While fortification of food products with folic acid to reduce the incidence of birth defects is well-established in cereal and bakery, taking folic acid into dairy has remained largely ignored.
But researchers from Louisiana State University Agricultural Center in Baton Rouge report that folic acid-fortified yoghurt can be prepared, but levels of the nutrient do affect flavour - and making healthy products taste good is an ongoing challenge for the food industry.
"Development of dairy products with new flavours and health benefits helps the dairy industry increase sales of products as well as provide consumers with products they enjoy," wrote the authors.
"Lemon flavoured, folic acid fortified yogurts had high flavour and body and texture scores which is of use to the dairy industry," they added.
Folate is found in foods such as green leafy vegetables, chick peas and lentils, and an overwhelming body of evidence links has linked folate deficiency in early pregnancy to increased risk of neural tube defects (NTD) - most commonly spina bifida and anencephaly - in infants.
This connection led to the 1998 introduction of public health measures in the US and Canada, where all grain products are fortified with folic acid - the synthetic, bioavailable form of folate.
While preliminary evidence indicates that the measure is having an effect with a reported 15 to 50 per cent reduction in NTD incidence, parallel measures in European countries, including the UK and Ireland, are still on the table.
But with increasing levels of wheat and gluten intolerance, as well as individual preferences, finding alternative vehicles for folic acid fortification may open the way for fortified dairy, assuming the taste of the end product is acceptable to consumers.
Lemon and folic acid The Louisiana-based researchers formulated lemon-flavoured yoghurts containing 0, 25, 50, 75, and 100 of the recommended daily amount of folic acid (400 micrograms).
Addition of the micronutrient was tested before and after the pasteurisation stage of yogurt production.
Adding folic acid after pasteurisation produced end products with the highest content of the nutrient, and this also produced yoghurts with lower viscosity, which adversely affected consumer preference with more viscous yoghurts preferred.
When tested by consumers, the researchers note that higher folic acid levels led to lower flavour ratings, but the simple addition of the lemon flavouring did increase consumer preference, compared to plain yoghurts.
While more research is clearly needed the study does point to a possible avenue of future development as the market for functional dairy products changes over time.
Functional dairy The functional dairy drink market is booming, with Zenith International reporting it to be worth €3,400m. Analysts said drinks consumption across West Europe, United States and Japan rose by 12 per cent from a 2005 point of 892 million litres.
And by the end of this year consumption could hit the 1,111 million litre mark, the report added.
This market is dominated by probiotic dairy drinks, but this area is slowly changing.
Zenith analyst Jenny Foulds said last year: "As health conscious consumers seek more individual solutions and choices, the uppermost challenge for those entering the functional dairy drinks category is how to respond to this ever changing agenda.
Product positioning will become increasingly important, as will appealing to principles such as convenience, provenance and health" Source: LWT - Food Science and Technology Volume 41, Issue 7, Pages 1335-1343 "Effect of folic acid fortification on the characteristics of lemon yogurt" Authors: C.A. Boeneke, K.J. Aryana