Numerous children in developing countries die every year when it is time for them to be weaned. The cause can be traced to the contamination of their new food by bacteria and viruses which cause severe, and often fatal, diarrhoea. British and Malaysian researchers have discovered a simple technique, food fermentation, which makes it possible to check this devastating epidemic.
Every year, almost five million children,
mainly in developing countries, are affected by severe types of
diarrhoea and die as a result. In 70% of cases, this endemic disease
is caused by an absence of food hygiene during the weaning period.
Rice or maize gruel, which is traditionally used as the first solid
food at the end of breastfeeding, are contaminated by various bacteria
(Escherichia coli, Salmonella typhimurium, Campylobacter jejuni,
Shigella, etc.) and can harbour a particular type of virus: the
rotavirus. This health problem is considered a priority by the World
Health Organisation (WHO).
A pragmatic hypothesis
In 1989, some British scientists from the University of Surrey put forward the hypothesis that a lactic-type fermentation of weaning foods, or in other words their biochemical transformation under the effect of enzymes produced by micro-organisms introduced into them, could be a solution to this problem. "Mothers usually prepare a large quantity of rice at a time. They then feed their babies with this gradually, sometimes over the course of several days. To avoid bacterial proliferation in the food, which is extremely swift in hot climates, it should ideally be sterilised by repeated boiling after each use. But the conditions in which these impoverished populations live mean that such a hygiene rule is seldom applied and is in any case quite foreign to local customs. For this reason, we thought of the technique of food fermentation which would check the growth of bacteria and replace the role normally played by boiling," explains Doctor Jane Morgan.
A research partnership was therefore launched in the context of the European programme for Science and Technology for Development (STD2) in collaboration with researchers from the University of Pertanian, Malaysia (State of Selangor, Malaysia).
The goal of their research was to determine what type of fermentation would be capable of countering and preventing the growth of pathogenic bacteria and rotaviruses in typical weaning foods, such as rice gruel, and how such a technique could be applied in average temperature conditions close to 30°, such as those found in tropical environments.
After numerous and often lengthy analyses, the research made it possible to identify a food hygiene practice which was not only reliable, but also easily applicable in the context of the target populations. To counter bacterial proliferation, an aerobic "pre-fermentation" of the food, lasting 24 hours, provides satisfactory hygienic protection. The action required of mothers is very straightforward. All they have to do is to put a pellet which contains the fermenting agents into the gruel and wait until the following day before feeding their children. To combat retroviruses reliably, mothers must also preheat the food before each meal for five minutes at just over 50°, which is much easier than sterilisation by boiling. Tests in the field have been started by the Malaysian team and the clinical part of the study is about to be completed.
What remains to be done is to make this new but simple hygiene practice part of the daily habits of the populations concerned. Its impact will depend on the awareness campaigns which will be carried out on a major scale to make this part of everyday behaviour. "Our results have been hailed by the World Health Organisation, which is strongly encouraging the dissemination of this technique," explains Jane Morgan.