Johannesburg, 10 November 2010 (IRIN) - Most Zambian children regularly tuck in to `nshima', a stiff maize porridge, but if they can be persuaded to eat an orange-coloured variety made of biofortified maize, their health prospects could be greatly enhanced.

More than half of Zambia's under-five children are affected by vitamin A deficiency, which can increase the risk of illness, retard growth and cause blindness, according to the government's National Food and Nutrition Commission.

The government tried fortifying margarine with vitamin A in the 1970s and sugar since the 1990s, but neither of these efforts proved to be very successful. A study by the Commission in 2003 found vitamin A deficiency levels to be as high as 54 percent in children under five, and 13 percent in women aged 15-49.

"People in the rural areas do not eat margarine," explained Eliab Simpungwe, a scientist involved in efforts to grow biofortified crops and orange maize in Zambia. Simpungwe works with HarvestPlus, a global alliance of research institutions and implementing agencies working together to breed and disseminate crops for better nutrition.

"Vitamin A degenerates very quickly in sugar. Transportation of sugar to rural areas takes a long time and by the time it gets to the people, there is very little trace of the vitamin in it," he said.

In the past few years, developing countries have launched several programmes to fortify staples with vitamin A and iron. Biofortification is the process of breeding higher levels of essential micronutrients such as vitamin A, iron, and zinc in food crops.

Beta-carotene

Zambia has also made its own efforts to biofortify maize with vitamin A - led by the government's Zambia Agricultural Research Institute (ZARI), which is collaborating with HarvestPlus.

After three years of work - identifying maize varieties with high beta-carotene content and then cross-breeding them to increase the content naturally - the scientists appear to have been successful.

Beta-carotene which is converted in the body as vitamin A is naturally found in maize, explained Simpungwe. The researchers led by ZARI have managed to develop a maize variety with a beta-carotene content of nine milligrams per gram, which should improve levels of vitamin A in consumers quite substantially, he said.

"We are aiming to get to a maize variety which will provide 10-15 milligrams of beta-carotene per gram, which is the optimum level," said Simpungwe. The researchers arrived at the figure after taking into account the amount of maize an average Zambian consumed in a year, which is 160kg.

"We are going to roll out seed for evaluation to at least 10,000 farmers in three maize-producing provinces - Eastern, Central and Southern - in 2011," said Simpungwe.

Based on the evaluation findings, the varieties will be released to reach at least 25,000 farmers in 2012.

The team got a boost earlier this year with the publication of the results of a study by Iowa State University in the USA which found that maize bred to contain increased levels of beta-carotene is a good source of vitamin A.

The researchers found that beta-carotene in maize was converted to vitamin A at a higher rate than beta-carotene in vegetables, including spinach and carrots.

The breakthrough comes as the first global conference on biofortification began in the USA on 9 November.

Taste and acceptance

In a country where white maize is still preferred to yellow maize, would the bright orange variety find acceptance?

Zambians have been lukewarm about yellow maize because of its taste and the perception it is "drought food", as it was frequently distributed as food aid, according to a HarvestPlus study.

Another study - assessed and approved by the research ethics committees of the University of Zambia and the University of Greenwich, and which also involved the National Institute of Scientific and Industrial Research - found that orange maize was "likely" to be accepted by consumers in Zambia.

Simpungwe said he had run his own trials at home and found the maize to be a hit with his children and friends. "Unlike white maize which has a flat taste, the orange maize has a sweetish taste which the children loved."

But there remain challenges around wide acceptance, noted a report prepared for the International Center for Research on Women and the Bill and Melinda Gates Foundation, which has helped fund efforts to biofortify maize in Zambia.

Women play a key role in deciding what is consumed in households, said Miriam Chaiken, a researcher at New Mexico State University, and author of the report.

Variables such as flavour, ease of cooking and perceived digestibility for children matter to them, and these need to be tested further in a Zambian rural context to create effective marketing strategies. People also need to understand the linkages between illness and vitamin A deficiency.

She suggested targeting women's groups and small-scale farmers with information, possibly through community radio, and by distributing orange maize seeds.

Simpungwe said the seeds will be made freely available initially, and subsidized thereafter.