 14.4Mt. Overall, this figure is growing by 1.4% year-on-year but growth varies significantly between regions. Consumer purchases in these markets are put at an additional 30Mt.

Growth is slowest in Europe. Not only is this due to slow growth of the base markets, but consumer and other pressures have been forcing manufacturers to either substitute, or use less added fat in their recipes.

This contrasts sharply with the Asia Pacific region, where the growth in industrially manufactured foods is boosting usage of fat as an ingredient by 2.8%, year-on-year. Eastern Europe is showing the fastest growth rate, spurred by an increase in production of added value and convenience foods.

For more information, contact Jamie Rice, RTS Resource, at +44 (0) 1902 422282 jamie.rice@rts-resource.com