Life preservers: Focus on preservatives

Related tags Antioxidant Nutrition

Life preservers: Focus on preservatives
Natural alternatives to artificially derived preservatives are multiplying, says Chloe Ryan 

Sit through any TV ad break and it swiftly becomes apparent that catering for shoppers who want to slow the effects of ageing is big business. And thanks to a raft of publicity about the health benefits of antioxidant-rich foods such as blueberries and pomegranates, most consumers now associate antioxidants with everything from preventing cancer to looking younger.

However, they have conventionally been used as a completely different form of preservative, preventing the oxidation of processed foods and halting the processes that would lead fats to become rancid.

Now suppliers are being forced to revisit this more traditional function in a fresh way by the shift in demand from synthetic to 'natural' options. Within that, demand for synthetic antioxidants, of which butylated hydroxyanisol (BHA), butylated hydroxtoluene (BHT), tertiary butylhydroquinone (TBHQ) and gallates are the most common, is stagnant, says Frost & Sullivan analyst Kaushik Ramakrishnan Shankar.

Leatherhead Food Research (LFR) says between 2002 and 2006, the value share of BHA in Europe and the US fell from 23.4% to 23.2%, while sales of BHT declined from 3% to 2.9%. By contrast, the value share of antioxidants extracted from herbs increased from 11.9% to 12.4%.

Yet global sales of antioxidants used to reduce oxidative deterioration in processed foods are predicted to total £239.9M in 2010, up from £222.2M in 2007, according to LFR. Shankar values the European antioxidants market at £142.9M in 2008 and claims it has averaged between 3% and 4% growth in the past decade.

"Based on our forecast, the market should be worth about £168.7M in 2010," he says. "If you are looking at the base manufactured food market growing at 3% then you can definitely expect that antioxidants will be growing at that rate." It's naturally derived carotenoids such as lycopene and beta carotene that are partly driving that growth, claims Lisa Ryan, a research scientist at the Functional Food Centre of the UK's Oxford Brookes University.

Carotenoids occur in green plants, fruits and vegetables and also have the advantage of being brightly coloured. "We are seeing an increase in the extraction of natural pigments from fruit and vegetables and using them as antioxidants," says Ryan. "Betanin [a red dye from beets] is increasingly being used in different products as a colourant, and as an antioxidant in things such as sausage, meat paste and fish products."

Vitamins are the largest part of the European antioxidant market. From the vitamin E family, tocopherols, extracted from the oils of nuts and seeds such as sunflower, walnut and soya, are commonly used in yellow fat spreads. L-ascorbate (vitamin C), which occurs naturally in most fruit and vegetables, is also used in fats and oils, margarines and spreads and processed foods.

Charlotte Frederiksen, external communications manager at DSM, a top global antioxidant supplier, says herbal extracts are growing in popularity fast, particularly Rosemary. The plant has been shown to be more effective than BHA and BHT in preserving fat, says LFR.

French company Naturex, which claims to lead the world rosemary extract market with a 20% share of sales, is certainly an ardent fan. One of its most recent launches is XtraBlend RP, a combination of rosemary and pomegranate extracts, sold under its NAT stabil line. Naturex also has developed a range of fruit and vegetable based antioxidants including Swiss Chard 3, a powdered Swiss chard juice, and Acerola Fruit 17, a acerola cherry juice powder.

Danisco, Evesa, Flavex and Vitiva of Slovenia are other European companies active in the herbal extracts market, and in July Vivita launched SyneRox 4, an antioxidant designed to extend the shelf-life of whole milk powder and other concentrated milk products such as ice cream and coffee creamer.

Aside from consumer preference, legal changes lie behind the shift away from synthetically derived antioxidants. "In the past, sulphites (salts or esters of sulphuric acid) were frequently used by food manufacturers on account of their antioxidant properties," says Frederiksen. "Today, manufacturers prefer nature-identical antioxidants such as ascorbates and tocopherols, or combinations thereof. Certain substances, which used to be employed (eg nordihydroguaiaretic acid and Ethoxyquin), have been forbidden, as their safety profile no longer meets requirements."

Some parties are also challenging the use of nitrates and nitrites in organic cured meats. These preservatives are not antioxidants, but anti-microbials and prevent the growth of pathogens. The UK organics body, the Soil Association, is seeking to indefinitely delay an EU regulation that would ban their use from 2011, arguing there are no suitable alternatives.

The UK government Department for Environment, Food and Rural Affairs (DEFRA) is looking into alternatives if a ban occurs. Despite the prevailing mood of consumers, these include sodium ascorbate, BHA, and TBHQ, which it says have all been shown to be effective at preserving cured meats.

A DEFRA document, Alternatives to nitrates and nitrites in organic meat production, published in August 2010, says some herbal extracts can reduce rancidity. "But their effectiveness is dependent on the food matrix, concentration and susceptibility to food processing," it adds, with further work required to establish suitability.

A spokeswoman says DEFRA is working with producers to look at how any changes might affect producers. It will also be looking at the scientific evidence on food safety, before making a decision on whether any changes are necessary.

Elsewhere in Europe other controversial issues demand attention, according to Shankar. "The source for some [antioxidant] vitamins are genetically modified (GM) crops," he says. "Europe is very anti-GM and that is something that has to be addressed by manufacturers."

Another issue the industry is grappling with is the European Food Safety Authority's (EFSA's) refusal to pass any health claims for antioxidant additives so far. Mary Gilsenan, head of regulatory services at LFR, says processors will soon get more guidance on how to substantiate claims. "EFSA is going to engage in a series of meetings where they will give more information on the substantiation of claims," she says. "We hope antioxidants will be part of that programme and when that happens it's likely the criteria for substantiation will be clearer."

But even if EFSA stonewalls health claims, processors insist clinical trials show their antioxidants have clear benefits. "DSM's pure green tea extract Teavigo, for instance, contains a purified form of the most abundant catechin in green tea, called epigallocatechin gallate (EGCG)," says Frederiksen. "The carotenoid lycopene, meanwhile, which occurs in red coloured fruits and vegetables, may have a role in preventing the oxidation of low-density lipoproteins [protein and lipid packages that transport cholesterol through the body]. It may therefore combat atherosclerosis [artery furring] and coronary heart disease. Lycopene is offered by DSM as Redivivo."

That said, Peter Hollman of Wageningen University in the Netherlands welcomes EFSA's cautiousness in approving nutritional claims. "There are many powerful antioxidants that are present in food. The big problem is we are not able to show effects in the body. For instance, polyphenols have very high antioxidant values but the absorption is quite low and the compounds are metabolised during absorption. In the end high antioxidant food has only a very limited effect."

Approval or no approval, the market for antioxidant-rich foods is likely to keep growing, according to LFR, especially in developing countries, where demand for processed foods is increasing.

Against that, Frost & Sullivan's Shankar believes the cost of antioxidants may fall as the number of Asian manufacturing companies competing with giants such as DSM and Danisco rises. That would potentially slow down the rate of value growth from its current 3% to 4% trajectory. "China is entering every ingredient segment. If they [Chinese manufacturers] are able to satisfy quality requirements, they will definitely be able to provide a cost effective solution to what is happening in Europe or the US."

Through all the competition, controversy and regulatory issues awaiting the unwary, one thing is clear. While, as a mature market, antioxidants offer only slight value growth, naturally derived antioxidant-based preservatives show the most promise. fihn

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